xtool: utilize llvm-config to find LLVM executables

chore/nmdump/nmdump.go

@@ -30,7 +30,7 @@ func main() {
 		return
 	}
 
-	nm := llvm.New().Nm()
+	nm := llvm.New("").Nm()
 	items, err := nm.List(os.Args[1])
 	for _, item := range items {
 		if item.File != "" {

chore/nmindex/nmindex.go

@@ -54,7 +54,7 @@ The commands are:
 }
 
 func makeIndex() {
-	env := llvm.New()
+	env := llvm.New("")
 	idxDir := indexDir()
 	os.MkdirAll(idxDir, 0755)
 

internal/build/build.go

@@ -37,8 +37,8 @@ import (
 	"github.com/goplus/llgo/cl"
 	"github.com/goplus/llgo/internal/packages"
 	"github.com/goplus/llgo/ssa/abi"
-	"github.com/goplus/llgo/xtool/clang"
 	"github.com/goplus/llgo/xtool/env"
+	"github.com/goplus/llgo/xtool/env/llvm"
 
 	llssa "github.com/goplus/llgo/ssa"
 	clangCheck "github.com/goplus/llgo/xtool/clang/check"
@@ -308,21 +308,29 @@ func linkMainPkg(pkg *packages.Package, pkgs []*aPackage, llFiles []string, conf
 	if app == "" {
 		app = filepath.Join(conf.BinPath, name+conf.AppExt)
 	}
-	const N = 6
-	args := make([]string, N, len(pkg.Imports)+len(llFiles)+(N+1))
-	args[0] = "-o"
-	args[1] = app
-	args[2] = "-Wno-override-module"
-	args[3] = "-Xlinker"
-	if runtime.GOOS == "darwin" { // ld64.lld (macOS)
-		args[4] = "-dead_strip"
-		args[5] = "" // It's ok to leave it empty, as we can assume libpthread is built-in on macOS.
-	} else { // ld.lld (Unix), lld-link (Windows), wasm-ld (WebAssembly)
-		args[4] = "--gc-sections"
-		args[5] = "-lpthread" // libpthread is built-in since glibc 2.34 (2021-08-01); we need to support earlier versions.
+	args := make([]string, 0, len(pkg.Imports)+len(llFiles)+10)
+	args = append(
+		args,
+		"-o", app,
+		"-fuse-ld=lld",
+		"-Wno-override-module",
+		// "-O2", // FIXME: This will cause TestFinalizer in _test/bdwgc.go to fail on macOS.
+	)
+	switch runtime.GOOS {
+	case "darwin": // ld64.lld (macOS)
+		args = append(
+			args,
+			"-Xlinker", "-dead_strip",
+		)
+	case "windows": // lld-link (Windows)
+		// TODO: Add options for Windows.
+	default: // ld.lld (Unix), wasm-ld (WebAssembly)
+		args = append(
+			args,
+			"-Xlinker", "--gc-sections",
+			"-lpthread", // libpthread is built-in since glibc 2.34 (2021-08-01); we need to support earlier versions.
+		)
 	}
-	//args[6] = "-fuse-ld=lld" // TODO(xsw): to check lld exists or not
-	//args[7] = "-O2"
 	needRuntime := false
 	needPyInit := false
 	packages.Visit([]*packages.Package{pkg}, nil, func(p *packages.Package) {
@@ -378,7 +386,7 @@ func linkMainPkg(pkg *packages.Package, pkgs []*aPackage, llFiles []string, conf
 	if verbose {
 		fmt.Fprintln(os.Stderr, "clang", args)
 	}
-	err := clang.New("").Exec(args...)
+	err := llvm.New("").Clang().Exec(args...)
 	check(err)
 
 	switch mode {
@@ -646,7 +654,7 @@ func clFile(cFile, expFile string, procFile func(linkFile string), verbose bool)
 	if verbose {
 		fmt.Fprintln(os.Stderr, "clang", args)
 	}
-	err := clang.New("").Exec(args...)
+	err := llvm.New("").Clang().Exec(args...)
 	check(err)
 	procFile(llFile)
 }

xtool/env/env.go

@@ -1,3 +1,19 @@
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
 package env
 
 import (

xtool/env/llvm/llvm.go

@@ -18,28 +18,73 @@ package llvm
 
 import (
 	"os"
+	"os/exec"
+	"path/filepath"
+	"strings"
 
+	"github.com/goplus/llgo/xtool/clang"
+	"github.com/goplus/llgo/xtool/llvm/llvmlink"
 	"github.com/goplus/llgo/xtool/nm"
 )
 
-type Env struct {
-	root     string
-	nmprefix string
-}
+// -----------------------------------------------------------------------------
 
-func New() *Env {
-	var nmprefix string
-	var root = os.Getenv("LLGO_LLVM_ROOT")
-	if root != "" {
-		nmprefix = root + "/bin/llvm-"
+// defaultLLVMConfigBin returns the default path to the llvm-config binary. It
+// checks the LLVM_CONFIG environment variable first, then searches in PATH. If
+// not found, it returns [ldLLVMConfigBin] as a last resort.
+func defaultLLVMConfigBin() string {
+	bin := os.Getenv("LLVM_CONFIG")
+	if bin != "" {
+		return bin
 	}
-	return &Env{root, nmprefix}
+	bin, _ = exec.LookPath("llvm-config")
+	if bin != "" {
+		return bin
+	}
+	return ldLLVMConfigBin
 }
 
