r264783 - [PGO] Move the instrumentation point closer to the value site.

[Betul Buyukkurt via cfe-commits]

Author: betulb
Date: Tue Mar 29 15:44:09 2016
New Revision: 264783

URL: http://llvm.org/viewvc/llvm-project?rev=264783&view=rev
Log:
[PGO] Move the instrumentation point closer to the value site.

For terminator instructions, the value profiling instrumentation
happens in a basic block other than where the value site resides.
This CR moves the instrumentation point prior to the value site.
Mostly NFC.


Added:
    cfe/trunk/test/Profile/cxx-indirect-call.cpp
Modified:
    cfe/trunk/lib/CodeGen/CodeGenPGO.cpp
    cfe/trunk/test/Profile/c-indirect-call.c

Modified: cfe/trunk/lib/CodeGen/CodeGenPGO.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/lib/CodeGen/CodeGenPGO.cpp?rev=264783&r1=264782&r2=264783&view=diff
==============================================================================
--- cfe/trunk/lib/CodeGen/CodeGenPGO.cpp (original)
+++ cfe/trunk/lib/CodeGen/CodeGenPGO.cpp Tue Mar 29 15:44:09 2016
@@ -757,10 +757,10 @@ void CodeGenPGO::valueProfile(CGBuilderT
 
   bool InstrumentValueSites = CGM.getCodeGenOpts().hasProfileClangInstr();
   if (InstrumentValueSites && RegionCounterMap) {
-    llvm::LLVMContext &Ctx = CGM.getLLVMContext();
-    auto *I8PtrTy = llvm::Type::getInt8PtrTy(Ctx);
+    auto BuilderInsertPoint = Builder.saveIP();
+    Builder.SetInsertPoint(ValueSite);
     llvm::Value *Args[5] = {
-        llvm::ConstantExpr::getBitCast(FuncNameVar, I8PtrTy),
+        llvm::ConstantExpr::getBitCast(FuncNameVar, Builder.getInt8PtrTy()),
         Builder.getInt64(FunctionHash),
         Builder.CreatePtrToInt(ValuePtr, Builder.getInt64Ty()),
         Builder.getInt32(ValueKind),
@@ -768,6 +768,7 @@ void CodeGenPGO::valueProfile(CGBuilderT
     };
     Builder.CreateCall(
         CGM.getIntrinsic(llvm::Intrinsic::instrprof_value_profile), Args);
+    Builder.restoreIP(BuilderInsertPoint);
     return;
   }
 

Modified: cfe/trunk/test/Profile/c-indirect-call.c
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Profile/c-indirect-call.c?rev=264783&r1=264782&r2=264783&view=diff
==============================================================================
--- cfe/trunk/test/Profile/c-indirect-call.c (original)
+++ cfe/trunk/test/Profile/c-indirect-call.c Tue Mar 29 15:44:09 2016
@@ -1,13 +1,14 @@
-// Check the data structures emitted by instrumentation.
+// Check the value profiling instrinsics emitted by instrumentation.
+
 // RUN: %clang_cc1 -triple x86_64-apple-macosx10.9 -main-file-name c-indirect-call.c %s -o - -emit-llvm -fprofile-instrument=clang -mllvm -enable-value-profiling | FileCheck %s
 
 void (*foo)(void);
 
 int main(void) {
 // CHECK:  [[REG1:%[0-9]+]] = load void ()*, void ()** @foo, align 8
-// CHECK-NEXT:  call void [[REG1]]()
 // CHECK-NEXT:  [[REG2:%[0-9]+]] = ptrtoint void ()* [[REG1]] to i64
 // CHECK-NEXT:  call void @__llvm_profile_instrument_target(i64 [[REG2]], i8* bitcast ({{.*}}* @__profd_main to i8*), i32 0)
+// CHECK-NEXT:  call void [[REG1]]()
   foo();
   return 0;
 }

Added: cfe/trunk/test/Profile/cxx-indirect-call.cpp
URL: http://llvm.org/viewvc/llvm-project/cfe/trunk/test/Profile/cxx-indirect-call.cpp?rev=264783&view=auto
==============================================================================
--- cfe/trunk/test/Profile/cxx-indirect-call.cpp (added)
+++ cfe/trunk/test/Profile/cxx-indirect-call.cpp Tue Mar 29 15:44:09 2016
@@ -0,0 +1,21 @@
+// Check the value profiling instrinsics emitted by instrumentation.
+
+// RUN: %clangxx %s -o - -emit-llvm -S -fprofile-instr-generate -mllvm -enable-value-profiling -fexceptions -target %itanium_abi_triple | FileCheck %s
+
+void (*foo) (void);
+
+int main(int argc, const char *argv[]) {
+// CHECK:  [[REG1:%[0-9]+]] = load void ()*, void ()** @foo, align 4
+// CHECK-NEXT:  [[REG2:%[0-9]+]] = ptrtoint void ()* [[REG1]] to i64
+// CHECK-NEXT:  call void @__llvm_profile_instrument_target(i64 [[REG2]], i8* bitcast ({{.*}}* @__profd_main to i8*), i32 0)
+// CHECK-NEXT:  invoke void [[REG1]]()
+  try {
+    foo();
+  } catch (int) {}
+  return 0;
+}
+
+// CHECK: declare void @__llvm_profile_instrument_target(i64, i8*, i32)
+
+
+