diff options
Diffstat (limited to 'lib/Target/AMDGPU/SIRegisterInfo.cpp')
-rw-r--r-- | lib/Target/AMDGPU/SIRegisterInfo.cpp | 120 |
1 files changed, 106 insertions, 14 deletions
diff --git a/lib/Target/AMDGPU/SIRegisterInfo.cpp b/lib/Target/AMDGPU/SIRegisterInfo.cpp index 06cfc95be96a..6fb01a09fe13 100644 --- a/lib/Target/AMDGPU/SIRegisterInfo.cpp +++ b/lib/Target/AMDGPU/SIRegisterInfo.cpp @@ -117,11 +117,7 @@ unsigned SIRegisterInfo::reservedPrivateSegmentBufferReg( return getMatchingSuperReg(BaseReg, AMDGPU::sub0, &AMDGPU::SReg_128RegClass); } -unsigned SIRegisterInfo::reservedPrivateSegmentWaveByteOffsetReg( - const MachineFunction &MF) const { - - const SISubtarget &ST = MF.getSubtarget<SISubtarget>(); - unsigned RegCount = ST.getMaxNumSGPRs(MF); +static unsigned findPrivateSegmentWaveByteOffsetRegIndex(unsigned RegCount) { unsigned Reg; // Try to place it in a hole after PrivateSegmentBufferReg. @@ -134,9 +130,22 @@ unsigned SIRegisterInfo::reservedPrivateSegmentWaveByteOffsetReg( // wave offset before it. Reg = RegCount - 5; } + + return Reg; +} + +unsigned SIRegisterInfo::reservedPrivateSegmentWaveByteOffsetReg( + const MachineFunction &MF) const { + const SISubtarget &ST = MF.getSubtarget<SISubtarget>(); + unsigned Reg = findPrivateSegmentWaveByteOffsetRegIndex(ST.getMaxNumSGPRs(MF)); return AMDGPU::SGPR_32RegClass.getRegister(Reg); } +unsigned SIRegisterInfo::reservedStackPtrOffsetReg( + const MachineFunction &MF) const { + return AMDGPU::SGPR32; +} + BitVector SIRegisterInfo::getReservedRegs(const MachineFunction &MF) const { BitVector Reserved(getNumRegs()); Reserved.set(AMDGPU::INDIRECT_BASE_ADDR); @@ -198,15 +207,33 @@ BitVector SIRegisterInfo::getReservedRegs(const MachineFunction &MF) const { assert(!isSubRegister(ScratchRSrcReg, ScratchWaveOffsetReg)); } + unsigned StackPtrReg = MFI->getStackPtrOffsetReg(); + if (StackPtrReg != AMDGPU::NoRegister) { + reserveRegisterTuples(Reserved, StackPtrReg); + assert(!isSubRegister(ScratchRSrcReg, StackPtrReg)); + } + + unsigned FrameReg = MFI->getFrameOffsetReg(); + if (FrameReg != AMDGPU::NoRegister) { + reserveRegisterTuples(Reserved, FrameReg); + assert(!isSubRegister(ScratchRSrcReg, FrameReg)); + } + return Reserved; } bool SIRegisterInfo::requiresRegisterScavenging(const MachineFunction &Fn) const { - return Fn.getFrameInfo().hasStackObjects(); + const SIMachineFunctionInfo *Info = Fn.getInfo<SIMachineFunctionInfo>(); + if (Info->isEntryFunction()) { + const MachineFrameInfo &MFI = Fn.getFrameInfo(); + return MFI.hasStackObjects() || MFI.hasCalls(); + } + + // May need scavenger for dealing with callee saved registers. + return true; } -bool -SIRegisterInfo::requiresFrameIndexScavenging(const MachineFunction &MF) const { +bool SIRegisterInfo::requiresFrameIndexScavenging(const MachineFunction &MF) const { return MF.getFrameInfo().hasStackObjects(); } @@ -318,8 +345,11 @@ void SIRegisterInfo::resolveFrameIndex(MachineInstr &MI, unsigned BaseReg, MachineOperand *FIOp = TII->getNamedOperand(MI, AMDGPU::OpName::vaddr); assert(FIOp && FIOp->isFI() && "frame index must be address operand"); - assert(TII->isMUBUF(MI)); + assert(TII->getNamedOperand(MI, AMDGPU::OpName::soffset)->getReg() == + MF->getInfo<SIMachineFunctionInfo>()->getFrameOffsetReg() && + "should only be seeing frame offset relative FrameIndex"); + MachineOperand *OffsetOp = TII->getNamedOperand(MI, AMDGPU::OpName::offset); int64_t