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Author ajaksu2
Recipients ajaksu2, alexandre.vassalotti, bboissin, blaisorblade, christian.heimes, djc, lemburg, pitrou, rhettinger, skip.montanaro, theatrus
Date 2009-01-04.03:07:08
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Paolo 'Blaisorblade' Giarrusso  wrote:
> 1st note: is that code from the threaded version? [...] It is vital to
> this patch that the jump is not shared, something similar to
> -fno-crossjumping should be found.

Yes, threaded version by unconditionally defining USE_THREADED_CODE
(old patch version :).

Ok,  I'll try to find a way to get at -fno-crossjumping behavior. BTW,
man gcc suggests using -fno-gcse for programs that use computed gotos
(couldn't fin

>  In the code you posted, one can see that the program
> counter is spilled to memory by GCC, but isn't by ICC. Either the spill
> is elsewhere, or ICC is better here.
I can [mail you|attach here] icc's output if you want to check the
overall code, it's about 1.9M with the code annotations.

> Finally, I'm a bit surprised by "addl $1, %ecx", since any peephole
> optimizer should remove that; I'm not shocked just because I've never
> seen perfect GCC output.

I'm glad to see the same issue in Alexandre's output, not my fault then :D

The command line I used (after a clean build with gcc) was:
icc  -pthread -c -fno-strict-aliasing -DNDEBUG -g -fwrapv -O3 -w  -I.
-IInclude -I./Include   -DPy_BUILD_CORE  -S -fcode-asm -fsource-asm
-dA Python/ceval.c

(same as with gcc, except for warnings and -fcode-asm -fsource-asm).
Date User Action Args
2009-01-04 03:07:10ajaksu2setrecipients: + ajaksu2, lemburg, skip.montanaro, rhettinger, pitrou, christian.heimes, alexandre.vassalotti, djc, bboissin, blaisorblade, theatrus
2009-01-04 03:07:09ajaksu2linkissue4753 messages
2009-01-04 03:07:08ajaksu2create