Source file src/runtime/runtime1.go

     1  // Copyright 2009 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  package runtime
     6  
     7  import (
     8  	"internal/bytealg"
     9  	"internal/goarch"
    10  	"internal/runtime/atomic"
    11  	"internal/strconv"
    12  	"unsafe"
    13  )
    14  
    15  // Keep a cached value to make gotraceback fast,
    16  // since we call it on every call to gentraceback.
    17  // The cached value is a uint32 in which the low bits
    18  // are the "crash" and "all" settings and the remaining
    19  // bits are the traceback value (0 off, 1 on, 2 include system).
    20  const (
    21  	tracebackCrash = 1 << iota
    22  	tracebackAll
    23  	tracebackShift = iota
    24  )
    25  
    26  var traceback_cache uint32 = 2 << tracebackShift
    27  var traceback_env uint32
    28  
    29  // gotraceback returns the current traceback settings.
    30  //
    31  // If level is 0, suppress all tracebacks.
    32  // If level is 1, show tracebacks, but exclude runtime frames.
    33  // If level is 2, show tracebacks including runtime frames.
    34  // If all is set, print all goroutine stacks. Otherwise, print just the current goroutine.
    35  // If crash is set, crash (core dump, etc) after tracebacking.
    36  //
    37  //go:nosplit
    38  func gotraceback() (level int32, all, crash bool) {
    39  	gp := getg()
    40  	t := atomic.Load(&traceback_cache)
    41  	crash = t&tracebackCrash != 0
    42  	all = gp.m.throwing > throwTypeUser || t&tracebackAll != 0
    43  	if gp.m.traceback != 0 {
    44  		level = int32(gp.m.traceback)
    45  	} else if gp.m.throwing >= throwTypeRuntime {
    46  		// Always include runtime frames in runtime throws unless
    47  		// otherwise overridden by m.traceback.
    48  		level = 2
    49  	} else {
    50  		level = int32(t >> tracebackShift)
    51  	}
    52  	return
    53  }
    54  
    55  var (
    56  	argc int32
    57  	argv **byte
    58  )
    59  
    60  // nosplit for use in linux startup sysargs.
    61  //
    62  //go:nosplit
    63  func argv_index(argv **byte, i int32) *byte {
    64  	return *(**byte)(add(unsafe.Pointer(argv), uintptr(i)*goarch.PtrSize))
    65  }
    66  
    67  func args(c int32, v **byte) {
    68  	argc = c
    69  	argv = v
    70  	sysargs(c, v)
    71  }
    72  
    73  func goargs() {
    74  	if GOOS == "windows" {
    75  		return
    76  	}
    77  	argslice = make([]string, argc)
    78  	for i := int32(0); i < argc; i++ {
    79  		argslice[i] = gostringnocopy(argv_index(argv, i))
    80  	}
    81  }
    82  
    83  func goenvs_unix() {
    84  	// TODO(austin): ppc64 in dynamic linking mode doesn't
    85  	// guarantee env[] will immediately follow argv. Might cause
    86  	// problems.
    87  	n := int32(0)
    88  	for argv_index(argv, argc+1+n) != nil {
    89  		n++
    90  	}
    91  
    92  	envs = make([]string, n)
    93  	for i := int32(0); i < n; i++ {
    94  		envs[i] = gostring(argv_index(argv, argc+1+i))
    95  	}
    96  }
    97  
    98  func environ() []string {
    99  	return envs
   100  }
   101  
   102  // TODO: These should be locals in testAtomic64, but we don't 8-byte
   103  // align stack variables on 386.
