maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity
llvm-project/llvm/lib/Target/AMDGPU/AMDGPUInstructionSelector.cpp

1100 lines
37 KiB
C++
Raw Blame History

//===- AMDGPUInstructionSelector.cpp ----------------------------*- C++ -*-==//
//
// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
// See https://llvm.org/LICENSE.txt for license information.
// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
//
//===----------------------------------------------------------------------===//
/// \file
/// This file implements the targeting of the InstructionSelector class for
/// AMDGPU.
/// \todo This should be generated by TableGen.
//===----------------------------------------------------------------------===//
#include "AMDGPUInstructionSelector.h"
#include "AMDGPUInstrInfo.h"
#include "AMDGPURegisterBankInfo.h"
#include "AMDGPURegisterInfo.h"
#include "AMDGPUSubtarget.h"
#include "AMDGPUTargetMachine.h"
#include "SIMachineFunctionInfo.h"
#include "MCTargetDesc/AMDGPUMCTargetDesc.h"
#include "llvm/CodeGen/GlobalISel/InstructionSelector.h"
#include "llvm/CodeGen/GlobalISel/InstructionSelectorImpl.h"
#include "llvm/CodeGen/GlobalISel/Utils.h"
#include "llvm/CodeGen/MachineBasicBlock.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstr.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/Type.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#define DEBUG_TYPE "amdgpu-isel"
using namespace llvm;
#define GET_GLOBALISEL_IMPL
#define AMDGPUSubtarget GCNSubtarget
#include "AMDGPUGenGlobalISel.inc"
#undef GET_GLOBALISEL_IMPL
#undef AMDGPUSubtarget
AMDGPUInstructionSelector::AMDGPUInstructionSelector(
const GCNSubtarget &STI, const AMDGPURegisterBankInfo &RBI,
const AMDGPUTargetMachine &TM)
: InstructionSelector(), TII(*STI.getInstrInfo()),
TRI(*STI.getRegisterInfo()), RBI(RBI), TM(TM),
STI(STI),
EnableLateStructurizeCFG(AMDGPUTargetMachine::EnableLateStructurizeCFG),
#define GET_GLOBALISEL_PREDICATES_INIT
#include "AMDGPUGenGlobalISel.inc"
#undef GET_GLOBALISEL_PREDICATES_INIT
#define GET_GLOBALISEL_TEMPORARIES_INIT
#include "AMDGPUGenGlobalISel.inc"
#undef GET_GLOBALISEL_TEMPORARIES_INIT
{
}
const char *AMDGPUInstructionSelector::getName() { return DEBUG_TYPE; }
static bool isSCC(unsigned Reg, const MachineRegisterInfo &MRI) {
if (Reg == AMDGPU::SCC)
return true;
if (TargetRegisterInfo::isPhysicalRegister(Reg))
return false;
auto &RegClassOrBank = MRI.getRegClassOrRegBank(Reg);
const TargetRegisterClass *RC =
RegClassOrBank.dyn_cast<const TargetRegisterClass*>();
if (RC)
return RC->getID() == AMDGPU::SReg_32_XM0RegClassID &&
MRI.getType(Reg).getSizeInBits() == 1;
const RegisterBank *RB = RegClassOrBank.get<const RegisterBank *>();
return RB->getID() == AMDGPU::SCCRegBankID;
}
bool AMDGPUInstructionSelector::selectCOPY(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
I.setDesc(TII.get(TargetOpcode::COPY));
// Special case for COPY from the scc register bank. The scc register bank
// is modeled using 32-bit sgprs.
const MachineOperand &Src = I.getOperand(1);
unsigned SrcReg = Src.getReg();
if (!TargetRegisterInfo::isPhysicalRegister(SrcReg) && isSCC(SrcReg, MRI)) {
unsigned DstReg = TRI.getRegSizeInBits(I.getOperand(0).getReg(), MRI);
unsigned DstSize = TRI.getRegSizeInBits(DstReg, MRI);
// We have a copy from a 32-bit to 64-bit register. This happens
// when we are selecting scc->vcc copies.
