maxjhandsome
/
llvm-project
forked from OSchip/llvm-project
1
0
Fork 0
Code Issues Pull Requests Packages Releases Wiki Activity

AMDGPU/SI: Add support for spiling SGPRs to scratch buffer 

Summary:
This is necessary for when we run out of VGPRs and can no
longer use v_{read,write}_lane for spilling SGPRs.

Reviewers: arsenm

Subscribers: arsenm, llvm-commits

Differential Revision: http://reviews.llvm.org/D17592

llvm-svn: 262732
This commit is contained in:
Tom Stellard 2016-03-04 18:31:18 +00:00
parent 3b8f6126ac
commit 649b5db557
6 changed files with 134 additions and 29 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

2
llvm/lib/Target/AMDGPU/SIInstrInfo.cpp
View File

@ -590,6 +590,7 @@ void SIInstrInfo::storeRegToStackSlot(MachineBasicBlock &MBB,
.addFrameIndex(FrameIndex) // frame_idx
.addReg(MFI->getScratchRSrcReg()) // scratch_rsrc
.addReg(MFI->getScratchWaveOffsetReg()) // scratch_offset
.addImm(0) // offset
.addMemOperand(MMO);
}
@ -672,6 +673,7 @@ void SIInstrInfo::loadRegFromStackSlot(MachineBasicBlock &MBB,
.addFrameIndex(FrameIndex) // frame_idx
.addReg(MFI->getScratchRSrcReg()) // scratch_rsrc
.addReg(MFI->getScratchWaveOffsetReg()) // scratch_offset
.addImm(0) // offset
.addMemOperand(MMO);
}

5
llvm/lib/Target/AMDGPU/SIInstructions.td
View File

@ -2029,7 +2029,7 @@ multiclass SI_SPILL_VGPR <RegisterClass vgpr_class> {
def _SAVE : InstSI <
(outs),
(ins vgpr_class:$src, i32imm:$frame_idx, SReg_128:$scratch_rsrc,
SReg_32:$scratch_offset),
SReg_32:$scratch_offset, i32imm:$offset),
"", []> {
let mayStore = 1;
let mayLoad = 0;
@ -2037,7 +2037,8 @@ multiclass SI_SPILL_VGPR <RegisterClass vgpr_class> {
def _RESTORE : InstSI <
(outs vgpr_class:$dst),
(ins i32imm:$frame_idx, SReg_128:$scratch_rsrc, SReg_32:$scratch_offset),
(ins i32imm:$frame_idx, SReg_128:$scratch_rsrc, SReg_32:$scratch_offset,
i32imm:$offset),
"", []> {
let mayStore = 0;
let mayLoad = 1;

15
llvm/lib/Target/AMDGPU/SIMachineFunctionInfo.cpp
View File

@ -162,7 +162,7 @@ SIMachineFunctionInfo::SpilledReg SIMachineFunctionInfo::getSpilledReg(
MachineFunction *MF,
unsigned FrameIndex,
unsigned SubIdx) {
const MachineFrameInfo *FrameInfo = MF->getFrameInfo();
MachineFrameInfo *FrameInfo = MF->getFrameInfo();
const SIRegisterInfo *TRI = static_cast<const SIRegisterInfo *>(
MF->getSubtarget<AMDGPUSubtarget>().getRegisterInfo());
MachineRegisterInfo &MRI = MF->getRegInfo();
@ -173,19 +173,15 @@ SIMachineFunctionInfo::SpilledReg SIMachineFunctionInfo::getSpilledReg(
unsigned Lane = (Offset / 4) % 64;
struct SpilledReg Spill;
Spill.Lane = Lane;
if (!LaneVGPRs.count(LaneVGPRIdx)) {
unsigned LaneVGPR = TRI->findUnusedRegister(MRI, &AMDGPU::VGPR_32RegClass);
if (LaneVGPR == AMDGPU::NoRegister) {
LLVMContext &Ctx = MF->getFunction()->getContext();
Ctx.emitError("Ran out of VGPRs for spilling SGPR");
if (LaneVGPR == AMDGPU::NoRegister)
// We have no VGPRs left for spilling SGPRs.
return Spill;
// When compiling from inside Mesa, the compilation continues.
// Select an arbitrary register to avoid triggering assertions
// during subsequent passes.
LaneVGPR = AMDGPU::VGPR0;
}
LaneVGPRs[LaneVGPRIdx] = LaneVGPR;
@ -198,7 +194,6 @@ SIMachineFunctionInfo::SpilledReg SIMachineFunctionInfo::getSpilledReg(
}
Spill.VGPR = LaneVGPRs[LaneVGPRIdx];
Spill.Lane = Lane;
return Spill;
}

