While folding unconditional return move DbgRegionEndInst into the predecessor, instea...

[oota-llvm.git] / lib / Transforms / Utils / PromoteMemoryToRegister.cpp

diff --git a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
index 2c1ad10517b371566a78cd1e754eef002598b240..cc626ae71f5c653157abc788b129293efad249ce 100644 (file)
--- a/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
+++ b/lib/Transforms/Utils/PromoteMemoryToRegister.cpp
@@ -22,6 +22,7 @@
 #include "llvm/DerivedTypes.h"
 #include "llvm/Function.h"
 #include "llvm/Instructions.h"
+#include "llvm/IntrinsicInst.h"
 #include "llvm/Analysis/Dominators.h"
 #include "llvm/Analysis/AliasSetTracker.h"
 #include "llvm/ADT/DenseMap.h"
@@ -29,6 +30,7 @@
 #include "llvm/ADT/SmallVector.h"
 #include "llvm/ADT/Statistic.h"
 #include "llvm/ADT/StringExtras.h"
+#include "llvm/ADT/STLExtras.h"
 #include "llvm/Support/CFG.h"
 #include "llvm/Support/Compiler.h"
 #include <algorithm>
@@ -78,8 +80,12 @@ bool llvm::isAllocaPromotable(const AllocaInst *AI) {
         return false;   // Don't allow a store OF the AI, only INTO the AI.
       if (SI->isVolatile())
         return false;
+    } else if (const BitCastInst *BC = dyn_cast<BitCastInst>(*UI)) {
+      // Uses by dbg info shouldn't inhibit promotion.
+      if (!BC->hasOneUse() || !isa<DbgInfoIntrinsic>(*BC->use_begin()))
+        return false;
     } else {
-      return false;   // Not a load or store.
+      return false;
     }
 
   return true;
@@ -275,14 +281,23 @@ namespace {
     /// ivars.
     void AnalyzeAlloca(AllocaInst *AI) {
       clear();
-      
+
       // As we scan the uses of the alloca instruction, keep track of stores,
       // and decide whether all of the loads and stores to the alloca are within
       // the same basic block.
       for (Value::use_iterator U = AI->use_begin(), E = AI->use_end();
-           U != E; ++U) {
+           U != E;)  {
         Instruction *User = cast<Instruction>(*U);
-        if (StoreInst *SI = dyn_cast<StoreInst>(User)) {
+        ++U;
+        if (BitCastInst *BC = dyn_cast<BitCastInst>(User)) {
+          // Remove any uses of this alloca in DbgInfoInstrinsics.
+          assert(BC->hasOneUse() && "Unexpected alloca uses!");
+          DbgInfoIntrinsic *DI = cast<DbgInfoIntrinsic>(*BC->use_begin());
+          DI->eraseFromParent();
+          BC->eraseFromParent();
+          continue;
+        } 
+        else if (StoreInst *SI = dyn_cast<StoreInst>(User)) {
           // Remember the basic blocks which define new values for the alloca
           DefiningBlocks.push_back(SI->getParent());
           AllocaPointerVal = SI->getOperand(0);