if (DstSize == 64) {
const DebugLoc &DL = I.getDebugLoc();
BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CMP_NE_U32_e64), I.getOperand(0).getReg())
.addImm(0)
.addReg(SrcReg);
if (!MRI.getRegClassOrNull(SrcReg))
MRI.setRegClass(SrcReg, TRI.getConstrainedRegClassForOperand(Src, MRI));
I.eraseFromParent();
return true;
}
}
for (const MachineOperand &MO : I.operands()) {
if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
continue;
const TargetRegisterClass *RC =
TRI.getConstrainedRegClassForOperand(MO, MRI);
if (!RC)
continue;
RBI.constrainGenericRegister(MO.getReg(), *RC, MRI);
}
return true;
}
MachineOperand
AMDGPUInstructionSelector::getSubOperand64(MachineOperand &MO,
unsigned SubIdx) const {
MachineInstr *MI = MO.getParent();
MachineBasicBlock *BB = MO.getParent()->getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
unsigned DstReg = MRI.createVirtualRegister(&AMDGPU::SGPR_32RegClass);
if (MO.isReg()) {
unsigned ComposedSubIdx = TRI.composeSubRegIndices(MO.getSubReg(), SubIdx);
unsigned Reg = MO.getReg();
BuildMI(*BB, MI, MI->getDebugLoc(), TII.get(AMDGPU::COPY), DstReg)
.addReg(Reg, 0, ComposedSubIdx);
return MachineOperand::CreateReg(DstReg, MO.isDef(), MO.isImplicit(),
MO.isKill(), MO.isDead(), MO.isUndef(),
MO.isEarlyClobber(), 0, MO.isDebug(),
MO.isInternalRead());
}
assert(MO.isImm());
APInt Imm(64, MO.getImm());
switch (SubIdx) {
default:
llvm_unreachable("do not know to split immediate with this sub index.");
case AMDGPU::sub0:
return MachineOperand::CreateImm(Imm.getLoBits(32).getSExtValue());
case AMDGPU::sub1:
return MachineOperand::CreateImm(Imm.getHiBits(32).getSExtValue());
}
}
static int64_t getConstant(const MachineInstr *MI) {
return MI->getOperand(1).getCImm()->getSExtValue();
}
bool AMDGPUInstructionSelector::selectG_ADD(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
unsigned Size = RBI.getSizeInBits(I.getOperand(0).getReg(), MRI, TRI);
unsigned DstLo = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
unsigned DstHi = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
if (Size != 64)
return false;
DebugLoc DL = I.getDebugLoc();
MachineOperand Lo1(getSubOperand64(I.getOperand(1), AMDGPU::sub0));
MachineOperand Lo2(getSubOperand64(I.getOperand(2), AMDGPU::sub0));
BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADD_U32), DstLo)
.add(Lo1)
.add(Lo2);
MachineOperand Hi1(getSubOperand64(I.getOperand(1), AMDGPU::sub1));
MachineOperand Hi2(getSubOperand64(I.getOperand(2), AMDGPU::sub1));
BuildMI(*BB, &I, DL, TII.get(AMDGPU::S_ADDC_U32), DstHi)
.add(Hi1)
.add(Hi2);
BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), I.getOperand(0).getReg())
.addReg(DstLo)
.addImm(AMDGPU::sub0)
.addReg(DstHi)
.addImm(AMDGPU::sub1);
for (MachineOperand &MO : I.explicit_operands()) {
if (!MO.isReg() || TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
continue;
RBI.constrainGenericRegister(MO.getReg(), AMDGPU::SReg_64RegClass, MRI);
}
I.eraseFromParent();
return true;
}
bool AMDGPUInstructionSelector::selectG_EXTRACT(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
assert(I.getOperand(2).getImm() % 32 == 0);
unsigned SubReg = TRI.getSubRegFromChannel(I.getOperand(2).getImm() / 32);
const DebugLoc &DL = I.getDebugLoc();
MachineInstr *Copy = BuildMI(*BB, &I, DL, TII.get(TargetOpcode::COPY),
I.getOperand(0).getReg())
.addReg(I.getOperand(1).getReg(), 0, SubReg);
for (const MachineOperand &MO : Copy->operands()) {
const TargetRegisterClass *RC =
TRI.getConstrainedRegClassForOperand(MO, MRI);
if (!RC)
continue;
RBI.constrainGenericRegister(MO.getReg(), *RC, MRI);
}
I.eraseFromParent();
return true;
}
bool AMDGPUInstructionSelector::selectG_GEP(MachineInstr &I) const {
return selectG_ADD(I);
}
bool AMDGPUInstructionSelector::selectG_IMPLICIT_DEF(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
const MachineOperand &MO = I.getOperand(0);
// FIXME: Interface for getConstrainedRegClassForOperand needs work. The
// regbank check here is to know why getConstrainedRegClassForOperand failed.
const TargetRegisterClass *RC = TRI.getConstrainedRegClassForOperand(MO, MRI);
