Refactor isConsecutiveLoad from X86 to TargetLowering so DAG combiner can make use of it.

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@50991 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
Evan Cheng 2008-05-12 19:56:52 +00:00
parent c1b7f52fbe
commit ad4196b44a
3 changed files with 95 additions and 67 deletions

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@ -19,6 +19,7 @@
#include "llvm/Target/TargetRegisterInfo.h"
#include "llvm/GlobalVariable.h"
#include "llvm/DerivedTypes.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/ADT/StringExtras.h"
#include "llvm/ADT/STLExtras.h"
@ -1478,6 +1479,73 @@ TargetLowering::SimplifySetCC(MVT::ValueType VT, SDOperand N0, SDOperand N1,
return SDOperand();
}
/// isGAPlusOffset - Returns true (and the GlobalValue and the offset) if the
/// node is a GlobalAddress + offset.
bool TargetLowering::isGAPlusOffset(SDNode *N, GlobalValue* &GA,
int64_t &Offset) const {
if (isa<GlobalAddressSDNode>(N)) {
GA = cast<GlobalAddressSDNode>(N)->getGlobal();
return true;
}
if (N->getOpcode() == ISD::ADD) {
SDOperand N1 = N->getOperand(0);
SDOperand N2 = N->getOperand(1);
if (isGAPlusOffset(N1.Val, GA, Offset)) {
ConstantSDNode *V = dyn_cast<ConstantSDNode>(N2);
if (V) {
Offset += V->getSignExtended();
return true;
}
} else if (isGAPlusOffset(N2.Val, GA, Offset)) {
ConstantSDNode *V = dyn_cast<ConstantSDNode>(N1);
if (V) {
Offset += V->getSignExtended();
return true;
}
}
}
return false;
}
/// isConsecutiveLoad - Return true if LD (which must be a LoadSDNode) is
/// loading 'Bytes' bytes from a location that is 'Dist' units away from the
/// location that the 'Base' load is loading from.
bool TargetLowering::isConsecutiveLoad(SDNode *LD, SDNode *Base,
unsigned Bytes, int Dist,
MachineFrameInfo *MFI) const {
if (LD->getOperand(0).Val != Base->getOperand(0).Val)
return false;
MVT::ValueType VT = LD->getValueType(0);
if (MVT::getSizeInBits(VT) / 8 != Bytes)
return false;
SDOperand Loc = LD->getOperand(1);
SDOperand BaseLoc = Base->getOperand(1);
if (Loc.getOpcode() == ISD::FrameIndex) {
if (BaseLoc.getOpcode() != ISD::FrameIndex)
return false;
int FI = cast<FrameIndexSDNode>(Loc)->getIndex();
int BFI = cast<FrameIndexSDNode>(BaseLoc)->getIndex();
int FS = MFI->getObjectSize(FI);
int BFS = MFI->getObjectSize(BFI);
if (FS != BFS || FS != (int)Bytes) return false;
return MFI->getObjectOffset(FI) == (MFI->getObjectOffset(BFI) + Dist*Bytes);
}
GlobalValue *GV1 = NULL;
GlobalValue *GV2 = NULL;
int64_t Offset1 = 0;
int64_t Offset2 = 0;
bool isGA1 = isGAPlusOffset(Loc.Val, GV1, Offset1);
bool isGA2 = isGAPlusOffset(BaseLoc.Val, GV2, Offset2);
if (isGA1 && isGA2 && GV1 == GV2)
return Offset1 == (Offset2 + Dist*Bytes);
return false;
}
SDOperand TargetLowering::
PerformDAGCombine(SDNode *N, DAGCombinerInfo &DCI) const {
// Default implementation: no optimization.

