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Sanjay Patel
1e95676e58
http://rise4fun.com/Alive/i8Q A narrow bitwise logic op is obviously better than math for value tracking, and zext is better than sext. Typically, the 'not' will be folded into an icmp predicate. The IR difference would even survive through codegen for x86, so we would see worse code: https://godbolt.org/g/C14HMF one_or_zero(int, int): # @one_or_zero(int, int) xorl %eax, %eax cmpl %esi, %edi setle %al retq one_or_zero_alt(int, int): # @one_or_zero_alt(int, int) xorl %ecx, %ecx cmpl %esi, %edi setg %cl movl $1, %eax subl %ecx, %eax retq git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@306243 91177308-0d34-0410-b5e6-96231b3b80d8
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