diff options
| -rw-r--r-- | llvm/lib/CodeGen/RegisterCoalescer.cpp | 1 | ||||
| -rw-r--r-- | llvm/test/CodeGen/AMDGPU/subreg-coalescer-undef-use.ll | 20 |
2 files changed, 21 insertions, 0 deletions
diff --git a/llvm/lib/CodeGen/RegisterCoalescer.cpp b/llvm/lib/CodeGen/RegisterCoalescer.cpp index 7b7c7502172..7afea2a4f6f 100644 --- a/llvm/lib/CodeGen/RegisterCoalescer.cpp +++ b/llvm/lib/CodeGen/RegisterCoalescer.cpp @@ -1449,6 +1449,7 @@ bool RegisterCoalescer::joinCopy(MachineInstr *CopyMI, bool &Again) { << format("%04X", S.LaneMask) << ")\n"); LIS->shrinkToUses(S, LI.reg); } + LI.removeEmptySubRanges(); } if (ShrinkMainRange) { LiveInterval &LI = LIS->getInterval(CP.getDstReg()); diff --git a/llvm/test/CodeGen/AMDGPU/subreg-coalescer-undef-use.ll b/llvm/test/CodeGen/AMDGPU/subreg-coalescer-undef-use.ll new file mode 100644 index 00000000000..e023a622984 --- /dev/null +++ b/llvm/test/CodeGen/AMDGPU/subreg-coalescer-undef-use.ll @@ -0,0 +1,20 @@ +; RUN: llc -march=amdgcn -mcpu=SI -o /dev/null %s +; Don't crash when the use of an undefined value is only detected by the +; register coalescer because it is hidden with subregister insert/extract. +target triple="amdgcn--" + +define void @foobar(float %a0, float %a1, float addrspace(1)* %out) nounwind { +entry: + %v0 = insertelement <4 x float> undef, float %a0, i32 0 + br i1 undef, label %ift, label %ife + +ift: + %v1 = insertelement <4 x float> undef, float %a1, i32 0 + br label %ife + +ife: + %val = phi <4 x float> [ %v1, %ift ], [ %v0, %entry ] + %v2 = extractelement <4 x float> %val, i32 1 + store float %v2, float addrspace(1)* %out, align 4 + ret void +} |
