[dev.regabi] cmd/compile: finish cleanup of Flag initialization

Now that all flags are in a struct, use struct tags to set the usage messages
and use reflection to walk the struct and register all the flags.

Also move some flag usage back into main.go that shouldn't
come with the rest of flag.go into package base.

Change-Id: Ie655582194906c9ab425c3d01ad8c304bc49bfe0
Reviewed-on: https://go-review.googlesource.com/c/go/+/271668
Trust: Russ Cox <rsc@golang.org>
Run-TryBot: Russ Cox <rsc@golang.org>
TryBot-Result: Go Bot <gobot@golang.org>
Reviewed-by: Matthew Dempsky <mdempsky@google.com>
This commit is contained in:
Russ Cox 2020-11-16 01:15:33 -05:00
parent 259fd8adbb
commit 756661c82a
3 changed files with 292 additions and 219 deletions

View file

@ -168,6 +168,7 @@ var knownFormats = map[string]string{
"map[int64]uint32 %v": "",
"math/big.Accuracy %s": "",
"reflect.Type %s": "",
"reflect.Type %v": "",
"rune %#U": "",
"rune %c": "",
"rune %q": "",

View file

@ -11,15 +11,12 @@ import (
"io/ioutil"
"log"
"os"
"reflect"
"runtime"
"strconv"
"strings"
"cmd/compile/internal/logopt"
"cmd/compile/internal/ssa"
"cmd/compile/internal/types"
"cmd/internal/dwarf"
"cmd/internal/obj"
"cmd/internal/objabi"
"cmd/internal/sys"
)
@ -30,195 +27,153 @@ func usage() {
Exit(2)
}
var Flag Flags
// Flag holds the parsed command-line flags.
// See ParseFlag for non-zero defaults.
var Flag CmdFlags
// gc debug flags
type Flags struct {
Percent, B, C, E,
K, L, N, S,
W, LowerE, LowerH, LowerJ,
LowerL, LowerM, LowerR, LowerW int
CompilingRuntime bool
Std bool
D string
AsmHdr string
BuildID string
LowerC int
Complete bool
LowerD string
Dwarf bool
GenDwarfInl int
InstallSuffix string
Lang string
LinkObj string
Live int
MSan bool
NoLocalImports bool
LowerO string
Pack bool
Race bool
Spectre string
LowerT bool
TrimPath string
WB bool
Shared bool
Dynlink bool
GoVersion string
SymABIs string
CPUProfile string
MemProfile string
TraceProfile string
BlockProfile string
MutexProfile string
Bench string
SmallFrames bool
JSON string
// A CountFlag is a counting integer flag.
// It accepts -name=value to set the value directly,
// but it also accepts -name with no =value to increment the count.
type CountFlag int
// CmdFlags defines the command-line flags (see var Flag).
// Each struct field is a different flag, by default named for the lower-case of the field name.
// If the flag name is a single letter, the default flag name is left upper-case.
// If the flag name is "Lower" followed by a single letter, the default flag name is the lower-case of the last letter.
//
// If this default flag name can't be made right, the `flag` struct tag can be used to replace it,
// but this should be done only in exceptional circumstances: it helps everyone if the flag name
// is obvious from the field name when the flag is used elsewhere in the compiler sources.
// The `flag:"-"` struct tag makes a field invisible to the flag logic and should also be used sparingly.
//
// Each field must have a `help` struct tag giving the flag help message.
