1 // Copyright 2015 The Go Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style
3 // license that can be found in the LICENSE file.
4
5 // Simplifications that apply to all backend architectures. As an example, this
6 // Go source code
7 //
8 // y := 0 * x
9 //
10 // can be translated into y := 0 without losing any information, which saves a
11 // pointless multiplication instruction. Other .rules files in this directory
12 // (for example AMD64.rules) contain rules specific to the architecture in the
13 // filename. The rules here apply to every architecture.
14 //
15 // The code for parsing this file lives in rulegen.go; this file generates
16 // ssa/rewritegeneric.go.
17
18 // values are specified using the following format:
19 // (op <type> [auxint] {aux} arg0 arg1 ...)
20 // the type, aux, and auxint fields are optional
21 // on the matching side
22 // - the type, aux, and auxint fields must match if they are specified.
23 // - the first occurrence of a variable defines that variable. Subsequent
24 // uses must match (be == to) the first use.
25 // - v is defined to be the value matched.
26 // - an additional conditional can be provided after the match pattern with "&&".
27 // on the generated side
28 // - the type of the top-level expression is the same as the one on the left-hand side.
29 // - the type of any subexpressions must be specified explicitly (or
30 // be specified in the op's type field).
31 // - auxint will be 0 if not specified.
32 // - aux will be nil if not specified.
33
34 // blocks are specified using the following format:
35 // (kind controlvalue succ0 succ1 ...)
36 // controlvalue must be "nil" or a value expression
37 // succ* fields must be variables
38 // For now, the generated successors must be a permutation of the matched successors.
39
40 // constant folding
41 (Trunc16to8 (Const16 [c])) => (Const8 [int8(c)])
42 (Trunc32to8 (Const32 [c])) => (Const8 [int8(c)])
43 (Trunc32to16 (Const32 [c])) => (Const16 [int16(c)])
44 (Trunc64to8 (Const64 [c])) => (Const8 [int8(c)])
45 (Trunc64to16 (Const64 [c])) => (Const16 [int16(c)])
46 (Trunc64to32 (Const64 [c])) => (Const32 [int32(c)])
47 (Cvt64Fto32F (Const64F [c])) => (Const32F [float32(c)])
48 (Cvt32Fto64F (Const32F [c])) => (Const64F [float64(c)])
49 (Cvt32to32F (Const32 [c])) => (Const32F [float32(c)])
50 (Cvt32to64F (Const32 [c])) => (Const64F [float64(c)])
51 (Cvt64to32F (Const64 [c])) => (Const32F [float32(c)])
52 (Cvt64to64F (Const64 [c])) => (Const64F [float64(c)])
53 (Cvt32Fto32 (Const32F [c])) => (Const32 [int32(c)])
54 (Cvt32Fto64 (Const32F [c])) => (Const64 [int64(c)])
55 (Cvt64Fto32 (Const64F [c])) => (Const32 [int32(c)])
56 (Cvt64Fto64 (Const64F [c])) => (Const64 [int64(c)])
57 (Round32F x:(Const32F)) => x
58 (Round64F x:(Const64F)) => x
59 (CvtBoolToUint8 (ConstBool [false])) => (Const8 [0])
60 (CvtBoolToUint8 (ConstBool [true])) => (Const8 [1])
61 (BitLen64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len64(uint64(c)))])
62 (BitLen32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len32(uint32(c)))])
63 (BitLen16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len16(uint16(c)))])
64 (BitLen8 (Const8 [c])) && config.PtrSize == 8 => (Const64 [int64(bits.Len8(uint8(c)))])
65 (BitLen64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len64(uint64(c)))])
66 (BitLen32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len32(uint32(c)))])
67 (BitLen16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len16(uint16(c)))])
68 (BitLen8 (Const8 [c])) && config.PtrSize == 4 => (Const32 [int32(bits.Len8(uint8(c)))])
69
70 (Trunc16to8 (ZeroExt8to16 x)) => x
71 (Trunc32to8 (ZeroExt8to32 x)) => x
72 (Trunc32to16 (ZeroExt8to32 x)) => (ZeroExt8to16 x)
73 (Trunc32to16 (ZeroExt16to32 x)) => x
74 (Trunc64to8 (ZeroExt8to64 x)) => x
75 (Trunc64to16 (ZeroExt8to64 x)) => (ZeroExt8to16 x)
76 (Trunc64to16 (ZeroExt16to64 x)) => x
77 (Trunc64to32 (ZeroExt8to64 x)) => (ZeroExt8to32 x)
78 (Trunc64to32 (ZeroExt16to64 x)) => (ZeroExt16to32 x)
79 (Trunc64to32 (ZeroExt32to64 x)) => x
80 (Trunc16to8 (SignExt8to16 x)) => x
81 (Trunc32to8 (SignExt8to32 x)) => x
82 (Trunc32to16 (SignExt8to32 x)) => (SignExt8to16 x)
83 (Trunc32to16 (SignExt16to32 x)) => x
84 (Trunc64to8 (SignExt8to64 x)) => x
85 (Trunc64to16 (SignExt8to64 x)) => (SignExt8to16 x)
86 (Trunc64to16 (SignExt16to64 x)) => x
87 (Trunc64to32 (SignExt8to64 x)) => (SignExt8to32 x)
88 (Trunc64to32 (SignExt16to64 x)) => (SignExt16to32 x)
89 (Trunc64to32 (SignExt32to64 x)) => x
90
91 (ZeroExt8to16 (Const8 [c])) => (Const16 [int16( uint8(c))])
92 (ZeroExt8to32 (Const8 [c])) => (Const32 [int32( uint8(c))])
93 (ZeroExt8to64 (Const8 [c])) => (Const64 [int64( uint8(c))])
94 (ZeroExt16to32 (Const16 [c])) => (Const32 [int32(uint16(c))])
95 (ZeroExt16to64 (Const16 [c])) => (Const64 [int64(uint16(c))])
96 (ZeroExt32to64 (Const32 [c])) => (Const64 [int64(uint32(c))])
97 (SignExt8to16 (Const8 [c])) => (Const16 [int16(c)])
98 (SignExt8to32 (Const8 [c])) => (Const32 [int32(c)])
99 (SignExt8to64 (Const8 [c])) => (Const64 [int64(c)])
100 (SignExt16to32 (Const16 [c])) => (Const32 [int32(c)])
101 (SignExt16to64 (Const16 [c])) => (Const64 [int64(c)])
102 (SignExt32to64 (Const32 [c])) => (Const64 [int64(c)])
103
104 (Neg8 (Const8 [c])) => (Const8 [-c])
105 (Neg16 (Const16 [c])) => (Const16 [-c])
106 (Neg32 (Const32 [c])) => (Const32 [-c])
107 (Neg64 (Const64 [c])) => (Const64 [-c])
108 (Neg32F (Const32F [c])) && c != 0 => (Const32F [-c])
109 (Neg64F (Const64F [c])) && c != 0 => (Const64F [-c])
110
111 (Add8 (Const8 [c]) (Const8 [d])) => (Const8 [c+d])
112 (Add16 (Const16 [c]) (Const16 [d])) => (Const16 [c+d])
113 (Add32 (Const32 [c]) (Const32 [d])) => (Const32 [c+d])
114 (Add64 (Const64 [c]) (Const64 [d])) => (Const64 [c+d])
115 (Add32F (Const32F [c]) (Const32F [d])) && c+d == c+d => (Const32F [c+d])
116 (Add64F (Const64F [c]) (Const64F [d])) && c+d == c+d => (Const64F [c+d])
117 (AddPtr <t> x (Const64 [c])) => (OffPtr <t> x [c])
118 (AddPtr <t> x (Const32 [c])) => (OffPtr <t> x [int64(c)])
119
120 (Sub8 (Const8 [c]) (Const8 [d])) => (Const8 [c-d])
121 (Sub16 (Const16 [c]) (Const16 [d])) => (Const16 [c-d])
122 (Sub32 (Const32 [c]) (Const32 [d])) => (Const32 [c-d])
123 (Sub64 (Const64 [c]) (Const64 [d])) => (Const64 [c-d])
124 (Sub32F (Const32F [c]) (Const32F [d])) && c-d == c-d => (Const32F [c-d])
125 (Sub64F (Const64F [c]) (Const64F [d])) && c-d == c-d => (Const64F [c-d])
126
127 (Mul8 (Const8 [c]) (Const8 [d])) => (Const8 [c*d])
128 (Mul16 (Const16 [c]) (Const16 [d])) => (Const16 [c*d])
129 (Mul32 (Const32 [c]) (Const32 [d])) => (Const32 [c*d])
130 (Mul64 (Const64 [c]) (Const64 [d])) => (Const64 [c*d])
131 (Mul32F (Const32F [c]) (Const32F [d])) && c*d == c*d => (Const32F [c*d])
132 (Mul64F (Const64F [c]) (Const64F [d])) && c*d == c*d => (Const64F [c*d])
133
134 (And8 (Const8 [c]) (Const8 [d])) => (Const8 [c&d])
135 (And16 (Const16 [c]) (Const16 [d])) => (Const16 [c&d])
136 (And32 (Const32 [c]) (Const32 [d])) => (Const32 [c&d])
137 (And64 (Const64 [c]) (Const64 [d])) => (Const64 [c&d])
138
139 (Or8 (Const8 [c]) (Const8 [d])) => (Const8 [c|d])
140 (Or16 (Const16 [c]) (Const16 [d])) => (Const16 [c|d])
141 (Or32 (Const32 [c]) (Const32 [d])) => (Const32 [c|d])
142 (Or64 (Const64 [c]) (Const64 [d])) => (Const64 [c|d])
143
144 (Xor8 (Const8 [c]) (Const8 [d])) => (Const8 [c^d])
145 (Xor16 (Const16 [c]) (Const16 [d])) => (Const16 [c^d])
146 (Xor32 (Const32 [c]) (Const32 [d])) => (Const32 [c^d])
147 (Xor64 (Const64 [c]) (Const64 [d])) => (Const64 [c^d])
148
149 (Ctz64 (Const64 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz64(c))])
150 (Ctz32 (Const32 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz32(c))])
151 (Ctz16 (Const16 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz16(c))])
152 (Ctz8 (Const8 [c])) && config.PtrSize == 4 => (Const32 [int32(ntz8(c))])
153
154 (Ctz64 (Const64 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz64(c))])
155 (Ctz32 (Const32 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz32(c))])
156 (Ctz16 (Const16 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz16(c))])
157 (Ctz8 (Const8 [c])) && config.PtrSize == 8 => (Const64 [int64(ntz8(c))])
158
159 (Div8 (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [c/d])
160 (Div16 (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [c/d])
161 (Div32 (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [c/d])
162 (Div64 (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [c/d])
163 (Div8u (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [int8(uint8(c)/uint8(d))])
164 (Div16u (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [int16(uint16(c)/uint16(d))])
165 (Div32u (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [int32(uint32(c)/uint32(d))])
166 (Div64u (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [int64(uint64(c)/uint64(d))])
167 (Div32F (Const32F [c]) (Const32F [d])) && c/d == c/d => (Const32F [c/d])
168 (Div64F (Const64F [c]) (Const64F [d])) && c/d == c/d => (Const64F [c/d])
169 (Select0 (Div128u (Const64 [0]) lo y)) => (Div64u lo y)
170 (Select1 (Div128u (Const64 [0]) lo y)) => (Mod64u lo y)
171
172 (Not (ConstBool [c])) => (ConstBool [!c])
173
174 (Floor (Const64F [c])) => (Const64F [math.Floor(c)])
175 (Ceil (Const64F [c])) => (Const64F [math.Ceil(c)])
176 (Trunc (Const64F [c])) => (Const64F [math.Trunc(c)])
177 (RoundToEven (Const64F [c])) => (Const64F [math.RoundToEven(c)])
178
179 // Convert x * 1 to x.
180 (Mul(8|16|32|64) (Const(8|16|32|64) [1]) x) => x
181 (Select0 (Mul(32|64)uover (Const(32|64) [1]) x)) => x
182 (Select1 (Mul(32|64)uover (Const(32|64) [1]) x)) => (ConstBool [false])
183
184 // Convert x * -1 to -x.
185 (Mul(8|16|32|64) (Const(8|16|32|64) [-1]) x) => (Neg(8|16|32|64) x)
186
187 // DeMorgan's Laws
188 (And(8|16|32|64) <t> (Com(8|16|32|64) x) (Com(8|16|32|64) y)) => (Com(8|16|32|64) (Or(8|16|32|64) <t> x y))
189 (Or(8|16|32|64) <t> (Com(8|16|32|64) x) (Com(8|16|32|64) y)) => (Com(8|16|32|64) (And(8|16|32|64) <t> x y))
190
191 // Convert multiplication by a power of two to a shift.
192 (Mul8 <t> n (Const8 [c])) && isPowerOfTwo(c) => (Lsh8x64 <t> n (Const64 <typ.UInt64> [log8(c)]))
193 (Mul16 <t> n (Const16 [c])) && isPowerOfTwo(c) => (Lsh16x64 <t> n (Const64 <typ.UInt64> [log16(c)]))
194 (Mul32 <t> n (Const32 [c])) && isPowerOfTwo(c) => (Lsh32x64 <t> n (Const64 <typ.UInt64> [log32(c)]))
195 (Mul64 <t> n (Const64 [c])) && isPowerOfTwo(c) => (Lsh64x64 <t> n (Const64 <typ.UInt64> [log64(c)]))
196 (Mul8 <t> n (Const8 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg8 (Lsh8x64 <t> n (Const64 <typ.UInt64> [log8(-c)])))
197 (Mul16 <t> n (Const16 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg16 (Lsh16x64 <t> n (Const64 <typ.UInt64> [log16(-c)])))
198 (Mul32 <t> n (Const32 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg32 (Lsh32x64 <t> n (Const64 <typ.UInt64> [log32(-c)])))
199 (Mul64 <t> n (Const64 [c])) && t.IsSigned() && isPowerOfTwo(-c) => (Neg64 (Lsh64x64 <t> n (Const64 <typ.UInt64> [log64(-c)])))
200
201 (Mod8 (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [c % d])
202 (Mod16 (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [c % d])
203 (Mod32 (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [c % d])
204 (Mod64 (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [c % d])
205
206 (Mod8u (Const8 [c]) (Const8 [d])) && d != 0 => (Const8 [int8(uint8(c) % uint8(d))])
207 (Mod16u (Const16 [c]) (Const16 [d])) && d != 0 => (Const16 [int16(uint16(c) % uint16(d))])
208 (Mod32u (Const32 [c]) (Const32 [d])) && d != 0 => (Const32 [int32(uint32(c) % uint32(d))])
209 (Mod64u (Const64 [c]) (Const64 [d])) && d != 0 => (Const64 [int64(uint64(c) % uint64(d))])
210
211 (Lsh64x64 (Const64 [c]) (Const64 [d])) => (Const64 [c << uint64(d)])
212 (Rsh64x64 (Const64 [c]) (Const64 [d])) => (Const64 [c >> uint64(d)])
213 (Rsh64Ux64 (Const64 [c]) (Const64 [d])) => (Const64 [int64(uint64(c) >> uint64(d))])
214 (Lsh32x64 (Const32 [c]) (Const64 [d])) => (Const32 [c << uint64(d)])
215 (Rsh32x64 (Const32 [c]) (Const64 [d])) => (Const32 [c >> uint64(d)])
216 (Rsh32Ux64 (Const32 [c]) (Const64 [d])) => (Const32 [int32(uint32(c) >> uint64(d))])
217 (Lsh16x64 (Const16 [c]) (Const64 [d])) => (Const16 [c << uint64(d)])
218 (Rsh16x64 (Const16 [c]) (Const64 [d])) => (Const16 [c >> uint64(d)])
219 (Rsh16Ux64 (Const16 [c]) (Const64 [d])) => (Const16 [int16(uint16(c) >> uint64(d))])
220 (Lsh8x64 (Const8 [c]) (Const64 [d])) => (Const8 [c << uint64(d)])
221 (Rsh8x64 (Const8 [c]) (Const64 [d])) => (Const8 [c >> uint64(d)])
222 (Rsh8Ux64 (Const8 [c]) (Const64 [d])) => (Const8 [int8(uint8(c) >> uint64(d))])
223
224 // Fold IsInBounds when the range of the index cannot exceed the limit.
225 (IsInBounds (ZeroExt8to32 _) (Const32 [c])) && (1 << 8) <= c => (ConstBool [true])
226 (IsInBounds (ZeroExt8to64 _) (Const64 [c])) && (1 << 8) <= c => (ConstBool [true])
227 (IsInBounds (ZeroExt16to32 _) (Const32 [c])) && (1 << 16) <= c => (ConstBool [true])
228 (IsInBounds (ZeroExt16to64 _) (Const64 [c])) && (1 << 16) <= c => (ConstBool [true])
229 (IsInBounds x x) => (ConstBool [false])
230 (IsInBounds (And8 (Const8 [c]) _) (Const8 [d])) && 0 <= c && c < d => (ConstBool [true])
231 (IsInBounds (ZeroExt8to16 (And8 (Const8 [c]) _)) (Const16 [d])) && 0 <= c && int16(c) < d => (ConstBool [true])
232 (IsInBounds (ZeroExt8to32 (And8 (Const8 [c]) _)) (Const32 [d])) && 0 <= c && int32(c) < d => (ConstBool [true])
233 (IsInBounds (ZeroExt8to64 (And8 (Const8 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
234 (IsInBounds (And16 (Const16 [c]) _) (Const16 [d])) && 0 <= c && c < d => (ConstBool [true])
235 (IsInBounds (ZeroExt16to32 (And16 (Const16 [c]) _)) (Const32 [d])) && 0 <= c && int32(c) < d => (ConstBool [true])
236 (IsInBounds (ZeroExt16to64 (And16 (Const16 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
237 (IsInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c < d => (ConstBool [true])
238 (IsInBounds (ZeroExt32to64 (And32 (Const32 [c]) _)) (Const64 [d])) && 0 <= c && int64(c) < d => (ConstBool [true])
239 (IsInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c < d => (ConstBool [true])
240 (IsInBounds (Const32 [c]) (Const32 [d])) => (ConstBool [0 <= c && c < d])
241 (IsInBounds (Const64 [c]) (Const64 [d])) => (ConstBool [0 <= c && c < d])
242 // (Mod64u x y) is always between 0 (inclusive) and y (exclusive).
243 (IsInBounds (Mod32u _ y) y) => (ConstBool [true])
244 (IsInBounds (Mod64u _ y) y) => (ConstBool [true])
245 // Right shifting an unsigned number limits its value.
