llvm-project/llvm/lib/Target/Mips/MipsLegalizerInfo.cpp

102 lines
3.1 KiB
C++

//===- MipsLegalizerInfo.cpp ------------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
/// \file
/// This file implements the targeting of the Machinelegalizer class for Mips.
/// \todo This should be generated by TableGen.
//===----------------------------------------------------------------------===//
#include "MipsLegalizerInfo.h"
#include "MipsTargetMachine.h"
#include "llvm/CodeGen/GlobalISel/LegalizerHelper.h"
using namespace llvm;
MipsLegalizerInfo::MipsLegalizerInfo(const MipsSubtarget &ST) {
using namespace TargetOpcode;
const LLT s32 = LLT::scalar(32);
const LLT s64 = LLT::scalar(64);
const LLT p0 = LLT::pointer(0, 32);
getActionDefinitionsBuilder(G_ADD)
.legalFor({s32})
.minScalar(0, s32)
.customFor({s64});
getActionDefinitionsBuilder({G_LOAD, G_STORE})
.legalForCartesianProduct({p0, s32}, {p0});
getActionDefinitionsBuilder({G_AND, G_OR, G_XOR, G_SHL, G_ASHR, G_LSHR})
.legalFor({s32});
getActionDefinitionsBuilder(G_ICMP)
.legalFor({{s32, s32}})
.minScalar(0, s32);
getActionDefinitionsBuilder(G_CONSTANT)
.legalFor({s32})
.clampScalar(0, s32, s32);
getActionDefinitionsBuilder(G_GEP)
.legalFor({{p0, s32}});
getActionDefinitionsBuilder(G_FRAME_INDEX)
.legalFor({p0});
getActionDefinitionsBuilder(G_GLOBAL_VALUE)
.legalFor({p0});
computeTables();
verify(*ST.getInstrInfo());
}
bool MipsLegalizerInfo::legalizeCustom(MachineInstr &MI,
MachineRegisterInfo &MRI,
MachineIRBuilder &MIRBuilder,
GISelChangeObserver &Observer) const {
using namespace TargetOpcode;
MIRBuilder.setInstr(MI);
switch (MI.getOpcode()) {
case G_ADD: {
unsigned Size = MRI.getType(MI.getOperand(0).getReg()).getSizeInBits();
const LLT sHalf = LLT::scalar(Size / 2);
unsigned RHSLow = MRI.createGenericVirtualRegister(sHalf);
unsigned RHSHigh = MRI.createGenericVirtualRegister(sHalf);
unsigned LHSLow = MRI.createGenericVirtualRegister(sHalf);
unsigned LHSHigh = MRI.createGenericVirtualRegister(sHalf);
unsigned ResLow = MRI.createGenericVirtualRegister(sHalf);
unsigned ResHigh = MRI.createGenericVirtualRegister(sHalf);
unsigned Carry = MRI.createGenericVirtualRegister(sHalf);
unsigned TmpResHigh = MRI.createGenericVirtualRegister(sHalf);
MIRBuilder.buildUnmerge({RHSLow, RHSHigh}, MI.getOperand(2).getReg());
MIRBuilder.buildUnmerge({LHSLow, LHSHigh}, MI.getOperand(1).getReg());
MIRBuilder.buildAdd(TmpResHigh, LHSHigh, RHSHigh);
MIRBuilder.buildAdd(ResLow, LHSLow, RHSLow);
MIRBuilder.buildICmp(CmpInst::ICMP_ULT, Carry, ResLow, LHSLow);
MIRBuilder.buildAdd(ResHigh, TmpResHigh, Carry);
MIRBuilder.buildMerge(MI.getOperand(0).getReg(), {ResLow, ResHigh});
MI.eraseFromParent();
break;
}
default:
return false;
}
return true;
}