1 files changed, 74 insertions, 0 deletions
diff --git a/rust/coverage.go b/rust/coverage.go
new file mode 100644
index 000000000..dac526a36
--- /dev/null
+++ b/rust/coverage.go
@@ -0,0 +1,74 @@
+// Copyright 2020 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 (
+	"github.com/google/blueprint"
+
+	"android/soong/cc"
+)
+
+var CovLibraryName = "libprofile-clang-extras"
+
+const profileInstrFlag = "-fprofile-instr-generate=/data/misc/trace/clang-%p-%m.profraw"
+
+type coverage struct {
+	Properties cc.CoverageProperties
+
+	// Whether binaries containing this module need --coverage added to their ldflags
+	linkCoverage bool
+}
+
+func (cov *coverage) props() []interface{} {
+	return []interface{}{&cov.Properties}
+}
+
+func (cov *coverage) deps(ctx DepsContext, deps Deps) Deps {
+	if cov.Properties.NeedCoverageVariant {
+		ctx.AddVariationDependencies([]blueprint.Variation{
+			{Mutator: "link", Variation: "static"},
+		}, cc.CoverageDepTag, CovLibraryName)
+	}
+
+	return deps
+}
+
+func (cov *coverage) flags(ctx ModuleContext, flags Flags, deps PathDeps) (Flags, PathDeps) {
+
+	if !ctx.DeviceConfig().NativeCoverageEnabled() {
+		return flags, deps
+	}
+
+	if cov.Properties.CoverageEnabled {
+		flags.Coverage = true
+		coverage := ctx.GetDirectDepWithTag(CovLibraryName, cc.CoverageDepTag).(cc.LinkableInterface)
+		flags.RustFlags = append(flags.RustFlags,
+			"-Z instrument-coverage", "-g", "-C link-dead-code")
+		flags.LinkFlags = append(flags.LinkFlags,
+			profileInstrFlag, "-g", coverage.OutputFile().Path().String(), "-Wl,--wrap,open")
+		deps.StaticLibs = append(deps.StaticLibs, coverage.OutputFile().Path())
+	}
+
+	return flags, deps
+}
+
+func (cov *coverage) begin(ctx BaseModuleContext) {
+	if ctx.Host() {
+		// Host coverage not yet supported.
+	} else {
+		// Update useSdk and sdkVersion args if Rust modules become SDK aware.
+		cov.Properties = cc.SetCoverageProperties(ctx, cov.Properties, ctx.RustModule().nativeCoverage(), false, "")
+	}
+}