llvm-6502/lib/Target/CellSPU/SPUInstrInfo.cpp
Torok Edwin dac237e182 Implement changes from Chris's feedback.
Finish converting lib/Target.


git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@75043 91177308-0d34-0410-b5e6-96231b3b80d8
2009-07-08 20:53:28 +00:00

692 lines
22 KiB
C++

//===- SPUInstrInfo.cpp - Cell SPU 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 Cell SPU implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "SPURegisterNames.h"
#include "SPUInstrInfo.h"
#include "SPUInstrBuilder.h"
#include "SPUTargetMachine.h"
#include "SPUGenInstrInfo.inc"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/Support/Streams.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
using namespace llvm;
namespace {
//! Predicate for an unconditional branch instruction
inline bool isUncondBranch(const MachineInstr *I) {
unsigned opc = I->getOpcode();
return (opc == SPU::BR
|| opc == SPU::BRA
|| opc == SPU::BI);
}
//! Predicate for a conditional branch instruction
inline bool isCondBranch(const MachineInstr *I) {
unsigned opc = I->getOpcode();
return (opc == SPU::BRNZr32
|| opc == SPU::BRNZv4i32
|| opc == SPU::BRZr32
|| opc == SPU::BRZv4i32
|| opc == SPU::BRHNZr16
|| opc == SPU::BRHNZv8i16
|| opc == SPU::BRHZr16
|| opc == SPU::BRHZv8i16);
}
}
SPUInstrInfo::SPUInstrInfo(SPUTargetMachine &tm)
: TargetInstrInfoImpl(SPUInsts, sizeof(SPUInsts)/sizeof(SPUInsts[0])),
TM(tm),
RI(*TM.getSubtargetImpl(), *this)
{ /* NOP */ }
bool
SPUInstrInfo::isMoveInstr(const MachineInstr& MI,
unsigned& sourceReg,
unsigned& destReg,
unsigned& SrcSR, unsigned& DstSR) const {
SrcSR = DstSR = 0; // No sub-registers.
switch (MI.getOpcode()) {
default:
break;
case SPU::ORIv4i32:
case SPU::ORIr32:
case SPU::ORHIv8i16:
case SPU::ORHIr16:
case SPU::ORHIi8i16:
case SPU::ORBIv16i8:
case SPU::ORBIr8:
case SPU::ORIi16i32:
case SPU::ORIi8i32:
case SPU::AHIvec:
case SPU::AHIr16:
case SPU::AIv4i32:
assert(MI.getNumOperands() == 3 &&
MI.getOperand(0).isReg() &&
MI.getOperand(1).isReg() &&
MI.getOperand(2).isImm() &&
"invalid SPU ORI/ORHI/ORBI/AHI/AI/SFI/SFHI instruction!");
if (MI.getOperand(2).getImm() == 0) {
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
break;
case SPU::AIr32:
assert(MI.getNumOperands() == 3 &&
"wrong number of operands to AIr32");
if (MI.getOperand(0).isReg() &&
MI.getOperand(1).isReg() &&
(MI.getOperand(2).isImm() &&
MI.getOperand(2).getImm() == 0)) {
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
break;
case SPU::LRr8:
case SPU::LRr16:
case SPU::LRr32:
case SPU::LRf32:
case SPU::LRr64:
case SPU::LRf64:
case SPU::LRr128:
case SPU::LRv16i8:
case SPU::LRv8i16:
case SPU::LRv4i32:
case SPU::LRv4f32:
case SPU::LRv2i64:
case SPU::LRv2f64:
case SPU::ORv16i8_i8:
case SPU::ORv8i16_i16:
case SPU::ORv4i32_i32:
case SPU::ORv2i64_i64:
case SPU::ORv4f32_f32:
case SPU::ORv2f64_f64:
case SPU::ORi8_v16i8:
case SPU::ORi16_v8i16:
case SPU::ORi32_v4i32:
case SPU::ORi64_v2i64:
case SPU::ORf32_v4f32:
case SPU::ORf64_v2f64:
/*
case SPU::ORi128_r64:
case SPU::ORi128_f64:
case SPU::ORi128_r32:
case SPU::ORi128_f32:
case SPU::ORi128_r16:
case SPU::ORi128_r8:
*/
case SPU::ORi128_vec:
/*
case SPU::ORr64_i128:
case SPU::ORf64_i128:
case SPU::ORr32_i128:
case SPU::ORf32_i128:
case SPU::ORr16_i128:
case SPU::ORr8_i128:
*/
case SPU::ORvec_i128:
/*
case SPU::ORr16_r32:
case SPU::ORr8_r32:
case SPU::ORf32_r32:
case SPU::ORr32_f32:
case SPU::ORr32_r16:
case SPU::ORr32_r8:
case SPU::ORr16_r64:
case SPU::ORr8_r64:
case SPU::ORr64_r16:
case SPU::ORr64_r8:
*/
case SPU::ORr64_r32:
case SPU::ORr32_r64:
case SPU::ORf32_r32:
case SPU::ORr32_f32:
case SPU::ORf64_r64:
case SPU::ORr64_f64: {
assert(MI.getNumOperands() == 2 &&
MI.getOperand(0).isReg() &&
MI.getOperand(1).isReg() &&
"invalid SPU OR<type>_<vec> or LR instruction!");
if (MI.getOperand(0).getReg() == MI.getOperand(1).getReg()) {
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
break;
}
case SPU::ORv16i8:
case SPU::ORv8i16:
case SPU::ORv4i32:
case SPU::ORv2i64:
case SPU::ORr8:
case SPU::ORr16:
case SPU::ORr32:
case SPU::ORr64:
case SPU::ORr128:
case SPU::ORf32:
case SPU::ORf64:
assert(MI.getNumOperands() == 3 &&
MI.getOperand(0).isReg() &&
MI.getOperand(1).isReg() &&
MI.getOperand(2).isReg() &&
"invalid SPU OR(vec|r32|r64|gprc) instruction!");
if (MI.getOperand(1).getReg() == MI.getOperand(2).getReg()) {
sourceReg = MI.getOperand(1).getReg();
destReg = MI.getOperand(0).getReg();
return true;
}
break;
}
return false;
}
unsigned
SPUInstrInfo::isLoadFromStackSlot(const MachineInstr *MI,
int &FrameIndex) const {
switch (MI->getOpcode()) {
default: break;
case SPU::LQDv16i8:
case SPU::LQDv8i16:
case SPU::LQDv4i32:
case SPU::LQDv4f32:
case SPU::LQDv2f64:
case SPU::LQDr128:
case SPU::LQDr64:
case SPU::LQDr32:
case SPU::LQDr16: {
const MachineOperand MOp1 = MI->getOperand(1);
const MachineOperand MOp2 = MI->getOperand(2);
if (MOp1.isImm() && MOp2.isFI()) {
FrameIndex = MOp2.getIndex();
return MI->getOperand(0).getReg();
}
break;
}
}
return 0;
}
unsigned
SPUInstrInfo::isStoreToStackSlot(const MachineInstr *MI,
int &FrameIndex) const {
switch (MI->getOpcode()) {
default: break;
case SPU::STQDv16i8:
case SPU::STQDv8i16:
case SPU::STQDv4i32:
case SPU::STQDv4f32:
case SPU::STQDv2f64:
case SPU::STQDr128:
case SPU::STQDr64:
case SPU::STQDr32:
case SPU::STQDr16:
case SPU::STQDr8: {
const MachineOperand MOp1 = MI->getOperand(1);
const MachineOperand MOp2 = MI->getOperand(2);
if (MOp1.isImm() && MOp2.isFI()) {
FrameIndex = MOp2.getIndex();
return MI->getOperand(0).getReg();
}
break;
}
}
return 0;
}
bool SPUInstrInfo::copyRegToReg(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, unsigned SrcReg,
const TargetRegisterClass *DestRC,
const TargetRegisterClass *SrcRC) const
{
// We support cross register class moves for our aliases, such as R3 in any
// reg class to any other reg class containing R3. This is required because
// we instruction select bitconvert i64 -> f64 as a noop for example, so our
// types have no specific meaning.