246 (IsInBounds (ZeroExt8to64 (Rsh8Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
247 (IsInBounds (ZeroExt8to32 (Rsh8Ux64 _ (Const64 [c]))) (Const32 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
248 (IsInBounds (ZeroExt8to16 (Rsh8Ux64 _ (Const64 [c]))) (Const16 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
249 (IsInBounds (Rsh8Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 8 && 1<<uint( 8-c)-1 < d => (ConstBool [true])
250 (IsInBounds (ZeroExt16to64 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
251 (IsInBounds (ZeroExt16to32 (Rsh16Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
252 (IsInBounds (Rsh16Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 16 && 1<<uint(16-c)-1 < d => (ConstBool [true])
253 (IsInBounds (ZeroExt32to64 (Rsh32Ux64 _ (Const64 [c]))) (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d => (ConstBool [true])
254 (IsInBounds (Rsh32Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 32 && 1<<uint(32-c)-1 < d => (ConstBool [true])
255 (IsInBounds (Rsh64Ux64 _ (Const64 [c])) (Const64 [d])) && 0 < c && c < 64 && 1<<uint(64-c)-1 < d => (ConstBool [true])
256
257 (IsSliceInBounds x x) => (ConstBool [true])
258 (IsSliceInBounds (And32 (Const32 [c]) _) (Const32 [d])) && 0 <= c && c <= d => (ConstBool [true])
259 (IsSliceInBounds (And64 (Const64 [c]) _) (Const64 [d])) && 0 <= c && c <= d => (ConstBool [true])
260 (IsSliceInBounds (Const32 [0]) _) => (ConstBool [true])
261 (IsSliceInBounds (Const64 [0]) _) => (ConstBool [true])
262 (IsSliceInBounds (Const32 [c]) (Const32 [d])) => (ConstBool [0 <= c && c <= d])
263 (IsSliceInBounds (Const64 [c]) (Const64 [d])) => (ConstBool [0 <= c && c <= d])
264 (IsSliceInBounds (SliceLen x) (SliceCap x)) => (ConstBool [true])
265
266 (Eq(64|32|16|8) x x) => (ConstBool [true])
267 (EqB (ConstBool [c]) (ConstBool [d])) => (ConstBool [c == d])
268 (EqB (ConstBool [false]) x) => (Not x)
269 (EqB (ConstBool [true]) x) => x
270
271 (Neq(64|32|16|8) x x) => (ConstBool [false])
272 (NeqB (ConstBool [c]) (ConstBool [d])) => (ConstBool [c != d])
273 (NeqB (ConstBool [false]) x) => x
274 (NeqB (ConstBool [true]) x) => (Not x)
275 (NeqB (Not x) (Not y)) => (NeqB x y)
276
277 (Eq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Eq64 (Const64 <t> [c-d]) x)
278 (Eq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Eq32 (Const32 <t> [c-d]) x)
279 (Eq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Eq16 (Const16 <t> [c-d]) x)
280 (Eq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Eq8 (Const8 <t> [c-d]) x)
281
282 (Neq64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Neq64 (Const64 <t> [c-d]) x)
283 (Neq32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Neq32 (Const32 <t> [c-d]) x)
284 (Neq16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Neq16 (Const16 <t> [c-d]) x)
285 (Neq8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Neq8 (Const8 <t> [c-d]) x)
286
287 // signed integer range: ( c <= x && x (<|<=) d ) -> ( unsigned(x-c) (<|<=) unsigned(d-c) )
288 (AndB (Leq64 (Const64 [c]) x) ((Less|Leq)64 x (Const64 [d]))) && d >= c => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c])) (Const64 <x.Type> [d-c]))
289 (AndB (Leq32 (Const32 [c]) x) ((Less|Leq)32 x (Const32 [d]))) && d >= c => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c])) (Const32 <x.Type> [d-c]))
290 (AndB (Leq16 (Const16 [c]) x) ((Less|Leq)16 x (Const16 [d]))) && d >= c => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c])) (Const16 <x.Type> [d-c]))
291 (AndB (Leq8 (Const8 [c]) x) ((Less|Leq)8 x (Const8 [d]))) && d >= c => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c])) (Const8 <x.Type> [d-c]))
292
293 // signed integer range: ( c < x && x (<|<=) d ) -> ( unsigned(x-(c+1)) (<|<=) unsigned(d-(c+1)) )
294 (AndB (Less64 (Const64 [c]) x) ((Less|Leq)64 x (Const64 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c+1])) (Const64 <x.Type> [d-c-1]))
295 (AndB (Less32 (Const32 [c]) x) ((Less|Leq)32 x (Const32 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c+1])) (Const32 <x.Type> [d-c-1]))
296 (AndB (Less16 (Const16 [c]) x) ((Less|Leq)16 x (Const16 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c+1])) (Const16 <x.Type> [d-c-1]))
297 (AndB (Less8 (Const8 [c]) x) ((Less|Leq)8 x (Const8 [d]))) && d >= c+1 && c+1 > c => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c+1])) (Const8 <x.Type> [d-c-1]))
298
299 // unsigned integer range: ( c <= x && x (<|<=) d ) -> ( x-c (<|<=) d-c )
300 (AndB (Leq64U (Const64 [c]) x) ((Less|Leq)64U x (Const64 [d]))) && uint64(d) >= uint64(c) => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c])) (Const64 <x.Type> [d-c]))
301 (AndB (Leq32U (Const32 [c]) x) ((Less|Leq)32U x (Const32 [d]))) && uint32(d) >= uint32(c) => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c])) (Const32 <x.Type> [d-c]))
302 (AndB (Leq16U (Const16 [c]) x) ((Less|Leq)16U x (Const16 [d]))) && uint16(d) >= uint16(c) => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c])) (Const16 <x.Type> [d-c]))
303 (AndB (Leq8U (Const8 [c]) x) ((Less|Leq)8U x (Const8 [d]))) && uint8(d) >= uint8(c) => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c])) (Const8 <x.Type> [d-c]))
304
305 // unsigned integer range: ( c < x && x (<|<=) d ) -> ( x-(c+1) (<|<=) d-(c+1) )
306 (AndB (Less64U (Const64 [c]) x) ((Less|Leq)64U x (Const64 [d]))) && uint64(d) >= uint64(c+1) && uint64(c+1) > uint64(c) => ((Less|Leq)64U (Sub64 <x.Type> x (Const64 <x.Type> [c+1])) (Const64 <x.Type> [d-c-1]))
307 (AndB (Less32U (Const32 [c]) x) ((Less|Leq)32U x (Const32 [d]))) && uint32(d) >= uint32(c+1) && uint32(c+1) > uint32(c) => ((Less|Leq)32U (Sub32 <x.Type> x (Const32 <x.Type> [c+1])) (Const32 <x.Type> [d-c-1]))
308 (AndB (Less16U (Const16 [c]) x) ((Less|Leq)16U x (Const16 [d]))) && uint16(d) >= uint16(c+1) && uint16(c+1) > uint16(c) => ((Less|Leq)16U (Sub16 <x.Type> x (Const16 <x.Type> [c+1])) (Const16 <x.Type> [d-c-1]))
309 (AndB (Less8U (Const8 [c]) x) ((Less|Leq)8U x (Const8 [d]))) && uint8(d) >= uint8(c+1) && uint8(c+1) > uint8(c) => ((Less|Leq)8U (Sub8 <x.Type> x (Const8 <x.Type> [c+1])) (Const8 <x.Type> [d-c-1]))
310
311 // signed integer range: ( c (<|<=) x || x < d ) -> ( unsigned(c-d) (<|<=) unsigned(x-d) )
312 (OrB ((Less|Leq)64 (Const64 [c]) x) (Less64 x (Const64 [d]))) && c >= d => ((Less|Leq)64U (Const64 <x.Type> [c-d]) (Sub64 <x.Type> x (Const64 <x.Type> [d])))
313 (OrB ((Less|Leq)32 (Const32 [c]) x) (Less32 x (Const32 [d]))) && c >= d => ((Less|Leq)32U (Const32 <x.Type> [c-d]) (Sub32 <x.Type> x (Const32 <x.Type> [d])))
314 (OrB ((Less|Leq)16 (Const16 [c]) x) (Less16 x (Const16 [d]))) && c >= d => ((Less|Leq)16U (Const16 <x.Type> [c-d]) (Sub16 <x.Type> x (Const16 <x.Type> [d])))
315 (OrB ((Less|Leq)8 (Const8 [c]) x) (Less8 x (Const8 [d]))) && c >= d => ((Less|Leq)8U (Const8 <x.Type> [c-d]) (Sub8 <x.Type> x (Const8 <x.Type> [d])))
316
317 // signed integer range: ( c (<|<=) x || x <= d ) -> ( unsigned(c-(d+1)) (<|<=) unsigned(x-(d+1)) )
318 (OrB ((Less|Leq)64 (Const64 [c]) x) (Leq64 x (Const64 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)64U (Const64 <x.Type> [c-d-1]) (Sub64 <x.Type> x (Const64 <x.Type> [d+1])))
319 (OrB ((Less|Leq)32 (Const32 [c]) x) (Leq32 x (Const32 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)32U (Const32 <x.Type> [c-d-1]) (Sub32 <x.Type> x (Const32 <x.Type> [d+1])))
320 (OrB ((Less|Leq)16 (Const16 [c]) x) (Leq16 x (Const16 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)16U (Const16 <x.Type> [c-d-1]) (Sub16 <x.Type> x (Const16 <x.Type> [d+1])))
321 (OrB ((Less|Leq)8 (Const8 [c]) x) (Leq8 x (Const8 [d]))) && c >= d+1 && d+1 > d => ((Less|Leq)8U (Const8 <x.Type> [c-d-1]) (Sub8 <x.Type> x (Const8 <x.Type> [d+1])))
322
323 // unsigned integer range: ( c (<|<=) x || x < d ) -> ( c-d (<|<=) x-d )
324 (OrB ((Less|Leq)64U (Const64 [c]) x) (Less64U x (Const64 [d]))) && uint64(c) >= uint64(d) => ((Less|Leq)64U (Const64 <x.Type> [c-d]) (Sub64 <x.Type> x (Const64 <x.Type> [d])))
325 (OrB ((Less|Leq)32U (Const32 [c]) x) (Less32U x (Const32 [d]))) && uint32(c) >= uint32(d) => ((Less|Leq)32U (Const32 <x.Type> [c-d]) (Sub32 <x.Type> x (Const32 <x.Type> [d])))
326 (OrB ((Less|Leq)16U (Const16 [c]) x) (Less16U x (Const16 [d]))) && uint16(c) >= uint16(d) => ((Less|Leq)16U (Const16 <x.Type> [c-d]) (Sub16 <x.Type> x (Const16 <x.Type> [d])))
327 (OrB ((Less|Leq)8U (Const8 [c]) x) (Less8U x (Const8 [d]))) && uint8(c) >= uint8(d) => ((Less|Leq)8U (Const8 <x.Type> [c-d]) (Sub8 <x.Type> x (Const8 <x.Type> [d])))
328
329 // unsigned integer range: ( c (<|<=) x || x <= d ) -> ( c-(d+1) (<|<=) x-(d+1) )
330 (OrB ((Less|Leq)64U (Const64 [c]) x) (Leq64U x (Const64 [d]))) && uint64(c) >= uint64(d+1) && uint64(d+1) > uint64(d) => ((Less|Leq)64U (Const64 <x.Type> [c-d-1]) (Sub64 <x.Type> x (Const64 <x.Type> [d+1])))
331 (OrB ((Less|Leq)32U (Const32 [c]) x) (Leq32U x (Const32 [d]))) && uint32(c) >= uint32(d+1) && uint32(d+1) > uint32(d) => ((Less|Leq)32U (Const32 <x.Type> [c-d-1]) (Sub32 <x.Type> x (Const32 <x.Type> [d+1])))
332 (OrB ((Less|Leq)16U (Const16 [c]) x) (Leq16U x (Const16 [d]))) && uint16(c) >= uint16(d+1) && uint16(d+1) > uint16(d) => ((Less|Leq)16U (Const16 <x.Type> [c-d-1]) (Sub16 <x.Type> x (Const16 <x.Type> [d+1])))
333 (OrB ((Less|Leq)8U (Const8 [c]) x) (Leq8U x (Const8 [d]))) && uint8(c) >= uint8(d+1) && uint8(d+1) > uint8(d) => ((Less|Leq)8U (Const8 <x.Type> [c-d-1]) (Sub8 <x.Type> x (Const8 <x.Type> [d+1])))
334
335 // Canonicalize x-const to x+(-const)
336 (Sub64 x (Const64 <t> [c])) && x.Op != OpConst64 => (Add64 (Const64 <t> [-c]) x)
337 (Sub32 x (Const32 <t> [c])) && x.Op != OpConst32 => (Add32 (Const32 <t> [-c]) x)
338 (Sub16 x (Const16 <t> [c])) && x.Op != OpConst16 => (Add16 (Const16 <t> [-c]) x)
339 (Sub8 x (Const8 <t> [c])) && x.Op != OpConst8 => (Add8 (Const8 <t> [-c]) x)
340
341 // fold negation into comparison operators
342 (Not (Eq(64|32|16|8|B|Ptr|64F|32F) x y)) => (Neq(64|32|16|8|B|Ptr|64F|32F) x y)
343 (Not (Neq(64|32|16|8|B|Ptr|64F|32F) x y)) => (Eq(64|32|16|8|B|Ptr|64F|32F) x y)
344
345 (Not (Less(64|32|16|8) x y)) => (Leq(64|32|16|8) y x)
346 (Not (Less(64|32|16|8)U x y)) => (Leq(64|32|16|8)U y x)
347 (Not (Leq(64|32|16|8) x y)) => (Less(64|32|16|8) y x)
348 (Not (Leq(64|32|16|8)U x y)) => (Less(64|32|16|8)U y x)
349
350 // Distribute multiplication c * (d+x) -> c*d + c*x. Useful for:
351 // a[i].b = ...; a[i+1].b = ...
352 (Mul64 (Const64 <t> [c]) (Add64 <t> (Const64 <t> [d]) x)) =>
353 (Add64 (Const64 <t> [c*d]) (Mul64 <t> (Const64 <t> [c]) x))
354 (Mul32 (Const32 <t> [c]) (Add32 <t> (Const32 <t> [d]) x)) =>
355 (Add32 (Const32 <t> [c*d]) (Mul32 <t> (Const32 <t> [c]) x))
356
357 // Rewrite x*y ± x*z to x*(y±z)
358 (Add(64|32|16|8) <t> (Mul(64|32|16|8) x y) (Mul(64|32|16|8) x z))
359 => (Mul(64|32|16|8) x (Add(64|32|16|8) <t> y z))
360 (Sub(64|32|16|8) <t> (Mul(64|32|16|8) x y) (Mul(64|32|16|8) x z))
361 => (Mul(64|32|16|8) x (Sub(64|32|16|8) <t> y z))
362
363 // rewrite shifts of 8/16/32 bit consts into 64 bit consts to reduce
364 // the number of the other rewrite rules for const shifts
365 (Lsh64x32 <t> x (Const32 [c])) => (Lsh64x64 x (Const64 <t> [int64(uint32(c))]))
366 (Lsh64x16 <t> x (Const16 [c])) => (Lsh64x64 x (Const64 <t> [int64(uint16(c))]))
367 (Lsh64x8 <t> x (Const8 [c])) => (Lsh64x64 x (Const64 <t> [int64(uint8(c))]))
368 (Rsh64x32 <t> x (Const32 [c])) => (Rsh64x64 x (Const64 <t> [int64(uint32(c))]))
369 (Rsh64x16 <t> x (Const16 [c])) => (Rsh64x64 x (Const64 <t> [int64(uint16(c))]))
370 (Rsh64x8 <t> x (Const8 [c])) => (Rsh64x64 x (Const64 <t> [int64(uint8(c))]))
371 (Rsh64Ux32 <t> x (Const32 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint32(c))]))
372 (Rsh64Ux16 <t> x (Const16 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint16(c))]))
373 (Rsh64Ux8 <t> x (Const8 [c])) => (Rsh64Ux64 x (Const64 <t> [int64(uint8(c))]))
374
375 (Lsh32x32 <t> x (Const32 [c])) => (Lsh32x64 x (Const64 <t> [int64(uint32(c))]))
376 (Lsh32x16 <t> x (Const16 [c])) => (Lsh32x64 x (Const64 <t> [int64(uint16(c))]))
377 (Lsh32x8 <t> x (Const8 [c])) => (Lsh32x64 x (Const64 <t> [int64(uint8(c))]))
378 (Rsh32x32 <t> x (Const32 [c])) => (Rsh32x64 x (Const64 <t> [int64(uint32(c))]))
379 (Rsh32x16 <t> x (Const16 [c])) => (Rsh32x64 x (Const64 <t> [int64(uint16(c))]))
380 (Rsh32x8 <t> x (Const8 [c])) => (Rsh32x64 x (Const64 <t> [int64(uint8(c))]))
381 (Rsh32Ux32 <t> x (Const32 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint32(c))]))
382 (Rsh32Ux16 <t> x (Const16 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint16(c))]))
383 (Rsh32Ux8 <t> x (Const8 [c])) => (Rsh32Ux64 x (Const64 <t> [int64(uint8(c))]))
384
385 (Lsh16x32 <t> x (Const32 [c])) => (Lsh16x64 x (Const64 <t> [int64(uint32(c))]))
386 (Lsh16x16 <t> x (Const16 [c])) => (Lsh16x64 x (Const64 <t> [int64(uint16(c))]))
387 (Lsh16x8 <t> x (Const8 [c])) => (Lsh16x64 x (Const64 <t> [int64(uint8(c))]))
388 (Rsh16x32 <t> x (Const32 [c])) => (Rsh16x64 x (Const64 <t> [int64(uint32(c))]))
389 (Rsh16x16 <t> x (Const16 [c])) => (Rsh16x64 x (Const64 <t> [int64(uint16(c))]))
390 (Rsh16x8 <t> x (Const8 [c])) => (Rsh16x64 x (Const64 <t> [int64(uint8(c))]))
391 (Rsh16Ux32 <t> x (Const32 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint32(c))]))
392 (Rsh16Ux16 <t> x (Const16 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint16(c))]))
393 (Rsh16Ux8 <t> x (Const8 [c])) => (Rsh16Ux64 x (Const64 <t> [int64(uint8(c))]))
394
395 (Lsh8x32 <t> x (Const32 [c])) => (Lsh8x64 x (Const64 <t> [int64(uint32(c))]))
396 (Lsh8x16 <t> x (Const16 [c])) => (Lsh8x64 x (Const64 <t> [int64(uint16(c))]))
397 (Lsh8x8 <t> x (Const8 [c])) => (Lsh8x64 x (Const64 <t> [int64(uint8(c))]))
398 (Rsh8x32 <t> x (Const32 [c])) => (Rsh8x64 x (Const64 <t> [int64(uint32(c))]))
399 (Rsh8x16 <t> x (Const16 [c])) => (Rsh8x64 x (Const64 <t> [int64(uint16(c))]))
400 (Rsh8x8 <t> x (Const8 [c])) => (Rsh8x64 x (Const64 <t> [int64(uint8(c))]))
401 (Rsh8Ux32 <t> x (Const32 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint32(c))]))
402 (Rsh8Ux16 <t> x (Const16 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint16(c))]))
403 (Rsh8Ux8 <t> x (Const8 [c])) => (Rsh8Ux64 x (Const64 <t> [int64(uint8(c))]))
404
405 // shifts by zero
406 (Lsh(64|32|16|8)x64 x (Const64 [0])) => x
407 (Rsh(64|32|16|8)x64 x (Const64 [0])) => x
408 (Rsh(64|32|16|8)Ux64 x (Const64 [0])) => x
409
410 // rotates by multiples of register width
411 (RotateLeft64 x (Const64 [c])) && c%64 == 0 => x
412 (RotateLeft32 x (Const32 [c])) && c%32 == 0 => x
413 (RotateLeft16 x (Const16 [c])) && c%16 == 0 => x
414 (RotateLeft8 x (Const8 [c])) && c%8 == 0 => x
415
416 // zero shifted
417 (Lsh64x(64|32|16|8) (Const64 [0]) _) => (Const64 [0])
418 (Rsh64x(64|32|16|8) (Const64 [0]) _) => (Const64 [0])
419 (Rsh64Ux(64|32|16|8) (Const64 [0]) _) => (Const64 [0])
420 (Lsh32x(64|32|16|8) (Const32 [0]) _) => (Const32 [0])
421 (Rsh32x(64|32|16|8) (Const32 [0]) _) => (Const32 [0])
422 (Rsh32Ux(64|32|16|8) (Const32 [0]) _) => (Const32 [0])
423 (Lsh16x(64|32|16|8) (Const16 [0]) _) => (Const16 [0])
424 (Rsh16x(64|32|16|8) (Const16 [0]) _) => (Const16 [0])
425 (Rsh16Ux(64|32|16|8) (Const16 [0]) _) => (Const16 [0])
426 (Lsh8x(64|32|16|8) (Const8 [0]) _) => (Const8 [0])
427 (Rsh8x(64|32|16|8) (Const8 [0]) _) => (Const8 [0])
428 (Rsh8Ux(64|32|16|8) (Const8 [0]) _) => (Const8 [0])
429
430 // large left shifts of all values, and right shifts of unsigned values
431 ((Lsh64|Rsh64U)x64 _ (Const64 [c])) && uint64(c) >= 64 => (Const64 [0])
432 ((Lsh32|Rsh32U)x64 _ (Const64 [c])) && uint64(c) >= 32 => (Const32 [0])
433 ((Lsh16|Rsh16U)x64 _ (Const64 [c])) && uint64(c) >= 16 => (Const16 [0])
434 ((Lsh8|Rsh8U)x64 _ (Const64 [c])) && uint64(c) >= 8 => (Const8 [0])
435
436 // combine const shifts
437 (Lsh64x64 <t> (Lsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh64x64 x (Const64 <t> [c+d]))
438 (Lsh32x64 <t> (Lsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh32x64 x (Const64 <t> [c+d]))
439 (Lsh16x64 <t> (Lsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh16x64 x (Const64 <t> [c+d]))
440 (Lsh8x64 <t> (Lsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Lsh8x64 x (Const64 <t> [c+d]))
441
442 (Rsh64x64 <t> (Rsh64x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh64x64 x (Const64 <t> [c+d]))
443 (Rsh32x64 <t> (Rsh32x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh32x64 x (Const64 <t> [c+d]))
444 (Rsh16x64 <t> (Rsh16x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh16x64 x (Const64 <t> [c+d]))
445 (Rsh8x64 <t> (Rsh8x64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh8x64 x (Const64 <t> [c+d]))
446
447 (Rsh64Ux64 <t> (Rsh64Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh64Ux64 x (Const64 <t> [c+d]))
448 (Rsh32Ux64 <t> (Rsh32Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh32Ux64 x (Const64 <t> [c+d]))
449 (Rsh16Ux64 <t> (Rsh16Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh16Ux64 x (Const64 <t> [c+d]))
450 (Rsh8Ux64 <t> (Rsh8Ux64 x (Const64 [c])) (Const64 [d])) && !uaddOvf(c,d) => (Rsh8Ux64 x (Const64 <t> [c+d]))
451
452 // Remove signed right shift before an unsigned right shift that extracts the sign bit.