if ((!RC && !MRI.getRegBankOrNull(MO.getReg())) ||
(RC && RBI.constrainGenericRegister(MO.getReg(), *RC, MRI))) {
I.setDesc(TII.get(TargetOpcode::IMPLICIT_DEF));
return true;
}
return false;
}
bool AMDGPUInstructionSelector::selectG_INSERT(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
unsigned SubReg = TRI.getSubRegFromChannel(I.getOperand(3).getImm() / 32);
DebugLoc DL = I.getDebugLoc();
MachineInstr *Ins = BuildMI(*BB, &I, DL, TII.get(TargetOpcode::INSERT_SUBREG))
.addDef(I.getOperand(0).getReg())
.addReg(I.getOperand(1).getReg())
.addReg(I.getOperand(2).getReg())
.addImm(SubReg);
for (const MachineOperand &MO : Ins->operands()) {
if (!MO.isReg())
continue;
if (TargetRegisterInfo::isPhysicalRegister(MO.getReg()))
continue;
const TargetRegisterClass *RC =
TRI.getConstrainedRegClassForOperand(MO, MRI);
if (!RC)
continue;
RBI.constrainGenericRegister(MO.getReg(), *RC, MRI);
}
I.eraseFromParent();
return true;
}
bool AMDGPUInstructionSelector::selectG_INTRINSIC(MachineInstr &I,
CodeGenCoverage &CoverageInfo) const {
unsigned IntrinsicID = I.getOperand(I.getNumExplicitDefs()).getIntrinsicID();
switch (IntrinsicID) {
default:
break;
case Intrinsic::maxnum:
case Intrinsic::minnum:
case Intrinsic::amdgcn_cvt_pkrtz:
return selectImpl(I, CoverageInfo);
case Intrinsic::amdgcn_kernarg_segment_ptr: {
MachineFunction *MF = I.getParent()->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
const SIMachineFunctionInfo *MFI = MF->getInfo<SIMachineFunctionInfo>();
const ArgDescriptor *InputPtrReg;
const TargetRegisterClass *RC;
const DebugLoc &DL = I.getDebugLoc();
std::tie(InputPtrReg, RC)
= MFI->getPreloadedValue(AMDGPUFunctionArgInfo::KERNARG_SEGMENT_PTR);
if (!InputPtrReg)
report_fatal_error("missing kernarg segment ptr");
BuildMI(*I.getParent(), &I, DL, TII.get(AMDGPU::COPY))
.add(I.getOperand(0))
.addReg(MRI.getLiveInVirtReg(InputPtrReg->getRegister()));
I.eraseFromParent();
return true;
}
}
return false;
}
static unsigned getV_CMPOpcode(CmpInst::Predicate P, unsigned Size) {
assert(Size == 32 || Size == 64);
switch (P) {
default:
llvm_unreachable("Unknown condition code!");
case CmpInst::ICMP_NE:
return Size == 32 ? AMDGPU::V_CMP_NE_U32_e64 : AMDGPU::V_CMP_NE_U64_e64;
case CmpInst::ICMP_EQ:
return Size == 32 ? AMDGPU::V_CMP_EQ_U32_e64 : AMDGPU::V_CMP_EQ_U64_e64;
case CmpInst::ICMP_SGT:
return Size == 32 ? AMDGPU::V_CMP_GT_I32_e64 : AMDGPU::V_CMP_GT_I64_e64;
case CmpInst::ICMP_SGE:
return Size == 32 ? AMDGPU::V_CMP_GE_I32_e64 : AMDGPU::V_CMP_GE_I64_e64;
case CmpInst::ICMP_SLT:
return Size == 32 ? AMDGPU::V_CMP_LT_I32_e64 : AMDGPU::V_CMP_LT_I64_e64;
case CmpInst::ICMP_SLE:
return Size == 32 ? AMDGPU::V_CMP_LE_I32_e64 : AMDGPU::V_CMP_LE_I64_e64;
case CmpInst::ICMP_UGT:
return Size == 32 ? AMDGPU::V_CMP_GT_U32_e64 : AMDGPU::V_CMP_GT_U64_e64;
case CmpInst::ICMP_UGE:
return Size == 32 ? AMDGPU::V_CMP_GE_U32_e64 : AMDGPU::V_CMP_GE_U64_e64;
case CmpInst::ICMP_ULT:
return Size == 32 ? AMDGPU::V_CMP_LT_U32_e64 : AMDGPU::V_CMP_LT_U64_e64;
case CmpInst::ICMP_ULE:
return Size == 32 ? AMDGPU::V_CMP_LE_U32_e64 : AMDGPU::V_CMP_LE_U64_e64;
}
}
static unsigned getS_CMPOpcode(CmpInst::Predicate P, unsigned Size) {
// FIXME: VI supports 64-bit comparse.
assert(Size == 32);
switch (P) {
default:
llvm_unreachable("Unknown condition code!");
case CmpInst::ICMP_NE:
return AMDGPU::S_CMP_LG_U32;
case CmpInst::ICMP_EQ:
return AMDGPU::S_CMP_EQ_U32;
case CmpInst::ICMP_SGT:
return AMDGPU::S_CMP_GT_I32;
case CmpInst::ICMP_SGE:
return AMDGPU::S_CMP_GE_I32;
case CmpInst::ICMP_SLT:
return AMDGPU::S_CMP_LT_I32;
case CmpInst::ICMP_SLE:
return AMDGPU::S_CMP_LE_I32;
case CmpInst::ICMP_UGT:
return AMDGPU::S_CMP_GT_U32;
case CmpInst::ICMP_UGE:
return AMDGPU::S_CMP_GE_U32;
case CmpInst::ICMP_ULT:
return AMDGPU::S_CMP_LT_U32;
case CmpInst::ICMP_ULE:
return AMDGPU::S_CMP_LE_U32;
}
}
bool AMDGPUInstructionSelector::selectG_ICMP(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
DebugLoc DL = I.getDebugLoc();
unsigned SrcReg = I.getOperand(2).getReg();
unsigned Size = RBI.getSizeInBits(SrcReg, MRI, TRI);
// FIXME: VI supports 64-bit compares.