DebugLoc DL = DebugLoc::getUnknownLoc();
if (MI != MBB.end()) DL = MI->getDebugLoc();
if (DestRC == SPU::R8CRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRr8), DestReg).addReg(SrcReg);
} else if (DestRC == SPU::R16CRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRr16), DestReg).addReg(SrcReg);
} else if (DestRC == SPU::R32CRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRr32), DestReg).addReg(SrcReg);
} else if (DestRC == SPU::R32FPRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRf32), DestReg).addReg(SrcReg);
} else if (DestRC == SPU::R64CRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRr64), DestReg).addReg(SrcReg);
} else if (DestRC == SPU::R64FPRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRf64), DestReg).addReg(SrcReg);
} else if (DestRC == SPU::GPRCRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRr128), DestReg).addReg(SrcReg);
} else if (DestRC == SPU::VECREGRegisterClass) {
BuildMI(MBB, MI, DL, get(SPU::LRv16i8), DestReg).addReg(SrcReg);
} else {
// Attempt to copy unknown/unsupported register class!
return false;
}
return true;
}
void
SPUInstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned SrcReg, bool isKill, int FrameIdx,
const TargetRegisterClass *RC) const
{
unsigned opc;
bool isValidFrameIdx = (FrameIdx < SPUFrameInfo::maxFrameOffset());
if (RC == SPU::GPRCRegisterClass) {
opc = (isValidFrameIdx ? SPU::STQDr128 : SPU::STQXr128);
} else if (RC == SPU::R64CRegisterClass) {
opc = (isValidFrameIdx ? SPU::STQDr64 : SPU::STQXr64);
} else if (RC == SPU::R64FPRegisterClass) {
opc = (isValidFrameIdx ? SPU::STQDr64 : SPU::STQXr64);
} else if (RC == SPU::R32CRegisterClass) {
opc = (isValidFrameIdx ? SPU::STQDr32 : SPU::STQXr32);
} else if (RC == SPU::R32FPRegisterClass) {
opc = (isValidFrameIdx ? SPU::STQDr32 : SPU::STQXr32);
} else if (RC == SPU::R16CRegisterClass) {
opc = (isValidFrameIdx ? SPU::STQDr16 : SPU::STQXr16);
} else if (RC == SPU::R8CRegisterClass) {
opc = (isValidFrameIdx ? SPU::STQDr8 : SPU::STQXr8);
} else if (RC == SPU::VECREGRegisterClass) {
opc = (isValidFrameIdx) ? SPU::STQDv16i8 : SPU::STQXv16i8;
} else {
LLVM_UNREACHABLE("Unknown regclass!");
}
DebugLoc DL = DebugLoc::getUnknownLoc();
if (MI != MBB.end()) DL = MI->getDebugLoc();
addFrameReference(BuildMI(MBB, MI, DL, get(opc))
.addReg(SrcReg, getKillRegState(isKill)), FrameIdx);
}
void SPUInstrInfo::storeRegToAddr(MachineFunction &MF, unsigned SrcReg,
bool isKill,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs) const {
llvm_report_error("storeRegToAddr() invoked!");
if (Addr[0].isFI()) {
/* do what storeRegToStackSlot does here */
} else {
unsigned Opc = 0;
if (RC == SPU::GPRCRegisterClass) {
/* Opc = PPC::STW; */
} else if (RC == SPU::R16CRegisterClass) {
/* Opc = PPC::STD; */
} else if (RC == SPU::R32CRegisterClass) {
/* Opc = PPC::STFD; */
} else if (RC == SPU::R32FPRegisterClass) {
/* Opc = PPC::STFD; */
} else if (RC == SPU::R64FPRegisterClass) {
/* Opc = PPC::STFS; */
} else if (RC == SPU::VECREGRegisterClass) {
/* Opc = PPC::STVX; */
} else {
LLVM_UNREACHABLE("Unknown regclass!");
}
DebugLoc DL = DebugLoc::getUnknownLoc();
MachineInstrBuilder MIB = BuildMI(MF, DL, get(Opc))
