llvm-project/llvm/lib/Target/NVPTX/NVPTXInstrInfo.cpp

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9.2 KiB
C++

//===- NVPTXInstrInfo.cpp - NVPTX 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 NVPTX implementation of the TargetInstrInfo class.
//
//===----------------------------------------------------------------------===//
#include "NVPTX.h"
#include "NVPTXInstrInfo.h"
#include "NVPTXTargetMachine.h"
#include "llvm/ADT/STLExtras.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
#include "llvm/IR/Function.h"
using namespace llvm;
#define GET_INSTRINFO_CTOR_DTOR
#include "NVPTXGenInstrInfo.inc"
// Pin the vtable to this file.
void NVPTXInstrInfo::anchor() {}
// FIXME: Add the subtarget support on this constructor.
NVPTXInstrInfo::NVPTXInstrInfo(NVPTXSubtarget &STI)
: NVPTXGenInstrInfo(), RegInfo(STI) {}
void NVPTXInstrInfo::copyPhysReg(
MachineBasicBlock &MBB, MachineBasicBlock::iterator I, DebugLoc DL,
unsigned DestReg, unsigned SrcReg, bool KillSrc) const {
const MachineRegisterInfo &MRI = MBB.getParent()->getRegInfo();
const TargetRegisterClass *DestRC = MRI.getRegClass(DestReg);
const TargetRegisterClass *SrcRC = MRI.getRegClass(SrcReg);
if (DestRC != SrcRC)
report_fatal_error("Attempted to created cross-class register copy");
if (DestRC == &NVPTX::Int32RegsRegClass)
BuildMI(MBB, I, DL, get(NVPTX::IMOV32rr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (DestRC == &NVPTX::Int1RegsRegClass)
BuildMI(MBB, I, DL, get(NVPTX::IMOV1rr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (DestRC == &NVPTX::Float32RegsRegClass)
BuildMI(MBB, I, DL, get(NVPTX::FMOV32rr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (DestRC == &NVPTX::Int16RegsRegClass)
BuildMI(MBB, I, DL, get(NVPTX::IMOV16rr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (DestRC == &NVPTX::Int64RegsRegClass)
BuildMI(MBB, I, DL, get(NVPTX::IMOV64rr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else if (DestRC == &NVPTX::Float64RegsRegClass)
BuildMI(MBB, I, DL, get(NVPTX::FMOV64rr), DestReg)
.addReg(SrcReg, getKillRegState(KillSrc));
else {
llvm_unreachable("Bad register copy");
}
}
bool NVPTXInstrInfo::isMoveInstr(const MachineInstr &MI, unsigned &SrcReg,
unsigned &DestReg) const {
// Look for the appropriate part of TSFlags
bool isMove = false;
unsigned TSFlags =
(MI.getDesc().TSFlags & NVPTX::SimpleMoveMask) >> NVPTX::SimpleMoveShift;
isMove = (TSFlags == 1);
if (isMove) {
MachineOperand dest = MI.getOperand(0);
MachineOperand src = MI.getOperand(1);
assert(dest.isReg() && "dest of a movrr is not a reg");
assert(src.isReg() && "src of a movrr is not a reg");
SrcReg = src.getReg();
DestReg = dest.getReg();
return true;
}
return false;
}
bool NVPTXInstrInfo::isReadSpecialReg(MachineInstr &MI) const {
switch (MI.getOpcode()) {
default:
return false;
case NVPTX::INT_PTX_SREG_NTID_X:
case NVPTX::INT_PTX_SREG_NTID_Y:
case NVPTX::INT_PTX_SREG_NTID_Z:
case NVPTX::INT_PTX_SREG_TID_X:
case NVPTX::INT_PTX_SREG_TID_Y:
case NVPTX::INT_PTX_SREG_TID_Z:
case NVPTX::INT_PTX_SREG_CTAID_X:
case NVPTX::INT_PTX_SREG_CTAID_Y:
case NVPTX::INT_PTX_SREG_CTAID_Z:
case NVPTX::INT_PTX_SREG_NCTAID_X:
case NVPTX::INT_PTX_SREG_NCTAID_Y:
case NVPTX::INT_PTX_SREG_NCTAID_Z:
case NVPTX::INT_PTX_SREG_WARPSIZE:
return true;
}
}
bool NVPTXInstrInfo::isLoadInstr(const MachineInstr &MI,
unsigned &AddrSpace) const {
bool isLoad = false;
unsigned TSFlags =
(MI.getDesc().TSFlags & NVPTX::isLoadMask) >> NVPTX::isLoadShift;
isLoad = (TSFlags == 1);
if (isLoad)
AddrSpace = getLdStCodeAddrSpace(MI);
return isLoad;
}
bool NVPTXInstrInfo::isStoreInstr(const MachineInstr &MI,
unsigned &AddrSpace) const {
bool isStore = false;
unsigned TSFlags =
(MI.getDesc().TSFlags & NVPTX::isStoreMask) >> NVPTX::isStoreShift;
isStore = (TSFlags == 1);
if (isStore)
AddrSpace = getLdStCodeAddrSpace(MI);
return isStore;
}
bool NVPTXInstrInfo::CanTailMerge(const MachineInstr *MI) const {
unsigned addrspace = 0;
if (MI->getOpcode() == NVPTX::INT_CUDA_SYNCTHREADS)
return false;
if (isLoadInstr(*MI, addrspace))
if (addrspace == NVPTX::PTXLdStInstCode::SHARED)
return false;
if (isStoreInstr(*MI, addrspace))
if (addrspace == NVPTX::PTXLdStInstCode::SHARED)
return false;
return true;
}
/// AnalyzeBranch - Analyze the branching code at the end of MBB, returning
/// true if it cannot be understood (e.g. it's a switch dispatch or isn't
/// implemented for a target). Upon success, this returns false and returns
/// with the following information in various cases:
///
/// 1. If this block ends with no branches (it just falls through to its succ)
/// just return false, leaving TBB/FBB null.