assert(Size == 32);
unsigned CCReg = I.getOperand(0).getReg();
if (isSCC(CCReg, MRI)) {
unsigned Opcode = getS_CMPOpcode((CmpInst::Predicate)I.getOperand(1).getPredicate(), Size);
MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode))
.add(I.getOperand(2))
.add(I.getOperand(3));
BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), CCReg)
.addReg(AMDGPU::SCC);
bool Ret =
constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI) &&
RBI.constrainGenericRegister(CCReg, AMDGPU::SReg_32RegClass, MRI);
I.eraseFromParent();
return Ret;
}
assert(Size == 32 || Size == 64);
unsigned Opcode = getV_CMPOpcode((CmpInst::Predicate)I.getOperand(1).getPredicate(), Size);
MachineInstr *ICmp = BuildMI(*BB, &I, DL, TII.get(Opcode),
I.getOperand(0).getReg())
.add(I.getOperand(2))
.add(I.getOperand(3));
RBI.constrainGenericRegister(ICmp->getOperand(0).getReg(),
AMDGPU::SReg_64RegClass, MRI);
bool Ret = constrainSelectedInstRegOperands(*ICmp, TII, TRI, RBI);
I.eraseFromParent();
return Ret;
}
static MachineInstr *
buildEXP(const TargetInstrInfo &TII, MachineInstr *Insert, unsigned Tgt,
unsigned Reg0, unsigned Reg1, unsigned Reg2, unsigned Reg3,
unsigned VM, bool Compr, unsigned Enabled, bool Done) {
const DebugLoc &DL = Insert->getDebugLoc();
MachineBasicBlock &BB = *Insert->getParent();
unsigned Opcode = Done ? AMDGPU::EXP_DONE : AMDGPU::EXP;
return BuildMI(BB, Insert, DL, TII.get(Opcode))
.addImm(Tgt)
.addReg(Reg0)
.addReg(Reg1)
.addReg(Reg2)
.addReg(Reg3)
.addImm(VM)
.addImm(Compr)
.addImm(Enabled);
}
bool AMDGPUInstructionSelector::selectG_INTRINSIC_W_SIDE_EFFECTS(
MachineInstr &I,
CodeGenCoverage &CoverageInfo) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
unsigned IntrinsicID = I.getOperand(0).getIntrinsicID();
switch (IntrinsicID) {
case Intrinsic::amdgcn_exp: {
int64_t Tgt = getConstant(MRI.getVRegDef(I.getOperand(1).getReg()));
int64_t Enabled = getConstant(MRI.getVRegDef(I.getOperand(2).getReg()));
int64_t Done = getConstant(MRI.getVRegDef(I.getOperand(7).getReg()));
int64_t VM = getConstant(MRI.getVRegDef(I.getOperand(8).getReg()));
MachineInstr *Exp = buildEXP(TII, &I, Tgt, I.getOperand(3).getReg(),
I.getOperand(4).getReg(),
I.getOperand(5).getReg(),
I.getOperand(6).getReg(),
VM, false, Enabled, Done);
I.eraseFromParent();
return constrainSelectedInstRegOperands(*Exp, TII, TRI, RBI);
}
case Intrinsic::amdgcn_exp_compr: {
const DebugLoc &DL = I.getDebugLoc();
int64_t Tgt = getConstant(MRI.getVRegDef(I.getOperand(1).getReg()));
int64_t Enabled = getConstant(MRI.getVRegDef(I.getOperand(2).getReg()));
unsigned Reg0 = I.getOperand(3).getReg();
unsigned Reg1 = I.getOperand(4).getReg();
unsigned Undef = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
int64_t Done = getConstant(MRI.getVRegDef(I.getOperand(5).getReg()));
int64_t VM = getConstant(MRI.getVRegDef(I.getOperand(6).getReg()));
BuildMI(*BB, &I, DL, TII.get(AMDGPU::IMPLICIT_DEF), Undef);
MachineInstr *Exp = buildEXP(TII, &I, Tgt, Reg0, Reg1, Undef, Undef, VM,
true, Enabled, Done);
I.eraseFromParent();
return constrainSelectedInstRegOperands(*Exp, TII, TRI, RBI);
}
}
return false;
}
bool AMDGPUInstructionSelector::selectG_SELECT(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
const DebugLoc &DL = I.getDebugLoc();
unsigned DstReg = I.getOperand(0).getReg();
unsigned Size = RBI.getSizeInBits(DstReg, MRI, TRI);
assert(Size == 32 || Size == 64);
const MachineOperand &CCOp = I.getOperand(1);
unsigned CCReg = CCOp.getReg();
if (isSCC(CCReg, MRI)) {
unsigned SelectOpcode = Size == 32 ? AMDGPU::S_CSELECT_B32 :
AMDGPU::S_CSELECT_B64;
MachineInstr *CopySCC = BuildMI(*BB, &I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
.addReg(CCReg);
// The generic constrainSelectedInstRegOperands doesn't work for the scc register
// bank, because it does not cover the register class that we used to represent
// for it. So we need to manually set the register class here.
if (!MRI.getRegClassOrNull(CCReg))
MRI.setRegClass(CCReg, TRI.getConstrainedRegClassForOperand(CCOp, MRI));
MachineInstr *Select = BuildMI(*BB, &I, DL, TII.get(SelectOpcode), DstReg)
.add(I.getOperand(2))
.add(I.getOperand(3));
bool Ret = constrainSelectedInstRegOperands(*Select, TII, TRI, RBI) |
constrainSelectedInstRegOperands(*CopySCC, TII, TRI, RBI);
I.eraseFromParent();
return Ret;
}
assert(Size == 32);
// FIXME: Support 64-bit select
MachineInstr *Select =
BuildMI(*BB, &I, DL, TII.get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
.addImm(0)
.add(I.getOperand(3))
.addImm(0)
.add(I.getOperand(2))
.add(I.getOperand(1));
bool Ret = constrainSelectedInstRegOperands(*Select, TII, TRI, RBI);
I.eraseFromParent();
return Ret;
}
bool AMDGPUInstructionSelector::selectG_STORE(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
DebugLoc DL = I.getDebugLoc();
unsigned StoreSize = RBI.getSizeInBits(I.getOperand(0).getReg(), MRI, TRI);
unsigned Opcode;
// FIXME: Select store instruction based on address space
switch (StoreSize) {
default:
return false;
case 32:
Opcode = AMDGPU::FLAT_STORE_DWORD;
break;
case 64:
Opcode = AMDGPU::FLAT_STORE_DWORDX2;
break;
case 96:
Opcode = AMDGPU::FLAT_STORE_DWORDX3;
break;
case 128:
Opcode = AMDGPU::FLAT_STORE_DWORDX4;
break;
}
MachineInstr *Flat = BuildMI(*BB, &I, DL, TII.get(Opcode))
.add(I.getOperand(1))
.add(I.getOperand(0))
.addImm(0) // offset
.addImm(0) // glc
.addImm(0) // slc
.addImm(0); // dlc
// Now that we selected an opcode, we need to constrain the register
// operands to use appropriate classes.
