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Re: gcc4.5 ivopts question.
kumon@aa.mbn.or.jp writes:
> When a C source program uses pointer auto increment operator within a
> loop, sometimes ivopts replaces a pointer reference to an indexed memory access,
> which causes poor performance in my case. The detail description
> attached bellow. Does somebody give me a suggestion?
The usual way to address this kind of thing is to adjust the
TARGET_RTX_COSTS hook to return appropriate costs for pointer
addressing vs. indexed memory addressing.
If you compile with -fdump-tree-ivopts-details you will get a dump
file which should give you some information about the costs that the
ivopts pass is using.
Ian