453 (Rsh8Ux64 (Rsh8x64 x _) (Const64 <t> [7] )) => (Rsh8Ux64 x (Const64 <t> [7] ))
454 (Rsh16Ux64 (Rsh16x64 x _) (Const64 <t> [15])) => (Rsh16Ux64 x (Const64 <t> [15]))
455 (Rsh32Ux64 (Rsh32x64 x _) (Const64 <t> [31])) => (Rsh32Ux64 x (Const64 <t> [31]))
456 (Rsh64Ux64 (Rsh64x64 x _) (Const64 <t> [63])) => (Rsh64Ux64 x (Const64 <t> [63]))
457
458 // Convert x>>c<<c to x&^(1<<c-1)
459 (Lsh64x64 i:(Rsh(64|64U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 64 && i.Uses == 1 => (And64 x (Const64 <v.Type> [int64(-1) << c]))
460 (Lsh32x64 i:(Rsh(32|32U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 32 && i.Uses == 1 => (And32 x (Const32 <v.Type> [int32(-1) << c]))
461 (Lsh16x64 i:(Rsh(16|16U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 16 && i.Uses == 1 => (And16 x (Const16 <v.Type> [int16(-1) << c]))
462 (Lsh8x64 i:(Rsh(8|8U)x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 8 && i.Uses == 1 => (And8 x (Const8 <v.Type> [int8(-1) << c]))
463 // similarly for x<<c>>c
464 (Rsh64Ux64 i:(Lsh64x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 64 && i.Uses == 1 => (And64 x (Const64 <v.Type> [int64(^uint64(0)>>c)]))
465 (Rsh32Ux64 i:(Lsh32x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 32 && i.Uses == 1 => (And32 x (Const32 <v.Type> [int32(^uint32(0)>>c)]))
466 (Rsh16Ux64 i:(Lsh16x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 16 && i.Uses == 1 => (And16 x (Const16 <v.Type> [int16(^uint16(0)>>c)]))
467 (Rsh8Ux64 i:(Lsh8x64 x (Const64 [c])) (Const64 [c])) && c >= 0 && c < 8 && i.Uses == 1 => (And8 x (Const8 <v.Type> [int8 (^uint8 (0)>>c)]))
468
469 // ((x >> c1) << c2) >> c3
470 (Rsh(64|32|16|8)Ux64 (Lsh(64|32|16|8)x64 (Rsh(64|32|16|8)Ux64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
471 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3)
472 => (Rsh(64|32|16|8)Ux64 x (Const64 <typ.UInt64> [c1-c2+c3]))
473
474 // ((x << c1) >> c2) << c3
475 (Lsh(64|32|16|8)x64 (Rsh(64|32|16|8)Ux64 (Lsh(64|32|16|8)x64 x (Const64 [c1])) (Const64 [c2])) (Const64 [c3]))
476 && uint64(c1) >= uint64(c2) && uint64(c3) >= uint64(c2) && !uaddOvf(c1-c2, c3)
477 => (Lsh(64|32|16|8)x64 x (Const64 <typ.UInt64> [c1-c2+c3]))
478
479 // (x >> c) & uppermask = 0
480 (And64 (Const64 [m]) (Rsh64Ux64 _ (Const64 [c]))) && c >= int64(64-ntz64(m)) => (Const64 [0])
481 (And32 (Const32 [m]) (Rsh32Ux64 _ (Const64 [c]))) && c >= int64(32-ntz32(m)) => (Const32 [0])
482 (And16 (Const16 [m]) (Rsh16Ux64 _ (Const64 [c]))) && c >= int64(16-ntz16(m)) => (Const16 [0])
483 (And8 (Const8 [m]) (Rsh8Ux64 _ (Const64 [c]))) && c >= int64(8-ntz8(m)) => (Const8 [0])
484
485 // (x << c) & lowermask = 0
486 (And64 (Const64 [m]) (Lsh64x64 _ (Const64 [c]))) && c >= int64(64-nlz64(m)) => (Const64 [0])
487 (And32 (Const32 [m]) (Lsh32x64 _ (Const64 [c]))) && c >= int64(32-nlz32(m)) => (Const32 [0])
488 (And16 (Const16 [m]) (Lsh16x64 _ (Const64 [c]))) && c >= int64(16-nlz16(m)) => (Const16 [0])
489 (And8 (Const8 [m]) (Lsh8x64 _ (Const64 [c]))) && c >= int64(8-nlz8(m)) => (Const8 [0])
490
491 // replace shifts with zero extensions
492 (Rsh16Ux64 (Lsh16x64 x (Const64 [8])) (Const64 [8])) => (ZeroExt8to16 (Trunc16to8 <typ.UInt8> x))
493 (Rsh32Ux64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) => (ZeroExt8to32 (Trunc32to8 <typ.UInt8> x))
494 (Rsh64Ux64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) => (ZeroExt8to64 (Trunc64to8 <typ.UInt8> x))
495 (Rsh32Ux64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) => (ZeroExt16to32 (Trunc32to16 <typ.UInt16> x))
496 (Rsh64Ux64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) => (ZeroExt16to64 (Trunc64to16 <typ.UInt16> x))
497 (Rsh64Ux64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) => (ZeroExt32to64 (Trunc64to32 <typ.UInt32> x))
498
499 // replace shifts with sign extensions
500 (Rsh16x64 (Lsh16x64 x (Const64 [8])) (Const64 [8])) => (SignExt8to16 (Trunc16to8 <typ.Int8> x))
501 (Rsh32x64 (Lsh32x64 x (Const64 [24])) (Const64 [24])) => (SignExt8to32 (Trunc32to8 <typ.Int8> x))
502 (Rsh64x64 (Lsh64x64 x (Const64 [56])) (Const64 [56])) => (SignExt8to64 (Trunc64to8 <typ.Int8> x))
503 (Rsh32x64 (Lsh32x64 x (Const64 [16])) (Const64 [16])) => (SignExt16to32 (Trunc32to16 <typ.Int16> x))
504 (Rsh64x64 (Lsh64x64 x (Const64 [48])) (Const64 [48])) => (SignExt16to64 (Trunc64to16 <typ.Int16> x))
505 (Rsh64x64 (Lsh64x64 x (Const64 [32])) (Const64 [32])) => (SignExt32to64 (Trunc64to32 <typ.Int32> x))
506
507 // ((x >> c) & d) << e
508 (Lsh64x64 (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c])) (Const64 [d])) (Const64 [e])) && c >= e => (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c-e])) (Const64 <t> [d<<e]))
509 (Lsh32x64 (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c])) (Const32 [d])) (Const64 [e])) && c >= e => (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c-e])) (Const32 <t> [d<<e]))
510 (Lsh16x64 (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c])) (Const16 [d])) (Const64 [e])) && c >= e => (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c-e])) (Const16 <t> [d<<e]))
511 (Lsh8x64 (And8 (Rsh(8|8U)x64 <t> x (Const64 <t2> [c])) (Const8 [d])) (Const64 [e])) && c >= e => (And8 (Rsh(8|8U)x64 <t> x (Const64 <t2> [c-e])) (Const8 <t> [d<<e]))
512 (Lsh64x64 (And64 (Rsh(64|64U)x64 <t> x (Const64 <t2> [c])) (Const64 [d])) (Const64 [e])) && c < e => (And64 (Lsh64x64 <t> x (Const64 <t2> [e-c])) (Const64 <t> [d<<e]))
513 (Lsh32x64 (And32 (Rsh(32|32U)x64 <t> x (Const64 <t2> [c])) (Const32 [d])) (Const64 [e])) && c < e => (And32 (Lsh32x64 <t> x (Const64 <t2> [e-c])) (Const32 <t> [d<<e]))
514 (Lsh16x64 (And16 (Rsh(16|16U)x64 <t> x (Const64 <t2> [c])) (Const16 [d])) (Const64 [e])) && c < e => (And16 (Lsh16x64 <t> x (Const64 <t2> [e-c])) (Const16 <t> [d<<e]))
515 (Lsh8x64 (And8 (Rsh(8|8U)x64 <t> x (Const64 <t2> [c])) (Const8 [d])) (Const64 [e])) && c < e => (And8 (Lsh8x64 <t> x (Const64 <t2> [e-c])) (Const8 <t> [d<<e]))
516
517 // constant comparisons
518 (Eq(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c == d])
519 (Neq(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c != d])
520 (Less(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c < d])
521 (Leq(64|32|16|8) (Const(64|32|16|8) [c]) (Const(64|32|16|8) [d])) => (ConstBool [c <= d])
522
523 (Less64U (Const64 [c]) (Const64 [d])) => (ConstBool [uint64(c) < uint64(d)])
524 (Less32U (Const32 [c]) (Const32 [d])) => (ConstBool [uint32(c) < uint32(d)])
525 (Less16U (Const16 [c]) (Const16 [d])) => (ConstBool [uint16(c) < uint16(d)])
526 (Less8U (Const8 [c]) (Const8 [d])) => (ConstBool [ uint8(c) < uint8(d)])
527
528 (Leq64U (Const64 [c]) (Const64 [d])) => (ConstBool [uint64(c) <= uint64(d)])
529 (Leq32U (Const32 [c]) (Const32 [d])) => (ConstBool [uint32(c) <= uint32(d)])
530 (Leq16U (Const16 [c]) (Const16 [d])) => (ConstBool [uint16(c) <= uint16(d)])
531 (Leq8U (Const8 [c]) (Const8 [d])) => (ConstBool [ uint8(c) <= uint8(d)])
532
533 (Leq8 (Const8 [0]) (And8 _ (Const8 [c]))) && c >= 0 => (ConstBool [true])
534 (Leq16 (Const16 [0]) (And16 _ (Const16 [c]))) && c >= 0 => (ConstBool [true])
535 (Leq32 (Const32 [0]) (And32 _ (Const32 [c]))) && c >= 0 => (ConstBool [true])
536 (Leq64 (Const64 [0]) (And64 _ (Const64 [c]))) && c >= 0 => (ConstBool [true])
537
538 (Leq8 (Const8 [0]) (Rsh8Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
539 (Leq16 (Const16 [0]) (Rsh16Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
540 (Leq32 (Const32 [0]) (Rsh32Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
541 (Leq64 (Const64 [0]) (Rsh64Ux64 _ (Const64 [c]))) && c > 0 => (ConstBool [true])
542
543 // prefer equalities with zero
544 (Less(64|32|16|8) (Const(64|32|16|8) <t> [0]) x) && isNonNegative(x) => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
545 (Less(64|32|16|8) x (Const(64|32|16|8) <t> [1])) && isNonNegative(x) => (Eq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
546 (Less(64|32|16|8)U x (Const(64|32|16|8) <t> [1])) => (Eq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
547 (Leq(64|32|16|8)U (Const(64|32|16|8) <t> [1]) x) => (Neq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
548
549 // prefer comparisons with zero
550 (Less(64|32|16|8) x (Const(64|32|16|8) <t> [1])) => (Leq(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
551 (Leq(64|32|16|8) x (Const(64|32|16|8) <t> [-1])) => (Less(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
552 (Leq(64|32|16|8) (Const(64|32|16|8) <t> [1]) x) => (Less(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
553 (Less(64|32|16|8) (Const(64|32|16|8) <t> [-1]) x) => (Leq(64|32|16|8) (Const(64|32|16|8) <t> [0]) x)
554
555 // constant floating point comparisons
556 (Eq32F (Const32F [c]) (Const32F [d])) => (ConstBool [c == d])
557 (Eq64F (Const64F [c]) (Const64F [d])) => (ConstBool [c == d])
558 (Neq32F (Const32F [c]) (Const32F [d])) => (ConstBool [c != d])
559 (Neq64F (Const64F [c]) (Const64F [d])) => (ConstBool [c != d])
560 (Less32F (Const32F [c]) (Const32F [d])) => (ConstBool [c < d])
561 (Less64F (Const64F [c]) (Const64F [d])) => (ConstBool [c < d])
562 (Leq32F (Const32F [c]) (Const32F [d])) => (ConstBool [c <= d])
563 (Leq64F (Const64F [c]) (Const64F [d])) => (ConstBool [c <= d])
564
565 // simplifications
566 (Or(64|32|16|8) x x) => x
567 (Or(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
568 (Or(64|32|16|8) (Const(64|32|16|8) [-1]) _) => (Const(64|32|16|8) [-1])
569 (Or(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [-1])
570
571 (And(64|32|16|8) x x) => x
572 (And(64|32|16|8) (Const(64|32|16|8) [-1]) x) => x
573 (And(64|32|16|8) (Const(64|32|16|8) [0]) _) => (Const(64|32|16|8) [0])
574 (And(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [0])
575
576 (Xor(64|32|16|8) x x) => (Const(64|32|16|8) [0])
577 (Xor(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
578 (Xor(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [-1])
579
580 (Add(64|32|16|8) (Const(64|32|16|8) [0]) x) => x
581 (Sub(64|32|16|8) x x) => (Const(64|32|16|8) [0])
582 (Mul(64|32|16|8) (Const(64|32|16|8) [0]) _) => (Const(64|32|16|8) [0])
583 (Select0 (Mul(64|32)uover (Const(64|32) [0]) x)) => (Const(64|32) [0])
584 (Select1 (Mul(64|32)uover (Const(64|32) [0]) x)) => (ConstBool [false])
585
586 (Com(64|32|16|8) (Com(64|32|16|8) x)) => x
587 (Com(64|32|16|8) (Const(64|32|16|8) [c])) => (Const(64|32|16|8) [^c])
588
589 (Neg(64|32|16|8) (Sub(64|32|16|8) x y)) => (Sub(64|32|16|8) y x)
590 (Add(64|32|16|8) x (Neg(64|32|16|8) y)) => (Sub(64|32|16|8) x y)
591
592 (Xor(64|32|16|8) (Const(64|32|16|8) [-1]) x) => (Com(64|32|16|8) x)
593
594 (Sub(64|32|16|8) (Neg(64|32|16|8) x) (Com(64|32|16|8) x)) => (Const(64|32|16|8) [1])
595 (Sub(64|32|16|8) (Com(64|32|16|8) x) (Neg(64|32|16|8) x)) => (Const(64|32|16|8) [-1])
596 (Add(64|32|16|8) (Com(64|32|16|8) x) x) => (Const(64|32|16|8) [-1])
597
598 // Simplification when involving common integer
599 // (t + x) - (t + y) == x - y
600 // (t + x) - (y + t) == x - y
601 // (x + t) - (y + t) == x - y
602 // (x + t) - (t + y) == x - y
603 // (x - t) + (t + y) == x + y
604 // (x - t) + (y + t) == x + y
605 (Sub(64|32|16|8) (Add(64|32|16|8) t x) (Add(64|32|16|8) t y)) => (Sub(64|32|16|8) x y)
606 (Add(64|32|16|8) (Sub(64|32|16|8) x t) (Add(64|32|16|8) t y)) => (Add(64|32|16|8) x y)
607
608 // ^(x-1) == ^x+1 == -x
609 (Add(64|32|16|8) (Const(64|32|16|8) [1]) (Com(64|32|16|8) x)) => (Neg(64|32|16|8) x)
610 (Com(64|32|16|8) (Add(64|32|16|8) (Const(64|32|16|8) [-1]) x)) => (Neg(64|32|16|8) x)
611
612 // -(-x) == x
613 (Neg(64|32|16|8) (Neg(64|32|16|8) x)) => x
614
615 // -^x == x+1
616 (Neg(64|32|16|8) <t> (Com(64|32|16|8) x)) => (Add(64|32|16|8) (Const(64|32|16|8) <t> [1]) x)
617
618 (And(64|32|16|8) x (And(64|32|16|8) x y)) => (And(64|32|16|8) x y)
619 (Or(64|32|16|8) x (Or(64|32|16|8) x y)) => (Or(64|32|16|8) x y)
620 (Xor(64|32|16|8) x (Xor(64|32|16|8) x y)) => y
621
622 // Fold comparisons with numeric bounds
623 (Less(64|32|16|8)U _ (Const(64|32|16|8) [0])) => (ConstBool [false])
624 (Leq(64|32|16|8)U (Const(64|32|16|8) [0]) _) => (ConstBool [true])
625 (Less(64|32|16|8)U (Const(64|32|16|8) [-1]) _) => (ConstBool [false])
626 (Leq(64|32|16|8)U _ (Const(64|32|16|8) [-1])) => (ConstBool [true])
627 (Less64 _ (Const64 [math.MinInt64])) => (ConstBool [false])
628 (Less32 _ (Const32 [math.MinInt32])) => (ConstBool [false])
629 (Less16 _ (Const16 [math.MinInt16])) => (ConstBool [false])
630 (Less8 _ (Const8 [math.MinInt8 ])) => (ConstBool [false])
631 (Leq64 (Const64 [math.MinInt64]) _) => (ConstBool [true])
632 (Leq32 (Const32 [math.MinInt32]) _) => (ConstBool [true])
633 (Leq16 (Const16 [math.MinInt16]) _) => (ConstBool [true])
634 (Leq8 (Const8 [math.MinInt8 ]) _) => (ConstBool [true])
635 (Less64 (Const64 [math.MaxInt64]) _) => (ConstBool [false])
636 (Less32 (Const32 [math.MaxInt32]) _) => (ConstBool [false])
637 (Less16 (Const16 [math.MaxInt16]) _) => (ConstBool [false])
638 (Less8 (Const8 [math.MaxInt8 ]) _) => (ConstBool [false])
639 (Leq64 _ (Const64 [math.MaxInt64])) => (ConstBool [true])
640 (Leq32 _ (Const32 [math.MaxInt32])) => (ConstBool [true])
641 (Leq16 _ (Const16 [math.MaxInt16])) => (ConstBool [true])
642 (Leq8 _ (Const8 [math.MaxInt8 ])) => (ConstBool [true])
643
644 // Canonicalize <= on numeric bounds and < near numeric bounds to ==
645 (Leq(64|32|16|8)U x c:(Const(64|32|16|8) [0])) => (Eq(64|32|16|8) x c)
646 (Leq(64|32|16|8)U c:(Const(64|32|16|8) [-1]) x) => (Eq(64|32|16|8) x c)
647 (Less(64|32|16|8)U x (Const(64|32|16|8) <t> [1])) => (Eq(64|32|16|8) x (Const(64|32|16|8) <t> [0]))
648 (Less(64|32|16|8)U (Const(64|32|16|8) <t> [-2]) x) => (Eq(64|32|16|8) x (Const(64|32|16|8) <t> [-1]))
649 (Leq64 x c:(Const64 [math.MinInt64])) => (Eq64 x c)
650 (Leq32 x c:(Const32 [math.MinInt32])) => (Eq32 x c)
651 (Leq16 x c:(Const16 [math.MinInt16])) => (Eq16 x c)
652 (Leq8 x c:(Const8 [math.MinInt8 ])) => (Eq8 x c)
653 (Leq64 c:(Const64 [math.MaxInt64]) x) => (Eq64 x c)
654 (Leq32 c:(Const32 [math.MaxInt32]) x) => (Eq32 x c)
655 (Leq16 c:(Const16 [math.MaxInt16]) x) => (Eq16 x c)
656 (Leq8 c:(Const8 [math.MaxInt8 ]) x) => (Eq8 x c)
657 (Less64 x (Const64 <t> [math.MinInt64+1])) => (Eq64 x (Const64 <t> [math.MinInt64]))
658 (Less32 x (Const32 <t> [math.MinInt32+1])) => (Eq32 x (Const32 <t> [math.MinInt32]))
659 (Less16 x (Const16 <t> [math.MinInt16+1])) => (Eq16 x (Const16 <t> [math.MinInt16]))
660 (Less8 x (Const8 <t> [math.MinInt8 +1])) => (Eq8 x (Const8 <t> [math.MinInt8 ]))
661 (Less64 (Const64 <t> [math.MaxInt64-1]) x) => (Eq64 x (Const64 <t> [math.MaxInt64]))
662 (Less32 (Const32 <t> [math.MaxInt32-1]) x) => (Eq32 x (Const32 <t> [math.MaxInt32]))
663 (Less16 (Const16 <t> [math.MaxInt16-1]) x) => (Eq16 x (Const16 <t> [math.MaxInt16]))
664 (Less8 (Const8 <t> [math.MaxInt8 -1]) x) => (Eq8 x (Const8 <t> [math.MaxInt8 ]))
665
666 // Ands clear bits. Ors set bits.
667 // If a subsequent Or will set all the bits
668 // that an And cleared, we can skip the And.
669 // This happens in bitmasking code like:
670 // x &^= 3 << shift // clear two old bits
671 // x |= v << shift // set two new bits
672 // when shift is a small constant and v ends up a constant 3.
673 (Or8 (And8 x (Const8 [c2])) (Const8 <t> [c1])) && ^(c1 | c2) == 0 => (Or8 (Const8 <t> [c1]) x)
674 (Or16 (And16 x (Const16 [c2])) (Const16 <t> [c1])) && ^(c1 | c2) == 0 => (Or16 (Const16 <t> [c1]) x)
675 (Or32 (And32 x (Const32 [c2])) (Const32 <t> [c1])) && ^(c1 | c2) == 0 => (Or32 (Const32 <t> [c1]) x)
676 (Or64 (And64 x (Const64 [c2])) (Const64 <t> [c1])) && ^(c1 | c2) == 0 => (Or64 (Const64 <t> [c1]) x)
677
678 (Trunc64to8 (And64 (Const64 [y]) x)) && y&0xFF == 0xFF => (Trunc64to8 x)
679 (Trunc64to16 (And64 (Const64 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc64to16 x)
680 (Trunc64to32 (And64 (Const64 [y]) x)) && y&0xFFFFFFFF == 0xFFFFFFFF => (Trunc64to32 x)
681 (Trunc32to8 (And32 (Const32 [y]) x)) && y&0xFF == 0xFF => (Trunc32to8 x)
682 (Trunc32to16 (And32 (Const32 [y]) x)) && y&0xFFFF == 0xFFFF => (Trunc32to16 x)
683 (Trunc16to8 (And16 (Const16 [y]) x)) && y&0xFF == 0xFF => (Trunc16to8 x)
684
685 (ZeroExt8to64 (Trunc64to8 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 56 => x
686 (ZeroExt16to64 (Trunc64to16 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 48 => x
687 (ZeroExt32to64 (Trunc64to32 x:(Rsh64Ux64 _ (Const64 [s])))) && s >= 32 => x
688 (ZeroExt8to32 (Trunc32to8 x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 24 => x
689 (ZeroExt16to32 (Trunc32to16 x:(Rsh32Ux64 _ (Const64 [s])))) && s >= 16 => x
690 (ZeroExt8to16 (Trunc16to8 x:(Rsh16Ux64 _ (Const64 [s])))) && s >= 8 => x
691
692 (SignExt8to64 (Trunc64to8 x:(Rsh64x64 _ (Const64 [s])))) && s >= 56 => x
693 (SignExt16to64 (Trunc64to16 x:(Rsh64x64 _ (Const64 [s])))) && s >= 48 => x
694 (SignExt32to64 (Trunc64to32 x:(Rsh64x64 _ (Const64 [s])))) && s >= 32 => x
695 (SignExt8to32 (Trunc32to8 x:(Rsh32x64 _ (Const64 [s])))) && s >= 24 => x
696 (SignExt16to32 (Trunc32to16 x:(Rsh32x64 _ (Const64 [s])))) && s >= 16 => x
697 (SignExt8to16 (Trunc16to8 x:(Rsh16x64 _ (Const64 [s])))) && s >= 8 => x
698
699 (Slicemask (Const32 [x])) && x > 0 => (Const32 [-1])
700 (Slicemask (Const32 [0])) => (Const32 [0])
701 (Slicemask (Const64 [x])) && x > 0 => (Const64 [-1])
702 (Slicemask (Const64 [0])) => (Const64 [0])
703
704 // simplifications often used for lengths. e.g. len(s[i:i+5])==5
705 (Sub(64|32|16|8) (Add(64|32|16|8) x y) x) => y
706 (Sub(64|32|16|8) (Add(64|32|16|8) x y) y) => x
707 (Sub(64|32|16|8) (Sub(64|32|16|8) x y) x) => (Neg(64|32|16|8) y)
708 (Sub(64|32|16|8) x (Add(64|32|16|8) x y)) => (Neg(64|32|16|8) y)
709 (Add(64|32|16|8) x (Sub(64|32|16|8) y x)) => y
710 (Add(64|32|16|8) x (Add(64|32|16|8) y (Sub(64|32|16|8) z x))) => (Add(64|32|16|8) y z)
711
712 // basic phi simplifications
713 (Phi (Const8 [c]) (Const8 [c])) => (Const8 [c])
714 (Phi (Const16 [c]) (Const16 [c])) => (Const16 [c])
715 (Phi (Const32 [c]) (Const32 [c])) => (Const32 [c])
716 (Phi (Const64 [c]) (Const64 [c])) => (Const64 [c])
717
718 // slice and interface comparisons
719 // The frontend ensures that we can only compare against nil,
720 // so we need only compare the first word (interface type or slice ptr).
721 (EqInter x y) => (EqPtr (ITab x) (ITab y))
722 (NeqInter x y) => (NeqPtr (ITab x) (ITab y))
723 (EqSlice x y) => (EqPtr (SlicePtr x) (SlicePtr y))
724 (NeqSlice x y) => (NeqPtr (SlicePtr x) (SlicePtr y))
725
726 // Load of store of same address, with compatibly typed value and same size
727 (Load <t1> p1 (Store {t2} p2 x _))
728 && isSamePtr(p1, p2)
729 && t1.Compare(x.Type) == types.CMPeq
730 && t1.Size() == t2.Size()
731 => x
732 (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 x _)))
733 && isSamePtr(p1, p3)
734 && t1.Compare(x.Type) == types.CMPeq
735 && t1.Size() == t2.Size()
736 && disjoint(p3, t3.Size(), p2, t2.Size())
737 => x
738 (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 x _))))
739 && isSamePtr(p1, p4)
740 && t1.Compare(x.Type) == types.CMPeq
741 && t1.Size() == t2.Size()
742 && disjoint(p4, t4.Size(), p2, t2.Size())
743 && disjoint(p4, t4.Size(), p3, t3.Size())
744 => x
745 (Load <t1> p1 (Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 _ (Store {t5} p5 x _)))))
746 && isSamePtr(p1, p5)
747 && t1.Compare(x.Type) == types.CMPeq
748 && t1.Size() == t2.Size()
749 && disjoint(p5, t5.Size(), p2, t2.Size())
750 && disjoint(p5, t5.Size(), p3, t3.Size())
751 && disjoint(p5, t5.Size(), p4, t4.Size())
752 => x
753
754 // Pass constants through math.Float{32,64}bits and math.Float{32,64}frombits
755 (Load <t1> p1 (Store {t2} p2 (Const64 [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 8 && is64BitFloat(t1) && !math.IsNaN(math.Float64frombits(uint64(x))) => (Const64F [math.Float64frombits(uint64(x))])
756 (Load <t1> p1 (Store {t2} p2 (Const32 [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 4 && is32BitFloat(t1) && !math.IsNaN(float64(math.Float32frombits(uint32(x)))) => (Const32F [math.Float32frombits(uint32(x))])
757 (Load <t1> p1 (Store {t2} p2 (Const64F [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 8 && is64BitInt(t1) => (Const64 [int64(math.Float64bits(x))])
758 (Load <t1> p1 (Store {t2} p2 (Const32F [x]) _)) && isSamePtr(p1,p2) && t2.Size() == 4 && is32BitInt(t1) => (Const32 [int32(math.Float32bits(x))])
759
760 // Float Loads up to Zeros so they can be constant folded.