bool Ret = constrainSelectedInstRegOperands(*Flat, TII, TRI, RBI);
I.eraseFromParent();
return Ret;
}
static int sizeToSubRegIndex(unsigned Size) {
switch (Size) {
case 32:
return AMDGPU::sub0;
case 64:
return AMDGPU::sub0_sub1;
case 96:
return AMDGPU::sub0_sub1_sub2;
case 128:
return AMDGPU::sub0_sub1_sub2_sub3;
case 256:
return AMDGPU::sub0_sub1_sub2_sub3_sub4_sub5_sub6_sub7;
default:
if (Size < 32)
return AMDGPU::sub0;
if (Size > 256)
return -1;
return sizeToSubRegIndex(PowerOf2Ceil(Size));
}
}
bool AMDGPUInstructionSelector::selectG_TRUNC(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
unsigned DstReg = I.getOperand(0).getReg();
unsigned SrcReg = I.getOperand(1).getReg();
const LLT DstTy = MRI.getType(DstReg);
const LLT SrcTy = MRI.getType(SrcReg);
if (!DstTy.isScalar())
return false;
const RegisterBank *DstRB = RBI.getRegBank(DstReg, MRI, TRI);
const RegisterBank *SrcRB = RBI.getRegBank(SrcReg, MRI, TRI);
if (SrcRB != DstRB)
return false;
unsigned DstSize = DstTy.getSizeInBits();
unsigned SrcSize = SrcTy.getSizeInBits();
const TargetRegisterClass *SrcRC
= TRI.getRegClassForSizeOnBank(SrcSize, *SrcRB, MRI);
const TargetRegisterClass *DstRC
= TRI.getRegClassForSizeOnBank(DstSize, *DstRB, MRI);
if (SrcSize > 32) {
int SubRegIdx = sizeToSubRegIndex(DstSize);
if (SubRegIdx == -1)
return false;
// Deal with weird cases where the class only partially supports the subreg
// index.
SrcRC = TRI.getSubClassWithSubReg(SrcRC, SubRegIdx);
if (!SrcRC)
return false;
I.getOperand(1).setSubReg(SubRegIdx);
}
if (!RBI.constrainGenericRegister(SrcReg, *SrcRC, MRI) ||
!RBI.constrainGenericRegister(DstReg, *DstRC, MRI)) {
LLVM_DEBUG(dbgs() << "Failed to constrain G_TRUNC\n");
return false;
}
I.setDesc(TII.get(TargetOpcode::COPY));
return true;
}
bool AMDGPUInstructionSelector::selectG_SZA_EXT(MachineInstr &I) const {
bool Signed = I.getOpcode() == AMDGPU::G_SEXT;
const DebugLoc &DL = I.getDebugLoc();
MachineBasicBlock &MBB = *I.getParent();
MachineFunction &MF = *MBB.getParent();
MachineRegisterInfo &MRI = MF.getRegInfo();
const unsigned DstReg = I.getOperand(0).getReg();
const unsigned SrcReg = I.getOperand(1).getReg();
const LLT DstTy = MRI.getType(DstReg);
const LLT SrcTy = MRI.getType(SrcReg);
const LLT S1 = LLT::scalar(1);
const unsigned SrcSize = SrcTy.getSizeInBits();
const unsigned DstSize = DstTy.getSizeInBits();
if (!DstTy.isScalar())
return false;
const RegisterBank *SrcBank = RBI.getRegBank(SrcReg, MRI, TRI);
if (SrcBank->getID() == AMDGPU::SCCRegBankID) {
if (SrcTy != S1 || DstSize > 64) // Invalid
return false;
unsigned Opcode =
DstSize > 32 ? AMDGPU::S_CSELECT_B64 : AMDGPU::S_CSELECT_B32;
const TargetRegisterClass *DstRC =
DstSize > 32 ? &AMDGPU::SReg_64RegClass : &AMDGPU::SReg_32RegClass;
// FIXME: Create an extra copy to avoid incorrectly constraining the result
// of the scc producer.
unsigned TmpReg = MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
BuildMI(MBB, I, DL, TII.get(AMDGPU::COPY), TmpReg)
.addReg(SrcReg);
BuildMI(MBB, I, DL, TII.get(AMDGPU::COPY), AMDGPU::SCC)
.addReg(TmpReg);
// The instruction operands are backwards from what you would expect.
