[PGO] More comments how function pointers for indirect calls are mapped

to function names

Summary:
Hopefully this will make it easier for the next person to figure all
this out...

Reviewers: bogner, davidxl

Subscribers: davidxl, cfe-commits

Differential Revision: http://reviews.llvm.org/D18489

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@264681 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/CodeGen/CGCall.cpp b/lib/CodeGen/CGCall.cpp
index 5e10f26ceb6923211d44f0674a7a873f696bf49c..0693949e4366ee6f340669d7ccdcf08f74717046 100644 (file)
--- a/lib/CodeGen/CGCall.cpp
+++ b/lib/CodeGen/CGCall.cpp
@@ -3817,7 +3817,9 @@ RValue CodeGenFunction::EmitCall(const CGFunctionInfo &CallInfo,
   CS.setAttributes(Attrs);
   CS.setCallingConv(static_cast<llvm::CallingConv::ID>(CallingConv));
 
-  // Insert instrumentation or attach profile metadata at indirect call sites
+  // Insert instrumentation or attach profile metadata at indirect call sites.
+  // For more details, see the comment before the definition of
+  // IPVK_IndirectCallTarget in InstrProfData.inc.
   if (!CS.getCalledFunction())
     PGO.valueProfile(Builder, llvm::IPVK_IndirectCallTarget,
                      CS.getInstruction(), Callee);