Rename 'intrinsic' to 'builtin'

This matches the term used in the WGSL spec.

Change-Id: I4603332b828450c126ef806f1064ed54f372013f
Reviewed-on: https://dawn-review.googlesource.com/c/tint/+/78787
Reviewed-by: James Price <jrprice@google.com>
Kokoro: Kokoro <noreply+kokoro@google.com>

tools/src/cmd/builtin-gen/main.go

@@ -0,0 +1,173 @@
+// Copyright 2021 The Tint Authors.
+//
+// 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.
+
+// builtin-gen parses the <tint>/src/builtins.def file, then scans the
+// project directory for '<file>.tmpl' files, to produce '<file>' source code
+// files.
+package main
+
+import (
+	"flag"
+	"fmt"
+	"io/ioutil"
+	"os"
+	"path/filepath"
+	"strings"
+
+	"dawn.googlesource.com/tint/tools/src/cmd/builtin-gen/gen"
+	"dawn.googlesource.com/tint/tools/src/cmd/builtin-gen/parser"
+	"dawn.googlesource.com/tint/tools/src/cmd/builtin-gen/resolver"
+	"dawn.googlesource.com/tint/tools/src/fileutils"
+	"dawn.googlesource.com/tint/tools/src/glob"
+)
+
+const defProjectRelPath = "src/builtins.def"
+
+func main() {
+	if err := run(); err != nil {
+		fmt.Println(err)
+		os.Exit(1)
+	}
+}
+
+func showUsage() {
+	fmt.Println(`
+builtin-gen generates the builtin table for the Tint compiler
+
+builtin-gen parses the <tint>/src/builtins.def file, then scans the project
+directory for '<file>.tmpl' files, to produce '<file>' source code files.
+
+usage:
+  builtin-gen
+
+optional flags:`)
+	flag.PrintDefaults()
+	fmt.Println(``)
+	os.Exit(1)
+}
+
+func run() error {
+	// Load the builtins definition file
+	projectRoot := fileutils.ProjectRoot()
+	defPath := filepath.Join(projectRoot, defProjectRelPath)
+
+	defSource, err := ioutil.ReadFile(defPath)
+	if err != nil {
+		return err
+	}
+
+	// Parse the definition file to produce an AST
+	ast, err := parser.Parse(string(defSource), defProjectRelPath)
+	if err != nil {
+		return err
+	}
+
+	// Resolve the AST to produce the semantic info
+	sem, err := resolver.Resolve(ast)
+	if err != nil {
+		return err
+	}
+
+	// Recursively find all the template files in the <tint>/src directory
+	files, err := glob.Scan(projectRoot, glob.MustParseConfig(`{
+		"paths": [{"include": [
+			"src/**.tmpl",
+			"test/**.tmpl"
+		]}]
+	}`))
+	if err != nil {
+		return err
+	}
+
+	// For each template file...
+	for _, relTmplPath := range files {
+		// Make tmplPath absolute
+		tmplPath := filepath.Join(projectRoot, relTmplPath)
+
+		// Read the template file
+		tmpl, err := ioutil.ReadFile(tmplPath)
+		if err != nil {
+			return fmt.Errorf("failed to open '%v': %w", tmplPath, err)
+		}
+
+		// Create or update the file at relpath if the file content has changed
+		// relpath is a path relative to the template
+		writeFile := func(relpath, body string) error {
+			// Write the common file header
+			sb := strings.Builder{}
+			sb.WriteString(fmt.Sprintf(header, filepath.ToSlash(relTmplPath), filepath.ToSlash(defProjectRelPath)))
+			sb.WriteString(body)
+			content := sb.String()
+			abspath := filepath.Join(filepath.Dir(tmplPath), relpath)
+			return writeFileIfChanged(abspath, content)
+		}
+
+		// Write the content generated using the template and semantic info
+		sb := strings.Builder{}
+		if err := gen.Generate(sem, string(tmpl), &sb, writeFile); err != nil {
+			return fmt.Errorf("while processing '%v': %w", tmplPath, err)
+		}
+
+		if body := sb.String(); body != "" {
+			_, tmplFileName := filepath.Split(tmplPath)
+			outFileName := strings.TrimSuffix(tmplFileName, ".tmpl")
+			if err := writeFile(outFileName, body); err != nil {
+				return err
+			}
+		}
+	}
+
+	return nil
+}
+
+// writes content to path if the file has changed
+func writeFileIfChanged(path, content string) error {
+	existing, err := ioutil.ReadFile(path)
+	if err == nil && string(existing) == content {
+		return nil // Not changed
+	}
+	if err := os.MkdirAll(filepath.Dir(path), 0777); err != nil {
+		return fmt.Errorf("failed to create directory for '%v': %w", path, err)
+	}
+	if err := ioutil.WriteFile(path, []byte(content), 0666); err != nil {
+		return fmt.Errorf("failed to write file '%v': %w", path, err)
+	}
+	return nil
+}
+
+const header = `// Copyright 2021 The Tint Authors.
+//
+// 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.
+
+////////////////////////////////////////////////////////////////////////////////
+// File generated by tools/builtin-gen
+// using the template:
+//   %v
+// and the builtin defintion file:
+//   %v
+//
+// Do not modify this file directly
+////////////////////////////////////////////////////////////////////////////////
+
+`