BuildMI(MBB, I, DL, TII.get(Opcode), DstReg)
.addImm(0)
.addImm(Signed ? -1 : 1);
return RBI.constrainGenericRegister(DstReg, *DstRC, MRI);
}
if (SrcBank->getID() == AMDGPU::VCCRegBankID && DstSize <= 32) {
if (SrcTy != S1) // Invalid
return false;
MachineInstr *ExtI =
BuildMI(MBB, I, DL, TII.get(AMDGPU::V_CNDMASK_B32_e64), DstReg)
.addImm(0) // src0_modifiers
.addImm(0) // src0
.addImm(0) // src1_modifiers
.addImm(Signed ? -1 : 1) // src1
.addUse(SrcReg);
return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
}
if (I.getOpcode() == AMDGPU::G_ANYEXT)
return selectCOPY(I);
if (SrcBank->getID() == AMDGPU::VGPRRegBankID && DstSize <= 32) {
// 64-bit should have been split up in RegBankSelect
//
// TODO: USE V_AND_B32 when the constant mask is an inline immediate for
// unsigned for smaller code size.
const unsigned BFE = Signed ? AMDGPU::V_BFE_I32 : AMDGPU::V_BFE_U32;
MachineInstr *ExtI =
BuildMI(MBB, I, DL, TII.get(BFE), DstReg)
.addReg(SrcReg)
.addImm(0) // Offset
.addImm(SrcSize); // Width
return constrainSelectedInstRegOperands(*ExtI, TII, TRI, RBI);
}
if (SrcBank->getID() == AMDGPU::SGPRRegBankID && DstSize <= 64) {
if (!RBI.constrainGenericRegister(SrcReg, AMDGPU::SReg_32RegClass, MRI))
return false;
if (Signed && DstSize == 32 && (SrcSize == 8 || SrcSize == 16)) {
const unsigned SextOpc = SrcSize == 8 ?
AMDGPU::S_SEXT_I32_I8 : AMDGPU::S_SEXT_I32_I16;
BuildMI(MBB, I, DL, TII.get(SextOpc), DstReg)
.addReg(SrcReg);
return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, MRI);
}
const unsigned BFE64 = Signed ? AMDGPU::S_BFE_I64 : AMDGPU::S_BFE_U64;
const unsigned BFE32 = Signed ? AMDGPU::S_BFE_I32 : AMDGPU::S_BFE_U32;
// Scalar BFE is encoded as S1[5:0] = offset, S1[22:16]= width.
if (DstSize > 32 && SrcSize <= 32) {
// We need a 64-bit register source, but the high bits don't matter.
unsigned ExtReg
= MRI.createVirtualRegister(&AMDGPU::SReg_64RegClass);
unsigned UndefReg
= MRI.createVirtualRegister(&AMDGPU::SReg_32RegClass);
BuildMI(MBB, I, DL, TII.get(AMDGPU::IMPLICIT_DEF), UndefReg);
BuildMI(MBB, I, DL, TII.get(AMDGPU::REG_SEQUENCE), ExtReg)
.addReg(SrcReg)
.addImm(AMDGPU::sub0)
.addReg(UndefReg)
.addImm(AMDGPU::sub1);
BuildMI(MBB, I, DL, TII.get(BFE64), DstReg)
.addReg(ExtReg)
.addImm(SrcSize << 16);
return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_64RegClass, MRI);
}
BuildMI(MBB, I, DL, TII.get(BFE32), DstReg)
.addReg(SrcReg)
.addImm(SrcSize << 16);
return RBI.constrainGenericRegister(DstReg, AMDGPU::SReg_32RegClass, MRI);
}
return false;
}
bool AMDGPUInstructionSelector::selectG_CONSTANT(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
MachineOperand &ImmOp = I.getOperand(1);
// The AMDGPU backend only supports Imm operands and not CImm or FPImm.
if (ImmOp.isFPImm()) {
const APInt &Imm = ImmOp.getFPImm()->getValueAPF().bitcastToAPInt();
ImmOp.ChangeToImmediate(Imm.getZExtValue());
} else if (ImmOp.isCImm()) {
ImmOp.ChangeToImmediate(ImmOp.getCImm()->getZExtValue());
}
unsigned DstReg = I.getOperand(0).getReg();
unsigned Size;
bool IsSgpr;
const RegisterBank *RB = MRI.getRegBankOrNull(I.getOperand(0).getReg());
if (RB) {
IsSgpr = RB->getID() == AMDGPU::SGPRRegBankID;
Size = MRI.getType(DstReg).getSizeInBits();
} else {
const TargetRegisterClass *RC = TRI.getRegClassForReg(MRI, DstReg);
IsSgpr = TRI.isSGPRClass(RC);
Size = TRI.getRegSizeInBits(*RC);
}
if (Size != 32 && Size != 64)
return false;
unsigned Opcode = IsSgpr ? AMDGPU::S_MOV_B32 : AMDGPU::V_MOV_B32_e32;
if (Size == 32) {
I.setDesc(TII.get(Opcode));
I.addImplicitDefUseOperands(*MF);
return constrainSelectedInstRegOperands(I, TII, TRI, RBI);
}
DebugLoc DL = I.getDebugLoc();
const TargetRegisterClass *RC = IsSgpr ? &AMDGPU::SReg_32_XM0RegClass :
&AMDGPU::VGPR_32RegClass;
unsigned LoReg = MRI.createVirtualRegister(RC);
unsigned HiReg = MRI.createVirtualRegister(RC);
const APInt &Imm = APInt(Size, I.getOperand(1).getImm());
BuildMI(*BB, &I, DL, TII.get(Opcode), LoReg)
.addImm(Imm.trunc(32).getZExtValue());
BuildMI(*BB, &I, DL, TII.get(Opcode), HiReg)
.addImm(Imm.ashr(32).getZExtValue());
const MachineInstr *RS =
BuildMI(*BB, &I, DL, TII.get(AMDGPU::REG_SEQUENCE), DstReg)
.addReg(LoReg)
.addImm(AMDGPU::sub0)
.addReg(HiReg)
.addImm(AMDGPU::sub1);
// We can't call constrainSelectedInstRegOperands here, because it doesn't
// work for target independent opcodes
I.eraseFromParent();
const TargetRegisterClass *DstRC =
TRI.getConstrainedRegClassForOperand(RS->getOperand(0), MRI);
if (!DstRC)
return true;
return RBI.constrainGenericRegister(DstReg, *DstRC, MRI);
}
static bool isConstant(const MachineInstr &MI) {
return MI.getOpcode() == TargetOpcode::G_CONSTANT;
}
void AMDGPUInstructionSelector::getAddrModeInfo(const MachineInstr &Load,
const MachineRegisterInfo &MRI, SmallVectorImpl<GEPInfo> &AddrInfo) const {
const MachineInstr *PtrMI = MRI.getUniqueVRegDef(Load.getOperand(1).getReg());
assert(PtrMI);
if (PtrMI->getOpcode() != TargetOpcode::G_GEP)
return;
GEPInfo GEPInfo(*PtrMI);
for (unsigned i = 1, e = 3; i < e; ++i) {
const MachineOperand &GEPOp = PtrMI->getOperand(i);
const MachineInstr *OpDef = MRI.getUniqueVRegDef(GEPOp.getReg());
assert(OpDef);
if (isConstant(*OpDef)) {
// FIXME: Is it possible to have multiple Imm parts? Maybe if we
// are lacking other optimizations.
