R600: Move fabs/fneg/sel folding logic into PostProcessIsel

This move makes possible to correctly handle multiples instructions
from a single pattern.

llvm-svn: 190643
This commit is contained in:
Vincent Lejeune 2013-09-12 23:44:44 +00:00
parent f70d60404d
commit ab3baf80a8
4 changed files with 215 additions and 245 deletions

View File

@ -201,92 +201,6 @@ SDNode *AMDGPUDAGToDAGISel::Select(SDNode *N) {
}
switch (Opc) {
default: break;
case AMDGPUISD::CONST_ADDRESS: {
for (SDNode::use_iterator I = N->use_begin(), Next = llvm::next(I);
I != SDNode::use_end(); I = Next) {
Next = llvm::next(I);
if (!I->isMachineOpcode()) {
continue;
}
unsigned Opcode = I->getMachineOpcode();
bool HasDst = TII->getOperandIdx(Opcode, AMDGPU::OpName::dst) > -1;
int SrcIdx = I.getOperandNo();
int SelIdx;
// Unlike MachineInstrs, SDNodes do not have results in their operand
// list, so we need to increment the SrcIdx, since
// R600InstrInfo::getOperandIdx is based on the MachineInstr indices.
if (HasDst) {
SrcIdx++;
}
SelIdx = TII->getSelIdx(I->getMachineOpcode(), SrcIdx);
if (SelIdx < 0) {
continue;
}
SDValue CstOffset;
if (N->getValueType(0).isVector() ||
!SelectGlobalValueConstantOffset(N->getOperand(0), CstOffset))
continue;
// Gather constants values
int SrcIndices[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src2),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_W)
};
std::vector<unsigned> Consts;
for (unsigned i = 0; i < sizeof(SrcIndices) / sizeof(int); i++) {
int OtherSrcIdx = SrcIndices[i];
int OtherSelIdx = TII->getSelIdx(Opcode, OtherSrcIdx);
if (OtherSrcIdx < 0 || OtherSelIdx < 0) {
continue;
}
if (HasDst) {
OtherSrcIdx--;
OtherSelIdx--;
}
if (RegisterSDNode *Reg =
dyn_cast<RegisterSDNode>(I->getOperand(OtherSrcIdx))) {
if (Reg->getReg() == AMDGPU::ALU_CONST) {
ConstantSDNode *Cst = dyn_cast<ConstantSDNode>(I->getOperand(OtherSelIdx));
Consts.push_back(Cst->getZExtValue());
}
}
}
ConstantSDNode *Cst = dyn_cast<ConstantSDNode>(CstOffset);
Consts.push_back(Cst->getZExtValue());
if (!TII->fitsConstReadLimitations(Consts))
continue;
// Convert back to SDNode indices
if (HasDst) {
SrcIdx--;
SelIdx--;
}
std::vector<SDValue> Ops;
for (int i = 0, e = I->getNumOperands(); i != e; ++i) {
if (i == SrcIdx) {
Ops.push_back(CurDAG->getRegister(AMDGPU::ALU_CONST, MVT::f32));
} else if (i == SelIdx) {
Ops.push_back(CstOffset);
} else {
Ops.push_back(I->getOperand(i));
}
}
CurDAG->UpdateNodeOperands(*I, Ops.data(), Ops.size());
}
break;
}
case ISD::BUILD_VECTOR: {
unsigned RegClassID;
const AMDGPUSubtarget &ST = TM.getSubtarget<AMDGPUSubtarget>();
@ -508,38 +422,9 @@ SDNode *AMDGPUDAGToDAGISel::Select(SDNode *N) {
if (ST.getGeneration() <= AMDGPUSubtarget::NORTHERN_ISLANDS) {
const R600InstrInfo *TII =
static_cast<const R600InstrInfo*>(TM.getInstrInfo());
if (Result && Result->isMachineOpcode() && Result->getMachineOpcode() == AMDGPU::DOT_4) {
bool IsModified = false;
do {
std::vector<SDValue> Ops;
for(SDNode::op_iterator I = Result->op_begin(), E = Result->op_end();
I != E; ++I)
Ops.push_back(*I);
IsModified = FoldDotOperands(Result->getMachineOpcode(), TII, Ops);
if (IsModified) {
Result = CurDAG->UpdateNodeOperands(Result, Ops.data(), Ops.size());
}
} while (IsModified);
}
if (Result && Result->isMachineOpcode() &&
!(TII->get(Result->getMachineOpcode()).TSFlags & R600_InstFlag::VECTOR)
&& TII->hasInstrModifiers(Result->getMachineOpcode())) {
// Fold FNEG/FABS
// TODO: Isel can generate multiple MachineInst, we need to recursively
// parse Result
bool IsModified = false;
do {
std::vector<SDValue> Ops;
for(SDNode::op_iterator I = Result->op_begin(), E = Result->op_end();
I != E; ++I)
Ops.push_back(*I);
IsModified = FoldOperands(Result->getMachineOpcode(), TII, Ops);
if (IsModified) {
Result = CurDAG->UpdateNodeOperands(Result, Ops.data(), Ops.size());
}
} while (IsModified);
// If node has a single use which is CLAMP_R600, folds it
