commit ada83ec0a6dc677cffd0d29c10b48cbda477daf7
author Pirama Arumuga Nainar <pirama@google.com> Thu Aug 31 23:38:27 2017 -0700
committer Pirama Arumuga Nainar <pirama@google.com> Thu Sep 21 12:37:19 2017 -0700
tree 5be48add3d9c89ce7c5b4e615642812f5aa7bb01
parent d685385c6baf385c1d87bfa92dcd0f824a2cb09f

Add PGO support to soong

Bug: http://b/63768402
Bug: http://b/65598278

Add support for the 'pgo' property to specify how a module is processed
under PGO.  A sample property is below:

pgo: {
    instrumentation: true, // could be "sampling: true" when supported
    profile_file: "pgo_simple.profdata",
    benchmarks: ["pgo_simple"],
}

1. Runtime profiles can be gathered using "sampling" or
"instrumentation".  Sampling is not supported initially.

2. If 'toolchain/pgo-profiles' project is found,
'toolchain/pgo-profiles/${profile_file}' is passed to the compiler and
linker when building this module.

3. If ANDROID_PGO_INSTRUMENT environment variable is set, and includes a
benchmark in the 'benchmarks' list, appropriate flags (for e.g.
-fprofile-generate for instrumentation) are passed to the compiler and
linker when building this module.

Test: Add example modules that specify the pgo property and verify
appropriate flags and dependencies in the Ninja file.  Some
tests/examples are in https://android-review.googlesource.com/474805

Change-Id: I6242e0c904497a115e367dea6927ba1c4b906355

cc/cc.go

diff --git a/cc/cc.go b/cc/cc.go
index af58f9d..b4b70ed 100644
--- a/cc/cc.go
+++ b/cc/cc.go
@@ -134,7 +134,8 @@
 	RequiredInstructionSet string
 	DynamicLinker          string
 
-	CFlagsDeps android.Paths // Files depended on by compiler flags
+	CFlagsDeps  android.Paths // Files depended on by compiler flags
+	LdFlagsDeps android.Paths // Files depended on by linker flags
 
 	GroupStaticLibs bool
 }
@@ -308,6 +309,7 @@
 	sabi      *sabi
 	vndkdep   *vndkdep
 	lto       *lto
+	pgo       *pgo
 
 	androidMkSharedLibDeps []string
 
@@ -350,6 +352,9 @@
 	if c.lto != nil {
 		c.AddProperties(c.lto.props()...)
 	}
+	if c.pgo != nil {
+		c.AddProperties(c.pgo.props()...)
+	}
 	for _, feature := range c.features {
 		c.AddProperties(feature.props()...)
 	}
@@ -506,6 +511,7 @@
 	module.sabi = &sabi{}
 	module.vndkdep = &vndkdep{}
 	module.lto = &lto{}
+	module.pgo = &pgo{}
 	return module
 }
 
@@ -557,6 +563,9 @@
 	if c.lto != nil {
 		flags = c.lto.flags(ctx, flags)
 	}
+	if c.pgo != nil {
+		flags = c.pgo.flags(ctx, flags)
+	}
 	for _, feature := range c.features {
 		flags = feature.flags(ctx, flags)
 	}
@@ -643,6 +652,9 @@
 	if c.lto != nil {
 		c.lto.begin(ctx)
 	}
+	if c.pgo != nil {
+		c.pgo.begin(ctx)
+	}
 	for _, feature := range c.features {
 		feature.begin(ctx)
 	}
@@ -1250,6 +1262,7 @@
 		&SAbiProperties{},
 		&VndkProperties{},
 		&LTOProperties{},
+		&PgoProperties{},
 	)
 
 	android.InitDefaultsModule(module)