[PGO] Prohibit address recording if the function is both internal and COMDAT

Differential Revision: http://reviews.llvm.org/D19515

llvm-svn: 267792

2 files changed, 30 insertions, 0 deletions

diff --git a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
index b1f8a4ac70d..397e64b410e 100644
--- a/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
+++ b/llvm/lib/Transforms/Instrumentation/InstrProfiling.cpp
@@ -237,6 +237,11 @@ static inline bool shouldRecordFunctionAddr(Function *F) {
   if (!F->hasLinkOnceLinkage() && !F->hasLocalLinkage() &&
       !F->hasAvailableExternallyLinkage())
     return true;
+  // Prohibit function address recording if the function is both internal and
+  // COMDAT. This avoids the profile data variable referencing internal symbols
+  // in COMDAT.
+  if (F->hasLocalLinkage() && F->hasComdat())
+    return false;
   // Check uses of this function for other than direct calls or invokes to it.
   return F->hasAddressTaken();
 }
diff --git a/llvm/test/Transforms/PGOProfile/comdat_internal.ll b/llvm/test/Transforms/PGOProfile/comdat_internal.ll
new file mode 100644
index 00000000000..f6d2f31816f
--- /dev/null
+++ b/llvm/test/Transforms/PGOProfile/comdat_internal.ll
@@ -0,0 +1,25 @@
+; RUN: opt < %s -pgo-instr-gen -instrprof -S | FileCheck %s
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+$foo = comdat any
+
+; CHECK: $__llvm_profile_raw_version = comdat any
+; CHECK: $__profv__stdin__foo = comdat any
+
+@bar = global i32 ()* @foo, align 8
+
+; CHECK: @__llvm_profile_raw_version = constant i64 {{[0-9]+}}, comdat
+; CHECK: @__profn__stdin__foo = private constant [11 x i8] c"<stdin>:foo"
+; CHECK: @__profc__stdin__foo = private global [1 x i64] zeroinitializer, section "__llvm_prf_cnts", comdat($__profv__stdin__foo), align 8
+; CHECK: @__profd__stdin__foo = private global { i64, i64, i64*, i8*, i8*, i32, [1 x i16] } { i64 -5640069336071256030, i64 12884901887, i64* getelementptr inbounds ([1 x i64], [1 x i64]* @__profc__stdin__foo, i32 0, i32 0), i8*
+; CHECK-NOT: bitcast (i32 ()* @foo to i8*)
+; CHECK-SAME: null
+; CHECK-SAME: , i8* null, i32 1, [1 x i16] zeroinitializer }, section "__llvm_prf_data", comdat($__profv__stdin__foo), align 8
+; CHECK: @__llvm_prf_nm = private constant [21 x i8] c"\0B\13x\DA\B3).I\C9\CC\B3\B3J\CB\CF\07\00\18a\04\1B", section "__llvm_prf_names"
+; CHECK: @llvm.used = appending global [2 x i8*] [i8* bitcast ({ i64, i64, i64*, i8*, i8*, i32, [1 x i16] }* @__profd__stdin__foo to i8*), i8* getelementptr inbounds ([21 x i8], [21 x i8]* @__llvm_prf_nm, i32 0, i32 0)], section "llvm.metadata"
+
+define internal i32 @foo() comdat {
+entry:
+  ret i32 1
+}