/// 2. If this block ends with only an unconditional branch, it sets TBB to be
/// the destination block.
/// 3. If this block ends with an conditional branch and it falls through to
/// an successor block, it sets TBB to be the branch destination block and a
/// list of operands that evaluate the condition. These
/// operands can be passed to other TargetInstrInfo methods to create new
/// branches.
/// 4. If this block ends with an conditional branch and an unconditional
/// block, it returns the 'true' destination in TBB, the 'false' destination
/// in FBB, and a list of operands that evaluate the condition. These
/// operands can be passed to other TargetInstrInfo methods to create new
/// branches.
///
/// Note that RemoveBranch and InsertBranch must be implemented to support
/// cases where this method returns success.
///
bool NVPTXInstrInfo::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 (LastInst->getOpcode() == NVPTX::GOTO) {
TBB = LastInst->getOperand(0).getMBB();
return false;
} else if (LastInst->getOpcode() == NVPTX::CBranch) {
// Block ends with fall-through condbranch.
TBB = LastInst->getOperand(1).getMBB();
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 NVPTX::GOTO and NVPTX:CBranch, handle it.
if (SecondLastInst->getOpcode() == NVPTX::CBranch &&
LastInst->getOpcode() == NVPTX::GOTO) {
TBB = SecondLastInst->getOperand(1).getMBB();
Cond.push_back(SecondLastInst->getOperand(0));
FBB = LastInst->getOperand(0).getMBB();
return false;
}
// If the block ends with two NVPTX:GOTOs, handle it. The second one is not
// executed, so remove it.
if (SecondLastInst->getOpcode() == NVPTX::GOTO &&
LastInst->getOpcode() == NVPTX::GOTO) {
TBB = SecondLastInst->getOperand(0).getMBB();
I = LastInst;
if (AllowModify)
I->eraseFromParent();
return false;
}
// Otherwise, can't handle this.
return true;
}
unsigned NVPTXInstrInfo::RemoveBranch(MachineBasicBlock &MBB) const {
MachineBasicBlock::iterator I = MBB.end();
if (I == MBB.begin())
return 0;
--I;
if (I->getOpcode() != NVPTX::GOTO && I->getOpcode() != NVPTX::CBranch)
return 0;
// Remove the branch.
I->eraseFromParent();
I = MBB.end();
if (I == MBB.begin())
return 1;
--I;
if (I->getOpcode() != NVPTX::CBranch)
return 1;
// Remove the branch.
I->eraseFromParent();
return 2;
}
unsigned NVPTXInstrInfo::InsertBranch(
MachineBasicBlock &MBB, MachineBasicBlock *TBB, MachineBasicBlock *FBB,
const SmallVectorImpl<MachineOperand> &Cond, DebugLoc DL) const {
// Shouldn't be a fall through.
assert(TBB && "InsertBranch must not be told to insert a fallthrough");
assert((Cond.size() == 1 || Cond.size() == 0) &&
"NVPTX branch conditions have two components!");
// One-way branch.
if (!FBB) {
if (Cond.empty()) // Unconditional branch
BuildMI(&MBB, DL, get(NVPTX::GOTO)).addMBB(TBB);
else // Conditional branch
BuildMI(&MBB, DL, get(NVPTX::CBranch)).addReg(Cond[0].getReg())
.addMBB(TBB);
return 1;
}
// Two-way Conditional Branch.
BuildMI(&MBB, DL, get(NVPTX::CBranch)).addReg(Cond[0].getReg()).addMBB(TBB);
BuildMI(&MBB, DL, get(NVPTX::GOTO)).addMBB(FBB);
return 2;
}