   104  var test_z64, test_x64 uint64
   105  
   106  func testAtomic64() {
   107  	test_z64 = 42
   108  	test_x64 = 0
   109  	if atomic.Cas64(&test_z64, test_x64, 1) {
   110  		throw("cas64 failed")
   111  	}
   112  	if test_x64 != 0 {
   113  		throw("cas64 failed")
   114  	}
   115  	test_x64 = 42
   116  	if !atomic.Cas64(&test_z64, test_x64, 1) {
   117  		throw("cas64 failed")
   118  	}
   119  	if test_x64 != 42 || test_z64 != 1 {
   120  		throw("cas64 failed")
   121  	}
   122  	if atomic.Load64(&test_z64) != 1 {
   123  		throw("load64 failed")
   124  	}
   125  	atomic.Store64(&test_z64, (1<<40)+1)
   126  	if atomic.Load64(&test_z64) != (1<<40)+1 {
   127  		throw("store64 failed")
   128  	}
   129  	if atomic.Xadd64(&test_z64, (1<<40)+1) != (2<<40)+2 {
   130  		throw("xadd64 failed")
   131  	}
   132  	if atomic.Load64(&test_z64) != (2<<40)+2 {
   133  		throw("xadd64 failed")
   134  	}
   135  	if atomic.Xchg64(&test_z64, (3<<40)+3) != (2<<40)+2 {
   136  		throw("xchg64 failed")
   137  	}
   138  	if atomic.Load64(&test_z64) != (3<<40)+3 {
   139  		throw("xchg64 failed")
   140  	}
   141  }
   142  
   143  func check() {
   144  	var (
   145  		a     int8
   146  		b     uint8
   147  		c     int16
   148  		d     uint16
   149  		e     int32
   150  		f     uint32
   151  		g     int64
   152  		h     uint64
   153  		i, i1 float32
   154  		j, j1 float64
   155  		k     unsafe.Pointer
   156  		l     *uint16
   157  		m     [4]byte
   158  	)
   159  	type x1t struct {
   160  		x uint8
   161  	}
   162  	type y1t struct {
   163  		x1 x1t
   164  		y  uint8
   165  	}
   166  	var x1 x1t
   167  	var y1 y1t
   168  
   169  	if unsafe.Sizeof(a) != 1 {
   170  		throw("bad a")
   171  	}
   172  	if unsafe.Sizeof(b) != 1 {
   173  		throw("bad b")
   174  	}
   175  	if unsafe.Sizeof(c) != 2 {
   176  		throw("bad c")
   177  	}
   178  	if unsafe.Sizeof(d) != 2 {
   179  		throw("bad d")
   180  	}
   181  	if unsafe.Sizeof(e) != 4 {
   182  		throw("bad e")
   183  	}
   184  	if unsafe.Sizeof(f) != 4 {
   185  		throw("bad f")
   186  	}
   187  	if unsafe.Sizeof(g) != 8 {
   188  		throw("bad g")
   189  	}
   190  	if unsafe.Sizeof(h) != 8 {
   191  		throw("bad h")
   192  	}
   193  	if unsafe.Sizeof(i) != 4 {
   194  		throw("bad i")
   195  	}
   196  	if unsafe.Sizeof(j) != 8 {
   197  		throw("bad j")
   198  	}
   199  	if unsafe.Sizeof(k) != goarch.PtrSize {
   200  		throw("bad k")
   201  	}
   202  	if unsafe.Sizeof(l) != goarch.PtrSize {
   203  		throw("bad l")
   204  	}
   205  	if unsafe.Sizeof(x1) != 1 {
   206  		throw("bad unsafe.Sizeof x1")
   207  	}
   208  	if unsafe.Offsetof(y1.y) != 1 {
   209  		throw("bad offsetof y1.y")
   210  	}
   211  	if unsafe.Sizeof(y1) != 2 {
   212  		throw("bad unsafe.Sizeof y1")
   213  	}
   214  
   215  	var z uint32
   216  	z = 1
   217  	if !atomic.Cas(&z, 1, 2) {
   218  		throw("cas1")
   219  	}
   220  	if z != 2 {
   221  		throw("cas2")
   222  	}
   223  
   224  	z = 4
   225  	if atomic.Cas(&z, 5, 6) {
   226  		throw("cas3")
   227  	}
   228  	if z != 4 {
   229  		throw("cas4")
   230  	}
   231  
   232  	z = 0xffffffff
   233  	if !atomic.Cas(&z, 0xffffffff, 0xfffffffe) {
   234  		throw("cas5")
   235  	}
   236  	if z != 0xfffffffe {
   237  		throw("cas6")
   238  	}
   239  
   240  	m = [4]byte{1, 1, 1, 1}
   241  	atomic.Or8(&m[1], 0xf0)
   242  	if m[0] != 1 || m[1] != 0xf1 || m[2] != 1 || m[3] != 1 {
   243  		throw("atomicor8")
   244  	}
   245  
   246  	m = [4]byte{0xff, 0xff, 0xff, 0xff}
   247  	atomic.And8(&m[1], 0x1)
   248  	if m[0] != 0xff || m[1] != 0x1 || m[2] != 0xff || m[3] != 0xff {
   249  		throw("atomicand8")
   250  	}
   251  