NewOffset = OffsetOp->getImm() + Offset; @@ -981,12 +1011,72 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI, } default: { - if (TII->isMUBUF(*MI)) { + const DebugLoc &DL = MI->getDebugLoc(); + bool IsMUBUF = TII->isMUBUF(*MI); + + if (!IsMUBUF && + MFI->getFrameOffsetReg() != MFI->getScratchWaveOffsetReg()) { + // Convert to an absolute stack address by finding the offset from the + // scratch wave base and scaling by the wave size. + // + // In an entry function/kernel the stack address is already the absolute + // address relative to the the scratch wave offset. + + unsigned DiffReg + = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass); + + bool IsCopy = MI->getOpcode() == AMDGPU::V_MOV_B32_e32; + unsigned ResultReg = IsCopy ? + MI->getOperand(0).getReg() : + MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass); + + BuildMI(*MBB, MI, DL, TII->get(AMDGPU::S_SUB_U32), DiffReg) + .addReg(MFI->getFrameOffsetReg()) + .addReg(MFI->getScratchWaveOffsetReg()); + + int64_t Offset = FrameInfo.getObjectOffset(Index); + if (Offset == 0) { + // XXX - This never happens because of emergency scavenging slot at 0? + BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_LSHRREV_B32_e64), ResultReg) + .addImm(Log2_32(ST.getWavefrontSize())) + .addReg(DiffReg); + } else { + unsigned CarryOut + = MRI.createVirtualRegister(&AMDGPU::SReg_64_XEXECRegClass); + unsigned ScaledReg + = MRI.createVirtualRegister(&AMDGPU::SReg_32_XM0RegClass); + + // XXX - Should this use a vector shift? + BuildMI(*MBB, MI, DL, TII->get(AMDGPU::S_LSHR_B32), ScaledReg) + .addReg(DiffReg, RegState::Kill) + .addImm(Log2_32(ST.getWavefrontSize())); + + // TODO: Fold if use instruction is another add of a constant. + BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_ADD_I32_e64), ResultReg) + .addReg(CarryOut, RegState::Define | RegState::Dead) + .addImm(Offset) + .addReg(ScaledReg, RegState::Kill); + + MRI.setRegAllocationHint(CarryOut, 0, AMDGPU::VCC); + } + + // Don't introduce an extra copy if we're just materializing in a mov. + if (IsCopy) + MI->eraseFromParent(); + else + FIOp.ChangeToRegister(ResultReg, false, false, true); + return; + } + + if (IsMUBUF) { // Disable offen so we don't need a 0 vgpr base. assert(static_cast<int>(FIOperandNum) == AMDGPU::getNamedOperandIdx(MI->getOpcode(), AMDGPU::OpName::vaddr)); + assert(TII->getNamedOperand(*MI, AMDGPU::OpName::soffset)->getReg() + == MFI->getFrameOffsetReg()); + int64_t Offset = FrameInfo.getObjectOffset(Index); int64_t OldImm = TII->getNamedOperand(*MI, AMDGPU::OpName::offset)->getImm(); @@ -995,17 +1085,19 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI, if (isUInt<12>(NewOffset) && buildMUBUFOffsetLoadStore(TII, FrameInfo, MI, Index, NewOffset)) { MI->eraseFromParent(); - break; + return; } } + // If the offset is simply too big, don't convert to a scratch wave offset + // relative index. + int64_t Offset = FrameInfo.getObjectOffset(Index); FIOp.ChangeToImmediate(Offset); if (!TII->isImmOperandLegal(*MI, FIOperandNum, FIOp)) { unsigned TmpReg = MRI.createVirtualRegister(&AMDGPU::VGPR_32RegClass); - BuildMI(*MBB, MI, MI->getDebugLoc(), - TII->get(AMDGPU::V_MOV_B32_e32), TmpReg) - .addImm(Offset); + BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_MOV_B32_e32), TmpReg) + .addImm(Offset); FIOp.ChangeToRegister(TmpReg, false, false, true); } } |