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@ -6194,71 +6194,23 @@ static SDOperand getShuffleScalarElt(SDNode *N, unsigned i, SelectionDAG &DAG) {
}
/// isGAPlusOffset - Returns true (and the GlobalValue and the offset) if the
/// node is a GlobalAddress + an offset.
static bool isGAPlusOffset(SDNode *N, GlobalValue* &GA, int64_t &Offset) {
unsigned Opc = N->getOpcode();
if (Opc == X86ISD::Wrapper) {
if (dyn_cast<GlobalAddressSDNode>(N->getOperand(0))) {
/// node is a GlobalAddress + offset.
bool X86TargetLowering::isGAPlusOffset(SDNode *N,
GlobalValue* &GA, int64_t &Offset) const{
if (N->getOpcode() == X86ISD::Wrapper) {
if (isa<GlobalAddressSDNode>(N->getOperand(0))) {
GA = cast<GlobalAddressSDNode>(N->getOperand(0))->getGlobal();
return true;
}
} else if (Opc == ISD::ADD) {
SDOperand N1 = N->getOperand(0);
SDOperand N2 = N->getOperand(1);
if (isGAPlusOffset(N1.Val, GA, Offset)) {
ConstantSDNode *V = dyn_cast<ConstantSDNode>(N2);
if (V) {
Offset += V->getSignExtended();
return true;
}
} else if (isGAPlusOffset(N2.Val, GA, Offset)) {
ConstantSDNode *V = dyn_cast<ConstantSDNode>(N1);
if (V) {
Offset += V->getSignExtended();
return true;
}
}
}
return false;
return TargetLowering::isGAPlusOffset(N, GA, Offset);
}
/// isConsecutiveLoad - Returns true if N is loading from an address of Base
/// + Dist * Size.
static bool isConsecutiveLoad(SDNode *N, SDNode *Base, int Dist, int Size,
MachineFrameInfo *MFI) {
if (N->getOperand(0).Val != Base->getOperand(0).Val)
return false;
SDOperand Loc = N->getOperand(1);
SDOperand BaseLoc = Base->getOperand(1);
if (Loc.getOpcode() == ISD::FrameIndex) {
if (BaseLoc.getOpcode() != ISD::FrameIndex)
return false;
int FI = cast<FrameIndexSDNode>(Loc)->getIndex();
int BFI = cast<FrameIndexSDNode>(BaseLoc)->getIndex();
int FS = MFI->getObjectSize(FI);
int BFS = MFI->getObjectSize(BFI);
if (FS != BFS || FS != Size) return false;
return MFI->getObjectOffset(FI) == (MFI->getObjectOffset(BFI) + Dist*Size);
} else {
GlobalValue *GV1 = NULL;
GlobalValue *GV2 = NULL;
int64_t Offset1 = 0;
int64_t Offset2 = 0;
bool isGA1 = isGAPlusOffset(Loc.Val, GV1, Offset1);
bool isGA2 = isGAPlusOffset(BaseLoc.Val, GV2, Offset2);
if (isGA1 && isGA2 && GV1 == GV2)
return Offset1 == (Offset2 + Dist*Size);
}
return false;
}
static bool isBaseAlignmentOfN(unsigned N, SDNode *Base, MachineFrameInfo *MFI,
const X86Subtarget *Subtarget) {
static bool isBaseAlignmentOfN(unsigned N, SDNode *Base,
const TargetLowering &TLI) {
GlobalValue *GV;
int64_t Offset = 0;
if (isGAPlusOffset(Base, GV, Offset))
if (TLI.isGAPlusOffset(Base, GV, Offset))
return (GV->getAlignment() >= N && (Offset % N) == 0);
// DAG combine handles the stack object case.
return false;
@ -6266,8 +6218,9 @@ static bool isBaseAlignmentOfN(unsigned N, SDNode *Base, MachineFrameInfo *MFI,
static bool EltsFromConsecutiveLoads(SDNode *N, SDOperand PermMask,
unsigned NumElems, MVT::ValueType EVT,
MachineFrameInfo *MFI,
SelectionDAG &DAG, SDNode *&Base) {
SDNode *&Base,
SelectionDAG &DAG, MachineFrameInfo *MFI,
const TargetLowering &TLI) {
Base = NULL;
for (unsigned i = 0; i < NumElems; ++i) {
SDOperand Idx = PermMask.getOperand(i);
@ -6291,7 +6244,8 @@ static bool EltsFromConsecutiveLoads(SDNode *N, SDOperand PermMask,
if (Elt.getOpcode() == ISD::UNDEF)
continue;
if (!isConsecutiveLoad(Elt.Val, Base, i, MVT::getSizeInBits(EVT)/8,MFI))
if (!TLI.isConsecutiveLoad(Elt.Val, Base,
MVT::getSizeInBits(EVT)/8, i, MFI))
return false;
}
return true;
@ -6302,18 +6256,19 @@ static bool EltsFromConsecutiveLoads(SDNode *N, SDOperand PermMask,
/// if the load addresses are consecutive, non-overlapping, and in the right
/// order.
