[PGO] Fix profile var comdat generation problem with COFF

When targeting COFF, it is required that a comdat section to
have a global obj with the same name as the comdat (except for
comdats with select kind to be associative). This fix makes
sure that the comdat is keyed on the data variable for COFF.

Also improved test coverage for this.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@256193 91177308-0d34-0410-b5e6-96231b3b80d8

2 files changed, 19 insertions, 2 deletions

diff --git a/lib/Transforms/Instrumentation/InstrProfiling.cpp b/lib/Transforms/Instrumentation/InstrProfiling.cpp
index 57ed2f784af..0c0b54fe689 100644
--- a/lib/Transforms/Instrumentation/InstrProfiling.cpp
+++ b/lib/Transforms/Instrumentation/InstrProfiling.cpp
@@ -279,6 +279,16 @@ static inline bool shouldRecordFunctionAddr(Function *F) {
   return F->hasAddressTaken();
 }
 
+static inline Comdat *getOrCreateProfileComdat(Module &M,
+                                               InstrProfIncrementInst *Inc) {
+  // COFF format requires a COMDAT section to have a key symbol with the same
+  // name.
+  StringRef ComdatPrefix = (Triple(M.getTargetTriple()).isOSBinFormatCOFF()
+                                ? getInstrProfDataVarPrefix()
+                                : getInstrProfComdatPrefix());
+  return M.getOrInsertComdat(StringRef(getVarName(Inc, ComdatPrefix)));
+}
+
 GlobalVariable *
 InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) {
   GlobalVariable *NamePtr = Inc->getName();
@@ -297,8 +307,7 @@ InstrProfiling::getOrCreateRegionCounters(InstrProfIncrementInst *Inc) {
   Function *Fn = Inc->getParent()->getParent();
   Comdat *ProfileVarsComdat = nullptr;
   if (Fn->hasComdat())
-    ProfileVarsComdat = M->getOrInsertComdat(
-        StringRef(getVarName(Inc, getInstrProfComdatPrefix())));
+    ProfileVarsComdat = getOrCreateProfileComdat(*M, Inc);
   NamePtr->setSection(getNameSection());
   NamePtr->setAlignment(1);
   NamePtr->setComdat(ProfileVarsComdat);
diff --git a/test/Instrumentation/InstrProfiling/PR23499.ll b/test/Instrumentation/InstrProfiling/PR23499.ll
index 9c128a5f422..e5284b526f3 100644
--- a/test/Instrumentation/InstrProfiling/PR23499.ll
+++ b/test/Instrumentation/InstrProfiling/PR23499.ll
@@ -3,6 +3,9 @@
 
 ; RUN: opt < %s -mtriple=x86_64-apple-macosx10.10.0 -instrprof -S | FileCheck %s
 ; RUN: opt < %s -mtriple=x86_64-unknown-linux -instrprof -S | FileCheck %s
+; RUN: opt < %s -mtriple=x86_64-pc-win64-coff -instrprof -S | FileCheck %s --check-prefix=COFF
+; RUN: opt < %s -mtriple=x86_64-unknown-linux -instrprof -S | llc -mtriple=x86_64-unknown-linux
+; RUN: opt < %s -mtriple=x86_64-pc-win64-coff -instrprof -S | llc -mtriple=x86_64-pc-win64-coff
 
 $_Z3barIvEvv = comdat any
 
@@ -12,6 +15,11 @@ $_Z3barIvEvv = comdat any
 ; CHECK: @__profc__Z3barIvEvv = linkonce_odr hidden global [1 x i64] zeroinitializer, section "{{.*}}__llvm_prf_cnts", comdat($__profv__Z3barIvEvv), align 8
 ; CHECK: @__profd__Z3barIvEvv = linkonce_odr hidden global { i32, i32, i64, i8*, i64*, i8*, i8*, [1 x i16] } { i32 11, i32 1, i64 0, i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__profn__Z3barIvEvv, i32 0, i32 0), i64* getelementptr inbounds ([1 x i64], [1 x i64]* @__profc__Z3barIvEvv, i32 0, i32 0), i8* null, i8* null, [1 x i16] zeroinitializer }, section "{{.*}}__llvm_prf_data", comdat($__profv__Z3barIvEvv), align 8
 
+; COFF: @__profn__Z3barIvEvv = linkonce_odr hidden constant [11 x i8] c"_Z3barIvEvv", section "{{.*}}__llvm_prf_names", comdat($__profd__Z3barIvEvv), align 1
+; COFF: @__profc__Z3barIvEvv = linkonce_odr hidden global [1 x i64] zeroinitializer, section "{{.*}}__llvm_prf_cnts", comdat($__profd__Z3barIvEvv), align 8
+; COFF: @__profd__Z3barIvEvv = linkonce_odr hidden global { i32, i32, i64, i8*, i64*, i8*, i8*, [1 x i16] } { i32 11, i32 1, i64 0, i8* getelementptr inbounds ([11 x i8], [11 x i8]* @__profn__Z3barIvEvv, i32 0, i32 0), i64* getelementptr inbounds ([1 x i64], [1 x i64]* @__profc__Z3barIvEvv, i32 0, i32 0), i8* null, i8* null, [1 x i16] zeroinitializer }, section "{{.*}}__llvm_prf_data", comdat, align 8
+
+
 declare void @llvm.instrprof.increment(i8*, i64, i32, i32) #1
 
 define linkonce_odr void @_Z3barIvEvv() comdat {