AFDO for Rust

Bug: 195134194
Bug: 165018530
Test: build
Change-Id: I30932a22dc0b22716cdc925a3fcc5f9a169fcec4

rust/afdo.go

@@ -0,0 +1,48 @@
+// Copyright 2022 The Android Open Source Project
+//
+// 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 rust
+
+import (
+	"fmt"
+
+	"android/soong/cc"
+)
+
+const afdoFlagFormat = "-Zprofile-sample-use=%s"
+
+type afdo struct {
+	Properties cc.AfdoProperties
+}
+
+func (afdo *afdo) props() []interface{} {
+	return []interface{}{&afdo.Properties}
+}
+
+func (afdo *afdo) flags(ctx ModuleContext, flags Flags, deps PathDeps) (Flags, PathDeps) {
+	if ctx.Host() {
+		return flags, deps
+	}
+
+	if afdo != nil && afdo.Properties.Afdo {
+		if profileFile := afdo.Properties.GetAfdoProfileFile(ctx, ctx.ModuleName()); profileFile.Valid() {
+			profileUseFlag := fmt.Sprintf(afdoFlagFormat, profileFile)
+			flags.RustFlags = append(flags.RustFlags, profileUseFlag)
+
+			profileFilePath := profileFile.Path()
+			deps.AfdoProfiles = append(deps.AfdoProfiles, profileFilePath)
+		}
+	}
+	return flags, deps
+}