Re: Performance problem: unaligned loads/stores on structure assignments on MIPS

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Performance problem: unaligned loads/stores on ...
\ Simon Kagstrom (25 Feb 2007)
. \ Ian Lance Taylor (27 Feb 2007)

Subject:	Re: Performance problem: unaligned loads/stores on structure assignments on MIPS
Group:	Gcc-help
From:	Ian Lance Taylor
Date:	27 Feb 2007

Simon Kagstrom <simon.kagstrom> writes:

> GCC 4.1 seems to sometimes generate inefficient code when doing
> structure assignments directly when compiling for MIPS1. When assigning
> to structure members manually, it generates regular lw/sw sequences.
> When assigning to the structure, you instead get lwl/lwr and swl/swr
> pairs (for no reason, since the data is aligned).

...

> Should I consider this a bug and report it to the bug tracking system?
> I looked for similar problems, but couldn't find any matching bug report.

This seems like a bug to me.

Ian