ARM64: initial backend import
This adds a second implementation of the AArch64 architecture to LLVM,
accessible in parallel via the "arm64" triple. The plan over the
coming weeks & months is to merge the two into a single backend,
during which time thorough code review should naturally occur.
Everything will be easier with the target in-tree though, hence this
commit.
llvm-svn: 205090
diff --git a/llvm/lib/Target/ARM64/ARM64SelectionDAGInfo.cpp b/llvm/lib/Target/ARM64/ARM64SelectionDAGInfo.cpp
new file mode 100644
index 0000000..79d507f
--- /dev/null
+++ b/llvm/lib/Target/ARM64/ARM64SelectionDAGInfo.cpp
@@ -0,0 +1,57 @@
+//===-- ARM64SelectionDAGInfo.cpp - ARM64 SelectionDAG Info ---------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file implements the ARM64SelectionDAGInfo class.
+//
+//===----------------------------------------------------------------------===//
+
+#define DEBUG_TYPE "arm64-selectiondag-info"
+#include "ARM64TargetMachine.h"
+using namespace llvm;
+
+ARM64SelectionDAGInfo::ARM64SelectionDAGInfo(const TargetMachine &TM)
+ : TargetSelectionDAGInfo(TM),
+ Subtarget(&TM.getSubtarget<ARM64Subtarget>()) {}
+
+ARM64SelectionDAGInfo::~ARM64SelectionDAGInfo() {}
+
+SDValue ARM64SelectionDAGInfo::EmitTargetCodeForMemset(
+ SelectionDAG &DAG, SDLoc dl, SDValue Chain, SDValue Dst, SDValue Src,
+ SDValue Size, unsigned Align, bool isVolatile,
+ MachinePointerInfo DstPtrInfo) const {
+ // Check to see if there is a specialized entry-point for memory zeroing.
+ ConstantSDNode *V = dyn_cast<ConstantSDNode>(Src);
+ ConstantSDNode *SizeValue = dyn_cast<ConstantSDNode>(Size);
+ const char *bzeroEntry =
+ (V && V->isNullValue()) ? Subtarget->getBZeroEntry() : 0;
+ // For small size (< 256), it is not beneficial to use bzero
+ // instead of memset.
+ if (bzeroEntry && (!SizeValue || SizeValue->getZExtValue() > 256)) {
+ const ARM64TargetLowering &TLI = *static_cast<const ARM64TargetLowering *>(
+ DAG.getTarget().getTargetLowering());
+
+ EVT IntPtr = TLI.getPointerTy();
+ Type *IntPtrTy = getDataLayout()->getIntPtrType(*DAG.getContext());
+ TargetLowering::ArgListTy Args;
+ TargetLowering::ArgListEntry Entry;
+ Entry.Node = Dst;
+ Entry.Ty = IntPtrTy;
+ Args.push_back(Entry);
+ Entry.Node = Size;
+ Args.push_back(Entry);
+ TargetLowering::CallLoweringInfo CLI(
+ Chain, Type::getVoidTy(*DAG.getContext()), false, false, false, false,
+ 0, CallingConv::C, /*isTailCall=*/false,
+ /*doesNotRet=*/false, /*isReturnValueUsed=*/false,
+ DAG.getExternalSymbol(bzeroEntry, IntPtr), Args, DAG, dl);
+ std::pair<SDValue, SDValue> CallResult = TLI.LowerCallTo(CLI);
+ return CallResult.second;
+ }
+ return SDValue();
+}