Bug: http://b/65598278
This property defaults to 'true' and setting it to false skips profile
use. This escape hatch lets us disable PGO for a module without
completely removing the 'pgo' property. Additionally, this also helps
selectively disabling PGO for some architectures, if desired.
Test: Test that -fprofile-use is not added for a test module if
'enable_profile_use: false' is set.
Change-Id: Ifcf1a48c194bc86efd88a529cc2d66a47b7ab080
Bug: http://b/65598278
Non-PGO builds (with this environment variable set) can be used to
measure the performance difference induced by PGO.
Test: Build PGO modules with ANDROID_PGO_PROFILE_USE set.
Change-Id: Ib23bad5208ac7f54894c7768d7532f53b6b91179
These methods only need the 'PgoProperties' struct. Avoid the extra
indirection by directly using this struct.
Test: Build modules with PGO property.
Change-Id: I1923ebde4b0d546810de8e696514d218b3a4f54b
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>
Bug: http://b/63768402
Wno-backend-plugin warnings are generated by IR-based PGO when sources
evolve and the profiles become stale. Disable these warnings when
profiles are passed to the compiler.
Test: Build a module with a PGO property when profiles are used.
Change-Id: I462bbf55aafd8770a90c2c23462bf71607ac9108
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