assert(GEPInfo.Imm == 0);
GEPInfo.Imm = OpDef->getOperand(1).getCImm()->getSExtValue();
continue;
}
const RegisterBank *OpBank = RBI.getRegBank(GEPOp.getReg(), MRI, TRI);
if (OpBank->getID() == AMDGPU::SGPRRegBankID)
GEPInfo.SgprParts.push_back(GEPOp.getReg());
else
GEPInfo.VgprParts.push_back(GEPOp.getReg());
}
AddrInfo.push_back(GEPInfo);
getAddrModeInfo(*PtrMI, MRI, AddrInfo);
}
bool AMDGPUInstructionSelector::isInstrUniform(const MachineInstr &MI) const {
if (!MI.hasOneMemOperand())
return false;
const MachineMemOperand *MMO = *MI.memoperands_begin();
const Value *Ptr = MMO->getValue();
// UndefValue means this is a load of a kernel input. These are uniform.
// Sometimes LDS instructions have constant pointers.
// If Ptr is null, then that means this mem operand contains a
// PseudoSourceValue like GOT.
if (!Ptr || isa<UndefValue>(Ptr) || isa<Argument>(Ptr) ||
isa<Constant>(Ptr) || isa<GlobalValue>(Ptr))
return true;
if (MMO->getAddrSpace() == AMDGPUAS::CONSTANT_ADDRESS_32BIT)
return true;
const Instruction *I = dyn_cast<Instruction>(Ptr);
return I && I->getMetadata("amdgpu.uniform");
}
bool AMDGPUInstructionSelector::hasVgprParts(ArrayRef<GEPInfo> AddrInfo) const {
for (const GEPInfo &GEPInfo : AddrInfo) {
if (!GEPInfo.VgprParts.empty())
return true;
}
return false;
}
bool AMDGPUInstructionSelector::selectG_LOAD(MachineInstr &I) const {
MachineBasicBlock *BB = I.getParent();
MachineFunction *MF = BB->getParent();
MachineRegisterInfo &MRI = MF->getRegInfo();
DebugLoc DL = I.getDebugLoc();
unsigned DstReg = I.getOperand(0).getReg();
unsigned PtrReg = I.getOperand(1).getReg();
unsigned LoadSize = RBI.getSizeInBits(DstReg, MRI, TRI);
unsigned Opcode;
SmallVector<GEPInfo, 4> AddrInfo;
getAddrModeInfo(I, MRI, AddrInfo);
switch (LoadSize) {
default:
llvm_unreachable("Load size not supported\n");
case 32:
Opcode = AMDGPU::FLAT_LOAD_DWORD;
break;
case 64:
Opcode = AMDGPU::FLAT_LOAD_DWORDX2;
break;
}
MachineInstr *Flat = BuildMI(*BB, &I, DL, TII.get(Opcode))
.add(I.getOperand(0))
.addReg(PtrReg)
.addImm(0) // offset
.addImm(0) // glc
.addImm(0) // slc
.addImm(0); // dlc
bool Ret = constrainSelectedInstRegOperands(*Flat, TII, TRI, RBI);
I.eraseFromParent();
return Ret;
}
bool AMDGPUInstructionSelector::select(MachineInstr &I,
CodeGenCoverage &CoverageInfo) const {
if (!isPreISelGenericOpcode(I.getOpcode())) {
if (I.isCopy())
return selectCOPY(I);
return true;
}
switch (I.getOpcode()) {
default:
return selectImpl(I, CoverageInfo);
case TargetOpcode::G_ADD:
return selectG_ADD(I);
case TargetOpcode::G_INTTOPTR:
case TargetOpcode::G_BITCAST:
return selectCOPY(I);
case TargetOpcode::G_CONSTANT:
case TargetOpcode::G_FCONSTANT:
return selectG_CONSTANT(I);
case TargetOpcode::G_EXTRACT:
return selectG_EXTRACT(I);
case TargetOpcode::G_GEP:
return selectG_GEP(I);
case TargetOpcode::G_IMPLICIT_DEF:
return selectG_IMPLICIT_DEF(I);
case TargetOpcode::G_INSERT:
return selectG_INSERT(I);
case TargetOpcode::G_INTRINSIC:
return selectG_INTRINSIC(I, CoverageInfo);
case TargetOpcode::G_INTRINSIC_W_SIDE_EFFECTS:
return selectG_INTRINSIC_W_SIDE_EFFECTS(I, CoverageInfo);
case TargetOpcode::G_ICMP:
return selectG_ICMP(I);
case TargetOpcode::G_LOAD:
if (selectImpl(I, CoverageInfo))
return true;
return selectG_LOAD(I);
case TargetOpcode::G_SELECT:
return selectG_SELECT(I);
case TargetOpcode::G_STORE:
return selectG_STORE(I);
case TargetOpcode::G_TRUNC:
return selectG_TRUNC(I);
case TargetOpcode::G_SEXT:
case TargetOpcode::G_ZEXT:
case TargetOpcode::G_ANYEXT:
if (selectG_SZA_EXT(I)) {
I.eraseFromParent();
return true;
}
return false;
}
return false;
}
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectVCSRC(MachineOperand &Root) const {
return {{
[=](MachineInstrBuilder &MIB) { MIB.add(Root); }
}};
}
///
/// This will select either an SGPR or VGPR operand and will save us from
/// having to write an extra tablegen pattern.