   252  	*(*uint64)(unsafe.Pointer(&j)) = ^uint64(0)
   253  	if j == j {
   254  		throw("float64nan")
   255  	}
   256  	if !(j != j) {
   257  		throw("float64nan1")
   258  	}
   259  
   260  	*(*uint64)(unsafe.Pointer(&j1)) = ^uint64(1)
   261  	if j == j1 {
   262  		throw("float64nan2")
   263  	}
   264  	if !(j != j1) {
   265  		throw("float64nan3")
   266  	}
   267  
   268  	*(*uint32)(unsafe.Pointer(&i)) = ^uint32(0)
   269  	if i == i {
   270  		throw("float32nan")
   271  	}
   272  	if i == i {
   273  		throw("float32nan1")
   274  	}
   275  
   276  	*(*uint32)(unsafe.Pointer(&i1)) = ^uint32(1)
   277  	if i == i1 {
   278  		throw("float32nan2")
   279  	}
   280  	if i == i1 {
   281  		throw("float32nan3")
   282  	}
   283  
   284  	testAtomic64()
   285  
   286  	if fixedStack != round2(fixedStack) {
   287  		throw("FixedStack is not power-of-2")
   288  	}
   289  
   290  	if !checkASM() {
   291  		throw("assembly checks failed")
   292  	}
   293  }
   294  
   295  type dbgVar struct {
   296  	name   string
   297  	value  *int32        // for variables that can only be set at startup
   298  	atomic *atomic.Int32 // for variables that can be changed during execution
   299  	def    int32         // default value (ideally zero)
   300  }
   301  
   302  // Holds variables parsed from GODEBUG env var,
   303  // except for "memprofilerate" since there is an
   304  // existing int var for that value, which may
   305  // already have an initial value.
   306  var debug struct {
   307  	cgocheck                 int32
   308  	clobberfree              int32
   309  	containermaxprocs        int32
   310  	decoratemappings         int32
   311  	disablethp               int32
   312  	dontfreezetheworld       int32
   313  	efence                   int32
   314  	gccheckmark              int32
   315  	gcpacertrace             int32
   316  	gcshrinkstackoff         int32
   317  	gcstoptheworld           int32
   318  	gctrace                  int32
   319  	invalidptr               int32
   320  	madvdontneed             int32 // for Linux; issue 28466
   321  	scavtrace                int32
   322  	scheddetail              int32
   323  	schedtrace               int32
   324  	tracebackancestors       int32
   325  	updatemaxprocs           int32
   326  	asyncpreemptoff          int32
   327  	harddecommit             int32
   328  	adaptivestackstart       int32
   329  	tracefpunwindoff         int32
   330  	traceadvanceperiod       int32
   331  	traceCheckStackOwnership int32
   332  	profstackdepth           int32
   333  	dataindependenttiming    int32
   334  
   335  	// debug.malloc is used as a combined debug check
   336  	// in the malloc function and should be set
   337  	// if any of the below debug options is != 0.
   338  	malloc          bool
   339  	inittrace       int32
   340  	sbrk            int32
   341  	checkfinalizers int32
   342  	// traceallocfree controls whether execution traces contain
   343  	// detailed trace data about memory allocation. This value
   344  	// affects debug.malloc only if it is != 0 and the execution
   345  	// tracer is enabled, in which case debug.malloc will be
   346  	// set to "true" if it isn't already while tracing is enabled.
   347  	// It will be set while the world is stopped, so it's safe.
   348  	// The value of traceallocfree can be changed any time in response
   349  	// to os.Setenv("GODEBUG").
   350  	traceallocfree atomic.Int32
   351  
   352  	panicnil atomic.Int32
   353  
   354  	// asynctimerchan controls whether timer channels
   355  	// behave asynchronously (as in Go 1.22 and earlier)
   356  	// instead of their Go 1.23+ synchronous behavior.
