R600: Don't promote allocas when one of the users is a ptrtoint instruction

We need to figure out how to track ptrtoint values all the
way until result is converted back to a pointer in order
to correctly rewrite the pointer type.

llvm-svn: 220997

1 files changed, 19 insertions, 6 deletions

diff --git a/llvm/lib/Target/R600/AMDGPUPromoteAlloca.cpp b/llvm/lib/Target/R600/AMDGPUPromoteAlloca.cpp
index 8e85b03d4eb..b81fef47d55 100644
--- a/llvm/lib/Target/R600/AMDGPUPromoteAlloca.cpp
+++ b/llvm/lib/Target/R600/AMDGPUPromoteAlloca.cpp
@@ -234,7 +234,8 @@ static bool tryPromoteAllocaToVector(AllocaInst *Alloca) {
   return true;
 }
 
-static void collectUsesWithPtrTypes(Value *Val, std::vector<Value*> &WorkList) {
+static bool collectUsesWithPtrTypes(Value *Val, std::vector<Value*> &WorkList) {
+  bool Success = true;
   for (User *User : Val->users()) {
     if(std::find(WorkList.begin(), WorkList.end(), User) != WorkList.end())
       continue;
@@ -242,11 +243,20 @@ static void collectUsesWithPtrTypes(Value *Val, std::vector<Value*> &WorkList) {
       WorkList.push_back(User);
       continue;
     }
+
+    // FIXME: Correctly handle ptrtoint instructions.
+    Instruction *UseInst = dyn_cast<Instruction>(User);
+    if (UseInst && UseInst->getOpcode() == Instruction::PtrToInt)
+      return false;
+
     if (!User->getType()->isPointerTy())
       continue;
+
     WorkList.push_back(User);
-    collectUsesWithPtrTypes(User, WorkList);
+
+    Success &= collectUsesWithPtrTypes(User, WorkList);
   }
+  return Success;
 }
 
 void AMDGPUPromoteAlloca::visitAlloca(AllocaInst &I) {
@@ -274,6 +284,13 @@ void AMDGPUPromoteAlloca::visitAlloca(AllocaInst &I) {
     return;
   }
 
+  std::vector<Value*> WorkList;
+
+  if (!collectUsesWithPtrTypes(&I, WorkList)) {
+    DEBUG(dbgs() << " Do not know how to convert all uses\n");
+    return;
+  }
+
   DEBUG(dbgs() << "Promoting alloca to local memory\n");
   LocalMemAvailable -= AllocaSize;
 
@@ -320,10 +337,6 @@ void AMDGPUPromoteAlloca::visitAlloca(AllocaInst &I) {
   I.replaceAllUsesWith(Offset);
   I.eraseFromParent();
 
-  std::vector<Value*> WorkList;
-
-  collectUsesWithPtrTypes(Offset, WorkList);
-
   for (std::vector<Value*>::iterator i = WorkList.begin(),
                                      e = WorkList.end(); i != e; ++i) {
     Value *V = *i;