| // Copyright 2018 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. |
| |
| // +build ignore |
| |
| // mkasm.go generates assembly trampolines to call library routines from Go. |
| // This program must be run after mksyscall.pl. |
| package main |
| |
| import ( |
| "bytes" |
| "fmt" |
| "log" |
| "os" |
| "strings" |
| ) |
| |
| func main() { |
| if len(os.Args) != 3 { |
| log.Fatalf("Usage: %s <goos> <arch>", os.Args[0]) |
| } |
| goos, arch := os.Args[1], os.Args[2] |
| |
| syscallFilename := fmt.Sprintf("syscall_%s.go", goos) |
| syscallArchFilename := fmt.Sprintf("syscall_%s_%s.go", goos, arch) |
| |
| in1, err := os.ReadFile(syscallFilename) |
| if err != nil { |
| log.Fatalf("can't open syscall file: %s", err) |
| } |
| in2, err := os.ReadFile(syscallArchFilename) |
| if err != nil { |
| log.Fatalf("can't open syscall file: %s", err) |
| } |
| in3, err := os.ReadFile("z" + syscallArchFilename) |
| if err != nil { |
| log.Fatalf("can't open syscall file: %s", err) |
| } |
| in := string(in1) + string(in2) + string(in3) |
| |
| trampolines := map[string]bool{} |
| |
| var out bytes.Buffer |
| |
| fmt.Fprintf(&out, "// go run mkasm.go %s\n", strings.Join(os.Args[1:], " ")) |
| fmt.Fprintf(&out, "// Code generated by the command above; DO NOT EDIT.\n") |
| fmt.Fprintf(&out, "#include \"textflag.h\"\n") |
| for _, line := range strings.Split(in, "\n") { |
| if !strings.HasPrefix(line, "func ") || !strings.HasSuffix(line, "_trampoline()") { |
| continue |
| } |
| fn := line[5 : len(line)-13] |
| if !trampolines[fn] { |
| trampolines[fn] = true |
| fmt.Fprintf(&out, "TEXT ยท%s_trampoline(SB),NOSPLIT,$0-0\n", fn) |
| fmt.Fprintf(&out, "\tJMP\t%s(SB)\n", fn) |
| } |
| } |
| err = os.WriteFile(fmt.Sprintf("zsyscall_%s_%s.s", goos, arch), out.Bytes(), 0644) |
| if err != nil { |
| log.Fatalf("can't write syscall file: %s", err) |
| } |
| } |