//===----------------------------------------------------------------------===//
#include "AMDGPU.h"
+#include "AMDGPUSubtarget.h"
#include "SIInstrInfo.h"
#include "SIMachineFunctionInfo.h"
+#include "llvm/CodeGen/MachineFrameInfo.h"
#include "llvm/CodeGen/MachineFunction.h"
#include "llvm/CodeGen/MachineFunctionPass.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
void Kill(MachineInstr &MI);
void Branch(MachineInstr &MI);
- void InitM0ForLDS(MachineBasicBlock::iterator MI);
void LoadM0(MachineInstr &MI, MachineInstr *MovRel);
void IndirectSrc(MachineInstr &MI);
void IndirectDst(MachineInstr &MI);
MachineBasicBlock &MBB = *MI.getParent();
DebugLoc DL = MI.getDebugLoc();
- if (MBB.getParent()->getInfo<SIMachineFunctionInfo>()->ShaderType !=
+ if (MBB.getParent()->getInfo<SIMachineFunctionInfo>()->getShaderType() !=
ShaderType::PIXEL ||
!shouldSkip(&MBB, &MBB.getParent()->back()))
return;
DebugLoc DL = MI.getDebugLoc();
const MachineOperand &Op = MI.getOperand(0);
- // Kill is only allowed in pixel / geometry shaders
- assert(MBB.getParent()->getInfo<SIMachineFunctionInfo>()->ShaderType ==
- ShaderType::PIXEL ||
- MBB.getParent()->getInfo<SIMachineFunctionInfo>()->ShaderType ==
- ShaderType::GEOMETRY);
+#ifndef NDEBUG
+ const SIMachineFunctionInfo *MFI
+ = MBB.getParent()->getInfo<SIMachineFunctionInfo>();
+ // Kill is only allowed in pixel / geometry shaders.
+ assert(MFI->getShaderType() == ShaderType::PIXEL ||
+ MFI->getShaderType() == ShaderType::GEOMETRY);
+#endif
// Clear this thread from the exec mask if the operand is negative
- if ((Op.isImm() || Op.isFPImm())) {
+ if ((Op.isImm())) {
// Constant operand: Set exec mask to 0 or do nothing
- if (Op.isImm() ? (Op.getImm() & 0x80000000) :
- Op.getFPImm()->isNegative()) {
+ if (Op.getImm() & 0x80000000) {
BuildMI(MBB, &MI, DL, TII->get(AMDGPU::S_MOV_B64), AMDGPU::EXEC)
.addImm(0);
}
MI.eraseFromParent();
}
-/// The m0 register stores the maximum allowable address for LDS reads and
-/// writes. Its value must be at least the size in bytes of LDS allocated by
-/// the shader. For simplicity, we set it to the maximum possible value.
-void SILowerControlFlowPass::InitM0ForLDS(MachineBasicBlock::iterator MI) {
- BuildMI(*MI->getParent(), MI, MI->getDebugLoc(), TII->get(AMDGPU::S_MOV_B32),
- AMDGPU::M0).addImm(0xffffffff);
-}
-
void SILowerControlFlowPass::LoadM0(MachineInstr &MI, MachineInstr *MovRel) {
MachineBasicBlock &MBB = *MI.getParent();
} else {
assert(AMDGPU::SReg_64RegClass.contains(Save));
- assert(AMDGPU::VReg_32RegClass.contains(Idx));
+ assert(AMDGPU::VGPR_32RegClass.contains(Idx));
// Save the EXEC mask
BuildMI(MBB, &MI, DL, TII->get(AMDGPU::S_MOV_B64), Save)
.addReg(Save);
}
- // FIXME: Are there any values other than the LDS address clamp that need to
- // be stored in the m0 register and may be live for more than a few
- // instructions? If so, we should save the m0 register at the beginning
- // of this function and restore it here.
- // FIXME: Add support for LDS direct loads.
