llvm-6502/lib/Target/PTX/PTXInstrInfo.cpp
Dan Bailey b05a8a8f02 PTX: Add support for i8 type and introduce associated .b8 registers
The i8 type is required for boolean values, but can only use ld, st and mov instructions. The i1 type continues to be used for predicates.



git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@133814 91177308-0d34-0410-b5e6-96231b3b80d8
2011-06-24 19:27:10 +00:00

414 lines
14 KiB
C++

//===- PTXInstrInfo.cpp - PTX Instruction Information ---------------------===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
//
// This file contains the PTX implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#define DEBUG_TYPE "ptx-instrinfo"
#include "PTX.h"
#include "PTXInstrInfo.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/SelectionDAG.h"
#include "llvm/CodeGen/SelectionDAGNodes.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
using namespace llvm;
#include "PTXGenInstrInfo.inc"
PTXInstrInfo::PTXInstrInfo(PTXTargetMachine &_TM)
: TargetInstrInfoImpl(PTXInsts, array_lengthof(PTXInsts)),
RI(_TM, *this), TM(_TM) {}
static const struct map_entry {
const TargetRegisterClass *cls;
const int opcode;
} map[] = {
{ &PTX::RegI8RegClass, PTX::MOVU8rr },
{ &PTX::RegI16RegClass, PTX::MOVU16rr },
{ &PTX::RegI32RegClass, PTX::MOVU32rr },
{ &PTX::RegI64RegClass, PTX::MOVU64rr },
{ &PTX::RegF32RegClass, PTX::MOVF32rr },
{ &PTX::RegF64RegClass, PTX::MOVF64rr },
{ &PTX::RegPredRegClass, PTX::MOVPREDrr }
};
void PTXInstrInfo::copyPhysReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I, DebugLoc DL,
unsigned DstReg, unsigned SrcReg,
bool KillSrc) const {
for (int i = 0, e = sizeof(map)/sizeof(map[0]); i != e; ++ i) {
if (map[i].cls->contains(DstReg, SrcReg)) {
const TargetInstrDesc &TID = get(map[i].opcode);
MachineInstr *MI = BuildMI(MBB, I, DL, TID, DstReg).
addReg(SrcReg, getKillRegState(KillSrc));
AddDefaultPredicate(MI);
return;
}
}
llvm_unreachable("Impossible reg-to-reg copy");
}
bool PTXInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator I,
unsigned DstReg, unsigned SrcReg,
const TargetRegisterClass *DstRC,
const TargetRegisterClass *SrcRC,
DebugLoc DL) const {
if (DstRC != SrcRC)
return false;
for (int i = 0, e = sizeof(map)/sizeof(map[0]); i != e; ++ i)
if (DstRC == map[i].cls) {
const TargetInstrDesc &TID = get(map[i].opcode);
MachineInstr *MI = BuildMI(MBB, I, DL, TID, DstReg).addReg(SrcReg);
AddDefaultPredicate(MI);
return true;
}
return false;
}
bool PTXInstrInfo::isMoveInstr(const MachineInstr& MI,
unsigned &SrcReg, unsigned &DstReg,
unsigned &SrcSubIdx, unsigned &DstSubIdx) const {
switch (MI.getOpcode()) {
default:
return false;
case PTX::MOVU16rr:
case PTX::MOVU32rr:
case PTX::MOVU64rr:
case PTX::MOVF32rr:
case PTX::MOVF64rr:
case PTX::MOVPREDrr:
assert(MI.getNumOperands() >= 2 &&
MI.getOperand(0).isReg() && MI.getOperand(1).isReg() &&
"Invalid register-register move instruction");
SrcSubIdx = DstSubIdx = 0; // No sub-registers
DstReg = MI.getOperand(0).getReg();
SrcReg = MI.getOperand(1).getReg();
return true;
}
}
// predicate support
bool PTXInstrInfo::isPredicated(const MachineInstr *MI) const {