.addReg(SrcReg, getKillRegState(isKill));
for (unsigned i = 0, e = Addr.size(); i != e; ++i)
MIB.addOperand(Addr[i]);
NewMIs.push_back(MIB);
}
}
void
SPUInstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI,
unsigned DestReg, int FrameIdx,
const TargetRegisterClass *RC) const
{
unsigned opc;
bool isValidFrameIdx = (FrameIdx < SPUFrameInfo::maxFrameOffset());
if (RC == SPU::GPRCRegisterClass) {
opc = (isValidFrameIdx ? SPU::LQDr128 : SPU::LQXr128);
} else if (RC == SPU::R64CRegisterClass) {
opc = (isValidFrameIdx ? SPU::LQDr64 : SPU::LQXr64);
} else if (RC == SPU::R64FPRegisterClass) {
opc = (isValidFrameIdx ? SPU::LQDr64 : SPU::LQXr64);
} else if (RC == SPU::R32CRegisterClass) {
opc = (isValidFrameIdx ? SPU::LQDr32 : SPU::LQXr32);
} else if (RC == SPU::R32FPRegisterClass) {
opc = (isValidFrameIdx ? SPU::LQDr32 : SPU::LQXr32);
} else if (RC == SPU::R16CRegisterClass) {
opc = (isValidFrameIdx ? SPU::LQDr16 : SPU::LQXr16);
} else if (RC == SPU::R8CRegisterClass) {
opc = (isValidFrameIdx ? SPU::LQDr8 : SPU::LQXr8);
} else if (RC == SPU::VECREGRegisterClass) {
opc = (isValidFrameIdx) ? SPU::LQDv16i8 : SPU::LQXv16i8;
} else {
LLVM_UNREACHABLE("Unknown regclass in loadRegFromStackSlot!");
}
DebugLoc DL = DebugLoc::getUnknownLoc();
if (MI != MBB.end()) DL = MI->getDebugLoc();
addFrameReference(BuildMI(MBB, MI, DL, get(opc), DestReg), FrameIdx);
}
/*!
\note We are really pessimistic here about what kind of a load we're doing.
*/
void SPUInstrInfo::loadRegFromAddr(MachineFunction &MF, unsigned DestReg,
SmallVectorImpl<MachineOperand> &Addr,
const TargetRegisterClass *RC,
SmallVectorImpl<MachineInstr*> &NewMIs)
const {
llvm_report_error("loadRegToAddr() invoked!");
if (Addr[0].isFI()) {
/* do what loadRegFromStackSlot does here... */
} else {
unsigned Opc = 0;
if (RC == SPU::R8CRegisterClass) {
/* do brilliance here */
} else if (RC == SPU::R16CRegisterClass) {
/* Opc = PPC::LWZ; */
} else if (RC == SPU::R32CRegisterClass) {
/* Opc = PPC::LD; */
} else if (RC == SPU::R32FPRegisterClass) {
/* Opc = PPC::LFD; */
} else if (RC == SPU::R64FPRegisterClass) {
/* Opc = PPC::LFS; */
} else if (RC == SPU::VECREGRegisterClass) {
/* Opc = PPC::LVX; */
} else if (RC == SPU::GPRCRegisterClass) {
/* Opc = something else! */
} else {
LLVM_UNREACHABLE("Unknown regclass!");
}
DebugLoc DL = DebugLoc::getUnknownLoc();
MachineInstrBuilder MIB = BuildMI(MF, DL, get(Opc), DestReg);
for (unsigned i = 0, e = Addr.size(); i != e; ++i)
MIB.addOperand(Addr[i]);
NewMIs.push_back(MIB);
}
}
//! Return true if the specified load or store can be folded
bool
SPUInstrInfo::canFoldMemoryOperand(const MachineInstr *MI,
const SmallVectorImpl<unsigned> &Ops) const {
if (Ops.size() != 1) return false;
// Make sure this is a reg-reg copy.
unsigned Opc = MI->getOpcode();
switch (Opc) {
case SPU::ORv16i8:
case SPU::ORv8i16:
case SPU::ORv4i32:
case SPU::ORv2i64:
case SPU::ORr8:
case SPU::ORr16:
case SPU::ORr32:
case SPU::ORr64:
case SPU::ORf32:
case SPU::ORf64:
if (MI->getOperand(1).getReg() == MI->getOperand(2).getReg())
return true;
break;
}
return false;
}
/// foldMemoryOperand - SPU, like PPC, can only fold spills into
/// copy instructions, turning them into load/store instructions.
