Simplify CFG before assigning discriminator.

Summary: We need to clean up CFG before assigning discriminator to minimize the impact of optimization on debug info.

Reviewers: davidxl, dblaikie, dnovillo

Subscribers: dnovillo, danielcdh, llvm-commits

Differential Revision: http://reviews.llvm.org/D19926

llvm-svn: 268675

2 files changed, 30 insertions, 28 deletions

diff --git a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
index e6933336947..97c5f183dcb 100644
--- a/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
+++ b/llvm/lib/Transforms/Scalar/SimplifyCFGPass.cpp
@@ -196,35 +196,31 @@ PreservedAnalyses SimplifyCFGPass::run(Function &F,
   return PreservedAnalyses::all();
 }
 
-namespace {
-struct CFGSimplifyPass : public FunctionPass {
-  static char ID; // Pass identification, replacement for typeid
-  unsigned BonusInstThreshold;
-  std::function<bool(const Function &)> PredicateFtor;
-
-  CFGSimplifyPass(int T = -1,
-                  std::function<bool(const Function &)> Ftor = nullptr)
-      : FunctionPass(ID), PredicateFtor(Ftor) {
-    BonusInstThreshold = (T == -1) ? UserBonusInstThreshold : unsigned(T);
-    initializeCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
-  }
-  bool runOnFunction(Function &F) override {
-    if (skipFunction(F) || (PredicateFtor && !PredicateFtor(F)))
-      return false;
-
-    AssumptionCache *AC =
-        &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
-    const TargetTransformInfo &TTI =
-        getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
-    return simplifyFunctionCFG(F, TTI, AC, BonusInstThreshold);
-  }
+CFGSimplifyPass::CFGSimplifyPass(int T,
+            std::function<bool(const Function &)> Ftor)
+    : FunctionPass(ID), PredicateFtor(Ftor) {
+  BonusInstThreshold = (T == -1) ? UserBonusInstThreshold : unsigned(T);
+  initializeCFGSimplifyPassPass(*PassRegistry::getPassRegistry());
+}
 
-  void getAnalysisUsage(AnalysisUsage &AU) const override {
-    AU.addRequired<AssumptionCacheTracker>();
-    AU.addRequired<TargetTransformInfoWrapperPass>();
-    AU.addPreserved<GlobalsAAWrapperPass>();
-  }
-};
+bool CFGSimplifyPass::runOnFunction(Function &F) {
+  if (PredicateFtor && !PredicateFtor(F))
+    return false;
+
+  if (skipFunction(F))
+    return false;
+
+  AssumptionCache *AC =
+      &getAnalysis<AssumptionCacheTracker>().getAssumptionCache(F);
+  const TargetTransformInfo &TTI =
+      getAnalysis<TargetTransformInfoWrapperPass>().getTTI(F);
+  return simplifyFunctionCFG(F, TTI, AC, BonusInstThreshold);
+}
+
+void CFGSimplifyPass::getAnalysisUsage(AnalysisUsage &AU) const {
+  AU.addRequired<AssumptionCacheTracker>();
+  AU.addRequired<TargetTransformInfoWrapperPass>();
+  AU.addPreserved<GlobalsAAWrapperPass>();
 }
 
 char CFGSimplifyPass::ID = 0;
diff --git a/llvm/lib/Transforms/Utils/AddDiscriminators.cpp b/llvm/lib/Transforms/Utils/AddDiscriminators.cpp
index 2a6b6eb1b0b..6c4db99efe3 100644
--- a/llvm/lib/Transforms/Utils/AddDiscriminators.cpp
+++ b/llvm/lib/Transforms/Utils/AddDiscriminators.cpp
@@ -67,6 +67,7 @@
 #include "llvm/Support/Debug.h"
 #include "llvm/Support/raw_ostream.h"
 #include "llvm/Transforms/Scalar.h"
+#include "llvm/Transforms/Scalar/SimplifyCFG.h"
 
 using namespace llvm;
 
@@ -79,6 +80,10 @@ struct AddDiscriminators : public FunctionPass {
     initializeAddDiscriminatorsPass(*PassRegistry::getPassRegistry());
   }
 
+  void getAnalysisUsage(AnalysisUsage &AU) const override {
+    AU.addRequired<CFGSimplifyPass>();
+  }
+
   bool runOnFunction(Function &F) override;
 };
 } // end anonymous namespace
@@ -86,6 +91,7 @@ struct AddDiscriminators : public FunctionPass {
 char AddDiscriminators::ID = 0;
 INITIALIZE_PASS_BEGIN(AddDiscriminators, "add-discriminators",
                       "Add DWARF path discriminators", false, false)
+INITIALIZE_PASS_DEPENDENCY(CFGSimplifyPass)
 INITIALIZE_PASS_END(AddDiscriminators, "add-discriminators",
                     "Add DWARF path discriminators", false, false)