[ThinLTO] Add option to dump value name to GUID mapping

Summary:
Useful for debugging since we lose this correlation after the permodule
summary/VST is read and until we later materialize source modules in the
function importer.

Reviewers: joker.eph

Subscribers: llvm-commits, joker.eph

Differential Revision: http://reviews.llvm.org/D18555

llvm-svn: 265327

1 files changed, 17 insertions, 5 deletions

diff --git a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
index e784c88..09e5220 100644
--- a/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
+++ b/llvm/lib/Bitcode/Reader/BitcodeReader.cpp
@@ -29,7 +29,9 @@
 #include "llvm/IR/OperandTraits.h"
 #include "llvm/IR/Operator.h"
 #include "llvm/IR/ValueHandle.h"
+#include "llvm/Support/CommandLine.h"
 #include "llvm/Support/DataStream.h"
+#include "llvm/Support/Debug.h"
 #include "llvm/Support/ManagedStatic.h"
 #include "llvm/Support/MathExtras.h"
 #include "llvm/Support/MemoryBuffer.h"
@@ -38,6 +40,11 @@
 
 using namespace llvm;
 
+static cl::opt<bool> PrintSummaryGUIDs(
+    "print-summary-global-ids", cl::init(false), cl::Hidden,
+    cl::desc(
+        "Print the global id for each value when reading the module summary"));
+
 namespace {
 enum {
   SWITCH_INST_MAGIC = 0x4B5 // May 2012 => 1205 => Hex
@@ -5520,8 +5527,11 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseValueSymbolTable(
              "No linkage found for VST entry?");
       std::string GlobalId = GlobalValue::getGlobalIdentifier(
           ValueName, VLI->second, SourceFileName);
-      TheIndex->addGlobalValueInfo(GlobalId, std::move(GlobalValInfo));
-      ValueIdToCallGraphGUIDMap[ValueID] = GlobalValue::getGUID(GlobalId);
+      auto ValueGUID = GlobalValue::getGUID(GlobalId);
+      if (PrintSummaryGUIDs)
+        dbgs() << "GUID " << ValueGUID << " is " << ValueName << "\n";
+      TheIndex->addGlobalValueInfo(ValueGUID, std::move(GlobalValInfo));
+      ValueIdToCallGraphGUIDMap[ValueID] = ValueGUID;
       ValueName.clear();
       break;
     }
@@ -5540,9 +5550,11 @@ std::error_code ModuleSummaryIndexBitcodeReader::parseValueSymbolTable(
              "No linkage found for VST entry?");
       std::string FunctionGlobalId = GlobalValue::getGlobalIdentifier(
           ValueName, VLI->second, SourceFileName);
-      TheIndex->addGlobalValueInfo(FunctionGlobalId, std::move(FuncInfo));
-      ValueIdToCallGraphGUIDMap[ValueID] =
-          GlobalValue::getGUID(FunctionGlobalId);
+      auto FunctionGUID = GlobalValue::getGUID(FunctionGlobalId);
+      if (PrintSummaryGUIDs)
+        dbgs() << "GUID " << FunctionGUID << " is " << ValueName << "\n";
+      TheIndex->addGlobalValueInfo(FunctionGUID, std::move(FuncInfo));
+      ValueIdToCallGraphGUIDMap[ValueID] = FunctionGUID;
 
       ValueName.clear();
       break;