Revert "Remove fdoProfileMutator"

Revert submission 2925209

Reason for revert: b/323975183

Reverted changes: /q/submissionid:2925209

Change-Id: I33b2e71ba7b36e12e5c491e0ad14a7f7df3edd78
diff --git a/cc/afdo.go b/cc/afdo.go
index 0de1d4b..6155084 100644
--- a/cc/afdo.go
+++ b/cc/afdo.go
@@ -21,6 +21,7 @@
 	"android/soong/android"
 
 	"github.com/google/blueprint"
+	"github.com/google/blueprint/proptools"
 )
 
 // This flag needs to be in both CFlags and LdFlags to ensure correct symbol ordering
@@ -31,7 +32,7 @@
 	// automatic feedback-directed optimization using profile data.
 	Afdo bool
 
-	AfdoDep bool `blueprint:"mutated"`
+	FdoProfilePath *string `blueprint:"mutated"`
 }
 
 type afdo struct {
@@ -56,7 +57,7 @@
 }
 
 func (afdo *afdo) flags(ctx ModuleContext, flags Flags) Flags {
-	if afdo.Properties.Afdo || afdo.Properties.AfdoDep {
+	if afdo.Properties.Afdo {
 		// We use `-funique-internal-linkage-names` to associate profiles to the right internal
 		// functions. This option should be used before generating a profile. Because a profile
 		// generated for a binary without unique names doesn't work well building a binary with
@@ -74,39 +75,61 @@
 		// TODO(b/266595187): Remove the following feature once it is enabled in LLVM by default.
 		flags.Local.CFlags = append([]string{"-mllvm", "-improved-fs-discriminator=true"}, flags.Local.CFlags...)
 	}
-	fdoProfileDeps := ctx.GetDirectDepsWithTag(FdoProfileTag)
-	if len(fdoProfileDeps) > 0 && fdoProfileDeps[0] != nil {
-		if info, ok := android.OtherModuleProvider(ctx, fdoProfileDeps[0], FdoProfileProvider); ok {
-			fdoProfilePath := info.Path.String()
+	if path := afdo.Properties.FdoProfilePath; path != nil {
+		// The flags are prepended to allow overriding.
+		profileUseFlag := fmt.Sprintf(afdoFlagsFormat, *path)
+		flags.Local.CFlags = append([]string{profileUseFlag}, flags.Local.CFlags...)
+		flags.Local.LdFlags = append([]string{profileUseFlag, "-Wl,-mllvm,-no-warn-sample-unused=true"}, flags.Local.LdFlags...)
 
-			// The flags are prepended to allow overriding.
-			profileUseFlag := fmt.Sprintf(afdoFlagsFormat, fdoProfilePath)
-			flags.Local.CFlags = append([]string{profileUseFlag}, flags.Local.CFlags...)
-			flags.Local.LdFlags = append([]string{profileUseFlag, "-Wl,-mllvm,-no-warn-sample-unused=true"}, flags.Local.LdFlags...)
-
-			// Update CFlagsDeps and LdFlagsDeps so the module is rebuilt
-			// if profileFile gets updated
-			pathForSrc := android.PathForSource(ctx, fdoProfilePath)
-			flags.CFlagsDeps = append(flags.CFlagsDeps, pathForSrc)
-			flags.LdFlagsDeps = append(flags.LdFlagsDeps, pathForSrc)
-		}
+		// Update CFlagsDeps and LdFlagsDeps so the module is rebuilt
+		// if profileFile gets updated
+		pathForSrc := android.PathForSource(ctx, *path)
+		flags.CFlagsDeps = append(flags.CFlagsDeps, pathForSrc)
+		flags.LdFlagsDeps = append(flags.LdFlagsDeps, pathForSrc)
 	}
 
 	return flags
 }
 
-func (a *afdo) addDep(ctx android.BottomUpMutatorContext, fdoProfileTarget string) {
-	if fdoProfileName, err := ctx.DeviceConfig().AfdoProfile(fdoProfileTarget); fdoProfileName != "" && err == nil {
-		ctx.AddFarVariationDependencies(
-			[]blueprint.Variation{
-				{Mutator: "arch", Variation: ctx.Target().ArchVariation()},
-				{Mutator: "os", Variation: "android"},
-			},
-			FdoProfileTag,
-			fdoProfileName)
+// FdoProfileMutator reads the FdoProfileProvider from a direct dep with FdoProfileTag
+// assigns FdoProfileInfo.Path to the FdoProfilePath mutated property
+func (c *Module) fdoProfileMutator(ctx android.BottomUpMutatorContext) {
+	if !c.Enabled() {
+		return
+	}
+
+	if !c.afdo.afdoEnabled() {
+		return
+	}
+
+	if c.Host() {
+		return
+	}
+
+	if c.static() && !c.staticBinary() {
+		return
+	}
+
+	if c, ok := ctx.Module().(*Module); ok && c.Enabled() {
+		if fdoProfileName, err := ctx.DeviceConfig().AfdoProfile(ctx.ModuleName()); fdoProfileName != "" && err == nil {
+			deps := ctx.AddFarVariationDependencies(
+				[]blueprint.Variation{
+					{Mutator: "arch", Variation: ctx.Target().ArchVariation()},
+					{Mutator: "os", Variation: "android"},
+				},
+				FdoProfileTag,
+				fdoProfileName)
+			if len(deps) > 0 && deps[0] != nil {
+				if info, ok := android.OtherModuleProvider(ctx, deps[0], FdoProfileProvider); ok {
+					c.afdo.Properties.FdoProfilePath = proptools.StringPtr(info.Path.String())
+				}
+			}
+		}
 	}
 }
 
+var _ FdoProfileMutatorInterface = (*Module)(nil)
+
 func afdoPropagateViaDepTag(tag blueprint.DependencyTag) bool {
 	libTag, isLibTag := tag.(libraryDependencyTag)
 	// Do not recurse down non-static dependencies
@@ -149,16 +172,27 @@
 }
 
 func (a *afdoTransitionMutator) Mutate(ctx android.BottomUpMutatorContext, variation string) {
+	if variation == "" {
+		return
+	}
+
 	if m, ok := ctx.Module().(*Module); ok && m.afdo != nil {
-		if variation == "" {
-			if m.afdo.afdoEnabled() && !(m.static() && !m.staticBinary()) && !m.Host() {
-				m.afdo.addDep(ctx, ctx.ModuleName())
+		m.Properties.PreventInstall = true
+		m.Properties.HideFromMake = true
+		m.afdo.Properties.Afdo = true
+		if fdoProfileName, err := ctx.DeviceConfig().AfdoProfile(decodeTarget(variation)); fdoProfileName != "" && err == nil {
+			deps := ctx.AddFarVariationDependencies(
+				[]blueprint.Variation{
+					{Mutator: "arch", Variation: ctx.Target().ArchVariation()},
+					{Mutator: "os", Variation: "android"},
+				},
+				FdoProfileTag,
+				fdoProfileName)
+			if len(deps) > 0 && deps[0] != nil {
+				if info, ok := android.OtherModuleProvider(ctx, deps[0], FdoProfileProvider); ok {
+					m.afdo.Properties.FdoProfilePath = proptools.StringPtr(info.Path.String())
+				}
 			}
-		} else {
-			m.Properties.PreventInstall = true
-			m.Properties.HideFromMake = true
-			m.afdo.Properties.AfdoDep = true
-			m.afdo.addDep(ctx, decodeTarget(variation))
 		}
 	}
 }