if (Result->hasOneUse() && Result->isMachineOpcode()) {
SDNode *PotentialClamp = *Result->use_begin();
@ -564,120 +449,6 @@ SDNode *AMDGPUDAGToDAGISel::Select(SDNode *N) {
return Result;
}
bool AMDGPUDAGToDAGISel::FoldOperand(SDValue &Src, SDValue &Sel, SDValue &Neg,
SDValue &Abs, const R600InstrInfo *TII) {
switch (Src.getOpcode()) {
case ISD::FNEG:
Src = Src.getOperand(0);
Neg = CurDAG->getTargetConstant(1, MVT::i32);
return true;
case ISD::FABS:
if (!Abs.getNode())
return false;
Src = Src.getOperand(0);
Abs = CurDAG->getTargetConstant(1, MVT::i32);
return true;
case ISD::BITCAST:
Src = Src.getOperand(0);
return true;
default:
return false;
}
}
bool AMDGPUDAGToDAGISel::FoldOperands(unsigned Opcode,
const R600InstrInfo *TII, std::vector<SDValue> &Ops) {
int OperandIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src2)
};
int SelIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_sel),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_sel),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src2_sel)
};
int NegIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src2_neg)
};
int AbsIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs),
-1
};
for (unsigned i = 0; i < 3; i++) {
if (OperandIdx[i] < 0)
return false;
SDValue &Src = Ops[OperandIdx[i] - 1];
SDValue &Sel = Ops[SelIdx[i] - 1];
SDValue &Neg = Ops[NegIdx[i] - 1];
SDValue FakeAbs;
SDValue &Abs = (AbsIdx[i] > -1) ? Ops[AbsIdx[i] - 1] : FakeAbs;
if (FoldOperand(Src, Sel, Neg, Abs, TII))
return true;
}
return false;
}
bool AMDGPUDAGToDAGISel::FoldDotOperands(unsigned Opcode,
const R600InstrInfo *TII, std::vector<SDValue> &Ops) {
int OperandIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_W)
};
int SelIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_sel_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_sel_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_sel_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_sel_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_sel_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_sel_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_sel_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_sel_W)
};
int NegIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_W)
};
int AbsIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_W)
};
for (unsigned i = 0; i < 8; i++) {
if (OperandIdx[i] < 0)
return false;
SDValue &Src = Ops[OperandIdx[i] - 1];
SDValue &Sel = Ops[SelIdx[i] - 1];
SDValue &Neg = Ops[NegIdx[i] - 1];
SDValue &Abs = Ops[AbsIdx[i] - 1];
if (FoldOperand(Src, Sel, Neg, Abs, TII))
return true;
}
return false;
}
bool AMDGPUDAGToDAGISel::checkType(const Value *ptr, unsigned int addrspace) {
if (!ptr) {
@ -890,26 +661,27 @@ bool AMDGPUDAGToDAGISel::SelectU24(SDValue Op, SDValue &U24) {
}
void AMDGPUDAGToDAGISel::PostprocessISelDAG() {
if (Subtarget.getGeneration() < AMDGPUSubtarget::SOUTHERN_ISLANDS) {
return;
}
// Go over all selected nodes and try to fold them a bit more
const AMDGPUTargetLowering& Lowering =
(*(const AMDGPUTargetLowering*)getTargetLowering());
for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(),
E = CurDAG->allnodes_end(); I != E; ++I) {
bool IsModified = false;
do {
IsModified = false;
// Go over all selected nodes and try to fold them a bit more
for (SelectionDAG::allnodes_iterator I = CurDAG->allnodes_begin(),
E = CurDAG->allnodes_end(); I != E; ++I) {
SDNode *Node = I;
SDNode *Node = I;
MachineSDNode *MachineNode = dyn_cast<MachineSDNode>(I);
if (!MachineNode)
continue;
MachineSDNode *MachineNode = dyn_cast<MachineSDNode>(I);
if (!MachineNode)
continue;
SDNode *ResNode = Lowering.PostISelFolding(MachineNode, *CurDAG);
if (ResNode != Node) {
ReplaceUses(Node, ResNode);
SDNode *ResNode = Lowering.PostISelFolding(MachineNode, *CurDAG);
if (ResNode != Node) {
ReplaceUses(Node, ResNode);
IsModified = true;
}
}
}
CurDAG->RemoveDeadNodes();
} while (IsModified);
}