int i = MI->findFirstPredOperandIdx();
return i != -1 && MI->getOperand(i).getReg() != PTX::NoRegister;
}
bool PTXInstrInfo::isUnpredicatedTerminator(const MachineInstr *MI) const {
return !isPredicated(MI) && get(MI->getOpcode()).isTerminator();
}
bool PTXInstrInfo::
PredicateInstruction(MachineInstr *MI,
const SmallVectorImpl<MachineOperand> &Pred) const {
if (Pred.size() < 2)
llvm_unreachable("lesser than 2 predicate operands are provided");
int i = MI->findFirstPredOperandIdx();
if (i == -1)
llvm_unreachable("missing predicate operand");
MI->getOperand(i).setReg(Pred[0].getReg());
MI->getOperand(i+1).setImm(Pred[1].getImm());
return true;
}
bool PTXInstrInfo::
SubsumesPredicate(const SmallVectorImpl<MachineOperand> &Pred1,
const SmallVectorImpl<MachineOperand> &Pred2) const {
const MachineOperand &PredReg1 = Pred1[0];
const MachineOperand &PredReg2 = Pred2[0];
if (PredReg1.getReg() != PredReg2.getReg())
return false;
const MachineOperand &PredOp1 = Pred1[1];
const MachineOperand &PredOp2 = Pred2[1];
if (PredOp1.getImm() != PredOp2.getImm())
return false;
return true;
}
bool PTXInstrInfo::
DefinesPredicate(MachineInstr *MI,
std::vector<MachineOperand> &Pred) const {
// If an instruction sets a predicate register, it defines a predicate.
// TODO supprot 5-operand format of setp instruction
if (MI->getNumOperands() < 1)
return false;
const MachineOperand &MO = MI->getOperand(0);
if (!MO.isReg() || RI.getRegClass(MO.getReg()) != &PTX::RegPredRegClass)
return false;
Pred.push_back(MO);
Pred.push_back(MachineOperand::CreateImm(PTX::PRED_NORMAL));
return true;
}
// branch support
bool PTXInstrInfo::
AnalyzeBranch(MachineBasicBlock &MBB,
MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const {
// TODO implement cases when AllowModify is true
if (MBB.empty())
return true;
MachineBasicBlock::const_iterator iter = MBB.end();
const MachineInstr& instLast1 = *--iter;
const TargetInstrDesc &desc1 = instLast1.getDesc();
// for special case that MBB has only 1 instruction
const bool IsSizeOne = MBB.size() == 1;
// if IsSizeOne is true, *--iter and instLast2 are invalid
// we put a dummy value in instLast2 and desc2 since they are used
const MachineInstr& instLast2 = IsSizeOne ? instLast1 : *--iter;
const TargetInstrDesc &desc2 = IsSizeOne ? desc1 : instLast2.getDesc();
DEBUG(dbgs() << "\n");
DEBUG(dbgs() << "AnalyzeBranch: opcode: " << instLast1.getOpcode() << "\n");
DEBUG(dbgs() << "AnalyzeBranch: MBB: " << MBB.getName().str() << "\n");
DEBUG(dbgs() << "AnalyzeBranch: TBB: " << TBB << "\n");
DEBUG(dbgs() << "AnalyzeBranch: FBB: " << FBB << "\n");
// this block ends with no branches
if (!IsAnyKindOfBranch(instLast1)) {
DEBUG(dbgs() << "AnalyzeBranch: ends with no branch\n");
return false;
}
// this block ends with only an unconditional branch
if (desc1.isUnconditionalBranch() &&
// when IsSizeOne is true, it "absorbs" the evaluation of instLast2
(IsSizeOne || !IsAnyKindOfBranch(instLast2))) {
DEBUG(dbgs() << "AnalyzeBranch: ends with only uncond branch\n");
TBB = GetBranchTarget(instLast1);
return false;
}
// this block ends with a conditional branch and
