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[Bug middle-end/28690] [4.2 Regression] Performace problem with indexed load/stores on powerpc



------- Comment #21 from bonzini at gnu dot org  2006-10-03 18:07 -------
Note that I don't oppose at all fixing the problem in
swap_commutative_operands_p.  At the very least, you have to change at the very
least simplify-rtx.c's uses of commutative_operand_precedence to use s_c_o_p
instead, but that's a minor problem.

I'm also worried of the interaction between this change to
swap_commutative_operands_p and swap_commutative_operands_with_target which
(even though I refactored it quite recently to happen very early, in expand) is
an optimization that CSE has performed for years and has big impact on x86, for
example on crafty.


-- 


http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28690


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