3
llvm/lib/Target/AMDGPU/SIMachineFunctionInfo.h
View File

@ -113,8 +113,9 @@ public:
unsigned VGPR;
int Lane;
SpilledReg(unsigned R, int L) : VGPR (R), Lane (L) { }
SpilledReg() : VGPR(0), Lane(-1) { }
SpilledReg() : VGPR(AMDGPU::NoRegister), Lane(-1) { }
bool hasLane() { return Lane != -1;}
bool hasReg() { return VGPR != AMDGPU::NoRegister;}
};
// SIMachineFunctionInfo definition

84
llvm/lib/Target/AMDGPU/SIRegisterInfo.cpp
View File

@ -307,6 +307,7 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
case AMDGPU::SI_SPILL_S64_SAVE:
case AMDGPU::SI_SPILL_S32_SAVE: {
unsigned NumSubRegs = getNumSubRegsForSpillOp(MI->getOpcode());
unsigned TmpReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
for (unsigned i = 0, e = NumSubRegs; i < e; ++i) {
unsigned SubReg = getPhysRegSubReg(MI->getOperand(0).getReg(),
@ -314,15 +315,37 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
struct SIMachineFunctionInfo::SpilledReg Spill =
MFI->getSpilledReg(MF, Index, i);
BuildMI(*MBB, MI, DL,
TII->getMCOpcodeFromPseudo(AMDGPU::V_WRITELANE_B32),
Spill.VGPR)
.addReg(SubReg)
.addImm(Spill.Lane);
if (Spill.hasReg()) {
BuildMI(*MBB, MI, DL,
TII->getMCOpcodeFromPseudo(AMDGPU::V_WRITELANE_B32),
Spill.VGPR)
.addReg(SubReg)
.addImm(Spill.Lane);
// FIXME: Since this spills to another register instead of an actual
// frame index, we should delete the frame index when all references to
// it are fixed.
// FIXME: Since this spills to another register instead of an actual
// frame index, we should delete the frame index when all references to
// it are fixed.
} else {
// Spill SGPR to a frame index.
// FIXME we should use S_STORE_DWORD here for VI.
BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_MOV_B32_e32), TmpReg)
.addReg(SubReg);
unsigned Size = FrameInfo->getObjectSize(Index);
unsigned Align = FrameInfo->getObjectAlignment(Index);
MachinePointerInfo PtrInfo
= MachinePointerInfo::getFixedStack(*MF, Index);
MachineMemOperand *MMO
= MF->getMachineMemOperand(PtrInfo, MachineMemOperand::MOStore,
Size, Align);
BuildMI(*MBB, MI, DL, TII->get(AMDGPU::SI_SPILL_V32_SAVE))
.addReg(TmpReg) // src
.addFrameIndex(Index) // frame_idx
.addReg(MFI->getScratchRSrcReg()) // scratch_rsrc
.addReg(MFI->getScratchWaveOffsetReg()) // scratch_offset
.addImm(i * 4) // offset
.addMemOperand(MMO);
}
}
MI->eraseFromParent();
break;
@ -335,6 +358,7 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
case AMDGPU::SI_SPILL_S64_RESTORE:
case AMDGPU::SI_SPILL_S32_RESTORE: {
unsigned NumSubRegs = getNumSubRegsForSpillOp(MI->getOpcode());
unsigned TmpReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass);
for (unsigned i = 0, e = NumSubRegs; i < e; ++i) {
unsigned SubReg = getPhysRegSubReg(MI->getOperand(0).getReg(),
@ -342,12 +366,38 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
struct SIMachineFunctionInfo::SpilledReg Spill =
MFI->getSpilledReg(MF, Index, i);
BuildMI(*MBB, MI, DL,
TII->getMCOpcodeFromPseudo(AMDGPU::V_READLANE_B32),
SubReg)
.addReg(Spill.VGPR)
.addImm(Spill.Lane)
.addReg(MI->getOperand(0).getReg(), RegState::ImplicitDefine);
if (Spill.hasReg()) {
BuildMI(*MBB, MI, DL,
TII->getMCOpcodeFromPseudo(AMDGPU::V_READLANE_B32),
SubReg)
.addReg(Spill.VGPR)
.addImm(Spill.Lane)
.addReg(MI->getOperand(0).getReg(), RegState::ImplicitDefine);
} else {
// Restore SGPR from a stack slot.
// FIXME: We should use S_LOAD_DWORD here for VI.
unsigned Align = FrameInfo->getObjectAlignment(Index);
unsigned Size = FrameInfo->getObjectSize(Index);
MachinePointerInfo PtrInfo
= MachinePointerInfo::getFixedStack(*MF, Index);
MachineMemOperand *MMO = MF->getMachineMemOperand(
PtrInfo, MachineMemOperand::MOLoad, Size, Align);
BuildMI(*MBB, MI, DL, TII->get(AMDGPU::SI_SPILL_V32_RESTORE), TmpReg)
.addFrameIndex(Index) // frame_idx
.addReg(MFI->getScratchRSrcReg()) // scratch_rsrc
.addReg(MFI->getScratchWaveOffsetReg()) // scratch_offset
.addImm(i * 4) // offset
.addMemOperand(MMO);
BuildMI(*MBB, MI, DL,
TII->getMCOpcodeFromPseudo(AMDGPU::V_READLANE_B32), SubReg)
.addReg(TmpReg)
.addImm(0)
.addReg(MI->getOperand(0).getReg(), RegState::ImplicitDefine);
}
}
// TODO: only do this when it is needed
@ -381,7 +431,8 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
TII->getNamedOperand(*MI, AMDGPU::OpName::src)->getReg(),
TII->getNamedOperand(*MI, AMDGPU::OpName::scratch_rsrc)->getReg(),
TII->getNamedOperand(*MI, AMDGPU::OpName::scratch_offset)->getReg(),
FrameInfo->getObjectOffset(Index));
FrameInfo->getObjectOffset(Index) +
TII->getNamedOperand(*MI, AMDGPU::OpName::offset)->getImm());
MI->eraseFromParent();
break;
case AMDGPU::SI_SPILL_V32_RESTORE:
@ -394,7 +445,8 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
TII->getNamedOperand(*MI, AMDGPU::OpName::dst)->getReg(),
TII->getNamedOperand(*MI, AMDGPU::OpName::scratch_rsrc)->getReg(),
TII->getNamedOperand(*MI, AMDGPU::OpName::scratch_offset)->getReg(),
FrameInfo->getObjectOffset(Index));
FrameInfo->getObjectOffset(Index) +
TII->getNamedOperand(*MI, AMDGPU::OpName::offset)->getImm());
MI->eraseFromParent();
break;
}