// it falls through to a successor block
if (desc1.isConditionalBranch() &&
IsAnySuccessorAlsoLayoutSuccessor(MBB)) {
DEBUG(dbgs() << "AnalyzeBranch: ends with cond branch and fall through\n");
TBB = GetBranchTarget(instLast1);
int i = instLast1.findFirstPredOperandIdx();
Cond.push_back(instLast1.getOperand(i));
Cond.push_back(instLast1.getOperand(i+1));
return false;
}
// when IsSizeOne is true, we are done
if (IsSizeOne)
return true;
// this block ends with a conditional branch
// followed by an unconditional branch
if (desc2.isConditionalBranch() &&
desc1.isUnconditionalBranch()) {
DEBUG(dbgs() << "AnalyzeBranch: ends with cond and uncond branch\n");
TBB = GetBranchTarget(instLast2);
FBB = GetBranchTarget(instLast1);
int i = instLast2.findFirstPredOperandIdx();
Cond.push_back(instLast2.getOperand(i));
Cond.push_back(instLast2.getOperand(i+1));
return false;
}
// branch cannot be understood
DEBUG(dbgs() << "AnalyzeBranch: cannot be understood\n");
return true;
}
unsigned PTXInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
unsigned count = 0;
while (!MBB.empty())
if (IsAnyKindOfBranch(MBB.back())) {
MBB.pop_back();
++count;
} else
break;
DEBUG(dbgs() << "RemoveBranch: MBB: " << MBB.getName().str() << "\n");
DEBUG(dbgs() << "RemoveBranch: remove " << count << " branch inst\n");
return count;
}
unsigned PTXInstrInfo::
InsertBranch(MachineBasicBlock &MBB,
MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond,
DebugLoc DL) const {
DEBUG(dbgs() << "InsertBranch: MBB: " << MBB.getName().str() << "\n");
DEBUG(if (TBB) dbgs() << "InsertBranch: TBB: " << TBB->getName().str()
<< "\n";
else dbgs() << "InsertBranch: TBB: (NULL)\n");
DEBUG(if (FBB) dbgs() << "InsertBranch: FBB: " << FBB->getName().str()
<< "\n";
else dbgs() << "InsertBranch: FBB: (NULL)\n");
DEBUG(dbgs() << "InsertBranch: Cond size: " << Cond.size() << "\n");
assert(TBB && "TBB is NULL");
if (FBB) {
BuildMI(&MBB, DL, get(PTX::BRAdp))
.addMBB(TBB).addReg(Cond[0].getReg()).addImm(Cond[1].getImm());
BuildMI(&MBB, DL, get(PTX::BRAd))
.addMBB(FBB).addReg(PTX::NoRegister).addImm(PTX::PRED_NORMAL);
return 2;
} else if (Cond.size()) {
BuildMI(&MBB, DL, get(PTX::BRAdp))
.addMBB(TBB).addReg(Cond[0].getReg()).addImm(Cond[1].getImm());
return 1;
} else {
BuildMI(&MBB, DL, get(PTX::BRAd))
.addMBB(TBB).addReg(PTX::NoRegister).addImm(PTX::PRED_NORMAL);
return 1;
}
}
// Memory operand folding for spills
void PTXInstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MII,
unsigned SrcReg, bool isKill, int FrameIdx,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const {
MachineInstr& MI = *MII;
DebugLoc DL = MI.getDebugLoc();
DEBUG(dbgs() << "storeRegToStackSlot: " << MI);
int OpCode;
// Select the appropriate opcode based on the register class
if (RC == PTX::RegI8RegisterClass) {
OpCode = PTX::STACKSTOREI8;
} else if (RC == PTX::RegI16RegisterClass) {
OpCode = PTX::STACKSTOREI16;
} else if (RC == PTX::RegI32RegisterClass) {
OpCode = PTX::STACKSTOREI32;
} else if (RC == PTX::RegI64RegisterClass) {
OpCode = PTX::STACKSTOREI32;
} else if (RC == PTX::RegF32RegisterClass) {
OpCode = PTX::STACKSTOREF32;
