optimization of volatile functions

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Article #51029

#51029

From: Richard Draves
Date: Tue, 13 Jul 1993 23:44

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I have an important code path which uses functions that don't return.
I'd hoped that by declaring the functions volatile gcc would
optimize away unnecessary register saves & restores. I'd like
to avoid saving callee-saved registers in the prologue of a volatile
function and avoid saving caller-saved registers before a call
to a volatile function. However, a quick test (gcc 2.3.3, mips)
seemed to indicate that gcc doesn't have this optimization.

1) Can gcc perform this optimization for volatile functions?

2) If not, how hard would it be to add this optimization?

Thanks,
Rich

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From: rpd+@cs.cmu.edu (Richard Draves)
Subject: optimization of volatile functions
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Date: Tue, 13 Jul 1993 23:44:20 GMT
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