   357  	// The value can change at any time (in response to os.Setenv("GODEBUG"))
   358  	// and affects all extant timer channels immediately.
   359  	// Programs wouldn't normally change over an execution,
   360  	// but allowing it is convenient for testing and for programs
   361  	// that do an os.Setenv in main.init or main.main.
   362  	asynctimerchan atomic.Int32
   363  
   364  	// tracebacklabels controls the inclusion of goroutine labels in the
   365  	// goroutine status header line.
   366  	tracebacklabels atomic.Int32
   367  }
   368  
   369  var dbgvars = []*dbgVar{
   370  	{name: "adaptivestackstart", value: &debug.adaptivestackstart},
   371  	{name: "asyncpreemptoff", value: &debug.asyncpreemptoff},
   372  	{name: "asynctimerchan", atomic: &debug.asynctimerchan},
   373  	{name: "cgocheck", value: &debug.cgocheck},
   374  	{name: "clobberfree", value: &debug.clobberfree},
   375  	{name: "containermaxprocs", value: &debug.containermaxprocs, def: 1},
   376  	{name: "dataindependenttiming", value: &debug.dataindependenttiming},
   377  	{name: "decoratemappings", value: &debug.decoratemappings, def: 1},
   378  	{name: "disablethp", value: &debug.disablethp},
   379  	{name: "dontfreezetheworld", value: &debug.dontfreezetheworld},
   380  	{name: "checkfinalizers", value: &debug.checkfinalizers},
   381  	{name: "efence", value: &debug.efence},
   382  	{name: "gccheckmark", value: &debug.gccheckmark},
   383  	{name: "gcpacertrace", value: &debug.gcpacertrace},
   384  	{name: "gcshrinkstackoff", value: &debug.gcshrinkstackoff},
   385  	{name: "gcstoptheworld", value: &debug.gcstoptheworld},
   386  	{name: "gctrace", value: &debug.gctrace},
   387  	{name: "harddecommit", value: &debug.harddecommit},
   388  	{name: "inittrace", value: &debug.inittrace},
   389  	{name: "invalidptr", value: &debug.invalidptr},
   390  	{name: "madvdontneed", value: &debug.madvdontneed},
   391  	{name: "panicnil", atomic: &debug.panicnil},
   392  	{name: "profstackdepth", value: &debug.profstackdepth, def: 128},
   393  	{name: "sbrk", value: &debug.sbrk},
   394  	{name: "scavtrace", value: &debug.scavtrace},
   395  	{name: "scheddetail", value: &debug.scheddetail},
   396  	{name: "schedtrace", value: &debug.schedtrace},
   397  	{name: "traceadvanceperiod", value: &debug.traceadvanceperiod},
   398  	{name: "traceallocfree", atomic: &debug.traceallocfree},
   399  	{name: "tracecheckstackownership", value: &debug.traceCheckStackOwnership},
   400  	{name: "tracebackancestors", value: &debug.tracebackancestors},
   401  	{name: "tracebacklabels", atomic: &debug.tracebacklabels, def: 0},
   402  	{name: "tracefpunwindoff", value: &debug.tracefpunwindoff},
   403  	{name: "updatemaxprocs", value: &debug.updatemaxprocs, def: 1},
   404  }
   405  
   406  func parseRuntimeDebugVars(godebug string) {
   407  	// defaults
   408  	debug.cgocheck = 1
   409  	debug.invalidptr = 1
   410  	debug.adaptivestackstart = 1 // set this to 0 to turn larger initial goroutine stacks off
   411  	if GOOS == "linux" {
   412  		// On Linux, MADV_FREE is faster than MADV_DONTNEED,
   413  		// but doesn't affect many of the statistics that
   414  		// MADV_DONTNEED does until the memory is actually
   415  		// reclaimed. This generally leads to poor user
   416  		// experience, like confusing stats in top and other
   417  		// monitoring tools; and bad integration with
   418  		// management systems that respond to memory usage.
   419  		// Hence, default to MADV_DONTNEED.
   420  		debug.madvdontneed = 1
   421  	}
   422  	debug.traceadvanceperiod = defaultTraceAdvancePeriod
   423  
   424  	// apply runtime defaults, if any
   425  	for _, v := range dbgvars {
   426  		if v.def != 0 {
   427  			// Every var should have either v.value or v.atomic set.
