Roll r123609 back in with two changes that fix test failures with expensive

checks enabled:

1) Use '<' to compare integers in a comparison function rather than '<='.

2) Use the uniqued set DefBlocks rather than Info.DefiningBlocks to initialize
the priority queue.

The speedup of scalarrepl on test-suite + SPEC2000 + SPEC2006 is a bit less, at
just under 16% rather than 17%.

llvm-svn: 123662

1 files changed, 1 insertions, 4 deletions

diff --git a/llvm/lib/Transforms/Utils/Mem2Reg.cpp b/llvm/lib/Transforms/Utils/Mem2Reg.cpp
index 2b1364c81e7..ea2f8fca5f2 100644
--- a/llvm/lib/Transforms/Utils/Mem2Reg.cpp
+++ b/llvm/lib/Transforms/Utils/Mem2Reg.cpp
@@ -40,7 +40,6 @@ namespace {
     //
     virtual void getAnalysisUsage(AnalysisUsage &AU) const {
       AU.addRequired<DominatorTree>();
-      AU.addRequired<DominanceFrontier>();
       AU.setPreservesCFG();
       // This is a cluster of orthogonal Transforms
       AU.addPreserved<UnifyFunctionExitNodes>();
@@ -54,7 +53,6 @@ char PromotePass::ID = 0;
 INITIALIZE_PASS_BEGIN(PromotePass, "mem2reg", "Promote Memory to Register",
                 false, false)
 INITIALIZE_PASS_DEPENDENCY(DominatorTree)
-INITIALIZE_PASS_DEPENDENCY(DominanceFrontier)
 INITIALIZE_PASS_END(PromotePass, "mem2reg", "Promote Memory to Register",
                 false, false)
 
@@ -66,7 +64,6 @@ bool PromotePass::runOnFunction(Function &F) {
   bool Changed  = false;
 
   DominatorTree &DT = getAnalysis<DominatorTree>();
-  DominanceFrontier &DF = getAnalysis<DominanceFrontier>();
 
   while (1) {
     Allocas.clear();
@@ -80,7 +77,7 @@ bool PromotePass::runOnFunction(Function &F) {
 
     if (Allocas.empty()) break;
 
-    PromoteMemToReg(Allocas, DT, DF);
+    PromoteMemToReg(Allocas, DT);
     NumPromoted += Allocas.size();
     Changed = true;
   }