tools/llvm-go/llvm-go.go

   1 //===-- llvm-go.go - go tool wrapper for LLVM -----------------------------===//
   2 //
   3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
   4 // See https://llvm.org/LICENSE.txt for license information.
   5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
   6 //
   7 //===----------------------------------------------------------------------===//
   8 //
   9 // This tool lets us build LLVM components within the tree by setting up a
  10 // $GOPATH that resembles a tree fetched in the normal way with "go get".
  11 //
  12 //===----------------------------------------------------------------------===//
  13
  14 package main
  15
  16 import (
  17         "fmt"
  18         "io/ioutil"
  19         "os"
  20         "os/exec"
  21         "path/filepath"
  22         "runtime"
  23         "strings"
  24 )
  25
  26 const (
  27         linkmodeComponentLibs = "component-libs"
  28         linkmodeDylib         = "dylib"
  29 )
  30
  31 type pkg struct {
  32         llvmpath, pkgpath string
  33 }
  34
  35 var packages = []pkg{
  36         {"bindings/go/llvm", "llvm.org/llvm/bindings/go/llvm"},
  37 }
  38
  39 type compilerFlags struct {
  40         cpp, cxx, ld string
  41 }
  42
  43 var components = []string{
  44         "all-targets",
  45         "analysis",
  46         "asmparser",
  47         "asmprinter",
  48         "bitreader",
  49         "bitwriter",
  50         "codegen",
  51         "core",
  52         "coroutines",
  53         "debuginfodwarf",
  54         "executionengine",
  55         "instrumentation",
  56         "interpreter",
  57         "ipo",
  58         "irreader",
  59         "linker",
  60         "mc",
  61         "mcjit",
  62         "objcarcopts",
  63         "option",
  64         "profiledata",
  65         "scalaropts",
  66         "support",
  67         "target",
  68 }
  69
  70 func llvmConfig(args ...string) string {
  71         configpath := os.Getenv("LLVM_CONFIG")
  72         if configpath == "" {
  73                 bin, _ := filepath.Split(os.Args[0])
  74                 configpath = filepath.Join(bin, "llvm-config")
  75         }
  76
  77         cmd := exec.Command(configpath, args...)
  78         cmd.Stderr = os.Stderr
  79         out, err := cmd.Output()
  80         if err != nil {
  81                 panic(err.Error())
  82         }
  83
  84         outstr := string(out)
  85         outstr = strings.TrimSuffix(outstr, "\n")
  86         outstr = strings.Replace(outstr, "\n", " ", -1)
  87         return outstr
  88 }
  89
  90 func llvmFlags() compilerFlags {
  91         args := append([]string{"--ldflags", "--libs", "--system-libs"}, components...)
  92         ldflags := llvmConfig(args...)
  93         if runtime.GOOS != "darwin" {
  94                 // OS X doesn't like -rpath with cgo. See:
  95                 // https://github.com/golang/go/issues/7293
  96                 ldflags = "-Wl,-rpath," + llvmConfig("--libdir") + " " + ldflags
  97         }
  98         return compilerFlags{
  99                 cpp: llvmConfig("--cppflags"),
 100                 cxx: "-std=c++11",
 101                 ld:  ldflags,
 102         }
 103 }
 104
 105 func addTag(args []string, tag string) []string {
 106         args = append([]string{}, args...)
 107         addedTag := false
 108         for i, a := range args {
 109                 if strings.HasPrefix(a, "-tags=") {
 110                         args[i] = a + " " + tag
 111                         addedTag = true
 112                 } else if a == "-tags" && i+1 < len(args) {
 113                         args[i+1] = args[i+1] + " " + tag
 114                         addedTag = true
 115                 }
 116         }
 117         if !addedTag {
 118                 args = append([]string{args[0], "-tags", tag}, args[1:]...)
 119         }
 120         return args
 121 }
 122
 123 func printComponents() {
 124         fmt.Println(strings.Join(components, " "))
 125 }
 126
 127 func printConfig() {
 128         flags := llvmFlags()
 129
 130         fmt.Printf(`// +build !byollvm
 131
 132 // This file is generated by llvm-go, do not edit.
 133
 134 package llvm
 135
 136 /*
 137 #cgo CPPFLAGS: %s
 138 #cgo CXXFLAGS: %s
 139 #cgo LDFLAGS: %s
 140 */
 141 import "C"
 142
 143 type (run_build_sh int)
 144 `, flags.cpp, flags.cxx, flags.ld)
 145 }
 146
 147 func runGoWithLLVMEnv(args []string, cc, cxx, gocmd, llgo, cppflags, cxxflags, ldflags string, packages []pkg) {
 148         args = addTag(args, "byollvm")
 149
 150         srcdir := llvmConfig("--src-root")
 151
 152         tmpgopath, err := ioutil.TempDir("", "gopath")
 153         if err != nil {
 154                 panic(err.Error())
 155         }
 156
 157         for _, p := range packages {
 158                 path := filepath.Join(tmpgopath, "src", p.pkgpath)
 159                 err := os.MkdirAll(filepath.Dir(path), os.ModePerm)
 160                 if err != nil {
 161                         panic(err.Error())
 162                 }
 163
 164                 abspath := p.llvmpath
 165                 if !filepath.IsAbs(abspath) {
 166                         abspath = filepath.Join(srcdir, abspath)
 167                 }
 168
 169                 err = os.Symlink(abspath, path)
 170                 if err != nil {
 171                         panic(err.Error())
 172                 }
 173         }
 174
 175         newpath := os.Getenv("PATH")
 176
 177         newgopathlist := []string{tmpgopath}
 178         newgopathlist = append(newgopathlist, filepath.SplitList(os.Getenv("GOPATH"))...)
