1 files changed, 45 insertions, 0 deletions
diff --git a/src/cmd/internal/goobj/builtin.go b/src/cmd/internal/goobj/builtin.go
new file mode 100644
index 0000000..e7d612a
--- /dev/null
+++ b/src/cmd/internal/goobj/builtin.go
@@ -0,0 +1,45 @@
+// Copyright 2019 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 goobj
+
+// Builtin (compiler-generated) function references appear
+// frequently. We assign special indices for them, so they
+// don't need to be referenced by name.
+
+// NBuiltin returns the number of listed builtin
+// symbols.
+func NBuiltin() int {
+	return len(builtins)
+}
+
+// BuiltinName returns the name and ABI of the i-th
+// builtin symbol.
+func BuiltinName(i int) (string, int) {
+	return builtins[i].name, builtins[i].abi
+}
+
+// BuiltinIdx returns the index of the builtin with the
+// given name and abi, or -1 if it is not a builtin.
+func BuiltinIdx(name string, abi int) int {
+	i, ok := builtinMap[name]
+	if !ok {
+		return -1
+	}
+	if builtins[i].abi != abi {
+		return -1
+	}
+	return i
+}
+
+//go:generate go run mkbuiltin.go
+
+var builtinMap map[string]int
+
+func init() {
+	builtinMap = make(map[string]int, len(builtins))
+	for i, b := range builtins {
+		builtinMap[b.name] = i
+	}
+}