static SDOperand PerformShuffleCombine(SDNode *N, SelectionDAG &DAG,
const X86Subtarget *Subtarget) {
const TargetLowering &TLI) {
MachineFrameInfo *MFI = DAG.getMachineFunction().getFrameInfo();
MVT::ValueType VT = N->getValueType(0);
MVT::ValueType EVT = MVT::getVectorElementType(VT);
SDOperand PermMask = N->getOperand(2);
unsigned NumElems = PermMask.getNumOperands();
SDNode *Base = NULL;
if (!EltsFromConsecutiveLoads(N, PermMask, NumElems, EVT, MFI, DAG, Base))
if (!EltsFromConsecutiveLoads(N, PermMask, NumElems, EVT, Base,
DAG, MFI, TLI))
return SDOperand();
LoadSDNode *LD = cast<LoadSDNode>(Base);
if (isBaseAlignmentOfN(16, Base->getOperand(1).Val, MFI, Subtarget))
if (isBaseAlignmentOfN(16, Base->getOperand(1).Val, TLI))
return DAG.getLoad(VT, LD->getChain(), LD->getBasePtr(), LD->getSrcValue(),
LD->getSrcValueOffset(), LD->isVolatile());
return DAG.getLoad(VT, LD->getChain(), LD->getBasePtr(), LD->getSrcValue(),
@ -6329,7 +6284,8 @@ static SDNode *getBuildPairElt(SDNode *N, unsigned i) {
}
static SDOperand PerformBuildVectorCombine(SDNode *N, SelectionDAG &DAG,
const X86Subtarget *Subtarget) {
const X86Subtarget *Subtarget,
const TargetLowering &TLI) {
// Ignore single operand BUILD_VECTOR.
if (N->getNumOperands() == 1)
return SDOperand();
@ -6360,7 +6316,7 @@ static SDOperand PerformBuildVectorCombine(SDNode *N, SelectionDAG &DAG,
return SDOperand();
SDNode *NextLD = getBuildPairElt(Pair, 1);
if (!ISD::isNON_EXTLoad(NextLD) ||
!isConsecutiveLoad(NextLD, Base, 1, 4/*32 bits*/, MFI))
!TLI.isConsecutiveLoad(NextLD, Base, 4/*32 bits*/, 1, MFI))
return SDOperand();
}
LoadSDNode *LD = cast<LoadSDNode>(Base);
@ -6564,8 +6520,9 @@ SDOperand X86TargetLowering::PerformDAGCombine(SDNode *N,
SelectionDAG &DAG = DCI.DAG;
switch (N->getOpcode()) {
default: break;
case ISD::VECTOR_SHUFFLE: return PerformShuffleCombine(N, DAG, Subtarget);
case ISD::BUILD_VECTOR: return PerformBuildVectorCombine(N, DAG, Subtarget);
case ISD::VECTOR_SHUFFLE: return PerformShuffleCombine(N, DAG, *this);
case ISD::BUILD_VECTOR:
return PerformBuildVectorCombine(N, DAG, Subtarget, *this);
case ISD::SELECT: return PerformSELECTCombine(N, DAG, Subtarget);
case ISD::STORE: return PerformSTORECombine(N, DAG, Subtarget);
case X86ISD::FXOR:

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@ -369,6 +369,9 @@ namespace llvm {
APInt &KnownOne,
const SelectionDAG &DAG,
unsigned Depth = 0) const;
virtual bool
isGAPlusOffset(SDNode *N, GlobalValue* &GA, int64_t &Offset) const;
SDOperand getReturnAddressFrameIndex(SelectionDAG &DAG);