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Re: Initial shrink-wrapping patch


On 10/06/11 17:57, Ian Lance Taylor wrote:
> There is absolutely no reason to try to shrink wrap that code.  It will
> never help.  That code always has to be first.  It especially has to be
> first because the gold linker recognizes the prologue specially when a
> split-stack function calls a non-split-stack function, in order to
> request a larger stack.

Urgh, ok.

> Therefore, it seems to me that we should apply shrink wrapping to the
> function as it exists *before* the split-stack prologue is created.  The
> flag_split_stack bit should be moved after the flag_shrink_wrap bit.

Sounds like we just need to always emit the split prologue on the
original entry edge then. Can you test the following with Go?


Bernd

Attachment: split-seq.diff
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