[PATCH] D86878: [AMDGPU] Fix a miscompile with S_ADD/S_SUB

[Piotr Sobczak via Phabricator via llvm-commits]

piotr added inline comments.


================
Comment at: llvm/lib/Target/AMDGPU/AMDGPUISelDAGToDAG.cpp:1056
+    unsigned CondOpc = CI->getOpcode();
+    if (CondOpc == ISD::AND || CondOpc == ISD::OR || CondOpc == ISD::XOR) {
+      auto ST = static_cast<const GCNSubtarget *>(Subtarget);
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arsenm wrote:
> I don't think it will end up mattering with the operations legal for i1 (although maybe trunc is also a problem), but I think it would be somewhat safer to list valid boolean sources instead
Will do, but what do you mean exactly by "valid boolean sources" here?


================
Comment at: llvm/test/CodeGen/AMDGPU/combine-add-zext-xor.ll:16
+
+define void @combine_add_zext_xor() {
+.entry:
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arsenm wrote:
> Should be able to reduce this more
This already comes from bugpoint, but I will try to reduce the test a bit more.


Repository:
  rG LLVM Github Monorepo

CHANGES SINCE LAST ACTION
  https://reviews.llvm.org/D86878/new/

https://reviews.llvm.org/D86878