761 (Load <t1> op:(OffPtr [o1] p1)
762 (Store {t2} p2 _
763 mem:(Zero [n] p3 _)))
764 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p3)
765 && CanSSA(t1)
766 && disjoint(op, t1.Size(), p2, t2.Size())
767 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p3) mem)
768 (Load <t1> op:(OffPtr [o1] p1)
769 (Store {t2} p2 _
770 (Store {t3} p3 _
771 mem:(Zero [n] p4 _))))
772 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p4)
773 && CanSSA(t1)
774 && disjoint(op, t1.Size(), p2, t2.Size())
775 && disjoint(op, t1.Size(), p3, t3.Size())
776 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p4) mem)
777 (Load <t1> op:(OffPtr [o1] p1)
778 (Store {t2} p2 _
779 (Store {t3} p3 _
780 (Store {t4} p4 _
781 mem:(Zero [n] p5 _)))))
782 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p5)
783 && CanSSA(t1)
784 && disjoint(op, t1.Size(), p2, t2.Size())
785 && disjoint(op, t1.Size(), p3, t3.Size())
786 && disjoint(op, t1.Size(), p4, t4.Size())
787 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p5) mem)
788 (Load <t1> op:(OffPtr [o1] p1)
789 (Store {t2} p2 _
790 (Store {t3} p3 _
791 (Store {t4} p4 _
792 (Store {t5} p5 _
793 mem:(Zero [n] p6 _))))))
794 && o1 >= 0 && o1+t1.Size() <= n && isSamePtr(p1, p6)
795 && CanSSA(t1)
796 && disjoint(op, t1.Size(), p2, t2.Size())
797 && disjoint(op, t1.Size(), p3, t3.Size())
798 && disjoint(op, t1.Size(), p4, t4.Size())
799 && disjoint(op, t1.Size(), p5, t5.Size())
800 => @mem.Block (Load <t1> (OffPtr <op.Type> [o1] p6) mem)
801
802 // Zero to Load forwarding.
803 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
804 && t1.IsBoolean()
805 && isSamePtr(p1, p2)
806 && n >= o + 1
807 => (ConstBool [false])
808 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
809 && is8BitInt(t1)
810 && isSamePtr(p1, p2)
811 && n >= o + 1
812 => (Const8 [0])
813 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
814 && is16BitInt(t1)
815 && isSamePtr(p1, p2)
816 && n >= o + 2
817 => (Const16 [0])
818 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
819 && is32BitInt(t1)
820 && isSamePtr(p1, p2)
821 && n >= o + 4
822 => (Const32 [0])
823 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
824 && is64BitInt(t1)
825 && isSamePtr(p1, p2)
826 && n >= o + 8
827 => (Const64 [0])
828 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
829 && is32BitFloat(t1)
830 && isSamePtr(p1, p2)
831 && n >= o + 4
832 => (Const32F [0])
833 (Load <t1> (OffPtr [o] p1) (Zero [n] p2 _))
834 && is64BitFloat(t1)
835 && isSamePtr(p1, p2)
836 && n >= o + 8
837 => (Const64F [0])
838
839 // Eliminate stores of values that have just been loaded from the same location.
840 // We also handle the common case where there are some intermediate stores.
841 (Store {t1} p1 (Load <t2> p2 mem) mem)
842 && isSamePtr(p1, p2)
843 && t2.Size() == t1.Size()
844 => mem
845 (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ oldmem))
846 && isSamePtr(p1, p2)
847 && t2.Size() == t1.Size()
848 && disjoint(p1, t1.Size(), p3, t3.Size())
849 => mem
850 (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ (Store {t4} p4 _ oldmem)))
851 && isSamePtr(p1, p2)
852 && t2.Size() == t1.Size()
853 && disjoint(p1, t1.Size(), p3, t3.Size())
854 && disjoint(p1, t1.Size(), p4, t4.Size())
855 => mem
856 (Store {t1} p1 (Load <t2> p2 oldmem) mem:(Store {t3} p3 _ (Store {t4} p4 _ (Store {t5} p5 _ oldmem))))
857 && isSamePtr(p1, p2)
858 && t2.Size() == t1.Size()
859 && disjoint(p1, t1.Size(), p3, t3.Size())
860 && disjoint(p1, t1.Size(), p4, t4.Size())
861 && disjoint(p1, t1.Size(), p5, t5.Size())
862 => mem
863
864 // Don't Store zeros to cleared variables.
865 (Store {t} (OffPtr [o] p1) x mem:(Zero [n] p2 _))
866 && isConstZero(x)
867 && o >= 0 && t.Size() + o <= n && isSamePtr(p1, p2)
868 => mem
869 (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Zero [n] p3 _)))
870 && isConstZero(x)
871 && o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p3)
872 && disjoint(op, t1.Size(), p2, t2.Size())
873 => mem
874 (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Store {t3} p3 _ (Zero [n] p4 _))))
875 && isConstZero(x)
876 && o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p4)
877 && disjoint(op, t1.Size(), p2, t2.Size())
878 && disjoint(op, t1.Size(), p3, t3.Size())
879 => mem
880 (Store {t1} op:(OffPtr [o1] p1) x mem:(Store {t2} p2 _ (Store {t3} p3 _ (Store {t4} p4 _ (Zero [n] p5 _)))))
881 && isConstZero(x)
882 && o1 >= 0 && t1.Size() + o1 <= n && isSamePtr(p1, p5)
883 && disjoint(op, t1.Size(), p2, t2.Size())
884 && disjoint(op, t1.Size(), p3, t3.Size())
885 && disjoint(op, t1.Size(), p4, t4.Size())
886 => mem
887
888 // Collapse OffPtr
889 (OffPtr (OffPtr p [y]) [x]) => (OffPtr p [x+y])
890 (OffPtr p [0]) && v.Type.Compare(p.Type) == types.CMPeq => p
891
892 // indexing operations
893 // Note: bounds check has already been done
894 (PtrIndex <t> ptr idx) && config.PtrSize == 4 && is32Bit(t.Elem().Size()) => (AddPtr ptr (Mul32 <typ.Int> idx (Const32 <typ.Int> [int32(t.Elem().Size())])))
895 (PtrIndex <t> ptr idx) && config.PtrSize == 8 => (AddPtr ptr (Mul64 <typ.Int> idx (Const64 <typ.Int> [t.Elem().Size()])))
896
897 // struct operations
898 (StructSelect [i] x:(StructMake ___)) => x.Args[i]
899 (Load <t> _ _) && t.IsStruct() && CanSSA(t) => rewriteStructLoad(v)
900 (Store _ (StructMake ___) _) => rewriteStructStore(v)
901
902 (StructSelect [i] x:(Load <t> ptr mem)) && !CanSSA(t) =>
903 @x.Block (Load <v.Type> (OffPtr <v.Type.PtrTo()> [t.FieldOff(int(i))] ptr) mem)
904
905 // Putting struct{*byte} and similar into direct interfaces.
906 (IMake _typ (StructMake val)) => (IMake _typ val)
907 (StructSelect [0] (IData x)) => (IData x)
908
909 // un-SSAable values use mem->mem copies
910 (Store {t} dst (Load src mem) mem) && !CanSSA(t) =>
911 (Move {t} [t.Size()] dst src mem)
912 (Store {t} dst (Load src mem) (VarDef {x} mem)) && !CanSSA(t) =>
913 (Move {t} [t.Size()] dst src (VarDef {x} mem))
914
915 // array ops
916 (ArraySelect (ArrayMake1 x)) => x
917
918 (Load <t> _ _) && t.IsArray() && t.NumElem() == 0 =>
919 (ArrayMake0)
920
921 (Load <t> ptr mem) && t.IsArray() && t.NumElem() == 1 && CanSSA(t) =>
922 (ArrayMake1 (Load <t.Elem()> ptr mem))
923
924 (Store _ (ArrayMake0) mem) => mem
925 (Store dst (ArrayMake1 e) mem) => (Store {e.Type} dst e mem)
926
927 // Putting [1]*byte and similar into direct interfaces.
928 (IMake _typ (ArrayMake1 val)) => (IMake _typ val)
929 (ArraySelect [0] (IData x)) => (IData x)
930
931 // string ops
932 // Decomposing StringMake and lowering of StringPtr and StringLen
933 // happens in a later pass, dec, so that these operations are available
934 // to other passes for optimizations.
935 (StringPtr (StringMake (Addr <t> {s} base) _)) => (Addr <t> {s} base)
936 (StringLen (StringMake _ (Const64 <t> [c]))) => (Const64 <t> [c])
937 (ConstString {str}) && config.PtrSize == 4 && str == "" =>
938 (StringMake (ConstNil) (Const32 <typ.Int> [0]))
939 (ConstString {str}) && config.PtrSize == 8 && str == "" =>
940 (StringMake (ConstNil) (Const64 <typ.Int> [0]))
941 (ConstString {str}) && config.PtrSize == 4 && str != "" =>
942 (StringMake
943 (Addr <typ.BytePtr> {fe.StringData(str)}
944 (SB))
945 (Const32 <typ.Int> [int32(len(str))]))
946 (ConstString {str}) && config.PtrSize == 8 && str != "" =>
947 (StringMake
948 (Addr <typ.BytePtr> {fe.StringData(str)}
949 (SB))
950 (Const64 <typ.Int> [int64(len(str))]))
951
952 // slice ops
953 // Only a few slice rules are provided here. See dec.rules for
954 // a more comprehensive set.
955 (SliceLen (SliceMake _ (Const64 <t> [c]) _)) => (Const64 <t> [c])
956 (SliceCap (SliceMake _ _ (Const64 <t> [c]))) => (Const64 <t> [c])
957 (SliceLen (SliceMake _ (Const32 <t> [c]) _)) => (Const32 <t> [c])
958 (SliceCap (SliceMake _ _ (Const32 <t> [c]))) => (Const32 <t> [c])
959 (SlicePtr (SliceMake (SlicePtr x) _ _)) => (SlicePtr x)
960 (SliceLen (SliceMake _ (SliceLen x) _)) => (SliceLen x)
961 (SliceCap (SliceMake _ _ (SliceCap x))) => (SliceCap x)
962 (SliceCap (SliceMake _ _ (SliceLen x))) => (SliceLen x)
963 (ConstSlice) && config.PtrSize == 4 =>
964 (SliceMake
965 (ConstNil <v.Type.Elem().PtrTo()>)
966 (Const32 <typ.Int> [0])
967 (Const32 <typ.Int> [0]))
968 (ConstSlice) && config.PtrSize == 8 =>
969 (SliceMake
970 (ConstNil <v.Type.Elem().PtrTo()>)
971 (Const64 <typ.Int> [0])
972 (Const64 <typ.Int> [0]))
973
974 // interface ops
975 (ConstInterface) =>
976 (IMake
977 (ConstNil <typ.Uintptr>)
978 (ConstNil <typ.BytePtr>))
979
980 (NilCheck ptr:(GetG mem) mem) => ptr
981
982 (If (Not cond) yes no) => (If cond no yes)
983 (If (ConstBool [c]) yes no) && c => (First yes no)
984 (If (ConstBool [c]) yes no) && !c => (First no yes)
985
986 (Phi <t> nx:(Not x) ny:(Not y)) && nx.Uses == 1 && ny.Uses == 1 => (Not (Phi <t> x y))
987
988 // Get rid of Convert ops for pointer arithmetic on unsafe.Pointer.
989 (Convert (Add(64|32) (Convert ptr mem) off) mem) => (AddPtr ptr off)
990 (Convert (Convert ptr mem) mem) => ptr
991 // Note: it is important that the target rewrite is ptr+(off1+off2), not (ptr+off1)+off2.
992 // We must ensure that no intermediate computations are invalid pointers.
993 (Convert a:(Add(64|32) (Add(64|32) (Convert ptr mem) off1) off2) mem) => (AddPtr ptr (Add(64|32) <a.Type> off1 off2))
994
995 // strength reduction of divide by a constant.
996 // See ../magic.go for a detailed description of these algorithms.
997
998 // Unsigned divide by power of 2. Strength reduce to a shift.
999 (Div8u n (Const8 [c])) && isPowerOfTwo(c) => (Rsh8Ux64 n (Const64 <typ.UInt64> [log8(c)]))
1000 (Div16u n (Const16 [c])) && isPowerOfTwo(c) => (Rsh16Ux64 n (Const64 <typ.UInt64> [log16(c)]))
1001 (Div32u n (Const32 [c])) && isPowerOfTwo(c) => (Rsh32Ux64 n (Const64 <typ.UInt64> [log32(c)]))
1002 (Div64u n (Const64 [c])) && isPowerOfTwo(c) => (Rsh64Ux64 n (Const64 <typ.UInt64> [log64(c)]))
1003 (Div64u n (Const64 [-1<<63])) => (Rsh64Ux64 n (Const64 <typ.UInt64> [63]))
1004
1005 // Signed non-negative divide by power of 2.
1006 (Div8 n (Const8 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh8Ux64 n (Const64 <typ.UInt64> [log8(c)]))
1007 (Div16 n (Const16 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh16Ux64 n (Const64 <typ.UInt64> [log16(c)]))
1008 (Div32 n (Const32 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh32Ux64 n (Const64 <typ.UInt64> [log32(c)]))
1009 (Div64 n (Const64 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (Rsh64Ux64 n (Const64 <typ.UInt64> [log64(c)]))
1010 (Div64 n (Const64 [-1<<63])) && isNonNegative(n) => (Const64 [0])
1011
1012 // Unsigned divide, not a power of 2. Strength reduce to a multiply.
1013 // For 8-bit divides, we just do a direct 9-bit by 8-bit multiply.
1014 (Div8u x (Const8 [c])) && umagicOK8(c) =>
1015 (Trunc32to8
1016 (Rsh32Ux64 <typ.UInt32>
1017 (Mul32 <typ.UInt32>
1018 (Const32 <typ.UInt32> [int32(1<<8+umagic8(c).m)])
1019 (ZeroExt8to32 x))
1020 (Const64 <typ.UInt64> [8+umagic8(c).s])))
1021
1022 // For 16-bit divides on 64-bit machines, we do a direct 17-bit by 16-bit multiply.
1023 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 8 =>
1024 (Trunc64to16
1025 (Rsh64Ux64 <typ.UInt64>
1026 (Mul64 <typ.UInt64>
1027 (Const64 <typ.UInt64> [int64(1<<16+umagic16(c).m)])
1028 (ZeroExt16to64 x))
1029 (Const64 <typ.UInt64> [16+umagic16(c).s])))
1030
1031 // For 16-bit divides on 32-bit machines
1032 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 4 && umagic16(c).m&1 == 0 =>
1033 (Trunc32to16
1034 (Rsh32Ux64 <typ.UInt32>
1035 (Mul32 <typ.UInt32>
1036 (Const32 <typ.UInt32> [int32(1<<15+umagic16(c).m/2)])
1037 (ZeroExt16to32 x))
1038 (Const64 <typ.UInt64> [16+umagic16(c).s-1])))
1039 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 4 && c&1 == 0 =>
1040 (Trunc32to16
1041 (Rsh32Ux64 <typ.UInt32>
1042 (Mul32 <typ.UInt32>
1043 (Const32 <typ.UInt32> [int32(1<<15+(umagic16(c).m+1)/2)])
1044 (Rsh32Ux64 <typ.UInt32> (ZeroExt16to32 x) (Const64 <typ.UInt64> [1])))
1045 (Const64 <typ.UInt64> [16+umagic16(c).s-2])))
1046 (Div16u x (Const16 [c])) && umagicOK16(c) && config.RegSize == 4 && config.useAvg =>
1047 (Trunc32to16
1048 (Rsh32Ux64 <typ.UInt32>
1049 (Avg32u
1050 (Lsh32x64 <typ.UInt32> (ZeroExt16to32 x) (Const64 <typ.UInt64> [16]))
1051 (Mul32 <typ.UInt32>
1052 (Const32 <typ.UInt32> [int32(umagic16(c).m)])
1053 (ZeroExt16to32 x)))
1054 (Const64 <typ.UInt64> [16+umagic16(c).s-1])))
1055
1056 // For 32-bit divides on 32-bit machines
1057 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 4 && umagic32(c).m&1 == 0 && config.useHmul =>
1058 (Rsh32Ux64 <typ.UInt32>
1059 (Hmul32u <typ.UInt32>
1060 (Const32 <typ.UInt32> [int32(1<<31+umagic32(c).m/2)])
1061 x)
1062 (Const64 <typ.UInt64> [umagic32(c).s-1]))
1063 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 4 && c&1 == 0 && config.useHmul =>
1064 (Rsh32Ux64 <typ.UInt32>
1065 (Hmul32u <typ.UInt32>
1066 (Const32 <typ.UInt32> [int32(1<<31+(umagic32(c).m+1)/2)])
1067 (Rsh32Ux64 <typ.UInt32> x (Const64 <typ.UInt64> [1])))
1068 (Const64 <typ.UInt64> [umagic32(c).s-2]))
1069 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 4 && config.useAvg && config.useHmul =>
1070 (Rsh32Ux64 <typ.UInt32>
1071 (Avg32u
1072 x
1073 (Hmul32u <typ.UInt32>
1074 (Const32 <typ.UInt32> [int32(umagic32(c).m)])
1075 x))
1076 (Const64 <typ.UInt64> [umagic32(c).s-1]))
1077
1078 // For 32-bit divides on 64-bit machines
1079 // We'll use a regular (non-hi) multiply for this case.
1080 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 8 && umagic32(c).m&1 == 0 =>
1081 (Trunc64to32
1082 (Rsh64Ux64 <typ.UInt64>
1083 (Mul64 <typ.UInt64>
1084 (Const64 <typ.UInt64> [int64(1<<31+umagic32(c).m/2)])
1085 (ZeroExt32to64 x))
1086 (Const64 <typ.UInt64> [32+umagic32(c).s-1])))
1087 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 8 && c&1 == 0 =>
1088 (Trunc64to32
1089 (Rsh64Ux64 <typ.UInt64>
1090 (Mul64 <typ.UInt64>
1091 (Const64 <typ.UInt64> [int64(1<<31+(umagic32(c).m+1)/2)])
1092 (Rsh64Ux64 <typ.UInt64> (ZeroExt32to64 x) (Const64 <typ.UInt64> [1])))
1093 (Const64 <typ.UInt64> [32+umagic32(c).s-2])))
1094 (Div32u x (Const32 [c])) && umagicOK32(c) && config.RegSize == 8 && config.useAvg =>
1095 (Trunc64to32
1096 (Rsh64Ux64 <typ.UInt64>
1097 (Avg64u
1098 (Lsh64x64 <typ.UInt64> (ZeroExt32to64 x) (Const64 <typ.UInt64> [32]))
1099 (Mul64 <typ.UInt64>
1100 (Const64 <typ.UInt32> [int64(umagic32(c).m)])
1101 (ZeroExt32to64 x)))
1102 (Const64 <typ.UInt64> [32+umagic32(c).s-1])))
1103
1104 // For unsigned 64-bit divides on 32-bit machines,
1105 // if the constant fits in 16 bits (so that the last term
1106 // fits in 32 bits), convert to three 32-bit divides by a constant.
1107 //
1108 // If 1<<32 = Q * c + R
1109 // and x = hi << 32 + lo
1110 //
1111 // Then x = (hi/c*c + hi%c) << 32 + lo
1112 // = hi/c*c<<32 + hi%c<<32 + lo
1113 // = hi/c*c<<32 + (hi%c)*(Q*c+R) + lo/c*c + lo%c
1114 // = hi/c*c<<32 + (hi%c)*Q*c + lo/c*c + (hi%c*R+lo%c)
1115 // and x / c = (hi/c)<<32 + (hi%c)*Q + lo/c + (hi%c*R+lo%c)/c
1116 (Div64u x (Const64 [c])) && c > 0 && c <= 0xFFFF && umagicOK32(int32(c)) && config.RegSize == 4 && config.useHmul =>
1117 (Add64
1118 (Add64 <typ.UInt64>
1119 (Add64 <typ.UInt64>
1120 (Lsh64x64 <typ.UInt64>
1121 (ZeroExt32to64
1122 (Div32u <typ.UInt32>
1123 (Trunc64to32 <typ.UInt32> (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [32])))
1124 (Const32 <typ.UInt32> [int32(c)])))
1125 (Const64 <typ.UInt64> [32]))
1126 (ZeroExt32to64 (Div32u <typ.UInt32> (Trunc64to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(c)]))))
1127 (Mul64 <typ.UInt64>
1128 (ZeroExt32to64 <typ.UInt64>
1129 (Mod32u <typ.UInt32>
1130 (Trunc64to32 <typ.UInt32> (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [32])))
1131 (Const32 <typ.UInt32> [int32(c)])))
1132 (Const64 <typ.UInt64> [int64((1<<32)/c)])))
1133 (ZeroExt32to64
1134 (Div32u <typ.UInt32>
1135 (Add32 <typ.UInt32>
1136 (Mod32u <typ.UInt32> (Trunc64to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(c)]))
1137 (Mul32 <typ.UInt32>
1138 (Mod32u <typ.UInt32>
1139 (Trunc64to32 <typ.UInt32> (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [32])))
1140 (Const32 <typ.UInt32> [int32(c)]))
1141 (Const32 <typ.UInt32> [int32((1<<32)%c)])))
1142 (Const32 <typ.UInt32> [int32(c)]))))
1143
1144 // For 64-bit divides on 64-bit machines
1145 // (64-bit divides on 32-bit machines are lowered to a runtime call by the walk pass.)
1146 (Div64u x (Const64 [c])) && umagicOK64(c) && config.RegSize == 8 && umagic64(c).m&1 == 0 && config.useHmul =>
1147 (Rsh64Ux64 <typ.UInt64>
1148 (Hmul64u <typ.UInt64>
1149 (Const64 <typ.UInt64> [int64(1<<63+umagic64(c).m/2)])
1150 x)
1151 (Const64 <typ.UInt64> [umagic64(c).s-1]))
1152 (Div64u x (Const64 [c])) && umagicOK64(c) && config.RegSize == 8 && c&1 == 0 && config.useHmul =>
1153 (Rsh64Ux64 <typ.UInt64>
1154 (Hmul64u <typ.UInt64>
1155 (Const64 <typ.UInt64> [int64(1<<63+(umagic64(c).m+1)/2)])
1156 (Rsh64Ux64 <typ.UInt64> x (Const64 <typ.UInt64> [1])))
1157 (Const64 <typ.UInt64> [umagic64(c).s-2]))
1158 (Div64u x (Const64 [c])) && umagicOK64(c) && config.RegSize == 8 && config.useAvg && config.useHmul =>
1159 (Rsh64Ux64 <typ.UInt64>
1160 (Avg64u
1161 x
1162 (Hmul64u <typ.UInt64>
1163 (Const64 <typ.UInt64> [int64(umagic64(c).m)])
1164 x))
1165 (Const64 <typ.UInt64> [umagic64(c).s-1]))
1166
1167 // Signed divide by a negative constant. Rewrite to divide by a positive constant.
1168 (Div8 <t> n (Const8 [c])) && c < 0 && c != -1<<7 => (Neg8 (Div8 <t> n (Const8 <t> [-c])))
1169 (Div16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 => (Neg16 (Div16 <t> n (Const16 <t> [-c])))
1170 (Div32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 => (Neg32 (Div32 <t> n (Const32 <t> [-c])))
1171 (Div64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 => (Neg64 (Div64 <t> n (Const64 <t> [-c])))
1172
1173 // Dividing by the most-negative number. Result is always 0 except
1174 // if the input is also the most-negative number.
