Fix build warning caused by mixed signed/unsigned compare #69797
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added 3 commits
October 20, 2023 12:33
In SimplifyIndvar::replaceFloatIVWithIntegerIV() the return value of getFPMantissaWidth() was being cast as an unsigned integer and then compared with the number of bits needed to represent an integer that was cast to and from a floating-point type. This is a problem because getFPMantissaWidth() returns -1 if the type does not have a stable mantissa. Currently the only type that returns -1 is ppc_fp128, so you'd need a pretty big induction variable to cause a problem. However, this problem will be more likely to be exposed when we implement support for decimal floating-point types. Strictly speaking, what we want to know here is the size of the biggest integer that can be represented exactly. We could get that information even with an unstable mantissa width, but getFPMantissaWidth() won't do it.
This fixes a build warning caused by mixed signed/unsigned compare
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Oct 26, 2023
Local branch amd-gfx cda2378 Merged main:28ae42e66251 into amd-gfx:b6fe60a67eed Remote branch main 4e0c6d3 Fix build warning caused by mixed signed/unsigned compare (llvm#69797)
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