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Optimizations for the MIPS target
- From: Nikolaos Kavvadias <nkavv at physics dot auth dot gr>
- To: gcc at gcc dot gnu dot org
- Date: Thu, 04 May 2006 16:31:15 +0300
- Subject: Optimizations for the MIPS target
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Hi there
i have a few questions on the optimizations for the MIPS target,
mostly regarding load/store instructions.
1. In the code generated for global symbols (e.g. arrays), the
alignment is always at 4-byte boundary and not at 1-byte boundary
(.align 0).
E.g.:
.align 2
some_array:
.byte some_integer
...
My question here is: culdn't "-Os" optimization option force .align 0
alignment? Is there any way to use the minimal data memory
requirements for global symbols possible?
2. The MIPS backend prefers to emit the lw,sw instructions for -O3.
lb,lbu etc.. are only used by the -Os option.
However, i'm not sure that there is a clear code size advantage for
using these variants. What I mean is: shouldn't they be used always?
thanks in advance
Nikolaos Kavvadias
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