   428  			if v.value != nil {
   429  				*v.value = v.def
   430  			} else if v.atomic != nil {
   431  				v.atomic.Store(v.def)
   432  			}
   433  		}
   434  	}
   435  	// apply compile-time GODEBUG settings
   436  	parsegodebug(godebugDefault, nil)
   437  
   438  	// apply environment settings
   439  	parsegodebug(godebug, nil)
   440  
   441  	debug.malloc = (debug.inittrace | debug.sbrk | debug.checkfinalizers) != 0
   442  	debug.profstackdepth = min(debug.profstackdepth, maxProfStackDepth)
   443  
   444  	// Disable async preemption in checkmark mode. The following situation is
   445  	// problematic with checkmark mode:
   446  	//
   447  	// - The GC doesn't mark object A because it is truly dead.
   448  	// - The GC stops the world, asynchronously preempting G1 which has a reference
   449  	//   to A in its top stack frame
   450  	// - During the stop the world, we run the second checkmark GC. It marks the roots
   451  	//   and discovers A through G1.
   452  	// - Checkmark mode reports a failure since there's a discrepancy in mark metadata.
   453  	//
   454  	// We could disable just conservative scanning during the checkmark scan, which is
   455  	// safe but makes checkmark slightly less powerful, but that's a lot more invasive
   456  	// than just disabling async preemption altogether.
   457  	if debug.gccheckmark > 0 {
   458  		debug.asyncpreemptoff = 1
   459  	}
   460  }
   461  
   462  func finishDebugVarsSetup() {
   463  	p := new(string)
   464  	*p = gogetenv("GODEBUG")
   465  	godebugEnv.Store(p)
   466  
   467  	setTraceback(gogetenv("GOTRACEBACK"))
   468  	traceback_env = traceback_cache
   469  }
   470  
   471  // reparsedebugvars reparses the runtime's debug variables
   472  // because the environment variable has been changed to env.
   473  func reparsedebugvars(env string) {
   474  	seen := make(map[string]bool)
   475  	// apply environment settings
   476  	parsegodebug(env, seen)
   477  	// apply compile-time GODEBUG settings for as-yet-unseen variables
   478  	parsegodebug(godebugDefault, seen)
   479  	// apply defaults for as-yet-unseen variables
   480  	for _, v := range dbgvars {
   481  		if v.atomic != nil && !seen[v.name] {
   482  			v.atomic.Store(0)
   483  		}
   484  	}
   485  }
   486  
   487  // parsegodebug parses the godebug string, updating variables listed in dbgvars.
   488  // If seen == nil, this is startup time and we process the string left to right
   489  // overwriting older settings with newer ones.
   490  // If seen != nil, $GODEBUG has changed and we are doing an
   491  // incremental update. To avoid flapping in the case where a value is
   492  // set multiple times (perhaps in the default and the environment,
   493  // or perhaps twice in the environment), we process the string right-to-left
   494  // and only change values not already seen. After doing this for both
   495  // the environment and the default settings, the caller must also call
   496  // cleargodebug(seen) to reset any now-unset values back to their defaults.
   497  func parsegodebug(godebug string, seen map[string]bool) {
   498  	for p := godebug; p != ""; {
   499  		var field string
   500  		if seen == nil {
   501  			// startup: process left to right, overwriting older settings with newer
   502  			i := bytealg.IndexByteString(p, ',')
   503  			if i < 0 {
   504  				field, p = p, ""
   505  			} else {
   506  				field, p = p[:i], p[i+1:]
   507  			}
   508  		} else {
   509  			// incremental update: process right to left, updating and skipping seen
   510  			i := len(p) - 1
   511  			for i >= 0 && p[i] != ',' {
   512  				i--
   513  			}
   514  			if i < 0 {
   515  				p, field = "", p
   516  			} else {
   517  				p, field = p[:i], p[i+1:]
   518  			}
   519  		}
   520  		i := bytealg.IndexByteString(field, '=')
   521  		if i < 0 {
   522  			continue
   523  		}
   524  		key, value := field[:i], field[i+1:]
   525  		if seen[key] {
   526  			continue
   527  		}
   528  		if seen != nil {
   529  			seen[key] = true
   530  		}
   531  
   532  		// Update MemProfileRate directly here since it
   533  		// is int, not int32, and should only be updated
   534  		// if specified in GODEBUG.
