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Re: Add an "early rematerialisation" pass
On 12/14/2017 12:32 PM, Richard Biener wrote:
>
> On x86_64 all xmm registers are caller saved for example. That means all FP regs and all vectors. (yeah, stupid ABI decision....)
But that's precisely what I would expect if one was looking to maintain
backwards compatibility within the core runtime libraries.
If you make something callee-saved, then you have to have space for it
in the setjmp buffer. Expanding that buffer is an ABI change and thus
*highly* discouraged.
jeff