[PATCH, x86_64]: Provide longlong.h definitions for 128bit operations

Uros Bizjak ubizjak@gmail.com
Thu May 17 05:57:00 GMT 2007


On 5/16/07, Chris Lattner <clattner@apple.com> wrote:

> > This patch adds 128bit operations for x86_64 to longlong.h to speed
> > up TImode and TFmode arithmetic.
>
> Why not implement these in terms of TImode operations themselves?
> Inline asm should be avoided when it can be :)

Unfortunatelly longlong.h definitions require their operands to be in
DImode (for x86_64 target). I guess it is not a coincidence, that
these definitions can be implemented with exactly one x86 insn (two
for carry-propagating addition and subtraction). Asm with one insn is
not harmful.

Uros.



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