Messages in this thread | | | Date | Sun, 14 Jul 2013 19:30:00 +0000 | Subject | Re: [LLVMdev] [PATCH] x86/asm: avoid mnemonics without type suffix | From | Tim Northover <> |
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> And that is why I think you should just consider "bt $x,y" to be > trivially the same thing and not at all ambiguous. Because there is > ABSOLUTELY ZERO ambiguity when people write > > bt $63, mem > > Zero. Nada. None. The semantics are *exactly* the same for btl and btq > in this case, so why would you want the user to specify one or the > other?
I don't think you've actually tested that, have you? (x86-64)
int main() { long val = 0xffffffff; char res;
asm("btl $63, %1\n\tsetc %0" : "=r"(res) : "m"(val)); printf("%d\n", res);
asm("btq $63, %1\n\tsetc %0" : "=r"(res) : "m"(val)); printf("%d\n", res); }
Tim.
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