1175 // We can detect that using the sign bit of x & -x.
1176 (Div8 <t> x (Const8 [-1<<7 ])) => (Rsh8Ux64 (And8 <t> x (Neg8 <t> x)) (Const64 <typ.UInt64> [7 ]))
1177 (Div16 <t> x (Const16 [-1<<15])) => (Rsh16Ux64 (And16 <t> x (Neg16 <t> x)) (Const64 <typ.UInt64> [15]))
1178 (Div32 <t> x (Const32 [-1<<31])) => (Rsh32Ux64 (And32 <t> x (Neg32 <t> x)) (Const64 <typ.UInt64> [31]))
1179 (Div64 <t> x (Const64 [-1<<63])) => (Rsh64Ux64 (And64 <t> x (Neg64 <t> x)) (Const64 <typ.UInt64> [63]))
1180
1181 // Signed divide by power of 2.
1182 // n / c = n >> log(c) if n >= 0
1183 // = (n+c-1) >> log(c) if n < 0
1184 // We conditionally add c-1 by adding n>>63>>(64-log(c)) (first shift signed, second shift unsigned).
1185 (Div8 <t> n (Const8 [c])) && isPowerOfTwo(c) =>
1186 (Rsh8x64
1187 (Add8 <t> n (Rsh8Ux64 <t> (Rsh8x64 <t> n (Const64 <typ.UInt64> [ 7])) (Const64 <typ.UInt64> [int64( 8-log8(c))])))
1188 (Const64 <typ.UInt64> [int64(log8(c))]))
1189 (Div16 <t> n (Const16 [c])) && isPowerOfTwo(c) =>
1190 (Rsh16x64
1191 (Add16 <t> n (Rsh16Ux64 <t> (Rsh16x64 <t> n (Const64 <typ.UInt64> [15])) (Const64 <typ.UInt64> [int64(16-log16(c))])))
1192 (Const64 <typ.UInt64> [int64(log16(c))]))
1193 (Div32 <t> n (Const32 [c])) && isPowerOfTwo(c) =>
1194 (Rsh32x64
1195 (Add32 <t> n (Rsh32Ux64 <t> (Rsh32x64 <t> n (Const64 <typ.UInt64> [31])) (Const64 <typ.UInt64> [int64(32-log32(c))])))
1196 (Const64 <typ.UInt64> [int64(log32(c))]))
1197 (Div64 <t> n (Const64 [c])) && isPowerOfTwo(c) =>
1198 (Rsh64x64
1199 (Add64 <t> n (Rsh64Ux64 <t> (Rsh64x64 <t> n (Const64 <typ.UInt64> [63])) (Const64 <typ.UInt64> [int64(64-log64(c))])))
1200 (Const64 <typ.UInt64> [int64(log64(c))]))
1201
1202 // Signed divide, not a power of 2. Strength reduce to a multiply.
1203 (Div8 <t> x (Const8 [c])) && smagicOK8(c) =>
1204 (Sub8 <t>
1205 (Rsh32x64 <t>
1206 (Mul32 <typ.UInt32>
1207 (Const32 <typ.UInt32> [int32(smagic8(c).m)])
1208 (SignExt8to32 x))
1209 (Const64 <typ.UInt64> [8+smagic8(c).s]))
1210 (Rsh32x64 <t>
1211 (SignExt8to32 x)
1212 (Const64 <typ.UInt64> [31])))
1213 (Div16 <t> x (Const16 [c])) && smagicOK16(c) =>
1214 (Sub16 <t>
1215 (Rsh32x64 <t>
1216 (Mul32 <typ.UInt32>
1217 (Const32 <typ.UInt32> [int32(smagic16(c).m)])
1218 (SignExt16to32 x))
1219 (Const64 <typ.UInt64> [16+smagic16(c).s]))
1220 (Rsh32x64 <t>
1221 (SignExt16to32 x)
1222 (Const64 <typ.UInt64> [31])))
1223 (Div32 <t> x (Const32 [c])) && smagicOK32(c) && config.RegSize == 8 =>
1224 (Sub32 <t>
1225 (Rsh64x64 <t>
1226 (Mul64 <typ.UInt64>
1227 (Const64 <typ.UInt64> [int64(smagic32(c).m)])
1228 (SignExt32to64 x))
1229 (Const64 <typ.UInt64> [32+smagic32(c).s]))
1230 (Rsh64x64 <t>
1231 (SignExt32to64 x)
1232 (Const64 <typ.UInt64> [63])))
1233 (Div32 <t> x (Const32 [c])) && smagicOK32(c) && config.RegSize == 4 && smagic32(c).m&1 == 0 && config.useHmul =>
1234 (Sub32 <t>
1235 (Rsh32x64 <t>
1236 (Hmul32 <t>
1237 (Const32 <typ.UInt32> [int32(smagic32(c).m/2)])
1238 x)
1239 (Const64 <typ.UInt64> [smagic32(c).s-1]))
1240 (Rsh32x64 <t>
1241 x
1242 (Const64 <typ.UInt64> [31])))
1243 (Div32 <t> x (Const32 [c])) && smagicOK32(c) && config.RegSize == 4 && smagic32(c).m&1 != 0 && config.useHmul =>
1244 (Sub32 <t>
1245 (Rsh32x64 <t>
1246 (Add32 <t>
1247 (Hmul32 <t>
1248 (Const32 <typ.UInt32> [int32(smagic32(c).m)])
1249 x)
1250 x)
1251 (Const64 <typ.UInt64> [smagic32(c).s]))
1252 (Rsh32x64 <t>
1253 x
1254 (Const64 <typ.UInt64> [31])))
1255 (Div64 <t> x (Const64 [c])) && smagicOK64(c) && smagic64(c).m&1 == 0 && config.useHmul =>
1256 (Sub64 <t>
1257 (Rsh64x64 <t>
1258 (Hmul64 <t>
1259 (Const64 <typ.UInt64> [int64(smagic64(c).m/2)])
1260 x)
1261 (Const64 <typ.UInt64> [smagic64(c).s-1]))
1262 (Rsh64x64 <t>
1263 x
1264 (Const64 <typ.UInt64> [63])))
1265 (Div64 <t> x (Const64 [c])) && smagicOK64(c) && smagic64(c).m&1 != 0 && config.useHmul =>
1266 (Sub64 <t>
1267 (Rsh64x64 <t>
1268 (Add64 <t>
1269 (Hmul64 <t>
1270 (Const64 <typ.UInt64> [int64(smagic64(c).m)])
1271 x)
1272 x)
1273 (Const64 <typ.UInt64> [smagic64(c).s]))
1274 (Rsh64x64 <t>
1275 x
1276 (Const64 <typ.UInt64> [63])))
1277
1278 // Unsigned mod by power of 2 constant.
1279 (Mod8u <t> n (Const8 [c])) && isPowerOfTwo(c) => (And8 n (Const8 <t> [c-1]))
1280 (Mod16u <t> n (Const16 [c])) && isPowerOfTwo(c) => (And16 n (Const16 <t> [c-1]))
1281 (Mod32u <t> n (Const32 [c])) && isPowerOfTwo(c) => (And32 n (Const32 <t> [c-1]))
1282 (Mod64u <t> n (Const64 [c])) && isPowerOfTwo(c) => (And64 n (Const64 <t> [c-1]))
1283 (Mod64u <t> n (Const64 [-1<<63])) => (And64 n (Const64 <t> [1<<63-1]))
1284
1285 // Signed non-negative mod by power of 2 constant.
1286 (Mod8 <t> n (Const8 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And8 n (Const8 <t> [c-1]))
1287 (Mod16 <t> n (Const16 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And16 n (Const16 <t> [c-1]))
1288 (Mod32 <t> n (Const32 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And32 n (Const32 <t> [c-1]))
1289 (Mod64 <t> n (Const64 [c])) && isNonNegative(n) && isPowerOfTwo(c) => (And64 n (Const64 <t> [c-1]))
1290 (Mod64 n (Const64 [-1<<63])) && isNonNegative(n) => n
1291
1292 // Signed mod by negative constant.
1293 (Mod8 <t> n (Const8 [c])) && c < 0 && c != -1<<7 => (Mod8 <t> n (Const8 <t> [-c]))
1294 (Mod16 <t> n (Const16 [c])) && c < 0 && c != -1<<15 => (Mod16 <t> n (Const16 <t> [-c]))
1295 (Mod32 <t> n (Const32 [c])) && c < 0 && c != -1<<31 => (Mod32 <t> n (Const32 <t> [-c]))
1296 (Mod64 <t> n (Const64 [c])) && c < 0 && c != -1<<63 => (Mod64 <t> n (Const64 <t> [-c]))
1297
1298 // All other mods by constants, do A%B = A-(A/B*B).
1299 // This implements % with two * and a bunch of ancillary ops.
1300 // One of the * is free if the user's code also computes A/B.
1301 (Mod8 <t> x (Const8 [c])) && x.Op != OpConst8 && (c > 0 || c == -1<<7)
1302 => (Sub8 x (Mul8 <t> (Div8 <t> x (Const8 <t> [c])) (Const8 <t> [c])))
1303 (Mod16 <t> x (Const16 [c])) && x.Op != OpConst16 && (c > 0 || c == -1<<15)
1304 => (Sub16 x (Mul16 <t> (Div16 <t> x (Const16 <t> [c])) (Const16 <t> [c])))
1305 (Mod32 <t> x (Const32 [c])) && x.Op != OpConst32 && (c > 0 || c == -1<<31)
1306 => (Sub32 x (Mul32 <t> (Div32 <t> x (Const32 <t> [c])) (Const32 <t> [c])))
1307 (Mod64 <t> x (Const64 [c])) && x.Op != OpConst64 && (c > 0 || c == -1<<63)
1308 => (Sub64 x (Mul64 <t> (Div64 <t> x (Const64 <t> [c])) (Const64 <t> [c])))
1309 (Mod8u <t> x (Const8 [c])) && x.Op != OpConst8 && c > 0 && umagicOK8( c)
1310 => (Sub8 x (Mul8 <t> (Div8u <t> x (Const8 <t> [c])) (Const8 <t> [c])))
1311 (Mod16u <t> x (Const16 [c])) && x.Op != OpConst16 && c > 0 && umagicOK16(c)
1312 => (Sub16 x (Mul16 <t> (Div16u <t> x (Const16 <t> [c])) (Const16 <t> [c])))
1313 (Mod32u <t> x (Const32 [c])) && x.Op != OpConst32 && c > 0 && umagicOK32(c)
1314 => (Sub32 x (Mul32 <t> (Div32u <t> x (Const32 <t> [c])) (Const32 <t> [c])))
1315 (Mod64u <t> x (Const64 [c])) && x.Op != OpConst64 && c > 0 && umagicOK64(c)
1316 => (Sub64 x (Mul64 <t> (Div64u <t> x (Const64 <t> [c])) (Const64 <t> [c])))
1317
1318 // For architectures without rotates on less than 32-bits, promote these checks to 32-bit.
1319 (Eq8 (Mod8u x (Const8 [c])) (Const8 [0])) && x.Op != OpConst8 && udivisibleOK8(c) && !hasSmallRotate(config) =>
1320 (Eq32 (Mod32u <typ.UInt32> (ZeroExt8to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(uint8(c))])) (Const32 <typ.UInt32> [0]))
1321 (Eq16 (Mod16u x (Const16 [c])) (Const16 [0])) && x.Op != OpConst16 && udivisibleOK16(c) && !hasSmallRotate(config) =>
1322 (Eq32 (Mod32u <typ.UInt32> (ZeroExt16to32 <typ.UInt32> x) (Const32 <typ.UInt32> [int32(uint16(c))])) (Const32 <typ.UInt32> [0]))
1323 (Eq8 (Mod8 x (Const8 [c])) (Const8 [0])) && x.Op != OpConst8 && sdivisibleOK8(c) && !hasSmallRotate(config) =>
1324 (Eq32 (Mod32 <typ.Int32> (SignExt8to32 <typ.Int32> x) (Const32 <typ.Int32> [int32(c)])) (Const32 <typ.Int32> [0]))
1325 (Eq16 (Mod16 x (Const16 [c])) (Const16 [0])) && x.Op != OpConst16 && sdivisibleOK16(c) && !hasSmallRotate(config) =>
1326 (Eq32 (Mod32 <typ.Int32> (SignExt16to32 <typ.Int32> x) (Const32 <typ.Int32> [int32(c)])) (Const32 <typ.Int32> [0]))
1327
1328 // Divisibility checks x%c == 0 convert to multiply and rotate.
1329 // Note, x%c == 0 is rewritten as x == c*(x/c) during the opt pass
1330 // where (x/c) is performed using multiplication with magic constants.
1331 // To rewrite x%c == 0 requires pattern matching the rewritten expression
1332 // and checking that the division by the same constant wasn't already calculated.
1333 // This check is made by counting uses of the magic constant multiplication.
1334 // Note that if there were an intermediate opt pass, this rule could be applied
1335 // directly on the Div op and magic division rewrites could be delayed to late opt.
1336
1337 // Unsigned divisibility checks convert to multiply and rotate.
1338 (Eq8 x (Mul8 (Const8 [c])
1339 (Trunc32to8
1340 (Rsh32Ux64
1341 mul:(Mul32
1342 (Const32 [m])
1343 (ZeroExt8to32 x))
1344 (Const64 [s])))
1345 )
1346 )
1347 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1348 && m == int32(1<<8+umagic8(c).m) && s == 8+umagic8(c).s
1349 && x.Op != OpConst8 && udivisibleOK8(c)
1350 => (Leq8U
1351 (RotateLeft8 <typ.UInt8>
1352 (Mul8 <typ.UInt8>
1353 (Const8 <typ.UInt8> [int8(udivisible8(c).m)])
1354 x)
1355 (Const8 <typ.UInt8> [int8(8-udivisible8(c).k)])
1356 )
1357 (Const8 <typ.UInt8> [int8(udivisible8(c).max)])
1358 )
1359
1360 (Eq16 x (Mul16 (Const16 [c])
1361 (Trunc64to16
1362 (Rsh64Ux64
1363 mul:(Mul64
1364 (Const64 [m])
1365 (ZeroExt16to64 x))
1366 (Const64 [s])))
1367 )
1368 )
1369 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1370 && m == int64(1<<16+umagic16(c).m) && s == 16+umagic16(c).s
1371 && x.Op != OpConst16 && udivisibleOK16(c)
1372 => (Leq16U
1373 (RotateLeft16 <typ.UInt16>
1374 (Mul16 <typ.UInt16>
1375 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1376 x)
1377 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1378 )
1379 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1380 )
1381
1382 (Eq16 x (Mul16 (Const16 [c])
1383 (Trunc32to16
1384 (Rsh32Ux64
1385 mul:(Mul32
1386 (Const32 [m])
1387 (ZeroExt16to32 x))
1388 (Const64 [s])))
1389 )
1390 )
1391 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1392 && m == int32(1<<15+umagic16(c).m/2) && s == 16+umagic16(c).s-1
1393 && x.Op != OpConst16 && udivisibleOK16(c)
1394 => (Leq16U
1395 (RotateLeft16 <typ.UInt16>
1396 (Mul16 <typ.UInt16>
1397 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1398 x)
1399 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1400 )
1401 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1402 )
1403
1404 (Eq16 x (Mul16 (Const16 [c])
1405 (Trunc32to16
1406 (Rsh32Ux64
1407 mul:(Mul32
1408 (Const32 [m])
1409 (Rsh32Ux64 (ZeroExt16to32 x) (Const64 [1])))
1410 (Const64 [s])))
1411 )
1412 )
1413 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1414 && m == int32(1<<15+(umagic16(c).m+1)/2) && s == 16+umagic16(c).s-2
1415 && x.Op != OpConst16 && udivisibleOK16(c)
1416 => (Leq16U
1417 (RotateLeft16 <typ.UInt16>
1418 (Mul16 <typ.UInt16>
1419 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1420 x)
1421 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1422 )
1423 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1424 )
1425
1426 (Eq16 x (Mul16 (Const16 [c])
1427 (Trunc32to16
1428 (Rsh32Ux64
1429 (Avg32u
1430 (Lsh32x64 (ZeroExt16to32 x) (Const64 [16]))
1431 mul:(Mul32
1432 (Const32 [m])
1433 (ZeroExt16to32 x)))
1434 (Const64 [s])))
1435 )
1436 )
1437 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1438 && m == int32(umagic16(c).m) && s == 16+umagic16(c).s-1
1439 && x.Op != OpConst16 && udivisibleOK16(c)
1440 => (Leq16U
1441 (RotateLeft16 <typ.UInt16>
1442 (Mul16 <typ.UInt16>
1443 (Const16 <typ.UInt16> [int16(udivisible16(c).m)])
1444 x)
1445 (Const16 <typ.UInt16> [int16(16-udivisible16(c).k)])
1446 )
1447 (Const16 <typ.UInt16> [int16(udivisible16(c).max)])
1448 )
1449
1450 (Eq32 x (Mul32 (Const32 [c])
1451 (Rsh32Ux64
1452 mul:(Hmul32u
1453 (Const32 [m])
1454 x)
1455 (Const64 [s]))
1456 )
1457 )
1458 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1459 && m == int32(1<<31+umagic32(c).m/2) && s == umagic32(c).s-1
1460 && x.Op != OpConst32 && udivisibleOK32(c)
1461 => (Leq32U
1462 (RotateLeft32 <typ.UInt32>
1463 (Mul32 <typ.UInt32>
1464 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1465 x)
1466 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1467 )
1468 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1469 )
1470
1471 (Eq32 x (Mul32 (Const32 [c])
1472 (Rsh32Ux64
1473 mul:(Hmul32u
1474 (Const32 <typ.UInt32> [m])
1475 (Rsh32Ux64 x (Const64 [1])))
1476 (Const64 [s]))
1477 )
1478 )
1479 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1480 && m == int32(1<<31+(umagic32(c).m+1)/2) && s == umagic32(c).s-2
1481 && x.Op != OpConst32 && udivisibleOK32(c)
1482 => (Leq32U
1483 (RotateLeft32 <typ.UInt32>
1484 (Mul32 <typ.UInt32>
1485 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1486 x)
1487 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1488 )
1489 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1490 )
1491
1492 (Eq32 x (Mul32 (Const32 [c])
1493 (Rsh32Ux64
1494 (Avg32u
1495 x
1496 mul:(Hmul32u
1497 (Const32 [m])
1498 x))
1499 (Const64 [s]))
1500 )
1501 )
1502 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1503 && m == int32(umagic32(c).m) && s == umagic32(c).s-1
1504 && x.Op != OpConst32 && udivisibleOK32(c)
1505 => (Leq32U
1506 (RotateLeft32 <typ.UInt32>
1507 (Mul32 <typ.UInt32>
1508 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1509 x)
1510 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1511 )
1512 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1513 )
1514
1515 (Eq32 x (Mul32 (Const32 [c])
1516 (Trunc64to32
1517 (Rsh64Ux64
1518 mul:(Mul64
1519 (Const64 [m])
1520 (ZeroExt32to64 x))
1521 (Const64 [s])))
1522 )
1523 )
1524 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1525 && m == int64(1<<31+umagic32(c).m/2) && s == 32+umagic32(c).s-1
1526 && x.Op != OpConst32 && udivisibleOK32(c)
1527 => (Leq32U
1528 (RotateLeft32 <typ.UInt32>
1529 (Mul32 <typ.UInt32>
1530 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1531 x)
1532 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1533 )
1534 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1535 )
1536
1537 (Eq32 x (Mul32 (Const32 [c])
1538 (Trunc64to32
1539 (Rsh64Ux64
1540 mul:(Mul64
1541 (Const64 [m])
1542 (Rsh64Ux64 (ZeroExt32to64 x) (Const64 [1])))
1543 (Const64 [s])))
1544 )
1545 )
1546 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1547 && m == int64(1<<31+(umagic32(c).m+1)/2) && s == 32+umagic32(c).s-2
1548 && x.Op != OpConst32 && udivisibleOK32(c)
1549 => (Leq32U
1550 (RotateLeft32 <typ.UInt32>
1551 (Mul32 <typ.UInt32>
1552 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1553 x)
1554 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1555 )
1556 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1557 )
1558
1559 (Eq32 x (Mul32 (Const32 [c])
1560 (Trunc64to32
1561 (Rsh64Ux64
1562 (Avg64u
1563 (Lsh64x64 (ZeroExt32to64 x) (Const64 [32]))
1564 mul:(Mul64
1565 (Const64 [m])
1566 (ZeroExt32to64 x)))
1567 (Const64 [s])))
1568 )
1569 )
1570 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1571 && m == int64(umagic32(c).m) && s == 32+umagic32(c).s-1
1572 && x.Op != OpConst32 && udivisibleOK32(c)
1573 => (Leq32U
1574 (RotateLeft32 <typ.UInt32>
1575 (Mul32 <typ.UInt32>
1576 (Const32 <typ.UInt32> [int32(udivisible32(c).m)])
1577 x)
1578 (Const32 <typ.UInt32> [int32(32-udivisible32(c).k)])
1579 )
1580 (Const32 <typ.UInt32> [int32(udivisible32(c).max)])
1581 )
1582
1583 (Eq64 x (Mul64 (Const64 [c])
1584 (Rsh64Ux64
1585 mul:(Hmul64u
1586 (Const64 [m])
1587 x)
1588 (Const64 [s]))
1589 )
1590 ) && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1591 && m == int64(1<<63+umagic64(c).m/2) && s == umagic64(c).s-1
1592 && x.Op != OpConst64 && udivisibleOK64(c)
1593 => (Leq64U
1594 (RotateLeft64 <typ.UInt64>
1595 (Mul64 <typ.UInt64>
1596 (Const64 <typ.UInt64> [int64(udivisible64(c).m)])
1597 x)
1598 (Const64 <typ.UInt64> [64-udivisible64(c).k])
1599 )
1600 (Const64 <typ.UInt64> [int64(udivisible64(c).max)])
1601 )
1602 (Eq64 x (Mul64 (Const64 [c])
1603 (Rsh64Ux64
1604 mul:(Hmul64u
1605 (Const64 [m])
1606 (Rsh64Ux64 x (Const64 [1])))
1607 (Const64 [s]))
1608 )
1609 ) && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1610 && m == int64(1<<63+(umagic64(c).m+1)/2) && s == umagic64(c).s-2
1611 && x.Op != OpConst64 && udivisibleOK64(c)
1612 => (Leq64U
1613 (RotateLeft64 <typ.UInt64>
1614 (Mul64 <typ.UInt64>
1615 (Const64 <typ.UInt64> [int64(udivisible64(c).m)])
1616 x)
1617 (Const64 <typ.UInt64> [64-udivisible64(c).k])
1618 )
1619 (Const64 <typ.UInt64> [int64(udivisible64(c).max)])
1620 )
1621 (Eq64 x (Mul64 (Const64 [c])
1622 (Rsh64Ux64
1623 (Avg64u
1624 x
1625 mul:(Hmul64u
1626 (Const64 [m])
1627 x))
1628 (Const64 [s]))
1629 )
1630 ) && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1631 && m == int64(umagic64(c).m) && s == umagic64(c).s-1
1632 && x.Op != OpConst64 && udivisibleOK64(c)
1633 => (Leq64U
1634 (RotateLeft64 <typ.UInt64>
1635 (Mul64 <typ.UInt64>
1636 (Const64 <typ.UInt64> [int64(udivisible64(c).m)])
1637 x)
1638 (Const64 <typ.UInt64> [64-udivisible64(c).k])
1639 )
1640 (Const64 <typ.UInt64> [int64(udivisible64(c).max)])
1641 )
1642
1643 // Signed divisibility checks convert to multiply, add and rotate.