54
llvm/test/CodeGen/AMDGPU/si-spill-sgpr-stack.ll Normal file
View File

@ -0,0 +1,54 @@
; RUN: llc -march=amdgcn -mcpu=fiji < %s | FileCheck %s
; Make sure this doesn't crash.
; CHECK: {{^}}test:
; CHECK: s_endpgm
define void @test(i32 addrspace(1)* %out, i32 %in) {
call void asm sideeffect "", "~{SGPR0_SGPR1_SGPR2_SGPR3_SGPR4_SGPR5_SGPR6_SGPR7}" ()
call void asm sideeffect "", "~{SGPR8_SGPR9_SGPR10_SGPR11_SGPR12_SGPR13_SGPR14_SGPR15}" ()
call void asm sideeffect "", "~{SGPR16_SGPR17_SGPR18_SGPR19_SGPR20_SGPR21_SGPR22_SGPR23}" ()
call void asm sideeffect "", "~{SGPR24_SGPR25_SGPR26_SGPR27_SGPR28_SGPR29_SGPR30_SGPR31}" ()
call void asm sideeffect "", "~{SGPR32_SGPR33_SGPR34_SGPR35_SGPR36_SGPR37_SGPR38_SGPR39}" ()
call void asm sideeffect "", "~{SGPR40_SGPR41_SGPR42_SGPR43_SGPR44_SGPR45_SGPR46_SGPR47}" ()
call void asm sideeffect "", "~{SGPR48_SGPR49_SGPR50_SGPR51_SGPR52_SGPR53_SGPR54_SGPR55}" ()
call void asm sideeffect "", "~{SGPR56_SGPR57_SGPR58_SGPR59_SGPR60_SGPR61_SGPR62_SGPR63}" ()
call void asm sideeffect "", "~{SGPR64_SGPR65_SGPR66_SGPR67_SGPR68_SGPR69_SGPR70_SGPR71}" ()
call void asm sideeffect "", "~{SGPR72_SGPR73_SGPR74_SGPR75_SGPR76_SGPR77_SGPR78_SGPR79}" ()
call void asm sideeffect "", "~{SGPR80_SGPR81_SGPR82_SGPR83_SGPR84_SGPR85_SGPR86_SGPR87}" ()
call void asm sideeffect "", "~{SGPR88_SGPR89_SGPR90_SGPR91_SGPR92_SGPR93_SGPR94_SGPR95}" ()
call void asm sideeffect "", "~{VGPR0_VGPR1_VGPR2_VGPR3_VGPR4_VGPR5_VGPR6_VGPR7}" ()
call void asm sideeffect "", "~{VGPR8_VGPR9_VGPR10_VGPR11_VGPR12_VGPR13_VGPR14_VGPR15}" ()
call void asm sideeffect "", "~{VGPR16_VGPR17_VGPR18_VGPR19_VGPR20_VGPR21_VGPR22_VGPR23}" ()
call void asm sideeffect "", "~{VGPR24_VGPR25_VGPR26_VGPR27_VGPR28_VGPR29_VGPR30_VGPR31}" ()
call void asm sideeffect "", "~{VGPR32_VGPR33_VGPR34_VGPR35_VGPR36_VGPR37_VGPR38_VGPR39}" ()
call void asm sideeffect "", "~{VGPR40_VGPR41_VGPR42_VGPR43_VGPR44_VGPR45_VGPR46_VGPR47}" ()
call void asm sideeffect "", "~{VGPR48_VGPR49_VGPR50_VGPR51_VGPR52_VGPR53_VGPR54_VGPR55}" ()
call void asm sideeffect "", "~{VGPR56_VGPR57_VGPR58_VGPR59_VGPR60_VGPR61_VGPR62_VGPR63}" ()
call void asm sideeffect "", "~{VGPR64_VGPR65_VGPR66_VGPR67_VGPR68_VGPR69_VGPR70_VGPR71}" ()
call void asm sideeffect "", "~{VGPR72_VGPR73_VGPR74_VGPR75_VGPR76_VGPR77_VGPR78_VGPR79}" ()