-func (p *Env) Root() string {
-	return p.root
+// -----------------------------------------------------------------------------
+
+// Env represents an LLVM installation.
+type Env struct {
+	binDir string
 }
 
-func (p *Env) Nm() *nm.Cmd {
-	return nm.New(p.nmprefix + "nm")
+// New creates a new [Env] instance.
+func New(llvmConfigBin string) *Env {
+	if llvmConfigBin == "" {
+		llvmConfigBin = defaultLLVMConfigBin()
+	}
+
+	// Note that an empty binDir is acceptable. In this case, LLVM
+	// executables are assumed to be in PATH.
+	binDir, _ := exec.Command(llvmConfigBin, "--bindir").Output()
+
+	e := &Env{binDir: strings.TrimSpace(string(binDir))}
+	return e
 }
+
+// BinDir returns the directory containing LLVM executables. An empty string
+// means LLVM executables are assumed to be in PATH.
+func (e *Env) BinDir() string { return e.binDir }
+
+// Clang returns a new [clang.Cmd] instance.
+func (e *Env) Clang() *clang.Cmd {
+	bin := filepath.Join(e.BinDir(), "clang")
+	return clang.New(bin)
+}
+
+// Link returns a new [llvmlink.Cmd] instance.
+func (e *Env) Link() *llvmlink.Cmd {
+	bin := filepath.Join(e.BinDir(), "llvm-link")
+	return llvmlink.New(bin)
+}
+
+// Nm returns a new [nm.Cmd] instance.
+func (e *Env) Nm() *nm.Cmd {
+	bin := filepath.Join(e.BinDir(), "llvm-nm")
+	return nm.New(bin)
+}
+
+// -----------------------------------------------------------------------------

xtool/env/llvm/llvm_config_byollvm.go

@@ -0,0 +1,26 @@
+//go:build byollvm
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+// The word "byollvm" stands for "Bring Your Own LLVM" and is a build tag used
+// to indicate that the package is being built with a custom LLVM installation.
+
+package llvm
+
+// ldLLVMConfigBin is the path to the llvm-config binary. It shoud be set via
+// -ldflags when building the package.
+var ldLLVMConfigBin string

xtool/env/llvm/llvm_config_darwin_amd64_llvm14.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && amd64 && llvm14
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/local/opt/llvm@14/bin/llvm-config"

xtool/env/llvm/llvm_config_darwin_amd64_llvm15.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && amd64 && llvm15
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/local/opt/llvm@15/bin/llvm-config"

xtool/env/llvm/llvm_config_darwin_amd64_llvm16.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && amd64 && llvm16
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/local/opt/llvm@16/bin/llvm-config"

xtool/env/llvm/llvm_config_darwin_amd64_llvm17.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && amd64 && !llvm14 && !llvm15 && !llvm16
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/local/opt/llvm@17/bin/llvm-config"

xtool/env/llvm/llvm_config_darwin_llvm14.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && !amd64 && llvm14
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/opt/homebrew/opt/llvm@14/bin/llvm-config"

xtool/env/llvm/llvm_config_darwin_llvm15.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && !amd64 && llvm15
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/opt/homebrew/opt/llvm@15/bin/llvm-config"

xtool/env/llvm/llvm_config_darwin_llvm16.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && !amd64 && llvm16
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/opt/homebrew/opt/llvm@16/bin/llvm-config"

xtool/env/llvm/llvm_config_darwin_llvm17.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && darwin && !amd64 && !llvm14 && !llvm15 && !llvm16
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/opt/homebrew/opt/llvm@17/bin/llvm-config"

xtool/env/llvm/llvm_config_linux_llvm14.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && linux && llvm14
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/lib/llvm-14/bin/llvm-config"

xtool/env/llvm/llvm_config_linux_llvm15.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && linux && llvm15
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/lib/llvm-15/bin/llvm-config"

xtool/env/llvm/llvm_config_linux_llvm16.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && linux && llvm16
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/lib/llvm-16/bin/llvm-config"

xtool/env/llvm/llvm_config_linux_llvm17.go

@@ -0,0 +1,21 @@
+//go:build !byollvm && linux && !llvm14 && !llvm15 && !llvm16
+
+/*
+ * Copyright (c) 2024 The GoPlus Authors (goplus.org). All rights reserved.
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ *     http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+package llvm
+
+const ldLLVMConfigBin = "/usr/lib/llvm-17/bin/llvm-config"

xtool/llvm/llvmlink/link.go

@@ -35,7 +35,7 @@ type Cmd struct {
 // New creates a new llvm-link command.
 func New(app string) *Cmd {
 	if app == "" {
-		app = os.Getenv("LLGO_LLVM_ROOT") + "/bin/llvm-link"
+		app = "llvm-link"
 	}
 	return &Cmd{app, os.Stdout, os.Stderr}
 }