//
// The allowed field types are bool, int, string, pointers to those (for values stored elsewhere),
// CountFlag (for a counting flag), and func(string) (for a flag that uses special code for parsing).
type CmdFlags struct {
// Single letters
B CountFlag "help:\"disable bounds checking\""
C CountFlag "help:\"disable printing of columns in error messages\""
D string "help:\"set relative `path` for local imports\""
E CountFlag "help:\"debug symbol export\""
I func(string) "help:\"add `directory` to import search path\""
K CountFlag "help:\"debug missing line numbers\""
L CountFlag "help:\"show full file names in error messages\""
N CountFlag "help:\"disable optimizations\""
S CountFlag "help:\"print assembly listing\""
// V is added by objabi.AddVersionFlag
W CountFlag "help:\"debug parse tree after type checking\""
LowerC int "help:\"concurrency during compilation (1 means no concurrency)\""
LowerD string "help:\"enable debugging settings; try -d help\""
LowerE CountFlag "help:\"no limit on number of errors reported\""
LowerH CountFlag "help:\"halt on error\""
LowerJ CountFlag "help:\"debug runtime-initialized variables\""
LowerL CountFlag "help:\"disable inlining\""
LowerM CountFlag "help:\"print optimization decisions\""
LowerO string "help:\"write output to `file`\""
LowerP *string "help:\"set expected package import `path`\"" // &Ctxt.Pkgpath, set below
LowerR CountFlag "help:\"debug generated wrappers\""
LowerT bool "help:\"enable tracing for debugging the compiler\""
LowerW CountFlag "help:\"debug type checking\""
LowerV *bool "help:\"increase debug verbosity\""
// Special characters
Percent int "flag:\"%\" help:\"debug non-static initializers\""
CompilingRuntime bool "flag:\"+\" help:\"compiling runtime\""
// Longer names
AsmHdr string "help:\"write assembly header to `file`\""
Bench string "help:\"append benchmark times to `file`\""
BlockProfile string "help:\"write block profile to `file`\""
BuildID string "help:\"record `id` as the build id in the export metadata\""
CPUProfile string "help:\"write cpu profile to `file`\""
Complete bool "help:\"compiling complete package (no C or assembly)\""
Dwarf bool "help:\"generate DWARF symbols\""
DwarfBASEntries *bool "help:\"use base address selection entries in DWARF\"" // &Ctxt.UseBASEntries, set below
DwarfLocationLists *bool "help:\"add location lists to DWARF in optimized mode\"" // &Ctxt.Flag_locationlists, set below
Dynlink *bool "help:\"support references to Go symbols defined in other shared libraries\"" // &Ctxt.Flag_dynlink, set below
EmbedCfg func(string) "help:\"read go:embed configuration from `file`\""
GenDwarfInl int "help:\"generate DWARF inline info records\"" // 0=disabled, 1=funcs, 2=funcs+formals/locals
GoVersion string "help:\"required version of the runtime\""
ImportCfg func(string) "help:\"read import configuration from `file`\""
ImportMap func(string) "help:\"add `definition` of the form source=actual to import map\""
InstallSuffix string "help:\"set pkg directory `suffix`\""
JSON string "help:\"version,file for JSON compiler/optimizer detail output\""
Lang string "help:\"Go language version source code expects\""
LinkObj string "help:\"write linker-specific object to `file`\""
LinkShared *bool "help:\"generate code that will be linked against Go shared libraries\"" // &Ctxt.Flag_linkshared, set below
Live CountFlag "help:\"debug liveness analysis\""
MSan bool "help:\"build code compatible with C/C++ memory sanitizer\""
MemProfile string "help:\"write memory profile to `file`\""
MemProfileRate int64 "help:\"set runtime.MemProfileRate to `rate`\""
MutexProfile string "help:\"write mutex profile to `file`\""
NoLocalImports bool "help:\"reject local (relative) imports\""
Pack bool "help:\"write to file.a instead of file.o\""
Race bool "help:\"enable race detector\""
Shared *bool "help:\"generate code that can be linked into a shared library\"" // &Ctxt.Flag_shared, set below
SmallFrames bool "help:\"reduce the size limit for stack allocated objects\"" // small stacks, to diagnose GC latency; see golang.org/issue/27732
Spectre string "help:\"enable spectre mitigations in `list` (all, index, ret)\""
Std bool "help:\"compiling standard library\""
SymABIs string "help:\"read symbol ABIs from `file`\""
TraceProfile string "help:\"write an execution trace to `file`\""
TrimPath string "help:\"remove `prefix` from recorded source file paths\""
WB bool "help:\"enable write barrier\"" // TODO: remove
// Configuration derived from flags; not a flag itself.
