[Memcpy Loop Lowering] Remove the fixed int8 lowering.

Switch over to the lowering that uses target supplied operand types.

Differential Revision: https://reviews.llvm.org/D41201

llvm-svn: 320989

1 files changed, 13 insertions, 80 deletions

diff --git a/llvm/lib/Transforms/Utils/LowerMemIntrinsics.cpp b/llvm/lib/Transforms/Utils/LowerMemIntrinsics.cpp
index 6641e8ba496..57dc225e9da 100644
--- a/llvm/lib/Transforms/Utils/LowerMemIntrinsics.cpp
+++ b/llvm/lib/Transforms/Utils/LowerMemIntrinsics.cpp
@@ -263,61 +263,6 @@ void llvm::createMemCpyLoopUnknownSize(Instruction *InsertBefore,
   }
 }
 
-void llvm::createMemCpyLoop(Instruction *InsertBefore,
-                            Value *SrcAddr, Value *DstAddr, Value *CopyLen,
-                            unsigned SrcAlign, unsigned DestAlign,
-                            bool SrcIsVolatile, bool DstIsVolatile) {
-  Type *TypeOfCopyLen = CopyLen->getType();
-
-  BasicBlock *OrigBB = InsertBefore->getParent();
-  Function *F = OrigBB->getParent();
-  BasicBlock *NewBB =
-    InsertBefore->getParent()->splitBasicBlock(InsertBefore, "split");
-  BasicBlock *LoopBB = BasicBlock::Create(F->getContext(), "loadstoreloop",
-                                          F, NewBB);
-
-  IRBuilder<> Builder(OrigBB->getTerminator());
-
-  // SrcAddr and DstAddr are expected to be pointer types,
-  // so no check is made here.
-  unsigned SrcAS = cast<PointerType>(SrcAddr->getType())->getAddressSpace();
-  unsigned DstAS = cast<PointerType>(DstAddr->getType())->getAddressSpace();
-
-  // Cast pointers to (char *)
-  SrcAddr = Builder.CreateBitCast(SrcAddr, Builder.getInt8PtrTy(SrcAS));
-  DstAddr = Builder.CreateBitCast(DstAddr, Builder.getInt8PtrTy(DstAS));
-
-  Builder.CreateCondBr(
-      Builder.CreateICmpEQ(ConstantInt::get(TypeOfCopyLen, 0), CopyLen), NewBB,
-      LoopBB);
-  OrigBB->getTerminator()->eraseFromParent();
-
-  IRBuilder<> LoopBuilder(LoopBB);
-  PHINode *LoopIndex = LoopBuilder.CreatePHI(TypeOfCopyLen, 0);
-  LoopIndex->addIncoming(ConstantInt::get(TypeOfCopyLen, 0), OrigBB);
-
-  // load from SrcAddr+LoopIndex
-  // TODO: we can leverage the align parameter of llvm.memcpy for more efficient
-  // word-sized loads and stores.
-  Value *Element =
-    LoopBuilder.CreateLoad(LoopBuilder.CreateInBoundsGEP(
-                             LoopBuilder.getInt8Ty(), SrcAddr, LoopIndex),
-                           SrcIsVolatile);
-  // store at DstAddr+LoopIndex
-  LoopBuilder.CreateStore(Element,
-                          LoopBuilder.CreateInBoundsGEP(LoopBuilder.getInt8Ty(),
-                                                        DstAddr, LoopIndex),
-                          DstIsVolatile);
-
-  // The value for LoopIndex coming from backedge is (LoopIndex + 1)
-  Value *NewIndex =
-    LoopBuilder.CreateAdd(LoopIndex, ConstantInt::get(TypeOfCopyLen, 1));
-  LoopIndex->addIncoming(NewIndex, LoopBB);
-
-  LoopBuilder.CreateCondBr(LoopBuilder.CreateICmpULT(NewIndex, CopyLen), LoopBB,
-                           NewBB);
-}
-
 // Lower memmove to IR. memmove is required to correctly copy overlapping memory
 // regions; therefore, it has to check the relative positions of the source and
 // destination pointers and choose the copy direction accordingly.
@@ -459,38 +404,26 @@ static void createMemSetLoop(Instruction *InsertBefore,
 
 void llvm::expandMemCpyAsLoop(MemCpyInst *Memcpy,
                               const TargetTransformInfo &TTI) {
-  // Original implementation
-  if (!TTI.useWideIRMemcpyLoopLowering()) {
-    createMemCpyLoop(/* InsertBefore */ Memcpy,
-                     /* SrcAddr */ Memcpy->getRawSource(),
-                     /* DstAddr */ Memcpy->getRawDest(),
-                     /* CopyLen */ Memcpy->getLength(),
-                     /* SrcAlign */ Memcpy->getAlignment(),
-                     /* DestAlign */ Memcpy->getAlignment(),
-                     /* SrcIsVolatile */ Memcpy->isVolatile(),
-                     /* DstIsVolatile */ Memcpy->isVolatile());
+  if (ConstantInt *CI = dyn_cast<ConstantInt>(Memcpy->getLength())) {
+    createMemCpyLoopKnownSize(/* InsertBefore */ Memcpy,
+                              /* SrcAddr */ Memcpy->getRawSource(),
+                              /* DstAddr */ Memcpy->getRawDest(),
+                              /* CopyLen */ CI,
+                              /* SrcAlign */ Memcpy->getAlignment(),
+                              /* DestAlign */ Memcpy->getAlignment(),
+                              /* SrcIsVolatile */ Memcpy->isVolatile(),
+                              /* DstIsVolatile */ Memcpy->isVolatile(),
+                              /* TargetTransformInfo */ TTI);
   } else {
-    if (ConstantInt *CI = dyn_cast<ConstantInt>(Memcpy->getLength())) {
-      createMemCpyLoopKnownSize(/* InsertBefore */ Memcpy,
+    createMemCpyLoopUnknownSize(/* InsertBefore */ Memcpy,
                                 /* SrcAddr */ Memcpy->getRawSource(),
                                 /* DstAddr */ Memcpy->getRawDest(),
-                                /* CopyLen */ CI,
+                                /* CopyLen */ Memcpy->getLength(),
                                 /* SrcAlign */ Memcpy->getAlignment(),
                                 /* DestAlign */ Memcpy->getAlignment(),
                                 /* SrcIsVolatile */ Memcpy->isVolatile(),
                                 /* DstIsVolatile */ Memcpy->isVolatile(),
-                                /* TargetTransformInfo */ TTI);
-    } else {
-      createMemCpyLoopUnknownSize(/* InsertBefore */ Memcpy,
-                                  /* SrcAddr */ Memcpy->getRawSource(),
-                                  /* DstAddr */ Memcpy->getRawDest(),
-                                  /* CopyLen */ Memcpy->getLength(),
-                                  /* SrcAlign */ Memcpy->getAlignment(),
-                                  /* DestAlign */ Memcpy->getAlignment(),
-                                  /* SrcIsVolatile */ Memcpy->isVolatile(),
-                                  /* DstIsVolatile */ Memcpy->isVolatile(),
-                                  /* TargetTransfomrInfo */ TTI);
-    }
+                                /* TargetTransfomrInfo */ TTI);
   }
 }