Explicitly link the profile runtime during PGO
Bug: http://b/65598278
The profile runtime depends on libgcc for some symbols (only under some
circumstances - armv5, ndk r14, static executables). Since Android
build passes -nostdlib and adds libgcc manually, the profile runtime
gets passed to the linker later than libgcc.
Instead, explicitly add the profile runtime to the linker command (and
pass one other flag added by the clang driver to the link).
Test: Build a library with profile instrumentation that otherwise fails
instrumented build.
Change-Id: I24b34cebd2c3bb6a540f8f4c465ace1be4eb90f3
Signed-off-by: Pirama Arumuga Nainar <pirama@google.com>
diff --git a/cc/cc.go b/cc/cc.go
index b4b70ed..4f10a11 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -673,6 +673,12 @@
if c.compiler != nil {
deps = c.compiler.compilerDeps(ctx, deps)
}
+ // Add the PGO dependency (the clang_rt.profile runtime library), which
+ // sometimes depends on symbols from libgcc, before libgcc gets added
+ // in linkerDeps().
+ if c.pgo != nil {
+ deps = c.pgo.deps(ctx, deps)
+ }
if c.linker != nil {
deps = c.linker.linkerDeps(ctx, deps)
}
diff --git a/cc/config/toolchain.go b/cc/config/toolchain.go
index d62ebe4..796ccfb 100644
--- a/cc/config/toolchain.go
+++ b/cc/config/toolchain.go
@@ -233,6 +233,10 @@
return SanitizerRuntimeLibrary(t, "tsan")
}
+func ProfileRuntimeLibrary(t Toolchain) string {
+ return SanitizerRuntimeLibrary(t, "profile")
+}
+
func ToolPath(t Toolchain) string {
if p := t.ToolPath(); p != "" {
return p
diff --git a/cc/pgo.go b/cc/pgo.go
index f9c8bbf..5d1c58a 100644
--- a/cc/pgo.go
+++ b/cc/pgo.go
@@ -19,6 +19,7 @@
"strings"
"android/soong/android"
+ "android/soong/cc/config"
)
var (
@@ -50,25 +51,38 @@
Properties PgoProperties
}
+func (props *PgoProperties) isInstrumentation() bool {
+ return props.Pgo.Instrumentation != nil && *props.Pgo.Instrumentation == true
+}
+
+func (props *PgoProperties) isSampling() bool {
+ return props.Pgo.Sampling != nil && *props.Pgo.Sampling == true
+}
+
func (pgo *pgo) props() []interface{} {
return []interface{}{&pgo.Properties}
}
-func (pgo *pgo) profileGatherFlags(ctx ModuleContext) string {
- if *pgo.Properties.Pgo.Instrumentation {
- return profileInstrumentFlag
+func (pgo *pgo) addProfileGatherFlags(ctx ModuleContext, flags Flags) Flags {
+ if pgo.Properties.isInstrumentation() {
+ flags.CFlags = append(flags.CFlags, profileInstrumentFlag)
+ // The profile runtime is added below in deps(). Add the below
+ // flag, which is the only other link-time action performed by
+ // the Clang driver during link.
+ flags.LdFlags = append(flags.LdFlags, "-u__llvm_profile_runtime")
}
- if *pgo.Properties.Pgo.Sampling {
- return profileSamplingFlag
+ if pgo.Properties.isSampling() {
+ flags.CFlags = append(flags.CFlags, profileSamplingFlag)
+ flags.LdFlags = append(flags.LdFlags, profileSamplingFlag)
}
- return ""
+ return flags
}
func (pgo *pgo) profileUseFlag(ctx ModuleContext, file string) string {
- if *pgo.Properties.Pgo.Instrumentation {
+ if pgo.Properties.isInstrumentation() {
return fmt.Sprintf(profileUseInstrumentFormat, file)
}
- if *pgo.Properties.Pgo.Sampling {
+ if pgo.Properties.isSampling() {
return fmt.Sprintf(profileUseSamplingFormat, file)
}
return ""
@@ -81,8 +95,8 @@
}
func (props *PgoProperties) isPGO(ctx BaseModuleContext) bool {
- isInstrumentation := props.Pgo.Instrumentation != nil
- isSampling := props.Pgo.Sampling != nil
+ isInstrumentation := props.isInstrumentation()
+ isSampling := props.isSampling()
profileKindPresent := isInstrumentation || isSampling
filePresent := props.Pgo.Profile_file != nil
@@ -156,6 +170,14 @@
}
}
+func (pgo *pgo) deps(ctx BaseModuleContext, deps Deps) Deps {
+ if pgo.Properties.ShouldProfileModule {
+ runtimeLibrary := config.ProfileRuntimeLibrary(ctx.toolchain())
+ deps.LateStaticLibs = append(deps.LateStaticLibs, runtimeLibrary)
+ }
+ return deps
+}
+
func (pgo *pgo) flags(ctx ModuleContext, flags Flags) Flags {
if ctx.Host() {
return flags
@@ -165,10 +187,7 @@
// Add flags to profile this module based on its profile_kind
if props.ShouldProfileModule {
- profileGatherFlags := pgo.profileGatherFlags(ctx)
- flags.LdFlags = append(flags.LdFlags, profileGatherFlags)
- flags.CFlags = append(flags.CFlags, profileGatherFlags)
- return flags
+ return pgo.addProfileGatherFlags(ctx, flags)
}
// If the PGO profiles project is found, and this module has PGO