Cfg struct {
Embed struct {
Embed struct { // set by -embedcfg
Patterns map[string][]string
Files map[string]string
}
ImportDirs []string
ImportMap map[string]string
PackageFile map[string]string
SpectreIndex bool
ImportDirs []string // appended to by -I
ImportMap map[string]string // set by -importmap OR -importcfg
PackageFile map[string]string // set by -importcfg; nil means not in use
SpectreIndex bool // set by -spectre=index or -spectre=all
}
}
// ParseFlags parses the command-line flags into Flag.
func ParseFlags() {
Wasm := objabi.GOARCH == "wasm"
Flag.I = addImportDir
// Whether the limit for stack-allocated objects is much smaller than normal.
// This can be helpful for diagnosing certain causes of GC latency. See #27732.
Flag.SmallFrames = false
Flag.JSON = ""
Flag.LowerC = 1
Flag.LowerP = &Ctxt.Pkgpath
Flag.LowerV = &Ctxt.Debugvlog
flag.BoolVar(&Flag.CompilingRuntime, "+", false, "compiling runtime")
flag.BoolVar(&Flag.Std, "std", false, "compiling standard library")
flag.StringVar(&Flag.D, "D", "", "set relative `path` for local imports")
Flag.Dwarf = objabi.GOARCH != "wasm"
Flag.DwarfBASEntries = &Ctxt.UseBASEntries
Flag.DwarfLocationLists = &Ctxt.Flag_locationlists
*Flag.DwarfLocationLists = true
Flag.Dynlink = &Ctxt.Flag_dynlink
Flag.EmbedCfg = readEmbedCfg
Flag.GenDwarfInl = 2
Flag.ImportCfg = readImportCfg
Flag.ImportMap = addImportMap
Flag.LinkShared = &Ctxt.Flag_linkshared
Flag.Shared = &Ctxt.Flag_shared
Flag.WB = true
objabi.Flagcount("%", "debug non-static initializers", &Flag.Percent)
objabi.Flagcount("B", "disable bounds checking", &Flag.B)
objabi.Flagcount("C", "disable printing of columns in error messages", &Flag.C)
objabi.Flagcount("E", "debug symbol export", &Flag.E)
objabi.Flagcount("K", "debug missing line numbers", &Flag.K)
objabi.Flagcount("L", "show full file names in error messages", &Flag.L)
objabi.Flagcount("N", "disable optimizations", &Flag.N)
objabi.Flagcount("S", "print assembly listing", &Flag.S)
objabi.Flagcount("W", "debug parse tree after type checking", &Flag.W)
objabi.Flagcount("e", "no limit on number of errors reported", &Flag.LowerE)
objabi.Flagcount("h", "halt on error", &Flag.LowerH)
objabi.Flagcount("j", "debug runtime-initialized variables", &Flag.LowerJ)
objabi.Flagcount("l", "disable inlining", &Flag.LowerL)
objabi.Flagcount("m", "print optimization decisions", &Flag.LowerM)
objabi.Flagcount("r", "debug generated wrappers", &Flag.LowerR)
objabi.Flagcount("w", "debug type checking", &Flag.LowerW)
Flag.Cfg.ImportMap = make(map[string]string)
objabi.Flagfn1("I", "add `directory` to import search path", addImportDir)
objabi.AddVersionFlag() // -V
flag.StringVar(&Flag.AsmHdr, "asmhdr", "", "write assembly header to `file`")
flag.StringVar(&Flag.BuildID, "buildid", "", "record `id` as the build id in the export metadata")
flag.IntVar(&Flag.LowerC, "c", 1, "concurrency during compilation, 1 means no concurrency")
flag.BoolVar(&Flag.Complete, "complete", false, "compiling complete package (no C or assembly)")
