[M3commit] CVS Update: cm3
jkrell at elego.de
Tue Oct 1 08:22:21 CEST 2013
Changes by: jkrell at birch. 13/10/01 08:22:21
only avoid the gcc type limit warning when using gcc < 4.3
that is, generate operations like ==, <, >, >=, <=, != inline
instead of via function calls.
The only reason for the function calls is to evade
gcc looking for a reason to warn, like when saying
unsigned i < 0 (might be good to optimize
these away in the frontend, but I'm not holding my breath;
might also be good for C backend to optimize them away,
but I'm still not holding my breath -- I did try to
address this and there are significant remnants in the
code, but it was proving more difficult than I expected;
essentially every expression carried whether or not it
had a min or max and what they were -- though the real
generality is a set of ranges the expression might fall within;
and then optimize comparisons that can be proven from those
I've only actually tested this change with gcc < 4.3.
I still need to test with gcc >= 4.3 or non-gcc.
In particular, I was stepping into these functions on AMD64_NT.
When using later versions of gcc, user must pass -Wno-type-limits
or somesuch, if he passes -Wall -Wextra or somesuch.
Previously the warnings were never generated by any version
of gcc, but at great inefficiency, and annoyint debugging.
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