 179         newgopath := strings.Join(newgopathlist, string(filepath.ListSeparator))
 180
 181         flags := llvmFlags()
 182
 183         newenv := []string{
 184                 "CC=" + cc,
 185                 "CXX=" + cxx,
 186                 "CGO_CPPFLAGS=" + flags.cpp + " " + cppflags,
 187                 "CGO_CXXFLAGS=" + flags.cxx + " " + cxxflags,
 188                 "CGO_LDFLAGS=" + flags.ld + " " + ldflags,
 189                 "GOPATH=" + newgopath,
 190                 "PATH=" + newpath,
 191         }
 192         if llgo != "" {
 193                 newenv = append(newenv, "GCCGO="+llgo)
 194         }
 195
 196         for _, v := range os.Environ() {
 197                 if !strings.HasPrefix(v, "CC=") &&
 198                         !strings.HasPrefix(v, "CXX=") &&
 199                         !strings.HasPrefix(v, "CGO_CPPFLAGS=") &&
 200                         !strings.HasPrefix(v, "CGO_CXXFLAGS=") &&
 201                         !strings.HasPrefix(v, "CGO_LDFLAGS=") &&
 202                         !strings.HasPrefix(v, "GCCGO=") &&
 203                         !strings.HasPrefix(v, "GOPATH=") &&
 204                         !strings.HasPrefix(v, "PATH=") {
 205                         newenv = append(newenv, v)
 206                 }
 207         }
 208
 209         gocmdpath, err := exec.LookPath(gocmd)
 210         if err != nil {
 211                 panic(err.Error())
 212         }
 213
 214         proc, err := os.StartProcess(gocmdpath, append([]string{gocmd}, args...),
 215                 &os.ProcAttr{
 216                         Env:   newenv,
 217                         Files: []*os.File{os.Stdin, os.Stdout, os.Stderr},
 218                 })
 219         if err != nil {
 220                 panic(err.Error())
 221         }
 222         ps, err := proc.Wait()
 223         if err != nil {
 224                 panic(err.Error())
 225         }
 226
 227         os.RemoveAll(tmpgopath)
 228
 229         if !ps.Success() {
 230                 os.Exit(1)
 231         }
 232 }
 233
 234 func usage() {
 235         fmt.Println(`Usage: llvm-go subcommand [flags]
 236
 237 Available subcommands: build get install run test print-components print-config`)
 238         os.Exit(0)
 239 }
 240
 241 func main() {
 242         cc := os.Getenv("CC")
 243         cxx := os.Getenv("CXX")
 244         cppflags := os.Getenv("CGO_CPPFLAGS")
 245         cxxflags := os.Getenv("CGO_CXXFLAGS")
 246         ldflags := os.Getenv("CGO_LDFLAGS")
 247         gocmd := "go"
 248         llgo := ""
 249         packagesString := ""
 250
 251         flags := []struct {
 252                 name string
 253                 dest *string
 254         }{
 255                 {"cc", &cc},
 256                 {"cxx", &cxx},
 257                 {"go", &gocmd},
 258                 {"llgo", &llgo},
 259                 {"cppflags", &cppflags},
 260                 {"ldflags", &ldflags},
 261                 {"packages", &packagesString},
 262         }
 263
 264         args := os.Args[1:]
 265 LOOP:
 266         for {
 267                 if len(args) == 0 {
 268                         usage()
 269                 }
 270                 for _, flag := range flags {
 271                         if strings.HasPrefix(args[0], flag.name+"=") {
 272                                 *flag.dest = args[0][len(flag.name)+1:]
 273                                 args = args[1:]
 274                                 continue LOOP
 275                         }
 276                 }
 277                 break
 278         }
 279
 280         packages := packages
 281         if packagesString != "" {
 282                 for _, field := range strings.Fields(packagesString) {
 283                         pos := strings.IndexRune(field, '=')
 284                         if pos == -1 {
 285                                 fmt.Fprintf(os.Stderr, "invalid packages value %q, expected 'pkgpath=llvmpath [pkgpath=llvmpath ...]'\n", packagesString)
 286                                 os.Exit(1)
 287                         }
 288                         packages = append(packages, pkg{
 289                                 pkgpath:  field[:pos],
 290                                 llvmpath: field[pos+1:],
 291                         })
 292                 }
 293         }
 294
 295         switch args[0] {
 296         case "build", "get", "install", "run", "test":
 297                 runGoWithLLVMEnv(args, cc, cxx, gocmd, llgo, cppflags, cxxflags, ldflags, packages)
 298         case "print-components":
 299                 printComponents()
 300         case "print-config":
 301                 printConfig()
 302         default:
 303                 usage()
 304         }
 305 }