flag.StringVar(&Flag.LowerD, "d", "", "print debug information about items in `list`; try -d help")
flag.BoolVar(&Flag.Dwarf, "dwarf", !Wasm, "generate DWARF symbols")
flag.BoolVar(&Ctxt.Flag_locationlists, "dwarflocationlists", true, "add location lists to DWARF in optimized mode")
flag.IntVar(&Flag.GenDwarfInl, "gendwarfinl", 2, "generate DWARF inline info records")
objabi.Flagfn1("embedcfg", "read go:embed configuration from `file`", readEmbedCfg)
objabi.Flagfn1("importmap", "add `definition` of the form source=actual to import map", addImportMap)
objabi.Flagfn1("importcfg", "read import configuration from `file`", readImportCfg)
flag.StringVar(&Flag.InstallSuffix, "installsuffix", "", "set pkg directory `suffix`")
flag.StringVar(&Flag.Lang, "lang", "", "release to compile for")
flag.StringVar(&Flag.LinkObj, "linkobj", "", "write linker-specific object to `file`")
objabi.Flagcount("live", "debug liveness analysis", &Flag.Live)
if sys.MSanSupported(objabi.GOOS, objabi.GOARCH) {
flag.BoolVar(&Flag.MSan, "msan", false, "build code compatible with C/C++ memory sanitizer")
}
flag.BoolVar(&Flag.NoLocalImports, "nolocalimports", false, "reject local (relative) imports")
flag.StringVar(&Flag.LowerO, "o", "", "write output to `file`")
flag.StringVar(&Ctxt.Pkgpath, "p", "", "set expected package import `path`")
flag.BoolVar(&Flag.Pack, "pack", false, "write to file.a instead of file.o")
if sys.RaceDetectorSupported(objabi.GOOS, objabi.GOARCH) {
flag.BoolVar(&Flag.Race, "race", false, "enable race detector")
}
flag.StringVar(&Flag.Spectre, "spectre", Flag.Spectre, "enable spectre mitigations in `list` (all, index, ret)")
if enableTrace {
flag.BoolVar(&Flag.LowerT, "t", false, "trace type-checking")
}
flag.StringVar(&Flag.TrimPath, "trimpath", "", "remove `prefix` from recorded source file paths")
flag.BoolVar(&Ctxt.Debugvlog, "v", false, "increase debug verbosity")
flag.BoolVar(&Flag.WB, "wb", true, "enable write barrier")
if supportsDynlink(thearch.LinkArch.Arch) {
flag.BoolVar(&Flag.Shared, "shared", false, "generate code that can be linked into a shared library")
flag.BoolVar(&Flag.Dynlink, "dynlink", false, "support references to Go symbols defined in other shared libraries")
flag.BoolVar(&Ctxt.Flag_linkshared, "linkshared", false, "generate code that will be linked against Go shared libraries")
}
flag.StringVar(&Flag.CPUProfile, "cpuprofile", "", "write cpu profile to `file`")
flag.StringVar(&Flag.MemProfile, "memprofile", "", "write memory profile to `file`")
flag.Int64Var(&memprofilerate, "memprofilerate", 0, "set runtime.MemProfileRate to `rate`")
flag.StringVar(&Flag.GoVersion, "goversion", "", "required version of the runtime")
flag.StringVar(&Flag.SymABIs, "symabis", "", "read symbol ABIs from `file`")
flag.StringVar(&Flag.TraceProfile, "traceprofile", "", "write an execution trace to `file`")
flag.StringVar(&Flag.BlockProfile, "blockprofile", "", "write block profile to `file`")