MachineInstr *
SPUInstrInfo::foldMemoryOperandImpl(MachineFunction &MF,
MachineInstr *MI,
const SmallVectorImpl<unsigned> &Ops,
int FrameIndex) const
{
if (Ops.size() != 1) return 0;
unsigned OpNum = Ops[0];
unsigned Opc = MI->getOpcode();
MachineInstr *NewMI = 0;
switch (Opc) {
case SPU::ORv16i8:
case SPU::ORv8i16:
case SPU::ORv4i32:
case SPU::ORv2i64:
case SPU::ORr8:
case SPU::ORr16:
case SPU::ORr32:
case SPU::ORr64:
case SPU::ORf32:
case SPU::ORf64:
if (OpNum == 0) { // move -> store
unsigned InReg = MI->getOperand(1).getReg();
bool isKill = MI->getOperand(1).isKill();
bool isUndef = MI->getOperand(1).isUndef();
if (FrameIndex < SPUFrameInfo::maxFrameOffset()) {
MachineInstrBuilder MIB = BuildMI(MF, MI->getDebugLoc(),
get(SPU::STQDr32));
MIB.addReg(InReg, getKillRegState(isKill) | getUndefRegState(isUndef));
NewMI = addFrameReference(MIB, FrameIndex);
}
} else { // move -> load
unsigned OutReg = MI->getOperand(0).getReg();
bool isDead = MI->getOperand(0).isDead();
bool isUndef = MI->getOperand(0).isUndef();
MachineInstrBuilder MIB = BuildMI(MF, MI->getDebugLoc(), get(Opc));
MIB.addReg(OutReg, RegState::Define | getDeadRegState(isDead) |
getUndefRegState(isUndef));
Opc = (FrameIndex < SPUFrameInfo::maxFrameOffset())
? SPU::STQDr32 : SPU::STQXr32;
NewMI = addFrameReference(MIB, FrameIndex);
break;
}
}
return NewMI;
}
//! Branch analysis
/*!
\note This code was kiped from PPC. There may be more branch analysis for
CellSPU than what's currently done here.
*/
bool
SPUInstrInfo::AnalyzeBranch(MachineBasicBlock &MBB, MachineBasicBlock *&TBB,
MachineBasicBlock *&FBB,
SmallVectorImpl<MachineOperand> &Cond,
bool AllowModify) const {
// If the block has no terminators, it just falls into the block after it.
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin() || !isUnpredicatedTerminator(--I))
return false;
// Get the last instruction in the block.
MachineInstr *LastInst = I;
// If there is only one terminator instruction, process it.
if (I == MBB.begin() || !isUnpredicatedTerminator(--I)) {
if (isUncondBranch(LastInst)) {
TBB = LastInst->getOperand(0).getMBB();
return false;
} else if (isCondBranch(LastInst)) {
// Block ends with fall-through condbranch.
TBB = LastInst->getOperand(1).getMBB();
DEBUG(cerr << "Pushing LastInst: ");
DEBUG(LastInst->dump());
Cond.push_back(MachineOperand::CreateImm(LastInst->getOpcode()));
Cond.push_back(LastInst->getOperand(0));
return false;
}
// Otherwise, don't know what this is.
return true;
}
// Get the instruction before it if it's a terminator.
MachineInstr *SecondLastInst = I;
// If there are three terminators, we don't know what sort of block this is.
if (SecondLastInst && I != MBB.begin() &&
isUnpredicatedTerminator(--I))
return true;
// If the block ends with a conditional and unconditional branch, handle it.
if (isCondBranch(SecondLastInst) && isUncondBranch(LastInst)) {
TBB = SecondLastInst->getOperand(1).getMBB();
DEBUG(cerr << "Pushing SecondLastInst: ");
DEBUG(SecondLastInst->dump());
Cond.push_back(MachineOperand::CreateImm(SecondLastInst->getOpcode()));
Cond.push_back(SecondLastInst->getOperand(0));
FBB = LastInst->getOperand(0).getMBB();
return false;
}
// If the block ends with two unconditional branches, handle it. The second
// one is not executed, so remove it.
if (isUncondBranch(SecondLastInst) && isUncondBranch(LastInst)) {
TBB = SecondLastInst->getOperand(0).getMBB();
I = LastInst;
if (AllowModify)
I->eraseFromParent();
return false;
}
// Otherwise, can't handle this.
return true;
}
unsigned
SPUInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin())
return 0;
--I;
if (!isCondBranch(I) && !isUncondBranch(I))
return 0;
// Remove the first branch.
