Re: [patch 00/2] improve .text size on gcc 4.0 and newer compilers

From: Jakub Jelinek
Date: Mon Jan 02 2006 - 16:32:08 EST


On Mon, Jan 02, 2006 at 11:41:24AM -0800, Linus Torvalds wrote:
> > Where does this certainity come from? gcc-3.x (as well as 2.x) each had
> > its own heuristics which functions should be inlined and which should not.
> > inline keyword has always been a hint.
>
> NO IT HAS NOT.
>
> This is total revisionist history by gcc people. It did not use to be a
> hint. If you asked for inlining, you got it unless there was some
> technical reason why gcc couldn't inline it (ie recursive inlining, and
> trampolines and some other issues). End of story.

One of the "technical reasons" was if the function was bigger than some
threshold. And in that case I think it is ok to speak about inline keyword
as a hint. The default inline limit (in rtx count after constant folding,
but not other optimizations) was bigger than in the GCC 3.x era, sure, but
there was a limit and GCC wasn't inlining functions bigger than that limit,
even if they could be simplified due to constant arguments to something
much smaller.

Jakub
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