flag.StringVar(&Flag.MutexProfile, "mutexprofile", "", "write mutex profile to `file`")
flag.StringVar(&Flag.Bench, "bench", "", "append benchmark times to `file`")
flag.BoolVar(&Flag.SmallFrames, "smallframes", false, "reduce the size limit for stack allocated objects")
flag.BoolVar(&Ctxt.UseBASEntries, "dwarfbasentries", Ctxt.UseBASEntries, "use base address selection entries in DWARF")
flag.StringVar(&Flag.JSON, "json", "", "version,destination for JSON compiler/optimizer logging")
registerFlags()
objabi.Flagparse(usage)
for _, f := range strings.Split(Flag.Spectre, ",") {
f = strings.TrimSpace(f)
switch f {
default:
log.Fatalf("unknown setting -spectre=%s", f)
case "":
// nothing
case "all":
Flag.Cfg.SpectreIndex = true
Ctxt.Retpoline = true
case "index":
Flag.Cfg.SpectreIndex = true
case "ret":
Ctxt.Retpoline = true
}
if Flag.MSan && !sys.MSanSupported(objabi.GOOS, objabi.GOARCH) {
log.Fatalf("%s/%s does not support -msan", objabi.GOOS, objabi.GOARCH)
}
if Flag.Cfg.SpectreIndex {
switch objabi.GOARCH {
case "amd64":
// ok
default:
log.Fatalf("GOARCH=%s does not support -spectre=index", objabi.GOARCH)
}
if Flag.Race && !sys.RaceDetectorSupported(objabi.GOOS, objabi.GOARCH) {
log.Fatalf("%s/%s does not support -race", objabi.GOOS, objabi.GOARCH)
}
// Record flags that affect the build result. (And don't
// record flags that don't, since that would cause spurious
// changes in the binary.)
recordFlags("B", "N", "l", "msan", "race", "shared", "dynlink", "dwarflocationlists", "dwarfbasentries", "smallframes", "spectre")
if Flag.SmallFrames {
maxStackVarSize = 128 * 1024
maxImplicitStackVarSize = 16 * 1024
if (*Flag.Shared || *Flag.Dynlink || *Flag.LinkShared) && !Ctxt.Arch.InFamily(sys.AMD64, sys.ARM, sys.ARM64, sys.I386, sys.PPC64, sys.RISCV64, sys.S390X) {
log.Fatalf("%s/%s does not support -shared", objabi.GOOS, objabi.GOARCH)
}
parseSpectre(Flag.Spectre) // left as string for recordFlags
Ctxt.Flag_shared = Flag.Dynlink || Flag.Shared
Ctxt.Flag_dynlink = Flag.Dynlink
Ctxt.Flag_shared = Ctxt.Flag_dynlink || Ctxt.Flag_shared
Ctxt.Flag_optimize = Flag.N == 0
Ctxt.Debugasm = Flag.S
if Flag.Dwarf {
Ctxt.DebugInfo = debuginfo
Ctxt.GenAbstractFunc = genAbstractFunc
Ctxt.DwFixups = obj.NewDwarfFixupTable(Ctxt)
} else {
// turn off inline generation if no dwarf at all
Flag.GenDwarfInl = 0
Ctxt.Flag_locationlists = false
}
Ctxt.Debugasm = int(Flag.S)
if flag.NArg() < 1 && Flag.LowerD != "help" && Flag.LowerD != "ssa/help" {
usage()
@ -229,14 +184,6 @@ func ParseFlags() {
Exit(2)
}
checkLang()
if Flag.SymABIs != "" {
readSymABIs(Flag.SymABIs, Ctxt.Pkgpath)
}
thearch.LinkArch.Init(Ctxt)
if Flag.LowerO == "" {
p := flag.Arg(0)
if i := strings.LastIndex(p, "/"); i >= 0 {
@ -257,8 +204,6 @@ func ParseFlags() {
Flag.LowerO = p + suffix
}
startProfile()
if Flag.Race && Flag.MSan {
log.Fatal("cannot use both -race and -msan")
}
@ -266,19 +211,6 @@ func ParseFlags() {
// -race and -msan imply -d=checkptr for now.
