Use more caching when computing non-local dependence. This makes bzip2 not

use up the entire 32-bit address space.

llvm-svn: 40596

2 files changed, 5 insertions, 1 deletions

diff --git a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
index 4bd877142a2..02b0af6f0f9 100644
--- a/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
+++ b/llvm/lib/Analysis/MemoryDependenceAnalysis.cpp
@@ -129,6 +129,8 @@ bool MemoryDependenceAnalysis::nonLocalHelper(Instruction* query,
 
   if (!inserted && !predOnStack)
     resp.insert(std::make_pair(block, None));
+  else if (inserted && predOnStack)
+    resp.insert(std::make_pair(block, NonLocal));
   
   return inserted;
 }
diff --git a/llvm/lib/Transforms/Scalar/GVN.cpp b/llvm/lib/Transforms/Scalar/GVN.cpp
index ab6c913605e..fee0eedcc77 100644
--- a/llvm/lib/Transforms/Scalar/GVN.cpp
+++ b/llvm/lib/Transforms/Scalar/GVN.cpp
@@ -752,7 +752,9 @@ bool GVN::processNonLocalLoad(LoadInst* L, SmallVector<Instruction*, 4>& toErase
        I != E; ++I)
     if (I->second == MemoryDependenceAnalysis::None) {
       return false;
-    } else if (StoreInst* S = dyn_cast<StoreInst>(I->second)) {
+    } else if (I->second == MemoryDependenceAnalysis::NonLocal) {
+      continue;
+    }else if (StoreInst* S = dyn_cast<StoreInst>(I->second)) {
       if (S->getPointerOperand() == L->getPointerOperand())
         repl.insert(std::make_pair(I->first, S->getOperand(0)));
       else