1644 (Eq8 x (Mul8 (Const8 [c])
1645 (Sub8
1646 (Rsh32x64
1647 mul:(Mul32
1648 (Const32 [m])
1649 (SignExt8to32 x))
1650 (Const64 [s]))
1651 (Rsh32x64
1652 (SignExt8to32 x)
1653 (Const64 [31])))
1654 )
1655 )
1656 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1657 && m == int32(smagic8(c).m) && s == 8+smagic8(c).s
1658 && x.Op != OpConst8 && sdivisibleOK8(c)
1659 => (Leq8U
1660 (RotateLeft8 <typ.UInt8>
1661 (Add8 <typ.UInt8>
1662 (Mul8 <typ.UInt8>
1663 (Const8 <typ.UInt8> [int8(sdivisible8(c).m)])
1664 x)
1665 (Const8 <typ.UInt8> [int8(sdivisible8(c).a)])
1666 )
1667 (Const8 <typ.UInt8> [int8(8-sdivisible8(c).k)])
1668 )
1669 (Const8 <typ.UInt8> [int8(sdivisible8(c).max)])
1670 )
1671
1672 (Eq16 x (Mul16 (Const16 [c])
1673 (Sub16
1674 (Rsh32x64
1675 mul:(Mul32
1676 (Const32 [m])
1677 (SignExt16to32 x))
1678 (Const64 [s]))
1679 (Rsh32x64
1680 (SignExt16to32 x)
1681 (Const64 [31])))
1682 )
1683 )
1684 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1685 && m == int32(smagic16(c).m) && s == 16+smagic16(c).s
1686 && x.Op != OpConst16 && sdivisibleOK16(c)
1687 => (Leq16U
1688 (RotateLeft16 <typ.UInt16>
1689 (Add16 <typ.UInt16>
1690 (Mul16 <typ.UInt16>
1691 (Const16 <typ.UInt16> [int16(sdivisible16(c).m)])
1692 x)
1693 (Const16 <typ.UInt16> [int16(sdivisible16(c).a)])
1694 )
1695 (Const16 <typ.UInt16> [int16(16-sdivisible16(c).k)])
1696 )
1697 (Const16 <typ.UInt16> [int16(sdivisible16(c).max)])
1698 )
1699
1700 (Eq32 x (Mul32 (Const32 [c])
1701 (Sub32
1702 (Rsh64x64
1703 mul:(Mul64
1704 (Const64 [m])
1705 (SignExt32to64 x))
1706 (Const64 [s]))
1707 (Rsh64x64
1708 (SignExt32to64 x)
1709 (Const64 [63])))
1710 )
1711 )
1712 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1713 && m == int64(smagic32(c).m) && s == 32+smagic32(c).s
1714 && x.Op != OpConst32 && sdivisibleOK32(c)
1715 => (Leq32U
1716 (RotateLeft32 <typ.UInt32>
1717 (Add32 <typ.UInt32>
1718 (Mul32 <typ.UInt32>
1719 (Const32 <typ.UInt32> [int32(sdivisible32(c).m)])
1720 x)
1721 (Const32 <typ.UInt32> [int32(sdivisible32(c).a)])
1722 )
1723 (Const32 <typ.UInt32> [int32(32-sdivisible32(c).k)])
1724 )
1725 (Const32 <typ.UInt32> [int32(sdivisible32(c).max)])
1726 )
1727
1728 (Eq32 x (Mul32 (Const32 [c])
1729 (Sub32
1730 (Rsh32x64
1731 mul:(Hmul32
1732 (Const32 [m])
1733 x)
1734 (Const64 [s]))
1735 (Rsh32x64
1736 x
1737 (Const64 [31])))
1738 )
1739 )
1740 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1741 && m == int32(smagic32(c).m/2) && s == smagic32(c).s-1
1742 && x.Op != OpConst32 && sdivisibleOK32(c)
1743 => (Leq32U
1744 (RotateLeft32 <typ.UInt32>
1745 (Add32 <typ.UInt32>
1746 (Mul32 <typ.UInt32>
1747 (Const32 <typ.UInt32> [int32(sdivisible32(c).m)])
1748 x)
1749 (Const32 <typ.UInt32> [int32(sdivisible32(c).a)])
1750 )
1751 (Const32 <typ.UInt32> [int32(32-sdivisible32(c).k)])
1752 )
1753 (Const32 <typ.UInt32> [int32(sdivisible32(c).max)])
1754 )
1755
1756 (Eq32 x (Mul32 (Const32 [c])
1757 (Sub32
1758 (Rsh32x64
1759 (Add32
1760 mul:(Hmul32
1761 (Const32 [m])
1762 x)
1763 x)
1764 (Const64 [s]))
1765 (Rsh32x64
1766 x
1767 (Const64 [31])))
1768 )
1769 )
1770 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1771 && m == int32(smagic32(c).m) && s == smagic32(c).s
1772 && x.Op != OpConst32 && sdivisibleOK32(c)
1773 => (Leq32U
1774 (RotateLeft32 <typ.UInt32>
1775 (Add32 <typ.UInt32>
1776 (Mul32 <typ.UInt32>
1777 (Const32 <typ.UInt32> [int32(sdivisible32(c).m)])
1778 x)
1779 (Const32 <typ.UInt32> [int32(sdivisible32(c).a)])
1780 )
1781 (Const32 <typ.UInt32> [int32(32-sdivisible32(c).k)])
1782 )
1783 (Const32 <typ.UInt32> [int32(sdivisible32(c).max)])
1784 )
1785
1786 (Eq64 x (Mul64 (Const64 [c])
1787 (Sub64
1788 (Rsh64x64
1789 mul:(Hmul64
1790 (Const64 [m])
1791 x)
1792 (Const64 [s]))
1793 (Rsh64x64
1794 x
1795 (Const64 [63])))
1796 )
1797 )
1798 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1799 && m == int64(smagic64(c).m/2) && s == smagic64(c).s-1
1800 && x.Op != OpConst64 && sdivisibleOK64(c)
1801 => (Leq64U
1802 (RotateLeft64 <typ.UInt64>
1803 (Add64 <typ.UInt64>
1804 (Mul64 <typ.UInt64>
1805 (Const64 <typ.UInt64> [int64(sdivisible64(c).m)])
1806 x)
1807 (Const64 <typ.UInt64> [int64(sdivisible64(c).a)])
1808 )
1809 (Const64 <typ.UInt64> [64-sdivisible64(c).k])
1810 )
1811 (Const64 <typ.UInt64> [int64(sdivisible64(c).max)])
1812 )
1813
1814 (Eq64 x (Mul64 (Const64 [c])
1815 (Sub64
1816 (Rsh64x64
1817 (Add64
1818 mul:(Hmul64
1819 (Const64 [m])
1820 x)
1821 x)
1822 (Const64 [s]))
1823 (Rsh64x64
1824 x
1825 (Const64 [63])))
1826 )
1827 )
1828 && v.Block.Func.pass.name != "opt" && mul.Uses == 1
1829 && m == int64(smagic64(c).m) && s == smagic64(c).s
1830 && x.Op != OpConst64 && sdivisibleOK64(c)
1831 => (Leq64U
1832 (RotateLeft64 <typ.UInt64>
1833 (Add64 <typ.UInt64>
1834 (Mul64 <typ.UInt64>
1835 (Const64 <typ.UInt64> [int64(sdivisible64(c).m)])
1836 x)
1837 (Const64 <typ.UInt64> [int64(sdivisible64(c).a)])
1838 )
1839 (Const64 <typ.UInt64> [64-sdivisible64(c).k])
1840 )
1841 (Const64 <typ.UInt64> [int64(sdivisible64(c).max)])
1842 )
1843
1844 // Divisibility check for signed integers for power of two constant are simple mask.
1845 // However, we must match against the rewritten n%c == 0 -> n - c*(n/c) == 0 -> n == c*(n/c)
1846 // where n/c contains fixup code to handle signed n.
1847 ((Eq8|Neq8) n (Lsh8x64
1848 (Rsh8x64
1849 (Add8 <t> n (Rsh8Ux64 <t> (Rsh8x64 <t> n (Const64 <typ.UInt64> [ 7])) (Const64 <typ.UInt64> [kbar])))
1850 (Const64 <typ.UInt64> [k]))
1851 (Const64 <typ.UInt64> [k]))
1852 ) && k > 0 && k < 7 && kbar == 8 - k
1853 => ((Eq8|Neq8) (And8 <t> n (Const8 <t> [1<<uint(k)-1])) (Const8 <t> [0]))
1854
1855 ((Eq16|Neq16) n (Lsh16x64
1856 (Rsh16x64
1857 (Add16 <t> n (Rsh16Ux64 <t> (Rsh16x64 <t> n (Const64 <typ.UInt64> [15])) (Const64 <typ.UInt64> [kbar])))
1858 (Const64 <typ.UInt64> [k]))
1859 (Const64 <typ.UInt64> [k]))
1860 ) && k > 0 && k < 15 && kbar == 16 - k
1861 => ((Eq16|Neq16) (And16 <t> n (Const16 <t> [1<<uint(k)-1])) (Const16 <t> [0]))
1862
1863 ((Eq32|Neq32) n (Lsh32x64
1864 (Rsh32x64
1865 (Add32 <t> n (Rsh32Ux64 <t> (Rsh32x64 <t> n (Const64 <typ.UInt64> [31])) (Const64 <typ.UInt64> [kbar])))
1866 (Const64 <typ.UInt64> [k]))
1867 (Const64 <typ.UInt64> [k]))
1868 ) && k > 0 && k < 31 && kbar == 32 - k
1869 => ((Eq32|Neq32) (And32 <t> n (Const32 <t> [1<<uint(k)-1])) (Const32 <t> [0]))
1870
1871 ((Eq64|Neq64) n (Lsh64x64
1872 (Rsh64x64
1873 (Add64 <t> n (Rsh64Ux64 <t> (Rsh64x64 <t> n (Const64 <typ.UInt64> [63])) (Const64 <typ.UInt64> [kbar])))
1874 (Const64 <typ.UInt64> [k]))
1875 (Const64 <typ.UInt64> [k]))
1876 ) && k > 0 && k < 63 && kbar == 64 - k
1877 => ((Eq64|Neq64) (And64 <t> n (Const64 <t> [1<<uint(k)-1])) (Const64 <t> [0]))
1878
1879 (Eq(8|16|32|64) s:(Sub(8|16|32|64) x y) (Const(8|16|32|64) [0])) && s.Uses == 1 => (Eq(8|16|32|64) x y)
1880 (Neq(8|16|32|64) s:(Sub(8|16|32|64) x y) (Const(8|16|32|64) [0])) && s.Uses == 1 => (Neq(8|16|32|64) x y)
1881
1882 // Optimize bitsets
1883 (Eq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [y])) && oneBit8(y)
1884 => (Neq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [0]))
1885 (Eq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [y])) && oneBit16(y)
1886 => (Neq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [0]))
1887 (Eq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [y])) && oneBit32(y)
1888 => (Neq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [0]))
1889 (Eq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [y])) && oneBit64(y)
1890 => (Neq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [0]))
1891 (Neq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [y])) && oneBit8(y)
1892 => (Eq8 (And8 <t> x (Const8 <t> [y])) (Const8 <t> [0]))
1893 (Neq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [y])) && oneBit16(y)
1894 => (Eq16 (And16 <t> x (Const16 <t> [y])) (Const16 <t> [0]))
1895 (Neq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [y])) && oneBit32(y)
1896 => (Eq32 (And32 <t> x (Const32 <t> [y])) (Const32 <t> [0]))
1897 (Neq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [y])) && oneBit64(y)
1898 => (Eq64 (And64 <t> x (Const64 <t> [y])) (Const64 <t> [0]))
1899
1900 // Reassociate expressions involving
1901 // constants such that constants come first,
1902 // exposing obvious constant-folding opportunities.
1903 // Reassociate (op (op y C) x) to (op C (op x y)) or similar, where C
1904 // is constant, which pushes constants to the outside
1905 // of the expression. At that point, any constant-folding
1906 // opportunities should be obvious.
1907 // Note: don't include AddPtr here! In order to maintain the
1908 // invariant that pointers must stay within the pointed-to object,
1909 // we can't pull part of a pointer computation above the AddPtr.
1910 // See issue 37881.
1911 // Note: we don't need to handle any (x-C) cases because we already rewrite
1912 // (x-C) to (x+(-C)).
1913
1914 // x + (C + z) -> C + (x + z)
1915 (Add64 (Add64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Add64 <t> z x))
1916 (Add32 (Add32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Add32 <t> z x))
1917 (Add16 (Add16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Add16 <t> z x))
1918 (Add8 (Add8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Add8 i (Add8 <t> z x))
1919
1920 // x + (C - z) -> C + (x - z)
1921 (Add64 (Sub64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Sub64 <t> x z))
1922 (Add32 (Sub32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Sub32 <t> x z))
1923 (Add16 (Sub16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Sub16 <t> x z))
1924 (Add8 (Sub8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Add8 i (Sub8 <t> x z))
1925
1926 // x - (C - z) -> x + (z - C) -> (x + z) - C
1927 (Sub64 x (Sub64 i:(Const64 <t>) z)) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 (Add64 <t> x z) i)
1928 (Sub32 x (Sub32 i:(Const32 <t>) z)) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 (Add32 <t> x z) i)
1929 (Sub16 x (Sub16 i:(Const16 <t>) z)) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 (Add16 <t> x z) i)
1930 (Sub8 x (Sub8 i:(Const8 <t>) z)) && (z.Op != OpConst8 && x.Op != OpConst8) => (Sub8 (Add8 <t> x z) i)
1931
1932 // x - (z + C) -> x + (-z - C) -> (x - z) - C
1933 (Sub64 x (Add64 z i:(Const64 <t>))) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 (Sub64 <t> x z) i)
1934 (Sub32 x (Add32 z i:(Const32 <t>))) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 (Sub32 <t> x z) i)
1935 (Sub16 x (Add16 z i:(Const16 <t>))) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 (Sub16 <t> x z) i)
1936 (Sub8 x (Add8 z i:(Const8 <t>))) && (z.Op != OpConst8 && x.Op != OpConst8) => (Sub8 (Sub8 <t> x z) i)
1937
1938 // (C - z) - x -> C - (z + x)
1939 (Sub64 (Sub64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Sub64 i (Add64 <t> z x))
1940 (Sub32 (Sub32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Sub32 i (Add32 <t> z x))
1941 (Sub16 (Sub16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Sub16 i (Add16 <t> z x))
1942 (Sub8 (Sub8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Sub8 i (Add8 <t> z x))
1943
1944 // (z + C) -x -> C + (z - x)
1945 (Sub64 (Add64 z i:(Const64 <t>)) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Add64 i (Sub64 <t> z x))
1946 (Sub32 (Add32 z i:(Const32 <t>)) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Add32 i (Sub32 <t> z x))
1947 (Sub16 (Add16 z i:(Const16 <t>)) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Add16 i (Sub16 <t> z x))
1948 (Sub8 (Add8 z i:(Const8 <t>)) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Add8 i (Sub8 <t> z x))
1949
1950 // x & (C & z) -> C & (x & z)
1951 (And64 (And64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (And64 i (And64 <t> z x))
1952 (And32 (And32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (And32 i (And32 <t> z x))
1953 (And16 (And16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (And16 i (And16 <t> z x))
1954 (And8 (And8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (And8 i (And8 <t> z x))
1955
1956 // x | (C | z) -> C | (x | z)
1957 (Or64 (Or64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Or64 i (Or64 <t> z x))
1958 (Or32 (Or32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Or32 i (Or32 <t> z x))
1959 (Or16 (Or16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Or16 i (Or16 <t> z x))
1960 (Or8 (Or8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Or8 i (Or8 <t> z x))
1961
1962 // x ^ (C ^ z) -> C ^ (x ^ z)
1963 (Xor64 (Xor64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Xor64 i (Xor64 <t> z x))
1964 (Xor32 (Xor32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Xor32 i (Xor32 <t> z x))
1965 (Xor16 (Xor16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Xor16 i (Xor16 <t> z x))
1966 (Xor8 (Xor8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Xor8 i (Xor8 <t> z x))
1967
1968 // x * (D * z) = D * (x * z)
1969 (Mul64 (Mul64 i:(Const64 <t>) z) x) && (z.Op != OpConst64 && x.Op != OpConst64) => (Mul64 i (Mul64 <t> x z))
1970 (Mul32 (Mul32 i:(Const32 <t>) z) x) && (z.Op != OpConst32 && x.Op != OpConst32) => (Mul32 i (Mul32 <t> x z))
1971 (Mul16 (Mul16 i:(Const16 <t>) z) x) && (z.Op != OpConst16 && x.Op != OpConst16) => (Mul16 i (Mul16 <t> x z))
1972 (Mul8 (Mul8 i:(Const8 <t>) z) x) && (z.Op != OpConst8 && x.Op != OpConst8) => (Mul8 i (Mul8 <t> x z))
1973
1974 // C + (D + x) -> (C + D) + x
1975 (Add64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Add64 (Const64 <t> [c+d]) x)
1976 (Add32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Add32 (Const32 <t> [c+d]) x)
1977 (Add16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Add16 (Const16 <t> [c+d]) x)
1978 (Add8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Add8 (Const8 <t> [c+d]) x)
1979
1980 // C + (D - x) -> (C + D) - x
1981 (Add64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) => (Sub64 (Const64 <t> [c+d]) x)
1982 (Add32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) => (Sub32 (Const32 <t> [c+d]) x)
1983 (Add16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) => (Sub16 (Const16 <t> [c+d]) x)
1984 (Add8 (Const8 <t> [c]) (Sub8 (Const8 <t> [d]) x)) => (Sub8 (Const8 <t> [c+d]) x)
1985
1986 // C - (D - x) -> (C - D) + x
1987 (Sub64 (Const64 <t> [c]) (Sub64 (Const64 <t> [d]) x)) => (Add64 (Const64 <t> [c-d]) x)
1988 (Sub32 (Const32 <t> [c]) (Sub32 (Const32 <t> [d]) x)) => (Add32 (Const32 <t> [c-d]) x)
1989 (Sub16 (Const16 <t> [c]) (Sub16 (Const16 <t> [d]) x)) => (Add16 (Const16 <t> [c-d]) x)
1990 (Sub8 (Const8 <t> [c]) (Sub8 (Const8 <t> [d]) x)) => (Add8 (Const8 <t> [c-d]) x)
1991
1992 // C - (D + x) -> (C - D) - x
1993 (Sub64 (Const64 <t> [c]) (Add64 (Const64 <t> [d]) x)) => (Sub64 (Const64 <t> [c-d]) x)
1994 (Sub32 (Const32 <t> [c]) (Add32 (Const32 <t> [d]) x)) => (Sub32 (Const32 <t> [c-d]) x)
1995 (Sub16 (Const16 <t> [c]) (Add16 (Const16 <t> [d]) x)) => (Sub16 (Const16 <t> [c-d]) x)
1996 (Sub8 (Const8 <t> [c]) (Add8 (Const8 <t> [d]) x)) => (Sub8 (Const8 <t> [c-d]) x)
1997
1998 // C & (D & x) -> (C & D) & x
1999 (And64 (Const64 <t> [c]) (And64 (Const64 <t> [d]) x)) => (And64 (Const64 <t> [c&d]) x)
2000 (And32 (Const32 <t> [c]) (And32 (Const32 <t> [d]) x)) => (And32 (Const32 <t> [c&d]) x)
2001 (And16 (Const16 <t> [c]) (And16 (Const16 <t> [d]) x)) => (And16 (Const16 <t> [c&d]) x)
2002 (And8 (Const8 <t> [c]) (And8 (Const8 <t> [d]) x)) => (And8 (Const8 <t> [c&d]) x)
2003
2004 // C | (D | x) -> (C | D) | x
2005 (Or64 (Const64 <t> [c]) (Or64 (Const64 <t> [d]) x)) => (Or64 (Const64 <t> [c|d]) x)
2006 (Or32 (Const32 <t> [c]) (Or32 (Const32 <t> [d]) x)) => (Or32 (Const32 <t> [c|d]) x)
2007 (Or16 (Const16 <t> [c]) (Or16 (Const16 <t> [d]) x)) => (Or16 (Const16 <t> [c|d]) x)
2008 (Or8 (Const8 <t> [c]) (Or8 (Const8 <t> [d]) x)) => (Or8 (Const8 <t> [c|d]) x)
2009
2010 // C ^ (D ^ x) -> (C ^ D) ^ x
2011 (Xor64 (Const64 <t> [c]) (Xor64 (Const64 <t> [d]) x)) => (Xor64 (Const64 <t> [c^d]) x)
2012 (Xor32 (Const32 <t> [c]) (Xor32 (Const32 <t> [d]) x)) => (Xor32 (Const32 <t> [c^d]) x)
2013 (Xor16 (Const16 <t> [c]) (Xor16 (Const16 <t> [d]) x)) => (Xor16 (Const16 <t> [c^d]) x)
2014 (Xor8 (Const8 <t> [c]) (Xor8 (Const8 <t> [d]) x)) => (Xor8 (Const8 <t> [c^d]) x)
2015
2016 // C * (D * x) = (C * D) * x
2017 (Mul64 (Const64 <t> [c]) (Mul64 (Const64 <t> [d]) x)) => (Mul64 (Const64 <t> [c*d]) x)
2018 (Mul32 (Const32 <t> [c]) (Mul32 (Const32 <t> [d]) x)) => (Mul32 (Const32 <t> [c*d]) x)
2019 (Mul16 (Const16 <t> [c]) (Mul16 (Const16 <t> [d]) x)) => (Mul16 (Const16 <t> [c*d]) x)
2020 (Mul8 (Const8 <t> [c]) (Mul8 (Const8 <t> [d]) x)) => (Mul8 (Const8 <t> [c*d]) x)
2021
2022 // floating point optimizations
2023 (Mul(32|64)F x (Const(32|64)F [1])) => x
2024 (Mul32F x (Const32F [-1])) => (Neg32F x)
2025 (Mul64F x (Const64F [-1])) => (Neg64F x)
2026 (Mul32F x (Const32F [2])) => (Add32F x x)
2027 (Mul64F x (Const64F [2])) => (Add64F x x)
2028
2029 (Div32F x (Const32F <t> [c])) && reciprocalExact32(c) => (Mul32F x (Const32F <t> [1/c]))
2030 (Div64F x (Const64F <t> [c])) && reciprocalExact64(c) => (Mul64F x (Const64F <t> [1/c]))
2031
2032 // rewrite single-precision sqrt expression "float32(math.Sqrt(float64(x)))"
2033 (Cvt64Fto32F sqrt0:(Sqrt (Cvt32Fto64F x))) && sqrt0.Uses==1 => (Sqrt32 x)
2034
2035 (Sqrt (Const64F [c])) && !math.IsNaN(math.Sqrt(c)) => (Const64F [math.Sqrt(c)])
2036
2037 // for rewriting results of some late-expanded rewrites (below)
2038 (SelectN [0] (MakeResult x ___)) => x
2039 (SelectN [1] (MakeResult x y ___)) => y
2040 (SelectN [2] (MakeResult x y z ___)) => z
2041
2042 // for late-expanded calls, recognize newobject and remove zeroing and nilchecks
2043 (Zero (SelectN [0] call:(StaticLECall _ _)) mem:(SelectN [1] call))
2044 && isSameCall(call.Aux, "runtime.newobject")
2045 => mem
2046
2047 (Store (SelectN [0] call:(StaticLECall _ _)) x mem:(SelectN [1] call))
2048 && isConstZero(x)
2049 && isSameCall(call.Aux, "runtime.newobject")
2050 => mem
2051
2052 (Store (OffPtr (SelectN [0] call:(StaticLECall _ _))) x mem:(SelectN [1] call))
2053 && isConstZero(x)
2054 && isSameCall(call.Aux, "runtime.newobject")
2055 => mem
2056
2057 (NilCheck ptr:(SelectN [0] call:(StaticLECall _ _)) _)
2058 && isSameCall(call.Aux, "runtime.newobject")
2059 && warnRule(fe.Debug_checknil(), v, "removed nil check")
2060 => ptr
2061
2062 (NilCheck ptr:(OffPtr (SelectN [0] call:(StaticLECall _ _))) _)
2063 && isSameCall(call.Aux, "runtime.newobject")
2064 && warnRule(fe.Debug_checknil(), v, "removed nil check")
2065 => ptr
2066
2067 // Addresses of globals are always non-nil.