Debug_checkptr = 1
}
if ispkgin(omit_pkgs) {
Flag.Race = false
Flag.MSan = false
}
if Flag.Race {
racepkg = types.NewPkg("runtime/race", "")
}
if Flag.MSan {
msanpkg = types.NewPkg("runtime/msan", "")
}
if Flag.Race || Flag.MSan {
instrumenting = true
}
if Flag.CompilingRuntime && Flag.N != 0 {
log.Fatal("cannot disable optimizations while compiling runtime")
@ -289,9 +221,6 @@ func ParseFlags() {
if Flag.LowerC > 1 && !concurrentBackendAllowed() {
log.Fatalf("cannot use concurrent backend compilation with provided flags; invoked as %v", os.Args)
}
if Ctxt.Flag_locationlists && len(Ctxt.Arch.DWARFRegisters) == 0 {
log.Fatalf("location lists requested but register mapping not available on %v", Ctxt.Arch.Name)
}
// parse -d argument
if Flag.LowerD != "" {
@ -376,24 +305,77 @@ func ParseFlags() {
// set via a -d flag
Ctxt.Debugpcln = Debug_pctab
if Flag.Dwarf {
dwarf.EnableLogging(Debug_gendwarfinl != 0)
}
}
if Debug_softfloat != 0 {
thearch.SoftFloat = true
}
// registerFlags adds flag registrations for all the fields in Flag.
// See the comment on type CmdFlags for the rules.
func registerFlags() {
var (
boolType = reflect.TypeOf(bool(false))
intType = reflect.TypeOf(int(0))
stringType = reflect.TypeOf(string(""))
ptrBoolType = reflect.TypeOf(new(bool))
ptrIntType = reflect.TypeOf(new(int))
ptrStringType = reflect.TypeOf(new(string))
countType = reflect.TypeOf(CountFlag(0))
funcType = reflect.TypeOf((func(string))(nil))
)
// enable inlining. for now:
// default: inlining on. (Debug.l == 1)
// -l: inlining off (Debug.l == 0)
// -l=2, -l=3: inlining on again, with extra debugging (Debug.l > 1)
if Flag.LowerL <= 1 {
Flag.LowerL = 1 - Flag.LowerL
}
v := reflect.ValueOf(&Flag).Elem()
t := v.Type()
for i := 0; i < t.NumField(); i++ {
f := t.Field(i)
if f.Name == "Cfg" {
continue
}
if Flag.JSON != "" { // parse version,destination from json logging optimization.
logopt.LogJsonOption(Flag.JSON)
var name string
if len(f.Name) == 1 {
name = f.Name
} else if len(f.Name) == 6 && f.Name[:5] == "Lower" && 'A' <= f.Name[5] && f.Name[5] <= 'Z' {
name = string(rune(f.Name[5] + 'a' - 'A'))
} else {
name = strings.ToLower(f.Name)
}
if tag := f.Tag.Get("flag"); tag != "" {
name = tag
}
help := f.Tag.Get("help")
if help == "" {
panic(fmt.Sprintf("base.Flag.%s is missing help text", f.Name))
}
if k := f.Type.Kind(); (k == reflect.Ptr || k == reflect.Func) && v.Field(i).IsNil() {
panic(fmt.Sprintf("base.Flag.%s is uninitialized %v", f.Name, f.Type))
}
switch f.Type {
case boolType:
p := v.Field(i).Addr().Interface().(*bool)
flag.BoolVar(p, name, *p, help)
case intType:
p := v.Field(i).Addr().Interface().(*int)
flag.IntVar(p, name, *p, help)
case stringType:
p := v.Field(i).Addr().Interface().(*string)
flag.StringVar(p, name, *p, help)
case ptrBoolType:
p := v.Field(i).Interface().(*bool)
flag.BoolVar(p, name, *p, help)
case ptrIntType:
p := v.Field(i).Interface().(*int)
flag.IntVar(p, name, *p, help)
case ptrStringType:
p := v.Field(i).Interface().(*string)
flag.StringVar(p, name, *p, help)
case countType:
p := (*int)(v.Field(i).Addr().Interface().(*CountFlag))
objabi.Flagcount(name, help, p)
case funcType:
f := v.Field(i).Interface().(func(string))
objabi.Flagfn1(name, help, f)
}
}
}
@ -514,3 +496,32 @@ func readEmbedCfg(file string) {
log.Fatalf("%s: invalid embedcfg: missing Files", file)
}
}
// parseSpectre parses the spectre configuration from the string s.
