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[Bug target/34903] -Os code size regression



------- Comment #9 from dje at gcc dot gnu dot org  2008-01-22 15:59 -------
GCC does not use the load and store multiple instructions because the source
file declares r29 a global variable:

register volatile gd_t *gd asm ("r29");

The bug fix mentioned above inhibits GCC from using lmw/stmw if global
registers are present in the contiguous register sequence because GCC
incorrectly would overwrite the register.  If the register variable declaration
is removed, GCC uses the lmw/stmw instructions.  r29 is a bad choice for a
global register variable.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=34903


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