call void asm sideeffect "", "~{VGPR80_VGPR81_VGPR82_VGPR83_VGPR84_VGPR85_VGPR86_VGPR87}" ()
call void asm sideeffect "", "~{VGPR88_VGPR89_VGPR90_VGPR91_VGPR92_VGPR93_VGPR94_VGPR95}" ()
call void asm sideeffect "", "~{VGPR96_VGPR97_VGPR98_VGPR99_VGPR100_VGPR101_VGPR102_VGPR103}" ()
call void asm sideeffect "", "~{VGPR104_VGPR105_VGPR106_VGPR107_VGPR108_VGPR109_VGPR110_VGPR111}" ()
call void asm sideeffect "", "~{VGPR112_VGPR113_VGPR114_VGPR115_VGPR116_VGPR117_VGPR118_VGPR119}" ()
call void asm sideeffect "", "~{VGPR120_VGPR121_VGPR122_VGPR123_VGPR124_VGPR125_VGPR126_VGPR127}" ()
call void asm sideeffect "", "~{VGPR128_VGPR129_VGPR130_VGPR131_VGPR132_VGPR133_VGPR134_VGPR135}" ()
call void asm sideeffect "", "~{VGPR136_VGPR137_VGPR138_VGPR139_VGPR140_VGPR141_VGPR142_VGPR143}" ()
call void asm sideeffect "", "~{VGPR144_VGPR145_VGPR146_VGPR147_VGPR148_VGPR149_VGPR150_VGPR151}" ()
call void asm sideeffect "", "~{VGPR152_VGPR153_VGPR154_VGPR155_VGPR156_VGPR157_VGPR158_VGPR159}" ()
call void asm sideeffect "", "~{VGPR160_VGPR161_VGPR162_VGPR163_VGPR164_VGPR165_VGPR166_VGPR167}" ()
call void asm sideeffect "", "~{VGPR168_VGPR169_VGPR170_VGPR171_VGPR172_VGPR173_VGPR174_VGPR175}" ()
call void asm sideeffect "", "~{VGPR176_VGPR177_VGPR178_VGPR179_VGPR180_VGPR181_VGPR182_VGPR183}" ()
call void asm sideeffect "", "~{VGPR184_VGPR185_VGPR186_VGPR187_VGPR188_VGPR189_VGPR190_VGPR191}" ()
call void asm sideeffect "", "~{VGPR192_VGPR193_VGPR194_VGPR195_VGPR196_VGPR197_VGPR198_VGPR199}" ()
call void asm sideeffect "", "~{VGPR200_VGPR201_VGPR202_VGPR203_VGPR204_VGPR205_VGPR206_VGPR207}" ()
call void asm sideeffect "", "~{VGPR208_VGPR209_VGPR210_VGPR211_VGPR212_VGPR213_VGPR214_VGPR215}" ()
call void asm sideeffect "", "~{VGPR216_VGPR217_VGPR218_VGPR219_VGPR220_VGPR221_VGPR222_VGPR223}" ()
call void asm sideeffect "", "~{VGPR224_VGPR225_VGPR226_VGPR227_VGPR228_VGPR229_VGPR230_VGPR231}" ()
call void asm sideeffect "", "~{VGPR232_VGPR233_VGPR234_VGPR235_VGPR236_VGPR237_VGPR238_VGPR239}" ()
call void asm sideeffect "", "~{VGPR240_VGPR241_VGPR242_VGPR243_VGPR244_VGPR245_VGPR246_VGPR247}" ()
call void asm sideeffect "", "~{VGPR248_VGPR249_VGPR250_VGPR251_VGPR252_VGPR253_VGPR254_VGPR255}" ()
store i32 %in, i32 addrspace(1)* %out
ret void
}