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-rw-r--r--contrib/llvm/lib/Target/R600/SIRegisterInfo.cpp74
1 files changed, 60 insertions, 14 deletions
diff --git a/contrib/llvm/lib/Target/R600/SIRegisterInfo.cpp b/contrib/llvm/lib/Target/R600/SIRegisterInfo.cpp
index 58c2cd109680..f50299112604 100644
--- a/contrib/llvm/lib/Target/R600/SIRegisterInfo.cpp
+++ b/contrib/llvm/lib/Target/R600/SIRegisterInfo.cpp
@@ -14,7 +14,6 @@
#include "SIRegisterInfo.h"
-#include "AMDGPUSubtarget.h"
#include "SIInstrInfo.h"
#include "SIMachineFunctionInfo.h"
#include "llvm/CodeGen/MachineFrameInfo.h"
@@ -47,13 +46,31 @@ BitVector SIRegisterInfo::getReservedRegs(const MachineFunction &MF) const {
Reserved.set(AMDGPU::VGPR255);
Reserved.set(AMDGPU::VGPR254);
+ // Tonga and Iceland can only allocate a fixed number of SGPRs due
+ // to a hw bug.
+ if (ST.hasSGPRInitBug()) {
+ unsigned NumSGPRs = AMDGPU::SGPR_32RegClass.getNumRegs();
+ // Reserve some SGPRs for FLAT_SCRATCH and VCC (4 SGPRs).
+ // Assume XNACK_MASK is unused.
+ unsigned Limit = AMDGPUSubtarget::FIXED_SGPR_COUNT_FOR_INIT_BUG - 4;
+
+ for (unsigned i = Limit; i < NumSGPRs; ++i) {
+ unsigned Reg = AMDGPU::SGPR_32RegClass.getRegister(i);
+ MCRegAliasIterator R = MCRegAliasIterator(Reg, this, true);
+
+ for (; R.isValid(); ++R)
+ Reserved.set(*R);
+ }
+ }
+
return Reserved;
}
unsigned SIRegisterInfo::getRegPressureSetLimit(unsigned Idx) const {
// FIXME: We should adjust the max number of waves based on LDS size.
- unsigned SGPRLimit = getNumSGPRsAllowed(ST.getMaxWavesPerCU());
+ unsigned SGPRLimit = getNumSGPRsAllowed(ST.getGeneration(),
+ ST.getMaxWavesPerCU());
unsigned VGPRLimit = getNumVGPRsAllowed(ST.getMaxWavesPerCU());
for (regclass_iterator I = regclass_begin(), E = regclass_end();
@@ -204,7 +221,9 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
Ctx.emitError("Ran out of VGPRs for spilling SGPR");
}
- BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_WRITELANE_B32), Spill.VGPR)
+ BuildMI(*MBB, MI, DL,
+ TII->getMCOpcodeFromPseudo(AMDGPU::V_WRITELANE_B32),
+ Spill.VGPR)
.addReg(SubReg)
.addImm(Spill.Lane);
@@ -236,7 +255,9 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
if (isM0)
SubReg = RS->scavengeRegister(&AMDGPU::SGPR_32RegClass, MI, 0);
- BuildMI(*MBB, MI, DL, TII->get(AMDGPU::V_READLANE_B32), SubReg)
+ BuildMI(*MBB, MI, DL,
+ TII->getMCOpcodeFromPseudo(AMDGPU::V_READLANE_B32),
+ SubReg)
.addReg(Spill.VGPR)
.addImm(Spill.Lane)
.addReg(MI->getOperand(0).getReg(), RegState::ImplicitDefine);
@@ -245,7 +266,22 @@ void SIRegisterInfo::eliminateFrameIndex(MachineBasicBlock::iterator MI,
.addReg(SubReg);
}
}
- TII->insertNOPs(MI, 3);
+
+ // TODO: only do this when it is needed
+ switch (ST.getGeneration()) {
+ case AMDGPUSubtarget::SOUTHERN_ISLANDS:
+ // "VALU writes SGPR" -> "SMRD reads that SGPR" needs "S_NOP 3" on SI
+ TII->insertNOPs(MI, 3);
+ break;
+ case AMDGPUSubtarget::SEA_ISLANDS:
+ break;
+ default: // VOLCANIC_ISLANDS and later
+ // "VALU writes SGPR -> VMEM reads that SGPR" needs "S_NOP 4" on VI
+ // and later. This also applies to VALUs which write VCC, but we're
+ // unlikely to see VMEM use VCC.
+ TII->insertNOPs(MI, 4);
+ }
+
MI->eraseFromParent();
break;
}
@@ -490,14 +526,24 @@ unsigned SIRegisterInfo::getNumVGPRsAllowed(unsigned WaveCount) const {
}
}
-unsigned SIRegisterInfo::getNumSGPRsAllowed(unsigned WaveCount) const {
- switch(WaveCount) {
- case 10: return 48;
- case 9: return 56;
- case 8: return 64;
- case 7: return 72;
- case 6: return 80;
- case 5: return 96;
- default: return 103;
+unsigned SIRegisterInfo::getNumSGPRsAllowed(AMDGPUSubtarget::Generation gen,
+ unsigned WaveCount) const {
+ if (gen >= AMDGPUSubtarget::VOLCANIC_ISLANDS) {
+ switch (WaveCount) {
+ case 10: return 80;
+ case 9: return 80;
+ case 8: return 96;
+ default: return 102;
+ }
+ } else {
+ switch(WaveCount) {
+ case 10: return 48;
+ case 9: return 56;
+ case 8: return 64;
+ case 7: return 72;
+ case 6: return 80;
+ case 5: return 96;
+ default: return 103;
+ }
}
}