Revert "r306541 - Add zero-length check to memcpy/memset load store loop expansion"

Segfaults in non-optimized builds. I'll get a stack trace and a
reproducer to Teresa.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306793 91177308-0d34-0410-b5e6-96231b3b80d8

diff --git a/lib/Transforms/Utils/LowerMemIntrinsics.cpp b/lib/Transforms/Utils/LowerMemIntrinsics.cpp
index ef829d43b7daa11ce529a4932e4892c8577a1f75..0a51f9a0e4a26eee228a3595d70c5b371a3b0a3a 100644 (file)
--- a/lib/Transforms/Utils/LowerMemIntrinsics.cpp
+++ b/lib/Transforms/Utils/LowerMemIntrinsics.cpp
@@ -27,11 +27,8 @@ void llvm::createMemCpyLoop(Instruction *InsertBefore,
   BasicBlock *LoopBB = BasicBlock::Create(F->getContext(), "loadstoreloop",
                                           F, NewBB);
 
+  OrigBB->getTerminator()->setSuccessor(0, LoopBB);
   IRBuilder<> Builder(OrigBB->getTerminator());
-  Builder.CreateCondBr(
-      Builder.CreateICmpEQ(ConstantInt::get(TypeOfCopyLen, 0), CopyLen), NewBB,
-      LoopBB);
-  OrigBB->getTerminator()->eraseFromParent();
 
   // SrcAddr and DstAddr are expected to be pointer types,
   // so no check is made here.
@@ -170,7 +167,6 @@ static void createMemMoveLoop(Instruction *InsertBefore,
 static void createMemSetLoop(Instruction *InsertBefore,
                              Value *DstAddr, Value *CopyLen, Value *SetValue,
                              unsigned Align, bool IsVolatile) {
-  Type *TypeOfCopyLen = CopyLen->getType();
   BasicBlock *OrigBB = InsertBefore->getParent();
   Function *F = OrigBB->getParent();
   BasicBlock *NewBB =
@@ -178,11 +174,8 @@ static void createMemSetLoop(Instruction *InsertBefore,
   BasicBlock *LoopBB
     = BasicBlock::Create(F->getContext(), "loadstoreloop", F, NewBB);
 
+  OrigBB->getTerminator()->setSuccessor(0, LoopBB);
   IRBuilder<> Builder(OrigBB->getTerminator());
-  Builder.CreateCondBr(
-      Builder.CreateICmpEQ(ConstantInt::get(TypeOfCopyLen, 0), CopyLen), NewBB,
-      LoopBB);
-  OrigBB->getTerminator()->eraseFromParent();
 
   // Cast pointer to the type of value getting stored
   unsigned dstAS = cast<PointerType>(DstAddr->getType())->getAddressSpace();
@@ -190,8 +183,8 @@ static void createMemSetLoop(Instruction *InsertBefore,
                                   PointerType::get(SetValue->getType(), dstAS));
 
   IRBuilder<> LoopBuilder(LoopBB);
-  PHINode *LoopIndex = LoopBuilder.CreatePHI(TypeOfCopyLen, 0);
-  LoopIndex->addIncoming(ConstantInt::get(TypeOfCopyLen, 0), OrigBB);
+  PHINode *LoopIndex = LoopBuilder.CreatePHI(CopyLen->getType(), 0);
+  LoopIndex->addIncoming(ConstantInt::get(CopyLen->getType(), 0), OrigBB);
 
   LoopBuilder.CreateStore(
       SetValue,
@@ -199,7 +192,7 @@ static void createMemSetLoop(Instruction *InsertBefore,
       IsVolatile);
 
   Value *NewIndex =
-      LoopBuilder.CreateAdd(LoopIndex, ConstantInt::get(TypeOfCopyLen, 1));
+      LoopBuilder.CreateAdd(LoopIndex, ConstantInt::get(CopyLen->getType(), 1));
   LoopIndex->addIncoming(NewIndex, LoopBB);
 
   LoopBuilder.CreateCondBr(LoopBuilder.CreateICmpULT(NewIndex, CopyLen), LoopBB,

diff --git a/test/CodeGen/NVPTX/lower-aggr-copies.ll b/test/CodeGen/NVPTX/lower-aggr-copies.ll
index f522c6722ee6f9ec4ab9313a99f83c425b6470d8..192d4becb05963fdb8fe36e1d30bcdbc15e23e77 100644 (file)
--- a/test/CodeGen/NVPTX/lower-aggr-copies.ll
+++ b/test/CodeGen/NVPTX/lower-aggr-copies.ll
@@ -17,8 +17,6 @@ entry:
   ret i8* %dst
 
 ; IR-LABEL:   @memcpy_caller
-; IR:         [[CMPREG:%[0-9]+]] = icmp eq i64 0, %n
-; IR:         br i1 [[CMPREG]], label %split, label %loadstoreloop
 ; IR:         loadstoreloop:
 ; IR:         [[LOADPTR:%[0-9]+]] = getelementptr inbounds i8, i8* %src, i64
 ; IR-NEXT:    [[VAL:%[0-9]+]] = load i8, i8* [[LOADPTR]]
@@ -75,8 +73,6 @@ entry:
 
 ; IR-LABEL:   @memset_caller
 ; IR:         [[VAL:%[0-9]+]] = trunc i32 %c to i8
-; IR:         [[CMPREG:%[0-9]+]] = icmp eq i64 0, %n
-; IR:         br i1 [[CMPREG]], label %split, label %loadstoreloop
 ; IR:         loadstoreloop:
 ; IR:         [[STOREPTR:%[0-9]+]] = getelementptr inbounds i8, i8* %dst, i64
 ; IR-NEXT:    store i8 [[VAL]], i8* [[STOREPTR]]