2068 (NilCheck ptr:(Addr {_} (SB)) _) => ptr
2069 (NilCheck ptr:(Convert (Addr {_} (SB)) _) _) => ptr
2070
2071 // Nil checks of nil checks are redundant.
2072 // See comment at the end of https://go-review.googlesource.com/c/go/+/537775.
2073 (NilCheck ptr:(NilCheck _ _) _ ) => ptr
2074
2075 // for late-expanded calls, recognize memequal applied to a single constant byte
2076 // Support is limited by 1, 2, 4, 8 byte sizes
2077 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [1]) mem)
2078 && isSameCall(callAux, "runtime.memequal")
2079 && symIsRO(scon)
2080 => (MakeResult (Eq8 (Load <typ.Int8> sptr mem) (Const8 <typ.Int8> [int8(read8(scon,0))])) mem)
2081
2082 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [1]) mem)
2083 && isSameCall(callAux, "runtime.memequal")
2084 && symIsRO(scon)
2085 => (MakeResult (Eq8 (Load <typ.Int8> sptr mem) (Const8 <typ.Int8> [int8(read8(scon,0))])) mem)
2086
2087 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [2]) mem)
2088 && isSameCall(callAux, "runtime.memequal")
2089 && symIsRO(scon)
2090 && canLoadUnaligned(config)
2091 => (MakeResult (Eq16 (Load <typ.Int16> sptr mem) (Const16 <typ.Int16> [int16(read16(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2092
2093 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [2]) mem)
2094 && isSameCall(callAux, "runtime.memequal")
2095 && symIsRO(scon)
2096 && canLoadUnaligned(config)
2097 => (MakeResult (Eq16 (Load <typ.Int16> sptr mem) (Const16 <typ.Int16> [int16(read16(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2098
2099 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [4]) mem)
2100 && isSameCall(callAux, "runtime.memequal")
2101 && symIsRO(scon)
2102 && canLoadUnaligned(config)
2103 => (MakeResult (Eq32 (Load <typ.Int32> sptr mem) (Const32 <typ.Int32> [int32(read32(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2104
2105 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [4]) mem)
2106 && isSameCall(callAux, "runtime.memequal")
2107 && symIsRO(scon)
2108 && canLoadUnaligned(config)
2109 => (MakeResult (Eq32 (Load <typ.Int32> sptr mem) (Const32 <typ.Int32> [int32(read32(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2110
2111 (StaticLECall {callAux} sptr (Addr {scon} (SB)) (Const64 [8]) mem)
2112 && isSameCall(callAux, "runtime.memequal")
2113 && symIsRO(scon)
2114 && canLoadUnaligned(config) && config.PtrSize == 8
2115 => (MakeResult (Eq64 (Load <typ.Int64> sptr mem) (Const64 <typ.Int64> [int64(read64(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2116
2117 (StaticLECall {callAux} (Addr {scon} (SB)) sptr (Const64 [8]) mem)
2118 && isSameCall(callAux, "runtime.memequal")
2119 && symIsRO(scon)
2120 && canLoadUnaligned(config) && config.PtrSize == 8
2121 => (MakeResult (Eq64 (Load <typ.Int64> sptr mem) (Const64 <typ.Int64> [int64(read64(scon,0,config.ctxt.Arch.ByteOrder))])) mem)
2122
2123 (StaticLECall {callAux} _ _ (Const64 [0]) mem)
2124 && isSameCall(callAux, "runtime.memequal")
2125 => (MakeResult (ConstBool <typ.Bool> [true]) mem)
2126
2127 (Static(Call|LECall) {callAux} p q _ mem)
2128 && isSameCall(callAux, "runtime.memequal")
2129 && isSamePtr(p, q)
2130 => (MakeResult (ConstBool <typ.Bool> [true]) mem)
2131
2132 // Turn known-size calls to memclrNoHeapPointers into a Zero.
2133 // Note that we are using types.Types[types.TUINT8] instead of sptr.Type.Elem() - see issue 55122 and CL 431496 for more details.
2134 (SelectN [0] call:(StaticCall {sym} sptr (Const(64|32) [c]) mem))
2135 && isInlinableMemclr(config, int64(c))
2136 && isSameCall(sym, "runtime.memclrNoHeapPointers")
2137 && call.Uses == 1
2138 && clobber(call)
2139 => (Zero {types.Types[types.TUINT8]} [int64(c)] sptr mem)
2140
2141 // Recognise make([]T, 0) and replace it with a pointer to the zerobase
2142 (StaticLECall {callAux} _ (Const(64|32) [0]) (Const(64|32) [0]) mem)
2143 && isSameCall(callAux, "runtime.makeslice")
2144 => (MakeResult (Addr <v.Type.FieldType(0)> {ir.Syms.Zerobase} (SB)) mem)
2145
2146 // Evaluate constant address comparisons.
2147 (EqPtr x x) => (ConstBool [true])
2148 (NeqPtr x x) => (ConstBool [false])
2149 (EqPtr (Addr {x} _) (Addr {y} _)) => (ConstBool [x == y])
2150 (EqPtr (Addr {x} _) (OffPtr [o] (Addr {y} _))) => (ConstBool [x == y && o == 0])
2151 (EqPtr (OffPtr [o1] (Addr {x} _)) (OffPtr [o2] (Addr {y} _))) => (ConstBool [x == y && o1 == o2])
2152 (NeqPtr (Addr {x} _) (Addr {y} _)) => (ConstBool [x != y])
2153 (NeqPtr (Addr {x} _) (OffPtr [o] (Addr {y} _))) => (ConstBool [x != y || o != 0])
2154 (NeqPtr (OffPtr [o1] (Addr {x} _)) (OffPtr [o2] (Addr {y} _))) => (ConstBool [x != y || o1 != o2])
2155 (EqPtr (LocalAddr {x} _ _) (LocalAddr {y} _ _)) => (ConstBool [x == y])
2156 (EqPtr (LocalAddr {x} _ _) (OffPtr [o] (LocalAddr {y} _ _))) => (ConstBool [x == y && o == 0])
2157 (EqPtr (OffPtr [o1] (LocalAddr {x} _ _)) (OffPtr [o2] (LocalAddr {y} _ _))) => (ConstBool [x == y && o1 == o2])
2158 (NeqPtr (LocalAddr {x} _ _) (LocalAddr {y} _ _)) => (ConstBool [x != y])
2159 (NeqPtr (LocalAddr {x} _ _) (OffPtr [o] (LocalAddr {y} _ _))) => (ConstBool [x != y || o != 0])
2160 (NeqPtr (OffPtr [o1] (LocalAddr {x} _ _)) (OffPtr [o2] (LocalAddr {y} _ _))) => (ConstBool [x != y || o1 != o2])
2161 (EqPtr (OffPtr [o1] p1) p2) && isSamePtr(p1, p2) => (ConstBool [o1 == 0])
2162 (NeqPtr (OffPtr [o1] p1) p2) && isSamePtr(p1, p2) => (ConstBool [o1 != 0])
2163 (EqPtr (OffPtr [o1] p1) (OffPtr [o2] p2)) && isSamePtr(p1, p2) => (ConstBool [o1 == o2])
2164 (NeqPtr (OffPtr [o1] p1) (OffPtr [o2] p2)) && isSamePtr(p1, p2) => (ConstBool [o1 != o2])
2165 (EqPtr (Const(32|64) [c]) (Const(32|64) [d])) => (ConstBool [c == d])
2166 (NeqPtr (Const(32|64) [c]) (Const(32|64) [d])) => (ConstBool [c != d])
2167 (EqPtr (Convert (Addr {x} _) _) (Addr {y} _)) => (ConstBool [x==y])
2168 (NeqPtr (Convert (Addr {x} _) _) (Addr {y} _)) => (ConstBool [x!=y])
2169
2170 (EqPtr (LocalAddr _ _) (Addr _)) => (ConstBool [false])
2171 (EqPtr (OffPtr (LocalAddr _ _)) (Addr _)) => (ConstBool [false])
2172 (EqPtr (LocalAddr _ _) (OffPtr (Addr _))) => (ConstBool [false])
2173 (EqPtr (OffPtr (LocalAddr _ _)) (OffPtr (Addr _))) => (ConstBool [false])
2174 (NeqPtr (LocalAddr _ _) (Addr _)) => (ConstBool [true])
2175 (NeqPtr (OffPtr (LocalAddr _ _)) (Addr _)) => (ConstBool [true])
2176 (NeqPtr (LocalAddr _ _) (OffPtr (Addr _))) => (ConstBool [true])
2177 (NeqPtr (OffPtr (LocalAddr _ _)) (OffPtr (Addr _))) => (ConstBool [true])
2178
2179 // Simplify address comparisons.
2180 (EqPtr (AddPtr p1 o1) p2) && isSamePtr(p1, p2) => (Not (IsNonNil o1))
2181 (NeqPtr (AddPtr p1 o1) p2) && isSamePtr(p1, p2) => (IsNonNil o1)
2182 (EqPtr (Const(32|64) [0]) p) => (Not (IsNonNil p))
2183 (NeqPtr (Const(32|64) [0]) p) => (IsNonNil p)
2184 (EqPtr (ConstNil) p) => (Not (IsNonNil p))
2185 (NeqPtr (ConstNil) p) => (IsNonNil p)
2186
2187 // Evaluate constant user nil checks.
2188 (IsNonNil (ConstNil)) => (ConstBool [false])
2189 (IsNonNil (Const(32|64) [c])) => (ConstBool [c != 0])
2190 (IsNonNil (Addr _) ) => (ConstBool [true])
2191 (IsNonNil (Convert (Addr _) _)) => (ConstBool [true])
2192 (IsNonNil (LocalAddr _ _)) => (ConstBool [true])
2193
2194 // Inline small or disjoint runtime.memmove calls with constant length.
2195 // See the comment in op Move in genericOps.go for discussion of the type.
2196 //
2197 // Note that we've lost any knowledge of the type and alignment requirements
2198 // of the source and destination. We only know the size, and that the type
2199 // contains no pointers.
2200 // The type of the move is not necessarily v.Args[0].Type().Elem()!
2201 // See issue 55122 for details.
2202 //
2203 // Because expand calls runs after prove, constants useful to this pattern may not appear.
2204 // Both versions need to exist; the memory and register variants.
2205 //
2206 // Match post-expansion calls, memory version.
2207 (SelectN [0] call:(StaticCall {sym} s1:(Store _ (Const(64|32) [sz]) s2:(Store _ src s3:(Store {t} _ dst mem)))))
2208 && sz >= 0
2209 && isSameCall(sym, "runtime.memmove")
2210 && s1.Uses == 1 && s2.Uses == 1 && s3.Uses == 1
2211 && isInlinableMemmove(dst, src, int64(sz), config)
2212 && clobber(s1, s2, s3, call)
2213 => (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
2214
2215 // Match post-expansion calls, register version.
2216 (SelectN [0] call:(StaticCall {sym} dst src (Const(64|32) [sz]) mem))
2217 && sz >= 0
2218 && call.Uses == 1 // this will exclude all calls with results
2219 && isSameCall(sym, "runtime.memmove")
2220 && isInlinableMemmove(dst, src, int64(sz), config)
2221 && clobber(call)
2222 => (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
2223
2224 // Match pre-expansion calls.
2225 (SelectN [0] call:(StaticLECall {sym} dst src (Const(64|32) [sz]) mem))
2226 && sz >= 0
2227 && call.Uses == 1 // this will exclude all calls with results
2228 && isSameCall(sym, "runtime.memmove")
2229 && isInlinableMemmove(dst, src, int64(sz), config)
2230 && clobber(call)
2231 => (Move {types.Types[types.TUINT8]} [int64(sz)] dst src mem)
2232
2233 // De-virtualize late-expanded interface calls into late-expanded static calls.
2234 (InterLECall [argsize] {auxCall} (Addr {fn} (SB)) ___) => devirtLECall(v, fn.(*obj.LSym))
2235
2236 // Move and Zero optimizations.
2237 // Move source and destination may overlap.
2238
2239 // Convert Moves into Zeros when the source is known to be zeros.
2240 (Move {t} [n] dst1 src mem:(Zero {t} [n] dst2 _)) && isSamePtr(src, dst2)
2241 => (Zero {t} [n] dst1 mem)
2242 (Move {t} [n] dst1 src mem:(VarDef (Zero {t} [n] dst0 _))) && isSamePtr(src, dst0)
2243 => (Zero {t} [n] dst1 mem)
2244 (Move {t} [n] dst (Addr {sym} (SB)) mem) && symIsROZero(sym) => (Zero {t} [n] dst mem)
2245
2246 // Don't Store to variables that are about to be overwritten by Move/Zero.
2247 (Zero {t1} [n] p1 store:(Store {t2} (OffPtr [o2] p2) _ mem))
2248 && isSamePtr(p1, p2) && store.Uses == 1
2249 && n >= o2 + t2.Size()
2250 && clobber(store)
2251 => (Zero {t1} [n] p1 mem)
2252 (Move {t1} [n] dst1 src1 store:(Store {t2} op:(OffPtr [o2] dst2) _ mem))
2253 && isSamePtr(dst1, dst2) && store.Uses == 1
2254 && n >= o2 + t2.Size()
2255 && disjoint(src1, n, op, t2.Size())
2256 && clobber(store)
2257 => (Move {t1} [n] dst1 src1 mem)
2258
2259 // Don't Move to variables that are immediately completely overwritten.
2260 (Zero {t} [n] dst1 move:(Move {t} [n] dst2 _ mem))
2261 && move.Uses == 1
2262 && isSamePtr(dst1, dst2)
2263 && clobber(move)
2264 => (Zero {t} [n] dst1 mem)
2265 (Move {t} [n] dst1 src1 move:(Move {t} [n] dst2 _ mem))
2266 && move.Uses == 1
2267 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2268 && clobber(move)
2269 => (Move {t} [n] dst1 src1 mem)
2270 (Zero {t} [n] dst1 vardef:(VarDef {x} move:(Move {t} [n] dst2 _ mem)))
2271 && move.Uses == 1 && vardef.Uses == 1
2272 && isSamePtr(dst1, dst2)
2273 && clobber(move, vardef)
2274 => (Zero {t} [n] dst1 (VarDef {x} mem))
2275 (Move {t} [n] dst1 src1 vardef:(VarDef {x} move:(Move {t} [n] dst2 _ mem)))
2276 && move.Uses == 1 && vardef.Uses == 1
2277 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2278 && clobber(move, vardef)
2279 => (Move {t} [n] dst1 src1 (VarDef {x} mem))
2280 (Store {t1} op1:(OffPtr [o1] p1) d1
2281 m2:(Store {t2} op2:(OffPtr [0] p2) d2
2282 m3:(Move [n] p3 _ mem)))
2283 && m2.Uses == 1 && m3.Uses == 1
2284 && o1 == t2.Size()
2285 && n == t2.Size() + t1.Size()
2286 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2287 && clobber(m2, m3)
2288 => (Store {t1} op1 d1 (Store {t2} op2 d2 mem))
2289 (Store {t1} op1:(OffPtr [o1] p1) d1
2290 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2291 m3:(Store {t3} op3:(OffPtr [0] p3) d3
2292 m4:(Move [n] p4 _ mem))))
2293 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1
2294 && o2 == t3.Size()
2295 && o1-o2 == t2.Size()
2296 && n == t3.Size() + t2.Size() + t1.Size()
2297 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2298 && clobber(m2, m3, m4)
2299 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 mem)))
2300 (Store {t1} op1:(OffPtr [o1] p1) d1
2301 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2302 m3:(Store {t3} op3:(OffPtr [o3] p3) d3
2303 m4:(Store {t4} op4:(OffPtr [0] p4) d4
2304 m5:(Move [n] p5 _ mem)))))
2305 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1 && m5.Uses == 1
2306 && o3 == t4.Size()
2307 && o2-o3 == t3.Size()
2308 && o1-o2 == t2.Size()
2309 && n == t4.Size() + t3.Size() + t2.Size() + t1.Size()
2310 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2311 && clobber(m2, m3, m4, m5)
2312 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 (Store {t4} op4 d4 mem))))
2313
2314 // Don't Zero variables that are immediately completely overwritten
2315 // before being accessed.
2316 (Move {t} [n] dst1 src1 zero:(Zero {t} [n] dst2 mem))
2317 && zero.Uses == 1
2318 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2319 && clobber(zero)
2320 => (Move {t} [n] dst1 src1 mem)
2321 (Move {t} [n] dst1 src1 vardef:(VarDef {x} zero:(Zero {t} [n] dst2 mem)))
2322 && zero.Uses == 1 && vardef.Uses == 1
2323 && isSamePtr(dst1, dst2) && disjoint(src1, n, dst2, n)
2324 && clobber(zero, vardef)
2325 => (Move {t} [n] dst1 src1 (VarDef {x} mem))
2326 (Store {t1} op1:(OffPtr [o1] p1) d1
2327 m2:(Store {t2} op2:(OffPtr [0] p2) d2
2328 m3:(Zero [n] p3 mem)))
2329 && m2.Uses == 1 && m3.Uses == 1
2330 && o1 == t2.Size()
2331 && n == t2.Size() + t1.Size()
2332 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2333 && clobber(m2, m3)
2334 => (Store {t1} op1 d1 (Store {t2} op2 d2 mem))
2335 (Store {t1} op1:(OffPtr [o1] p1) d1
2336 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2337 m3:(Store {t3} op3:(OffPtr [0] p3) d3
2338 m4:(Zero [n] p4 mem))))
2339 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1
2340 && o2 == t3.Size()
2341 && o1-o2 == t2.Size()
2342 && n == t3.Size() + t2.Size() + t1.Size()
2343 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2344 && clobber(m2, m3, m4)
2345 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 mem)))
2346 (Store {t1} op1:(OffPtr [o1] p1) d1
2347 m2:(Store {t2} op2:(OffPtr [o2] p2) d2
2348 m3:(Store {t3} op3:(OffPtr [o3] p3) d3
2349 m4:(Store {t4} op4:(OffPtr [0] p4) d4
2350 m5:(Zero [n] p5 mem)))))
2351 && m2.Uses == 1 && m3.Uses == 1 && m4.Uses == 1 && m5.Uses == 1
2352 && o3 == t4.Size()
2353 && o2-o3 == t3.Size()
2354 && o1-o2 == t2.Size()
2355 && n == t4.Size() + t3.Size() + t2.Size() + t1.Size()
2356 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2357 && clobber(m2, m3, m4, m5)
2358 => (Store {t1} op1 d1 (Store {t2} op2 d2 (Store {t3} op3 d3 (Store {t4} op4 d4 mem))))
2359
2360 // Don't Move from memory if the values are likely to already be
2361 // in registers.
2362 (Move {t1} [n] dst p1
2363 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2364 (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _)))
2365 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2366 && t2.Alignment() <= t1.Alignment()
2367 && t3.Alignment() <= t1.Alignment()
2368 && registerizable(b, t2)
2369 && registerizable(b, t3)
2370 && o2 == t3.Size()
2371 && n == t2.Size() + t3.Size()
2372 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2373 (Store {t3} (OffPtr <tt3> [0] dst) d2 mem))
2374 (Move {t1} [n] dst p1
2375 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2376 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2377 (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _))))
2378 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2379 && t2.Alignment() <= t1.Alignment()
2380 && t3.Alignment() <= t1.Alignment()
2381 && t4.Alignment() <= t1.Alignment()
2382 && registerizable(b, t2)
2383 && registerizable(b, t3)
2384 && registerizable(b, t4)
2385 && o3 == t4.Size()
2386 && o2-o3 == t3.Size()
2387 && n == t2.Size() + t3.Size() + t4.Size()
2388 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2389 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2390 (Store {t4} (OffPtr <tt4> [0] dst) d3 mem)))
2391 (Move {t1} [n] dst p1
2392 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2393 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2394 (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3
2395 (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _)))))
2396 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2397 && t2.Alignment() <= t1.Alignment()
2398 && t3.Alignment() <= t1.Alignment()
2399 && t4.Alignment() <= t1.Alignment()
2400 && t5.Alignment() <= t1.Alignment()
2401 && registerizable(b, t2)
2402 && registerizable(b, t3)
2403 && registerizable(b, t4)
2404 && registerizable(b, t5)
2405 && o4 == t5.Size()
2406 && o3-o4 == t4.Size()
2407 && o2-o3 == t3.Size()
2408 && n == t2.Size() + t3.Size() + t4.Size() + t5.Size()
2409 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2410 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2411 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2412 (Store {t5} (OffPtr <tt5> [0] dst) d4 mem))))
2413
2414 // Same thing but with VarDef in the middle.