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@ -1629,3 +1629,182 @@ SDValue R600TargetLowering::PerformDAGCombine(SDNode *N,
}
return SDValue();
}
static bool
FoldOperand(SDNode *ParentNode, unsigned SrcIdx, SDValue &Src, SDValue &Neg,
SDValue &Abs, SDValue &Sel, SelectionDAG &DAG) {
const R600InstrInfo *TII =
static_cast<const R600InstrInfo *>(DAG.getTarget().getInstrInfo());
if (!Src.isMachineOpcode())
return false;
switch (Src.getMachineOpcode()) {
case AMDGPU::FNEG_R600:
if (!Neg.getNode())
return false;
Src = Src.getOperand(0);
Neg = DAG.getTargetConstant(1, MVT::i32);
return true;
case AMDGPU::FABS_R600:
if (!Abs.getNode())
return false;
Src = Src.getOperand(0);
Abs = DAG.getTargetConstant(1, MVT::i32);
return true;
case AMDGPU::CONST_COPY: {
unsigned Opcode = ParentNode->getMachineOpcode();
bool HasDst = TII->getOperandIdx(Opcode, AMDGPU::OpName::dst) > -1;
if (!Sel.getNode())
return false;
SDValue CstOffset = Src.getOperand(0);
if (ParentNode->getValueType(0).isVector())
return false;
// Gather constants values
int SrcIndices[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src2),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_W)
};
std::vector<unsigned> Consts;
for (unsigned i = 0; i < sizeof(SrcIndices) / sizeof(int); i++) {
int OtherSrcIdx = SrcIndices[i];
int OtherSelIdx = TII->getSelIdx(Opcode, OtherSrcIdx);
if (OtherSrcIdx < 0 || OtherSelIdx < 0)
continue;
if (HasDst) {
OtherSrcIdx--;
OtherSelIdx--;
}
if (RegisterSDNode *Reg =
dyn_cast<RegisterSDNode>(ParentNode->getOperand(OtherSrcIdx))) {
if (Reg->getReg() == AMDGPU::ALU_CONST) {
ConstantSDNode *Cst = dyn_cast<ConstantSDNode>(
ParentNode->getOperand(OtherSelIdx));
Consts.push_back(Cst->getZExtValue());
}
}
}
ConstantSDNode *Cst = dyn_cast<ConstantSDNode>(CstOffset);
Consts.push_back(Cst->getZExtValue());
if (!TII->fitsConstReadLimitations(Consts)) {
return false;
}
Sel = CstOffset;
Src = DAG.getRegister(AMDGPU::ALU_CONST, MVT::f32);
return true;
}
default:
return false;
}
}
/// \brief Fold the instructions after selecting them
SDNode *R600TargetLowering::PostISelFolding(MachineSDNode *Node,
SelectionDAG &DAG) const {
const R600InstrInfo *TII =
static_cast<const R600InstrInfo *>(DAG.getTarget().getInstrInfo());
if (!Node->isMachineOpcode())
return Node;
unsigned Opcode = Node->getMachineOpcode();
SDValue FakeOp;
std::vector<SDValue> Ops;
for(SDNode::op_iterator I = Node->op_begin(), E = Node->op_end();
I != E; ++I)
Ops.push_back(*I);
if (Opcode == AMDGPU::DOT_4) {
int OperandIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_W)
};
int NegIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg_W)
};
int AbsIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs_W),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_X),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_Y),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_Z),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs_W)
};
for (unsigned i = 0; i < 8; i++) {
if (OperandIdx[i] < 0)
return Node;
SDValue &Src = Ops[OperandIdx[i] - 1];
SDValue &Neg = Ops[NegIdx[i] - 1];
SDValue &Abs = Ops[AbsIdx[i] - 1];
bool HasDst = TII->getOperandIdx(Opcode, AMDGPU::OpName::dst) > -1;
int SelIdx = TII->getSelIdx(Opcode, OperandIdx[i]);
if (HasDst)
SelIdx--;
SDValue &Sel = (SelIdx > -1) ? Ops[SelIdx] : FakeOp;
if (FoldOperand(Node, i, Src, Neg, Abs, Sel, DAG))
return DAG.getMachineNode(Opcode, SDLoc(Node), Node->getVTList(), Ops);
}
} else {
if (!TII->hasInstrModifiers(Opcode))
return Node;
int OperandIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src2)
};
int NegIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_neg),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_neg),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src2_neg)
};
int AbsIdx[] = {
TII->getOperandIdx(Opcode, AMDGPU::OpName::src0_abs),
TII->getOperandIdx(Opcode, AMDGPU::OpName::src1_abs),
-1
};
for (unsigned i = 0; i < 3; i++) {
if (OperandIdx[i] < 0)
return Node;
SDValue &Src = Ops[OperandIdx[i] - 1];
SDValue &Neg = Ops[NegIdx[i] - 1];
SDValue FakeAbs;
SDValue &Abs = (AbsIdx[i] > -1) ? Ops[AbsIdx[i] - 1] : FakeAbs;
bool HasDst = TII->getOperandIdx(Opcode, AMDGPU::OpName::dst) > -1;
int SelIdx = TII->getSelIdx(Opcode, OperandIdx[i]);
if (HasDst)
SelIdx--;
SDValue &Sel = (SelIdx > -1) ? Ops[SelIdx] : FakeOp;
if (FoldOperand(Node, i, Src, Neg, Abs, Sel, DAG))
return DAG.getMachineNode(Opcode, SDLoc(Node), Node->getVTList(), Ops);
}
}
return Node;
}

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@ -67,6 +67,7 @@ private:
void getStackAddress(unsigned StackWidth, unsigned ElemIdx,
unsigned &Channel, unsigned &PtrIncr) const;
bool isZero(SDValue Op) const;
virtual SDNode *PostISelFolding(MachineSDNode *N, SelectionDAG &DAG) const;
};
} // End namespace llvm;

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@ -0,0 +1,18 @@
;RUN: llc < %s -march=r600 -mcpu=redwood | FileCheck %s
; CHECK: @main
; CHECK-NOT: MOV
define void @main() {
entry:
%0 = call float @llvm.R600.load.input(i32 0)
%1 = call float @fabs(float %0)
%2 = fptoui float %1 to i32
%3 = bitcast i32 %2 to float
%4 = insertelement <4 x float> undef, float %3, i32 0
call void @llvm.R600.store.swizzle(<4 x float> %4, i32 0, i32 0)
ret void
}
declare float @llvm.R600.load.input(i32) readnone
declare float @fabs(float ) readnone
declare void @llvm.R600.store.swizzle(<4 x float>, i32, i32)