} else if (RC == PTX::RegF64RegisterClass) {
OpCode = PTX::STACKSTOREF64;
} else {
llvm_unreachable("Unknown PTX register class!");
}
// Build the store instruction (really a mov)
MachineInstrBuilder MIB = BuildMI(MBB, MII, DL, get(OpCode));
MIB.addFrameIndex(FrameIdx);
MIB.addReg(SrcReg);
AddDefaultPredicate(MIB);
}
void PTXInstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MII,
unsigned DestReg, int FrameIdx,
const TargetRegisterClass *RC,
const TargetRegisterInfo *TRI) const {
MachineInstr& MI = *MII;
DebugLoc DL = MI.getDebugLoc();
DEBUG(dbgs() << "loadRegToStackSlot: " << MI);
int OpCode;
// Select the appropriate opcode based on the register class
if (RC == PTX::RegI8RegisterClass) {
OpCode = PTX::STACKLOADI8;
} else if (RC == PTX::RegI16RegisterClass) {
OpCode = PTX::STACKLOADI16;
} else if (RC == PTX::RegI32RegisterClass) {
OpCode = PTX::STACKLOADI32;
} else if (RC == PTX::RegI64RegisterClass) {
OpCode = PTX::STACKLOADI32;
} else if (RC == PTX::RegF32RegisterClass) {
OpCode = PTX::STACKLOADF32;
} else if (RC == PTX::RegF64RegisterClass) {
OpCode = PTX::STACKLOADF64;
} else {
llvm_unreachable("Unknown PTX register class!");
}
// Build the load instruction (really a mov)
MachineInstrBuilder MIB = BuildMI(MBB, MII, DL, get(OpCode));
MIB.addReg(DestReg);
MIB.addFrameIndex(FrameIdx);
AddDefaultPredicate(MIB);
}
// static helper routines
MachineSDNode *PTXInstrInfo::
GetPTXMachineNode(SelectionDAG *DAG, unsigned Opcode,
DebugLoc dl, EVT VT, SDValue Op1) {
SDValue predReg = DAG->getRegister(PTX::NoRegister, MVT::i1);
SDValue predOp = DAG->getTargetConstant(PTX::PRED_NORMAL, MVT::i32);
SDValue ops[] = { Op1, predReg, predOp };
return DAG->getMachineNode(Opcode, dl, VT, ops, array_lengthof(ops));
}
MachineSDNode *PTXInstrInfo::
GetPTXMachineNode(SelectionDAG *DAG, unsigned Opcode,
DebugLoc dl, EVT VT, SDValue Op1, SDValue Op2) {
SDValue predReg = DAG->getRegister(PTX::NoRegister, MVT::i1);
SDValue predOp = DAG->getTargetConstant(PTX::PRED_NORMAL, MVT::i32);
SDValue ops[] = { Op1, Op2, predReg, predOp };
return DAG->getMachineNode(Opcode, dl, VT, ops, array_lengthof(ops));
}
void PTXInstrInfo::AddDefaultPredicate(MachineInstr *MI) {
if (MI->findFirstPredOperandIdx() == -1) {
MI->addOperand(MachineOperand::CreateReg(PTX::NoRegister, /*IsDef=*/false));
MI->addOperand(MachineOperand::CreateImm(PTX::PRED_NORMAL));
}
}
bool PTXInstrInfo::IsAnyKindOfBranch(const MachineInstr& inst) {
const TargetInstrDesc &desc = inst.getDesc();
return desc.isTerminator() || desc.isBranch() || desc.isIndirectBranch();
}
bool PTXInstrInfo::
IsAnySuccessorAlsoLayoutSuccessor(const MachineBasicBlock& MBB) {
for (MachineBasicBlock::const_succ_iterator
i = MBB.succ_begin(), e = MBB.succ_end(); i != e; ++i)
if (MBB.isLayoutSuccessor((const MachineBasicBlock*) &*i))
return true;
return false;
}
MachineBasicBlock *PTXInstrInfo::GetBranchTarget(const MachineInstr& inst) {
// FIXME So far all branch instructions put destination in 1st operand
const MachineOperand& target = inst.getOperand(0);
assert(target.isMBB() && "FIXME: detect branch target operand");
return target.getMBB();
}