llvm-6502/include/llvm/Target/TargetSelectionDAGInfo.h
Dan Gohman 17c4a621fe Fix a comment.
git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@103483 91177308-0d34-0410-b5e6-96231b3b80d8
2010-05-11 18:03:41 +00:00

102 lines
4.3 KiB
C++

//==-- llvm/Target/TargetSelectionDAGInfo.h - SelectionDAG Info --*- C++ -*-==//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file declares the TargetSelectionDAGInfo class, which targets can
// subclass to parameterize the SelectionDAG lowering and instruction
// selection process.
//
//===----------------------------------------------------------------------===//
#ifndef LLVM_TARGET_TARGETSELECTIONDAGINFO_H
#define LLVM_TARGET_TARGETSELECTIONDAGINFO_H
#include "llvm/CodeGen/SelectionDAGNodes.h"
namespace llvm {
class TargetData;
class TargetMachine;
//===----------------------------------------------------------------------===//
/// TargetSelectionDAGInfo - Targets can subclass this to parameterize the
/// SelectionDAG lowering and instruction selection process.
///
class TargetSelectionDAGInfo {
TargetSelectionDAGInfo(const TargetSelectionDAGInfo &); // DO NOT IMPLEMENT
void operator=(const TargetSelectionDAGInfo &); // DO NOT IMPLEMENT
const TargetData *TD;
protected:
const TargetData *getTargetData() const { return TD; }
public:
explicit TargetSelectionDAGInfo(const TargetMachine &TM);
virtual ~TargetSelectionDAGInfo();
/// EmitTargetCodeForMemcpy - Emit target-specific code that performs a
/// memcpy. This can be used by targets to provide code sequences for cases
/// that don't fit the target's parameters for simple loads/stores and can be
/// more efficient than using a library call. This function can return a null
/// SDValue if the target declines to use custom code and a different
/// lowering strategy should be used.
///
/// If AlwaysInline is true, the size is constant and the target should not
/// emit any calls and is strongly encouraged to attempt to emit inline code
/// even if it is beyond the usual threshold because this intrinsic is being
/// expanded in a place where calls are not feasible (e.g. within the prologue
/// for another call). If the target chooses to decline an AlwaysInline
/// request here, legalize will resort to using simple loads and stores.
virtual SDValue
EmitTargetCodeForMemcpy(SelectionDAG &DAG, DebugLoc dl,
SDValue Chain,
SDValue Op1, SDValue Op2,
SDValue Op3, unsigned Align, bool isVolatile,
bool AlwaysInline,
const Value *DstSV, uint64_t DstOff,
const Value *SrcSV, uint64_t SrcOff) const {
return SDValue();
}
/// EmitTargetCodeForMemmove - Emit target-specific code that performs a
/// memmove. This can be used by targets to provide code sequences for cases
/// that don't fit the target's parameters for simple loads/stores and can be
/// more efficient than using a library call. This function can return a null
/// SDValue if the target declines to use custom code and a different
/// lowering strategy should be used.
virtual SDValue
EmitTargetCodeForMemmove(SelectionDAG &DAG, DebugLoc dl,
SDValue Chain,
SDValue Op1, SDValue Op2,
SDValue Op3, unsigned Align, bool isVolatile,
const Value *DstSV, uint64_t DstOff,
const Value *SrcSV, uint64_t SrcOff) const {
return SDValue();
}
/// EmitTargetCodeForMemset - Emit target-specific code that performs a
/// memset. This can be used by targets to provide code sequences for cases
/// that don't fit the target's parameters for simple stores and can be more
/// efficient than using a library call. This function can return a null
/// SDValue if the target declines to use custom code and a different
/// lowering strategy should be used.
virtual SDValue
EmitTargetCodeForMemset(SelectionDAG &DAG, DebugLoc dl,
SDValue Chain,
SDValue Op1, SDValue Op2,
SDValue Op3, unsigned Align, bool isVolatile,
const Value *DstSV, uint64_t DstOff) const {
return SDValue();
}
};
} // end llvm namespace
#endif