[PowerPC] Use zext instead of anyext in custom and combine #68784
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This custom combine currently converts an `and(anyext(x),c)` into `anyext(and(x,c))`. This is not correct, because the original expression guaranteed that the high bits are zero, while the new one sets them to undef. Emit `zext(and(x,c))` instead. Fixes llvm#68783.
stefanp-ibm
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Oct 11, 2023
nikic
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Oct 13, 2023
This custom combine currently converts `and(anyext(x),c)` into `anyext(and(x,c))`. This is not correct, because the original expression guaranteed that the high bits are zero, while the new one sets them to undef. Emit `zext(and(x,c))` instead. Fixes llvm#68783. (cherry picked from commit 127ed9a)
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This custom combine currently converts
and(anyext(x),c)intoanyext(and(x,c)). This is not correct, because the original expression guaranteed that the high bits are zero, while the new one sets them to undef.Emit
zext(and(x,c))instead.Fixes #68783.