cmd/asm: rename -symabis to -gensymabis

Currently, both asm and compile have a -symabis flag, but in asm it's
a boolean flag that means to generate a symbol ABIs file and in the
compiler its a string flag giving the path of the symbol ABIs file to
consume. I'm worried about this false symmetry biting us in the
future, so rename asm's flag to -gensymabis.

Updates #27539.

Change-Id: I8b9c18a852d2838099718f8989813f19d82e7434
Reviewed-on: https://go-review.googlesource.com/c/149818
Run-TryBot: Austin Clements <austin@google.com>
TryBot-Result: Gobot Gobot <gobot@golang.org>
Reviewed-by: Ian Lance Taylor <iant@golang.org>

Author: aclements

src/cmd/asm/doc.go

@@ -39,6 +39,8 @@ Flags:
 		Generate code that can be linked into a shared library.
 	-trimpath prefix
 		Remove prefix from recorded source file paths.
+	-gensymabis
+		Write symbol ABI information to output file. Don't assemble.
 Input language:
 
 The assembler uses mostly the same syntax for all architectures,

src/cmd/asm/internal/flags/flags.go

@@ -22,7 +22,7 @@ var (
 	Shared     = flag.Bool("shared", false, "generate code that can be linked into a shared library")
 	Dynlink    = flag.Bool("dynlink", false, "support references to Go symbols defined in other shared libraries")
 	AllErrors  = flag.Bool("e", false, "no limit on number of errors reported")
-	SymABIs    = flag.Bool("symabis", false, "write symbol ABI information to output file, don't assemble")
+	SymABIs    = flag.Bool("gensymabis", false, "write symbol ABI information to output file, don't assemble")
 )
 
 var (

src/cmd/dist/build.go

@@ -804,7 +804,7 @@ func runInstall(dir string, ch chan struct{}) {
 	if len(sfiles) > 0 {
 		symabis = pathf("%s/symabis", workdir)
 		var wg sync.WaitGroup
-		asmabis := append(asmArgs[:len(asmArgs):len(asmArgs)], "-symabis", "-o", symabis)
+		asmabis := append(asmArgs[:len(asmArgs):len(asmArgs)], "-gensymabis", "-o", symabis)
 		asmabis = append(asmabis, sfiles...)
 		if err := ioutil.WriteFile(goasmh, nil, 0666); err != nil {
 			fatalf("cannot write empty go_asm.h: %s", err)

src/cmd/go/internal/work/gc.go

@@ -265,7 +265,7 @@ func (gcToolchain) asm(b *Builder, a *Action, sfiles []string) ([]string, error)
 func (gcToolchain) symabis(b *Builder, a *Action, sfiles []string) (string, error) {
 	mkSymabis := func(p *load.Package, sfiles []string, path string) error {
 		args := asmArgs(a, p)
-		args = append(args, "-symabis", "-o", path)
+		args = append(args, "-gensymabis", "-o", path)
 		for _, sfile := range sfiles {
 			if p.ImportPath == "runtime/cgo" && strings.HasPrefix(sfile, "gcc_") {
 				continue
@@ -274,7 +274,7 @@ func (gcToolchain) symabis(b *Builder, a *Action, sfiles []string) (string, erro
 		}
 
 		// Supply an empty go_asm.h as if the compiler had been run.
-		// -symabis parsing is lax enough that we don't need the
+		// -gensymabis parsing is lax enough that we don't need the
 		// actual definitions that would appear in go_asm.h.
 		if err := b.writeFile(a.Objdir+"go_asm.h", nil); err != nil {
 			return err

test/run.go

@@ -813,7 +813,7 @@ func (t *test) run() {
 				t.err = fmt.Errorf("write empty go_asm.h: %s", err)
 				return
 			}
-			cmd := []string{goTool(), "tool", "asm", "-symabis", "-o", "symabis"}
+			cmd := []string{goTool(), "tool", "asm", "-gensymabis", "-o", "symabis"}
 			cmd = append(cmd, asms...)
 			_, err = runcmd(cmd...)
 			if err != nil {