   535  		if seen == nil && key == "memprofilerate" {
   536  			if n, err := strconv.Atoi(value); err == nil {
   537  				MemProfileRate = n
   538  			}
   539  		} else {
   540  			for _, v := range dbgvars {
   541  				if v.name == key {
   542  					if n, err := strconv.ParseInt(value, 10, 32); err == nil {
   543  						if seen == nil && v.value != nil {
   544  							*v.value = int32(n)
   545  						} else if v.atomic != nil {
   546  							v.atomic.Store(int32(n))
   547  						}
   548  					}
   549  				}
   550  			}
   551  		}
   552  	}
   553  
   554  	if debug.cgocheck > 1 {
   555  		throw("cgocheck > 1 mode is no longer supported at runtime. Use GOEXPERIMENT=cgocheck2 at build time instead.")
   556  	}
   557  }
   558  
   559  //go:linkname setTraceback runtime/debug.SetTraceback
   560  func setTraceback(level string) {
   561  	var t uint32
   562  	switch level {
   563  	case "none":
   564  		t = 0
   565  	case "single", "":
   566  		t = 1 << tracebackShift
   567  	case "all":
   568  		t = 1<<tracebackShift | tracebackAll
   569  	case "system":
   570  		t = 2<<tracebackShift | tracebackAll
   571  	case "crash":
   572  		t = 2<<tracebackShift | tracebackAll | tracebackCrash
   573  	case "wer":
   574  		if GOOS == "windows" {
   575  			t = 2<<tracebackShift | tracebackAll | tracebackCrash
   576  			enableWER()
   577  			break
   578  		}
   579  		fallthrough
   580  	default:
   581  		t = tracebackAll
   582  		if n, err := strconv.Atoi(level); err == nil && n == int(uint32(n)) {
   583  			t |= uint32(n) << tracebackShift
   584  		}
   585  	}
   586  	// when C owns the process, simply exit'ing the process on fatal errors
   587  	// and panics is surprising. Be louder and abort instead.
   588  	if islibrary || isarchive {
   589  		t |= tracebackCrash
   590  	}
   591  
   592  	t |= traceback_env
   593  
   594  	atomic.Store(&traceback_cache, t)
   595  }
   596  
   597  // Helpers for Go. Must be NOSPLIT, must only call NOSPLIT functions, and must not block.
   598  
   599  //go:nosplit
   600  func acquirem() *m {
   601  	gp := getg()
   602  	gp.m.locks++
   603  	return gp.m
   604  }
   605  
   606  //go:nosplit
   607  func releasem(mp *m) {
   608  	gp := getg()
   609  	mp.locks--
   610  	if mp.locks == 0 && gp.preempt {
   611  		// restore the preemption request in case we've cleared it in newstack
   612  		gp.stackguard0 = stackPreempt
   613  	}
   614  }
   615  
   616  // reflect_typelinks is meant for package reflect,
   617  // but widely used packages access it using linkname.
   618  // Notable members of the hall of shame include:
   619  //   - gitee.com/quant1x/gox
   620  //   - github.com/goccy/json
   621  //   - github.com/modern-go/reflect2
   622  //   - github.com/vmware/govmomi
   623  //   - github.com/pinpoint-apm/pinpoint-go-agent
   624  //   - github.com/timandy/routine
   625  //   - github.com/v2pro/plz
   626  //
   627  // Do not remove or change the type signature.
   628  // See go.dev/issue/67401.
   629  //
   630  //go:linkname reflect_typelinks reflect.typelinks
   631  func reflect_typelinks() ([]unsafe.Pointer, [][]int32) {
   632  	modules := activeModules()
   633  	sections := []unsafe.Pointer{unsafe.Pointer(modules[0].types)}
   634  	ret := [][]int32{modules[0].typelinks}
   635  	for _, md := range modules[1:] {
   636  		sections = append(sections, unsafe.Pointer(md.types))
   637  		ret = append(ret, md.typelinks)
   638  	}
   639  	return sections, ret
   640  }
   641  
   642  // reflect_resolveNameOff resolves a name offset from a base pointer.
