extend the computeOverflowForSignedSub/computeOverflowForUnsignedSub implementations with ConstantRange, and add tests #67724
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| ; AVX-NEXT: retq | ||
| %x = call { <4 x i8>, <4 x i1> } @llvm.usub.with.overflow.v4i8(<4 x i8> <i8 255, i8 255, i8 255, i8 255>, <4 x i8> <i8 128, i8 0, i8 255, i8 1>) | ||
| ret { <4 x i8>, <4 x i1> } %x | ||
| } |
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Please can you pre-commit these (or would you like me to?) so this patch shows the codegen diff
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OK, I will but can you tell me what are the expectations and how can I see the difference?
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Give me just a small example of what should the code do, so that I will have more understanding of the problem.
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I pulled the tests from InstCombine/with_overfow.ll
but the difference between the two commits is so small, just one or two assembly lines. Is that even possible?
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What we need to do is show the codegen diff from the patch - so ideally this patch needs to be split into a stack of 2 commits - the first just adds the new tests with the current codegen, then the second commit, with the computeOverflowFor*Sub implementations, shows the change in the codegen for the tests.
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I understand that, I mean what do computeOverflowFor*Sub functions do?
What optimizations they perform?
I will split the pull now.
…mplementations with ConstantRange
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I will create a new pull request, I think I messed up everything here. |
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