2415 (Move {t1} [n] dst p1
2416 mem:(VarDef
2417 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2418 (Store {t3} op3:(OffPtr <tt3> [0] p3) d2 _))))
2419 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2420 && t2.Alignment() <= t1.Alignment()
2421 && t3.Alignment() <= t1.Alignment()
2422 && registerizable(b, t2)
2423 && registerizable(b, t3)
2424 && o2 == t3.Size()
2425 && n == t2.Size() + t3.Size()
2426 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2427 (Store {t3} (OffPtr <tt3> [0] dst) d2 mem))
2428 (Move {t1} [n] dst p1
2429 mem:(VarDef
2430 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2431 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2432 (Store {t4} op4:(OffPtr <tt4> [0] p4) d3 _)))))
2433 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2434 && t2.Alignment() <= t1.Alignment()
2435 && t3.Alignment() <= t1.Alignment()
2436 && t4.Alignment() <= t1.Alignment()
2437 && registerizable(b, t2)
2438 && registerizable(b, t3)
2439 && registerizable(b, t4)
2440 && o3 == t4.Size()
2441 && o2-o3 == t3.Size()
2442 && n == t2.Size() + t3.Size() + t4.Size()
2443 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2444 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2445 (Store {t4} (OffPtr <tt4> [0] dst) d3 mem)))
2446 (Move {t1} [n] dst p1
2447 mem:(VarDef
2448 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2449 (Store {t3} op3:(OffPtr <tt3> [o3] p3) d2
2450 (Store {t4} op4:(OffPtr <tt4> [o4] p4) d3
2451 (Store {t5} op5:(OffPtr <tt5> [0] p5) d4 _))))))
2452 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2453 && t2.Alignment() <= t1.Alignment()
2454 && t3.Alignment() <= t1.Alignment()
2455 && t4.Alignment() <= t1.Alignment()
2456 && t5.Alignment() <= t1.Alignment()
2457 && registerizable(b, t2)
2458 && registerizable(b, t3)
2459 && registerizable(b, t4)
2460 && registerizable(b, t5)
2461 && o4 == t5.Size()
2462 && o3-o4 == t4.Size()
2463 && o2-o3 == t3.Size()
2464 && n == t2.Size() + t3.Size() + t4.Size() + t5.Size()
2465 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2466 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2467 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2468 (Store {t5} (OffPtr <tt5> [0] dst) d4 mem))))
2469
2470 // Prefer to Zero and Store than to Move.
2471 (Move {t1} [n] dst p1
2472 mem:(Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2473 (Zero {t3} [n] p3 _)))
2474 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2475 && t2.Alignment() <= t1.Alignment()
2476 && t3.Alignment() <= t1.Alignment()
2477 && registerizable(b, t2)
2478 && n >= o2 + t2.Size()
2479 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2480 (Zero {t1} [n] dst mem))
2481 (Move {t1} [n] dst p1
2482 mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
2483 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2484 (Zero {t4} [n] p4 _))))
2485 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2486 && t2.Alignment() <= t1.Alignment()
2487 && t3.Alignment() <= t1.Alignment()
2488 && t4.Alignment() <= t1.Alignment()
2489 && registerizable(b, t2)
2490 && registerizable(b, t3)
2491 && n >= o2 + t2.Size()
2492 && n >= o3 + t3.Size()
2493 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2494 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2495 (Zero {t1} [n] dst mem)))
2496 (Move {t1} [n] dst p1
2497 mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
2498 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2499 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2500 (Zero {t5} [n] p5 _)))))
2501 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2502 && t2.Alignment() <= t1.Alignment()
2503 && t3.Alignment() <= t1.Alignment()
2504 && t4.Alignment() <= t1.Alignment()
2505 && t5.Alignment() <= t1.Alignment()
2506 && registerizable(b, t2)
2507 && registerizable(b, t3)
2508 && registerizable(b, t4)
2509 && n >= o2 + t2.Size()
2510 && n >= o3 + t3.Size()
2511 && n >= o4 + t4.Size()
2512 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2513 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2514 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2515 (Zero {t1} [n] dst mem))))
2516 (Move {t1} [n] dst p1
2517 mem:(Store {t2} (OffPtr <tt2> [o2] p2) d1
2518 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2519 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2520 (Store {t5} (OffPtr <tt5> [o5] p5) d4
2521 (Zero {t6} [n] p6 _))))))
2522 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && isSamePtr(p5, p6)
2523 && t2.Alignment() <= t1.Alignment()
2524 && t3.Alignment() <= t1.Alignment()
2525 && t4.Alignment() <= t1.Alignment()
2526 && t5.Alignment() <= t1.Alignment()
2527 && t6.Alignment() <= t1.Alignment()
2528 && registerizable(b, t2)
2529 && registerizable(b, t3)
2530 && registerizable(b, t4)
2531 && registerizable(b, t5)
2532 && n >= o2 + t2.Size()
2533 && n >= o3 + t3.Size()
2534 && n >= o4 + t4.Size()
2535 && n >= o5 + t5.Size()
2536 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2537 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2538 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2539 (Store {t5} (OffPtr <tt5> [o5] dst) d4
2540 (Zero {t1} [n] dst mem)))))
2541 (Move {t1} [n] dst p1
2542 mem:(VarDef
2543 (Store {t2} op2:(OffPtr <tt2> [o2] p2) d1
2544 (Zero {t3} [n] p3 _))))
2545 && isSamePtr(p1, p2) && isSamePtr(p2, p3)
2546 && t2.Alignment() <= t1.Alignment()
2547 && t3.Alignment() <= t1.Alignment()
2548 && registerizable(b, t2)
2549 && n >= o2 + t2.Size()
2550 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2551 (Zero {t1} [n] dst mem))
2552 (Move {t1} [n] dst p1
2553 mem:(VarDef
2554 (Store {t2} (OffPtr <tt2> [o2] p2) d1
2555 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2556 (Zero {t4} [n] p4 _)))))
2557 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4)
2558 && t2.Alignment() <= t1.Alignment()
2559 && t3.Alignment() <= t1.Alignment()
2560 && t4.Alignment() <= t1.Alignment()
2561 && registerizable(b, t2)
2562 && registerizable(b, t3)
2563 && n >= o2 + t2.Size()
2564 && n >= o3 + t3.Size()
2565 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2566 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2567 (Zero {t1} [n] dst mem)))
2568 (Move {t1} [n] dst p1
2569 mem:(VarDef
2570 (Store {t2} (OffPtr <tt2> [o2] p2) d1
2571 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2572 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2573 (Zero {t5} [n] p5 _))))))
2574 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5)
2575 && t2.Alignment() <= t1.Alignment()
2576 && t3.Alignment() <= t1.Alignment()
2577 && t4.Alignment() <= t1.Alignment()
2578 && t5.Alignment() <= t1.Alignment()
2579 && registerizable(b, t2)
2580 && registerizable(b, t3)
2581 && registerizable(b, t4)
2582 && n >= o2 + t2.Size()
2583 && n >= o3 + t3.Size()
2584 && n >= o4 + t4.Size()
2585 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2586 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2587 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2588 (Zero {t1} [n] dst mem))))
2589 (Move {t1} [n] dst p1
2590 mem:(VarDef
2591 (Store {t2} (OffPtr <tt2> [o2] p2) d1
2592 (Store {t3} (OffPtr <tt3> [o3] p3) d2
2593 (Store {t4} (OffPtr <tt4> [o4] p4) d3
2594 (Store {t5} (OffPtr <tt5> [o5] p5) d4
2595 (Zero {t6} [n] p6 _)))))))
2596 && isSamePtr(p1, p2) && isSamePtr(p2, p3) && isSamePtr(p3, p4) && isSamePtr(p4, p5) && isSamePtr(p5, p6)
2597 && t2.Alignment() <= t1.Alignment()
2598 && t3.Alignment() <= t1.Alignment()
2599 && t4.Alignment() <= t1.Alignment()
2600 && t5.Alignment() <= t1.Alignment()
2601 && t6.Alignment() <= t1.Alignment()
2602 && registerizable(b, t2)
2603 && registerizable(b, t3)
2604 && registerizable(b, t4)
2605 && registerizable(b, t5)
2606 && n >= o2 + t2.Size()
2607 && n >= o3 + t3.Size()
2608 && n >= o4 + t4.Size()
2609 && n >= o5 + t5.Size()
2610 => (Store {t2} (OffPtr <tt2> [o2] dst) d1
2611 (Store {t3} (OffPtr <tt3> [o3] dst) d2
2612 (Store {t4} (OffPtr <tt4> [o4] dst) d3
2613 (Store {t5} (OffPtr <tt5> [o5] dst) d4
2614 (Zero {t1} [n] dst mem)))))
2615
2616 (SelectN [0] call:(StaticLECall {sym} a x)) && needRaceCleanup(sym, call) && clobber(call) => x
2617 (SelectN [0] call:(StaticLECall {sym} x)) && needRaceCleanup(sym, call) && clobber(call) => x
2618
2619 // When rewriting append to growslice, we use as the new length the result of
2620 // growslice so that we don't have to spill/restore the new length around the growslice call.
2621 // The exception here is that if the new length is a constant, avoiding spilling it
2622 // is pointless and its constantness is sometimes useful for subsequent optimizations.
2623 // See issue 56440.
2624 // Note there are 2 rules here, one for the pre-decomposed []T result and one for
2625 // the post-decomposed (*T,int,int) result. (The latter is generated after call expansion.)
2626 (SliceLen (SelectN [0] (StaticLECall {sym} _ newLen:(Const(64|32)) _ _ _ _))) && isSameCall(sym, "runtime.growslice") => newLen
2627 (SelectN [1] (StaticCall {sym} _ newLen:(Const(64|32)) _ _ _ _)) && v.Type.IsInteger() && isSameCall(sym, "runtime.growslice") => newLen
2628
2629 // Collapse moving A -> B -> C into just A -> C.
2630 // Later passes (deadstore, elim unread auto) will remove the A -> B move, if possible.
2631 // This happens most commonly when B is an autotmp inserted earlier
2632 // during compilation to ensure correctness.
2633 // Take care that overlapping moves are preserved.
2634 // Restrict this optimization to the stack, to avoid duplicating loads from the heap;
2635 // see CL 145208 for discussion.
2636 (Move {t1} [s] dst tmp1 midmem:(Move {t2} [s] tmp2 src _))
2637 && t1.Compare(t2) == types.CMPeq
2638 && isSamePtr(tmp1, tmp2)
2639 && isStackPtr(src) && !isVolatile(src)
2640 && disjoint(src, s, tmp2, s)
2641 && (disjoint(src, s, dst, s) || isInlinableMemmove(dst, src, s, config))
2642 => (Move {t1} [s] dst src midmem)
2643
2644 // Same, but for large types that require VarDefs.
2645 (Move {t1} [s] dst tmp1 midmem:(VarDef (Move {t2} [s] tmp2 src _)))
2646 && t1.Compare(t2) == types.CMPeq
2647 && isSamePtr(tmp1, tmp2)
2648 && isStackPtr(src) && !isVolatile(src)
2649 && disjoint(src, s, tmp2, s)
2650 && (disjoint(src, s, dst, s) || isInlinableMemmove(dst, src, s, config))
2651 => (Move {t1} [s] dst src midmem)
2652
2653 // Don't zero the same bits twice.
2654 (Zero {t} [s] dst1 zero:(Zero {t} [s] dst2 _)) && isSamePtr(dst1, dst2) => zero
2655 (Zero {t} [s] dst1 vardef:(VarDef (Zero {t} [s] dst2 _))) && isSamePtr(dst1, dst2) => vardef
2656
2657 // Elide self-moves. This only happens rarely (e.g test/fixedbugs/bug277.go).
2658 // However, this rule is needed to prevent the previous rule from looping forever in such cases.
2659 (Move dst src mem) && isSamePtr(dst, src) => mem
2660
2661 // Constant rotate detection.
2662 ((Add64|Or64|Xor64) (Lsh64x64 x z:(Const64 <t> [c])) (Rsh64Ux64 x (Const64 [d]))) && c < 64 && d == 64-c && canRotate(config, 64) => (RotateLeft64 x z)
2663 ((Add32|Or32|Xor32) (Lsh32x64 x z:(Const64 <t> [c])) (Rsh32Ux64 x (Const64 [d]))) && c < 32 && d == 32-c && canRotate(config, 32) => (RotateLeft32 x z)
2664 ((Add16|Or16|Xor16) (Lsh16x64 x z:(Const64 <t> [c])) (Rsh16Ux64 x (Const64 [d]))) && c < 16 && d == 16-c && canRotate(config, 16) => (RotateLeft16 x z)
2665 ((Add8|Or8|Xor8) (Lsh8x64 x z:(Const64 <t> [c])) (Rsh8Ux64 x (Const64 [d]))) && c < 8 && d == 8-c && canRotate(config, 8) => (RotateLeft8 x z)
2666
2667 // Non-constant rotate detection.
2668 // We use shiftIsBounded to make sure that neither of the shifts are >64.
2669 // Note: these rules are subtle when the shift amounts are 0/64, as Go shifts
2670 // are different from most native shifts. But it works out.
2671 ((Add64|Or64|Xor64) left:(Lsh64x64 x y) right:(Rsh64Ux64 x (Sub64 (Const64 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2672 ((Add64|Or64|Xor64) left:(Lsh64x32 x y) right:(Rsh64Ux32 x (Sub32 (Const32 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2673 ((Add64|Or64|Xor64) left:(Lsh64x16 x y) right:(Rsh64Ux16 x (Sub16 (Const16 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2674 ((Add64|Or64|Xor64) left:(Lsh64x8 x y) right:(Rsh64Ux8 x (Sub8 (Const8 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x y)
2675
2676 ((Add64|Or64|Xor64) right:(Rsh64Ux64 x y) left:(Lsh64x64 x z:(Sub64 (Const64 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2677 ((Add64|Or64|Xor64) right:(Rsh64Ux32 x y) left:(Lsh64x32 x z:(Sub32 (Const32 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2678 ((Add64|Or64|Xor64) right:(Rsh64Ux16 x y) left:(Lsh64x16 x z:(Sub16 (Const16 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2679 ((Add64|Or64|Xor64) right:(Rsh64Ux8 x y) left:(Lsh64x8 x z:(Sub8 (Const8 [64]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 64) => (RotateLeft64 x z)
2680
2681 ((Add32|Or32|Xor32) left:(Lsh32x64 x y) right:(Rsh32Ux64 x (Sub64 (Const64 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2682 ((Add32|Or32|Xor32) left:(Lsh32x32 x y) right:(Rsh32Ux32 x (Sub32 (Const32 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2683 ((Add32|Or32|Xor32) left:(Lsh32x16 x y) right:(Rsh32Ux16 x (Sub16 (Const16 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2684 ((Add32|Or32|Xor32) left:(Lsh32x8 x y) right:(Rsh32Ux8 x (Sub8 (Const8 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x y)
2685
2686 ((Add32|Or32|Xor32) right:(Rsh32Ux64 x y) left:(Lsh32x64 x z:(Sub64 (Const64 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2687 ((Add32|Or32|Xor32) right:(Rsh32Ux32 x y) left:(Lsh32x32 x z:(Sub32 (Const32 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2688 ((Add32|Or32|Xor32) right:(Rsh32Ux16 x y) left:(Lsh32x16 x z:(Sub16 (Const16 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2689 ((Add32|Or32|Xor32) right:(Rsh32Ux8 x y) left:(Lsh32x8 x z:(Sub8 (Const8 [32]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 32) => (RotateLeft32 x z)
2690
2691 ((Add16|Or16|Xor16) left:(Lsh16x64 x y) right:(Rsh16Ux64 x (Sub64 (Const64 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2692 ((Add16|Or16|Xor16) left:(Lsh16x32 x y) right:(Rsh16Ux32 x (Sub32 (Const32 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2693 ((Add16|Or16|Xor16) left:(Lsh16x16 x y) right:(Rsh16Ux16 x (Sub16 (Const16 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2694 ((Add16|Or16|Xor16) left:(Lsh16x8 x y) right:(Rsh16Ux8 x (Sub8 (Const8 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x y)
2695
2696 ((Add16|Or16|Xor16) right:(Rsh16Ux64 x y) left:(Lsh16x64 x z:(Sub64 (Const64 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2697 ((Add16|Or16|Xor16) right:(Rsh16Ux32 x y) left:(Lsh16x32 x z:(Sub32 (Const32 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2698 ((Add16|Or16|Xor16) right:(Rsh16Ux16 x y) left:(Lsh16x16 x z:(Sub16 (Const16 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2699 ((Add16|Or16|Xor16) right:(Rsh16Ux8 x y) left:(Lsh16x8 x z:(Sub8 (Const8 [16]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 16) => (RotateLeft16 x z)
2700
2701 ((Add8|Or8|Xor8) left:(Lsh8x64 x y) right:(Rsh8Ux64 x (Sub64 (Const64 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2702 ((Add8|Or8|Xor8) left:(Lsh8x32 x y) right:(Rsh8Ux32 x (Sub32 (Const32 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2703 ((Add8|Or8|Xor8) left:(Lsh8x16 x y) right:(Rsh8Ux16 x (Sub16 (Const16 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2704 ((Add8|Or8|Xor8) left:(Lsh8x8 x y) right:(Rsh8Ux8 x (Sub8 (Const8 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x y)
2705
2706 ((Add8|Or8|Xor8) right:(Rsh8Ux64 x y) left:(Lsh8x64 x z:(Sub64 (Const64 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2707 ((Add8|Or8|Xor8) right:(Rsh8Ux32 x y) left:(Lsh8x32 x z:(Sub32 (Const32 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2708 ((Add8|Or8|Xor8) right:(Rsh8Ux16 x y) left:(Lsh8x16 x z:(Sub16 (Const16 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2709 ((Add8|Or8|Xor8) right:(Rsh8Ux8 x y) left:(Lsh8x8 x z:(Sub8 (Const8 [8]) y))) && (shiftIsBounded(left) || shiftIsBounded(right)) && canRotate(config, 8) => (RotateLeft8 x z)
2710
2711 // Rotating by y&c, with c a mask that doesn't change the bottom bits, is the same as rotating by y.
2712 (RotateLeft64 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&63 == 63 => (RotateLeft64 x y)
2713 (RotateLeft32 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&31 == 31 => (RotateLeft32 x y)
2714 (RotateLeft16 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&15 == 15 => (RotateLeft16 x y)
2715 (RotateLeft8 x (And(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&7 == 7 => (RotateLeft8 x y)
2716
2717 // Rotating by -(y&c), with c a mask that doesn't change the bottom bits, is the same as rotating by -y.
2718 (RotateLeft64 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&63 == 63 => (RotateLeft64 x (Neg(64|32|16|8) <y.Type> y))
2719 (RotateLeft32 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&31 == 31 => (RotateLeft32 x (Neg(64|32|16|8) <y.Type> y))
2720 (RotateLeft16 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&15 == 15 => (RotateLeft16 x (Neg(64|32|16|8) <y.Type> y))
2721 (RotateLeft8 x (Neg(64|32|16|8) (And(64|32|16|8) y (Const(64|32|16|8) [c])))) && c&7 == 7 => (RotateLeft8 x (Neg(64|32|16|8) <y.Type> y))
2722
2723 // Rotating by y+c, with c a multiple of the value width, is the same as rotating by y.
2724 (RotateLeft64 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&63 == 0 => (RotateLeft64 x y)
2725 (RotateLeft32 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&31 == 0 => (RotateLeft32 x y)
2726 (RotateLeft16 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&15 == 0 => (RotateLeft16 x y)
2727 (RotateLeft8 x (Add(64|32|16|8) y (Const(64|32|16|8) [c]))) && c&7 == 0 => (RotateLeft8 x y)
2728
2729 // Rotating by c-y, with c a multiple of the value width, is the same as rotating by -y.
2730 (RotateLeft64 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&63 == 0 => (RotateLeft64 x (Neg(64|32|16|8) <y.Type> y))
2731 (RotateLeft32 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&31 == 0 => (RotateLeft32 x (Neg(64|32|16|8) <y.Type> y))
2732 (RotateLeft16 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&15 == 0 => (RotateLeft16 x (Neg(64|32|16|8) <y.Type> y))
2733 (RotateLeft8 x (Sub(64|32|16|8) (Const(64|32|16|8) [c]) y)) && c&7 == 0 => (RotateLeft8 x (Neg(64|32|16|8) <y.Type> y))
2734
2735 // Ensure we don't do Const64 rotates in a 32-bit system.
2736 (RotateLeft64 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft64 x (Const32 <t> [int32(c)]))
2737 (RotateLeft32 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft32 x (Const32 <t> [int32(c)]))
2738 (RotateLeft16 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft16 x (Const32 <t> [int32(c)]))
2739 (RotateLeft8 x (Const64 <t> [c])) && config.PtrSize == 4 => (RotateLeft8 x (Const32 <t> [int32(c)]))
2740
2741 // Rotating by c, then by d, is the same as rotating by c+d.
2742 // We're trading a rotate for an add, which seems generally a good choice. It is especially good when c and d are constants.
2743 // This rule is a bit tricky as c and d might be different widths. We handle only cases where they are the same width.
2744 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 8 && d.Type.Size() == 8 => (RotateLeft(64|32|16|8) x (Add64 <c.Type> c d))
2745 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 4 && d.Type.Size() == 4 => (RotateLeft(64|32|16|8) x (Add32 <c.Type> c d))
2746 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 2 && d.Type.Size() == 2 => (RotateLeft(64|32|16|8) x (Add16 <c.Type> c d))
2747 (RotateLeft(64|32|16|8) (RotateLeft(64|32|16|8) x c) d) && c.Type.Size() == 1 && d.Type.Size() == 1 => (RotateLeft(64|32|16|8) x (Add8 <c.Type> c d))
2748
2749 // Loading constant values from dictionaries and itabs.
2750 (Load <t> (OffPtr [off] (Addr {s} sb) ) _) && t.IsUintptr() && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2751 (Load <t> (OffPtr [off] (Convert (Addr {s} sb) _) ) _) && t.IsUintptr() && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2752 (Load <t> (OffPtr [off] (ITab (IMake (Addr {s} sb) _))) _) && t.IsUintptr() && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2753 (Load <t> (OffPtr [off] (ITab (IMake (Convert (Addr {s} sb) _) _))) _) && t.IsUintptr() && isFixedSym(s, off) => (Addr {fixedSym(b.Func, s, off)} sb)
2754
2755 // Loading constant values from runtime._type.hash.
2756 (Load <t> (OffPtr [off] (Addr {sym} _) ) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2757 (Load <t> (OffPtr [off] (Convert (Addr {sym} _) _) ) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2758 (Load <t> (OffPtr [off] (ITab (IMake (Addr {sym} _) _))) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2759 (Load <t> (OffPtr [off] (ITab (IMake (Convert (Addr {sym} _) _) _))) _) && t.IsInteger() && t.Size() == 4 && isFixed32(config, sym, off) => (Const32 [fixed32(config, sym, off)])
2760
2761 // Calling cmpstring a second time with the same arguments in the
2762 // same memory state can reuse the results of the first call.
2763 // See issue 61725.
2764 // Note that this could pretty easily generalize to any pure function.
2765 (SelectN [0] (StaticLECall {f} x y (SelectN [1] c:(StaticLECall {g} x y mem))))
2766 && isSameCall(f, "runtime.cmpstring")
2767 && isSameCall(g, "runtime.cmpstring")
2768 => @c.Block (SelectN [0] <typ.Int> c)
2769
2770 // If we don't use the result of cmpstring, might as well not call it.
2771 // Note that this could pretty easily generalize to any pure function.
2772 (SelectN [1] c:(StaticLECall {f} _ _ mem)) && c.Uses == 1 && isSameCall(f, "runtime.cmpstring") && clobber(c) => mem
2773
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