[PATCH] D67502: [InstSimplify] simplifyUnsignedRangeCheck(): '(a+b) </>= c &&/|| (a+b) ==/!= 0' if we known 'c' is 'a' or 'b' and is non-zero (PR43259)

Thu Sep 12 10:11:09 PDT 2019

lebedev.ri planned changes to this revision.
lebedev.ri marked 4 inline comments as done.
lebedev.ri added inline comments.

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Comment at: llvm/test/Transforms/InstSimplify/result-of-add-of-negative-is-non-zero-and-no-underflow.ll:91-92
+
+; We need to know that the value we compare with here (%base) is non-zero,
+; so knowledge about %offset won't do.
+define i1 @t5_bad(i8 %base, i8 %offset) {
----------------
spatel wrote:
> I thought you proved this test already?
> https://rise4fun.com/Alive/WslQ
Uhm.
Looks like i'm losing the plot because all these patterns in these patches are so similar.
I should wait until three existing patches lang, and then deal with PR43259

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  rG LLVM Github Monorepo

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https://reviews.llvm.org/D67502