diff options
Diffstat (limited to 'contrib/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp')
| -rw-r--r-- | contrib/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp | 14 |
1 files changed, 11 insertions, 3 deletions
diff --git a/contrib/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp b/contrib/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp index 02a3930..6230d1e 100644 --- a/contrib/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp +++ b/contrib/llvm/lib/Target/AMDGPU/SIFoldOperands.cpp @@ -334,12 +334,20 @@ bool SIFoldOperands::runOnMachineFunction(MachineFunction &MF) { !MRI.hasOneUse(MI.getOperand(0).getReg())) continue; - // FIXME: Fold operands with subregs. if (OpToFold.isReg() && - (!TargetRegisterInfo::isVirtualRegister(OpToFold.getReg()) || - OpToFold.getSubReg())) + !TargetRegisterInfo::isVirtualRegister(OpToFold.getReg())) continue; + // Prevent folding operands backwards in the function. For example, + // the COPY opcode must not be replaced by 1 in this example: + // + // %vreg3<def> = COPY %VGPR0; VGPR_32:%vreg3 + // ... + // %VGPR0<def> = V_MOV_B32_e32 1, %EXEC<imp-use> + MachineOperand &Dst = MI.getOperand(0); + if (Dst.isReg() && + !TargetRegisterInfo::isVirtualRegister(Dst.getReg())) + continue; // We need mutate the operands of new mov instructions to add implicit // uses of EXEC, but adding them invalidates the use_iterator, so defer |