func parseSpectre(s string) {
for _, f := range strings.Split(s, ",") {
f = strings.TrimSpace(f)
switch f {
default:
log.Fatalf("unknown setting -spectre=%s", f)
case "":
// nothing
case "all":
Flag.Cfg.SpectreIndex = true
Ctxt.Retpoline = true
case "index":
Flag.Cfg.SpectreIndex = true
case "ret":
Ctxt.Retpoline = true
}
}
if Flag.Cfg.SpectreIndex {
switch objabi.GOARCH {
case "amd64":
// ok
default:
log.Fatalf("GOARCH=%s does not support -spectre=index", objabi.GOARCH)
}
}
}

View file

@ -18,7 +18,6 @@ import (
"cmd/internal/obj"
"cmd/internal/objabi"
"cmd/internal/src"
"cmd/internal/sys"
"flag"
"fmt"
"go/constant"
@ -118,12 +117,6 @@ func hidePanic() {
}
}
// supportsDynlink reports whether or not the code generator for the given
// architecture supports the -shared and -dynlink flags.
func supportsDynlink(arch *sys.Arch) bool {
return arch.InFamily(sys.AMD64, sys.ARM, sys.ARM64, sys.I386, sys.PPC64, sys.RISCV64, sys.S390X)
}
// timing data for compiler phases
var timings Timings
@ -192,6 +185,74 @@ func Main(archInit func(*Arch)) {
ParseFlags()
// Record flags that affect the build result. (And don't
// record flags that don't, since that would cause spurious
// changes in the binary.)
recordFlags("B", "N", "l", "msan", "race", "shared", "dynlink", "dwarflocationlists", "dwarfbasentries", "smallframes", "spectre")
if !enableTrace && Flag.LowerT {
log.Fatalf("compiler not built with support for -t")
}
// Enable inlining (after recordFlags, to avoid recording the rewritten -l). For now:
// default: inlining on. (Flag.LowerL == 1)
// -l: inlining off (Flag.LowerL == 0)
// -l=2, -l=3: inlining on again, with extra debugging (Flag.LowerL > 1)
if Flag.LowerL <= 1 {
Flag.LowerL = 1 - Flag.LowerL
}
if Flag.SmallFrames {
maxStackVarSize = 128 * 1024
maxImplicitStackVarSize = 16 * 1024
}
if Flag.Dwarf {
Ctxt.DebugInfo = debuginfo
Ctxt.GenAbstractFunc = genAbstractFunc
Ctxt.DwFixups = obj.NewDwarfFixupTable(Ctxt)
} else {
// turn off inline generation if no dwarf at all
Flag.GenDwarfInl = 0
Ctxt.Flag_locationlists = false
}
if Ctxt.Flag_locationlists && len(Ctxt.Arch.DWARFRegisters) == 0 {
log.Fatalf("location lists requested but register mapping not available on %v", Ctxt.Arch.Name)
}
checkLang()
if Flag.SymABIs != "" {
readSymABIs(Flag.SymABIs, Ctxt.Pkgpath)
}
if ispkgin(omit_pkgs) {
Flag.Race = false
Flag.MSan = false
}
thearch.LinkArch.Init(Ctxt)
startProfile()
if Flag.Race {
racepkg = types.NewPkg("runtime/race", "")
}
if Flag.MSan {
msanpkg = types.NewPkg("runtime/msan", "")
}
if Flag.Race || Flag.MSan {
instrumenting = true
}
if Flag.Dwarf {
dwarf.EnableLogging(Debug_gendwarfinl != 0)
}
if Debug_softfloat != 0 {
thearch.SoftFloat = true
}
if Flag.JSON != "" { // parse version,destination from json logging optimization.
logopt.LogJsonOption(Flag.JSON)
}
ssaDump = os.Getenv("GOSSAFUNC")
ssaDir = os.Getenv("GOSSADIR")
if ssaDump != "" {