[LLVMdev] Inline Asm Question

[Chris Lattner]

On Sat, 6 Jan 2007, Bill Wendling wrote:
> I couldn't find any documentation on this, but was wondering if
> people here knew what this inline asm means:
>         __asm__ ("{cntlz|cntlzw} %0,%1"
>                 : "=r" (__ctz_c)
>                 : "r" (__ctz_x & -__ctz_x));
>
> I'm assuming that "{cntlz|cntlzw}" indicates that one or the other of
> these asm mnemonics are used. But how does this get decided?

The first is AT&T syntax, the second is intel syntax.  The GCC 
documentation is the canonical place to find out stuff like this, we 
adhere to their syntax.

-Chris

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