   643  //
   644  // reflect_resolveNameOff is for package reflect,
   645  // but widely used packages access it using linkname.
   646  // Notable members of the hall of shame include:
   647  //   - github.com/agiledragon/gomonkey/v2
   648  //
   649  // Do not remove or change the type signature.
   650  // See go.dev/issue/67401.
   651  //
   652  //go:linkname reflect_resolveNameOff reflect.resolveNameOff
   653  func reflect_resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer {
   654  	return unsafe.Pointer(resolveNameOff(ptrInModule, nameOff(off)).Bytes)
   655  }
   656  
   657  // reflect_resolveTypeOff resolves an *rtype offset from a base type.
   658  //
   659  // reflect_resolveTypeOff is meant for package reflect,
   660  // but widely used packages access it using linkname.
   661  // Notable members of the hall of shame include:
   662  //   - gitee.com/quant1x/gox
   663  //   - github.com/modern-go/reflect2
   664  //   - github.com/v2pro/plz
   665  //   - github.com/timandy/routine
   666  //
   667  // Do not remove or change the type signature.
   668  // See go.dev/issue/67401.
   669  //
   670  //go:linkname reflect_resolveTypeOff reflect.resolveTypeOff
   671  func reflect_resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
   672  	return unsafe.Pointer(toRType((*_type)(rtype)).typeOff(typeOff(off)))
   673  }
   674  
   675  // reflect_resolveTextOff resolves a function pointer offset from a base type.
   676  //
   677  // reflect_resolveTextOff is for package reflect,
   678  // but widely used packages access it using linkname.
   679  // Notable members of the hall of shame include:
   680  //   - github.com/agiledragon/gomonkey/v2
   681  //
   682  // Do not remove or change the type signature.
   683  // See go.dev/issue/67401.
   684  //
   685  //go:linkname reflect_resolveTextOff reflect.resolveTextOff
   686  func reflect_resolveTextOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
   687  	return toRType((*_type)(rtype)).textOff(textOff(off))
   688  }
   689  
   690  // reflectlite_resolveNameOff resolves a name offset from a base pointer.
   691  //
   692  //go:linkname reflectlite_resolveNameOff internal/reflectlite.resolveNameOff
   693  func reflectlite_resolveNameOff(ptrInModule unsafe.Pointer, off int32) unsafe.Pointer {
   694  	return unsafe.Pointer(resolveNameOff(ptrInModule, nameOff(off)).Bytes)
   695  }
   696  
   697  // reflectlite_resolveTypeOff resolves an *rtype offset from a base type.
   698  //
   699  //go:linkname reflectlite_resolveTypeOff internal/reflectlite.resolveTypeOff
   700  func reflectlite_resolveTypeOff(rtype unsafe.Pointer, off int32) unsafe.Pointer {
   701  	return unsafe.Pointer(toRType((*_type)(rtype)).typeOff(typeOff(off)))
   702  }
   703  
   704  // reflect_addReflectOff adds a pointer to the reflection offset lookup map.
   705  //
   706  //go:linkname reflect_addReflectOff reflect.addReflectOff
   707  func reflect_addReflectOff(ptr unsafe.Pointer) int32 {
   708  	reflectOffsLock()
   709  	if reflectOffs.m == nil {
   710  		reflectOffs.m = make(map[int32]unsafe.Pointer)
   711  		reflectOffs.minv = make(map[unsafe.Pointer]int32)
   712  		reflectOffs.next = -1
   713  	}
   714  	id, found := reflectOffs.minv[ptr]
   715  	if !found {
   716  		id = reflectOffs.next
   717  		reflectOffs.next-- // use negative offsets as IDs to aid debugging
   718  		reflectOffs.m[id] = ptr
   719  		reflectOffs.minv[ptr] = id
   720  	}
   721  	reflectOffsUnlock()
   722  	return id
   723  }
   724  
   725  //go:linkname fips_getIndicator crypto/internal/fips140.getIndicator
   726  func fips_getIndicator() uint8 {
   727  	return getg().fipsIndicator
   728  }
   729  
   730  //go:linkname fips_setIndicator crypto/internal/fips140.setIndicator
   731  func fips_setIndicator(indicator uint8) {
   732  	getg().fipsIndicator = indicator
   733  }
   734  

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