http://gcc.gnu.org/bugzilla/show_bug.cgi?id=29963
--- Comment #3 from Oleg Endo <olegendo at gcc dot gnu.org> 2012-11-13 00:53:45
UTC ---
(In reply to comment #2)
> But it is not uncommon to load the program into RAM before executing,
> e.g. because the ROM it's stored in is too slow.
Newer SH2A devices with on-chip flash have some facilities to fix that ;)
>
> In that case, you could indeed only do this optimization for constant
> variables / arrays.
>
True. For example in such cases as:
const char* test (void)
{
return "test";
}
.file "sh_tmp.cpp"
.text
.little
.section .rodata.str1.4,"aMS",@progbits,1
.align 2
.LC0:
.string "test"
.text
.align 1
.global __Z4testv
.type __Z4testv, @function
__Z4testv:
mov.l .L2,r0
rts
nop
.L3:
.align 2
.L2:
.long .LC0
.size __Z4testv, .-__Z4testv
.ident "GCC: (GNU) 4.8.0 20121112 (experimental)"
The string constant could be placed in .text instead of .rodata, even without
link time relaxation:
__Z4testv:
mova .L2,r0
rts
nop
.L3:
.align 2
.L2:
.string "test"
However, it might have negative effects on the overall constant pool usage. I
guess there should be a limit on the size (and the number of) elements that are
moved from .rodata to .text.