- InitM0ForLDS(&MI);
MI.eraseFromParent();
}
}
bool SILowerControlFlowPass::runOnMachineFunction(MachineFunction &MF) {
- TII = static_cast<const SIInstrInfo*>(MF.getTarget().getInstrInfo());
- TRI = static_cast<const SIRegisterInfo*>(MF.getTarget().getRegisterInfo());
+ TII = static_cast<const SIInstrInfo *>(MF.getSubtarget().getInstrInfo());
+ TRI =
+ static_cast<const SIRegisterInfo *>(MF.getSubtarget().getRegisterInfo());
SIMachineFunctionInfo *MFI = MF.getInfo<SIMachineFunctionInfo>();
bool HaveKill = false;
- bool NeedM0 = false;
bool NeedWQM = false;
+ bool NeedFlat = false;
unsigned Depth = 0;
for (MachineFunction::iterator BI = MF.begin(), BE = MF.end();
Next = std::next(I);
MachineInstr &MI = *I;
- if (TII->isDS(MI.getOpcode())) {
- NeedM0 = true;
+ if (TII->isWQM(MI.getOpcode()) || TII->isDS(MI.getOpcode()))
NeedWQM = true;
- }
+
+ // Flat uses m0 in case it needs to access LDS.
+ if (TII->isFLAT(MI.getOpcode()))
+ NeedFlat = true;
switch (MI.getOpcode()) {
default: break;
case AMDGPU::SI_INDIRECT_DST_V16:
IndirectDst(MI);
break;
-
- case AMDGPU::V_INTERP_P1_F32:
- case AMDGPU::V_INTERP_P2_F32:
- case AMDGPU::V_INTERP_MOV_F32:
- NeedWQM = true;
- break;
-
}
}
}
- if (NeedM0) {
+ if (NeedWQM && MFI->getShaderType() == ShaderType::PIXEL) {
MachineBasicBlock &MBB = MF.front();
- // Initialize M0 to a value that won't cause LDS access to be discarded
- // due to offset clamping
- InitM0ForLDS(MBB.getFirstNonPHI());
+ BuildMI(MBB, MBB.getFirstNonPHI(), DebugLoc(), TII->get(AMDGPU::S_WQM_B64),
+ AMDGPU::EXEC).addReg(AMDGPU::EXEC);
}
- if (NeedWQM && MFI->ShaderType == ShaderType::PIXEL) {
+ // FIXME: This seems inappropriate to do here.
+ if (NeedFlat && MFI->IsKernel) {
+ // Insert the prologue initializing the SGPRs pointing to the scratch space
+ // for flat accesses.
+ const MachineFrameInfo *FrameInfo = MF.getFrameInfo();
+
+ // TODO: What to use with function calls?
+
+ // FIXME: This is reporting stack size that is used in a scratch buffer
+ // rather than registers as well.
+ uint64_t StackSizeBytes = FrameInfo->getStackSize();
+
+ int IndirectBegin
+ = static_cast<const AMDGPUInstrInfo*>(TII)->getIndirectIndexBegin(MF);
+ // Convert register index to 256-byte unit.
+ uint64_t StackOffset = IndirectBegin < 0 ? 0 : (4 * IndirectBegin / 256);
+
+ assert((StackSizeBytes < 0xffff) && StackOffset < 0xffff &&
+ "Stack limits should be smaller than 16-bits");
+
+ // Initialize the flat scratch register pair.
+ // TODO: Can we use one s_mov_b64 here?
+
+ // Offset is in units of 256-bytes.
MachineBasicBlock &MBB = MF.front();
- BuildMI(MBB, MBB.getFirstNonPHI(), DebugLoc(), TII->get(AMDGPU::S_WQM_B64),
- AMDGPU::EXEC).addReg(AMDGPU::EXEC);
+ DebugLoc NoDL;
+ MachineBasicBlock::iterator Start = MBB.getFirstNonPHI();
+ const MCInstrDesc &SMovK = TII->get(AMDGPU::S_MOVK_I32);
+
+ assert(isInt<16>(StackOffset) && isInt<16>(StackSizeBytes));
+
+ BuildMI(MBB, Start, NoDL, SMovK, AMDGPU::FLAT_SCR_LO)
+ .addImm(StackOffset);
+
+ // Documentation says size is "per-thread scratch size in bytes"
+ BuildMI(MBB, Start, NoDL, SMovK, AMDGPU::FLAT_SCR_HI)
+ .addImm(StackSizeBytes);
}
return true;