blob: e8535ae9ac9d92497ba4b9d6377204d1d32398f6 [file] [log] [blame]
// Copyright 2015 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.
// Package flags implements top-level flags and the usage message for the assembler.
package flags
import (
"cmd/internal/objabi"
"flag"
"fmt"
"os"
"path/filepath"
"strings"
)
var (
Debug = flag.Bool("debug", false, "dump instructions as they are parsed")
OutputFile = flag.String("o", "", "output file; default foo.o for /a/b/c/foo.s as first argument")
PrintOut = flag.Bool("S", false, "print assembly and machine code")
TrimPath = flag.String("trimpath", "", "remove prefix from recorded source file paths")
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("gensymabis", false, "write symbol ABI information to output file, don't assemble")
Importpath = flag.String("p", "", "set expected package import to path")
Spectre = flag.String("spectre", "", "enable spectre mitigations in `list` (all, ret)")
Go115Newobj = flag.Bool("go115newobj", true, "use new object file format")
)
var (
D MultiFlag
I MultiFlag
)
func init() {
flag.Var(&D, "D", "predefined symbol with optional simple value -D=identifier=value; can be set multiple times")
flag.Var(&I, "I", "include directory; can be set multiple times")
objabi.AddVersionFlag() // -V
}
// MultiFlag allows setting a value multiple times to collect a list, as in -I=dir1 -I=dir2.
type MultiFlag []string
func (m *MultiFlag) String() string {
if len(*m) == 0 {
return ""
}
return fmt.Sprint(*m)
}
func (m *MultiFlag) Set(val string) error {
(*m) = append(*m, val)
return nil
}
func Usage() {
fmt.Fprintf(os.Stderr, "usage: asm [options] file.s ...\n")
fmt.Fprintf(os.Stderr, "Flags:\n")
flag.PrintDefaults()
os.Exit(2)
}
func Parse() {
flag.Usage = Usage
flag.Parse()
if flag.NArg() == 0 {
flag.Usage()
}
// Flag refinement.
if *OutputFile == "" {
if flag.NArg() != 1 {
flag.Usage()
}
input := filepath.Base(flag.Arg(0))
if strings.HasSuffix(input, ".s") {
input = input[:len(input)-2]
}
*OutputFile = fmt.Sprintf("%s.o", input)
}
}