[PGO] Add PGO support at -O0 in the experimental new pass manager

Add PGO support at -O0 in the experimental new pass manager to sync the
behavior of the legacy pass manager.

Also change the test of gcc-flag-compatibility.c for more complete test:
(1) change the match string to "profc" and "profd" to ensure the
    instrumentation is happening.
(2) add IR format proftext so that PGO use compilation is tested.

Differential Revision: https://reviews.llvm.org/D64029

llvm-svn: 367628

1 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/CodeGen/BackendUtil.cpp b/clang/lib/CodeGen/BackendUtil.cpp
index 73eec01ee65..84552e27a4c 100644
--- a/clang/lib/CodeGen/BackendUtil.cpp
+++ b/clang/lib/CodeGen/BackendUtil.cpp
@@ -1117,6 +1117,16 @@ void EmitAssemblyHelper::EmitAssemblyWithNewPassManager(
       // code generation.
       MPM.addPass(AlwaysInlinerPass(/*InsertLifetimeIntrinsics=*/false));
 
+      // At -O0, we can still do PGO. Add all the requested passes for
+      // instrumentation PGO, if requested.
+      if (PGOOpt && (PGOOpt->Action == PGOOptions::IRInstr ||
+                     PGOOpt->Action == PGOOptions::IRUse))
+        PB.addPGOInstrPassesForO0(
+            MPM, CodeGenOpts.DebugPassManager,
+            /* RunProfileGen */ (PGOOpt->Action == PGOOptions::IRInstr),
+            /* IsCS */ false, PGOOpt->ProfileFile,
+            PGOOpt->ProfileRemappingFile);
+
       // At -O0 we directly run necessary sanitizer passes.
       if (LangOpts.Sanitize.has(SanitizerKind::LocalBounds))
         MPM.addPass(createModuleToFunctionPassAdaptor(BoundsCheckingPass()));