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectVSRC0(MachineOperand &Root) const {
return {{
[=](MachineInstrBuilder &MIB) { MIB.add(Root); }
}};
}
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectVOP3Mods0(MachineOperand &Root) const {
return {{
[=](MachineInstrBuilder &MIB) { MIB.add(Root); },
[=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // src0_mods
[=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // clamp
[=](MachineInstrBuilder &MIB) { MIB.addImm(0); } // omod
}};
}
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectVOP3OMods(MachineOperand &Root) const {
return {{
[=](MachineInstrBuilder &MIB) { MIB.add(Root); },
[=](MachineInstrBuilder &MIB) { MIB.addImm(0); }, // clamp
[=](MachineInstrBuilder &MIB) { MIB.addImm(0); } // omod
}};
}
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectVOP3Mods(MachineOperand &Root) const {
return {{
[=](MachineInstrBuilder &MIB) { MIB.add(Root); },
[=](MachineInstrBuilder &MIB) { MIB.addImm(0); } // src_mods
}};
}
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectSmrdImm(MachineOperand &Root) const {
MachineRegisterInfo &MRI =
Root.getParent()->getParent()->getParent()->getRegInfo();
SmallVector<GEPInfo, 4> AddrInfo;
getAddrModeInfo(*Root.getParent(), MRI, AddrInfo);
if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
return None;
const GEPInfo &GEPInfo = AddrInfo[0];
if (!AMDGPU::isLegalSMRDImmOffset(STI, GEPInfo.Imm))
return None;
unsigned PtrReg = GEPInfo.SgprParts[0];
int64_t EncodedImm = AMDGPU::getSMRDEncodedOffset(STI, GEPInfo.Imm);
return {{
[=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
[=](MachineInstrBuilder &MIB) { MIB.addImm(EncodedImm); }
}};
}
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectSmrdImm32(MachineOperand &Root) const {
MachineRegisterInfo &MRI =
Root.getParent()->getParent()->getParent()->getRegInfo();
SmallVector<GEPInfo, 4> AddrInfo;
getAddrModeInfo(*Root.getParent(), MRI, AddrInfo);
if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
return None;
const GEPInfo &GEPInfo = AddrInfo[0];
unsigned PtrReg = GEPInfo.SgprParts[0];
int64_t EncodedImm = AMDGPU::getSMRDEncodedOffset(STI, GEPInfo.Imm);
if (!isUInt<32>(EncodedImm))
return None;
return {{
[=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
[=](MachineInstrBuilder &MIB) { MIB.addImm(EncodedImm); }
}};
}
InstructionSelector::ComplexRendererFns
AMDGPUInstructionSelector::selectSmrdSgpr(MachineOperand &Root) const {
MachineInstr *MI = Root.getParent();
MachineBasicBlock *MBB = MI->getParent();
MachineRegisterInfo &MRI = MBB->getParent()->getRegInfo();
SmallVector<GEPInfo, 4> AddrInfo;
getAddrModeInfo(*MI, MRI, AddrInfo);
// FIXME: We should shrink the GEP if the offset is known to be <= 32-bits,
// then we can select all ptr + 32-bit offsets not just immediate offsets.
if (AddrInfo.empty() || AddrInfo[0].SgprParts.size() != 1)
return None;
const GEPInfo &GEPInfo = AddrInfo[0];
if (!GEPInfo.Imm || !isUInt<32>(GEPInfo.Imm))
return None;
// If we make it this far we have a load with an 32-bit immediate offset.
// It is OK to select this using a sgpr offset, because we have already
// failed trying to select this load into one of the _IMM variants since
// the _IMM Patterns are considered before the _SGPR patterns.
unsigned PtrReg = GEPInfo.SgprParts[0];
unsigned OffsetReg = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass);
BuildMI(*MBB, MI, MI->getDebugLoc(), TII.get(AMDGPU::S_MOV_B32), OffsetReg)
.addImm(GEPInfo.Imm);
return {{
[=](MachineInstrBuilder &MIB) { MIB.addReg(PtrReg); },
[=](MachineInstrBuilder &MIB) { MIB.addReg(OffsetReg); }
}};
}
Reference in New Issue View Git Blame Copy Permalink