DEBUG(cerr << "Removing branch: ");
DEBUG(I->dump());
I->eraseFromParent();
I = MBB.end();
if (I == MBB.begin())
return 1;
--I;
if (!(isCondBranch(I) || isUncondBranch(I)))
return 1;
// Remove the second branch.
DEBUG(cerr << "Removing second branch: ");
DEBUG(I->dump());
I->eraseFromParent();
return 2;
}
unsigned
SPUInstrInfo::InsertBranch(MachineBasicBlock &MBB, MachineBasicBlock *TBB,
MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond) const {
// FIXME this should probably have a DebugLoc argument
DebugLoc dl = DebugLoc::getUnknownLoc();
// Shouldn't be a fall through.
assert(TBB && "InsertBranch must not be told to insert a fallthrough");
assert((Cond.size() == 2 || Cond.size() == 0) &&
"SPU branch conditions have two components!");
// One-way branch.
if (FBB == 0) {
if (Cond.empty()) {
// Unconditional branch
MachineInstrBuilder MIB = BuildMI(&MBB, dl, get(SPU::BR));
MIB.addMBB(TBB);
DEBUG(cerr << "Inserted one-way uncond branch: ");
DEBUG((*MIB).dump());
} else {
// Conditional branch
MachineInstrBuilder MIB = BuildMI(&MBB, dl, get(Cond[0].getImm()));
MIB.addReg(Cond[1].getReg()).addMBB(TBB);
DEBUG(cerr << "Inserted one-way cond branch: ");
DEBUG((*MIB).dump());
}
return 1;
} else {
MachineInstrBuilder MIB = BuildMI(&MBB, dl, get(Cond[0].getImm()));
MachineInstrBuilder MIB2 = BuildMI(&MBB, dl, get(SPU::BR));
// Two-way Conditional Branch.
MIB.addReg(Cond[1].getReg()).addMBB(TBB);
MIB2.addMBB(FBB);
DEBUG(cerr << "Inserted conditional branch: ");
DEBUG((*MIB).dump());
DEBUG(cerr << "part 2: ");
DEBUG((*MIB2).dump());
return 2;
}
}
bool
SPUInstrInfo::BlockHasNoFallThrough(const MachineBasicBlock &MBB) const {
return (!MBB.empty() && isUncondBranch(&MBB.back()));
}
//! Reverses a branch's condition, returning false on success.
bool
SPUInstrInfo::ReverseBranchCondition(SmallVectorImpl<MachineOperand> &Cond)
const {
// Pretty brainless way of inverting the condition, but it works, considering
// there are only two conditions...
static struct {
unsigned Opc; //! The incoming opcode
unsigned RevCondOpc; //! The reversed condition opcode
} revconds[] = {
{ SPU::BRNZr32, SPU::BRZr32 },
{ SPU::BRNZv4i32, SPU::BRZv4i32 },
{ SPU::BRZr32, SPU::BRNZr32 },
{ SPU::BRZv4i32, SPU::BRNZv4i32 },
{ SPU::BRHNZr16, SPU::BRHZr16 },
{ SPU::BRHNZv8i16, SPU::BRHZv8i16 },
{ SPU::BRHZr16, SPU::BRHNZr16 },
{ SPU::BRHZv8i16, SPU::BRHNZv8i16 }
};
unsigned Opc = unsigned(Cond[0].getImm());
// Pretty dull mapping between the two conditions that SPU can generate:
for (int i = sizeof(revconds)/sizeof(revconds[0]) - 1; i >= 0; --i) {
if (revconds[i].Opc == Opc) {
Cond[0].setImm(revconds[i].RevCondOpc);
return false;
}
}
return true;
}