[LLVMdev] Stange behavior in fp arithmetics on x86 (bug possibly) (original) (raw)

Stephen Checkoway s at pahtak.org
Fri Oct 10 07:57:20 PDT 2014

On Oct 10, 2014, at 7:23 AM, Pasi Parviainen <pasi.parviainen at iki.fi> wrote:

On 10.10.2014 9:48, Stephen Checkoway wrote:

But more to the point, even if there's a good reason to accept retl/retq as input, is there any reason to emit it ever? Since in x86 you can mix 16-bit and 32-bit code, therefore you must be able to distinguish between 16-bit and 32-bit return. And from there comes the w and l suffix for the return instruction.

Makes total sense. I didn't think about using the operand size override. (I didn't even realize that was legal for ret.)

Thanks,

-- Stephen Checkoway

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