Richard Sandiford <richard.sandif...@linaro.org> writes:
> Segher Boessenkool <seg...@kernel.crashing.org> writes:
>> Hi!
>>
>> On Fri, Jan 26, 2018 at 01:25:51PM +0000, Richard Sandiford wrote:
>>> if (SCALAR_INT_MODE_P (inmode))
>>> new_out_reg = gen_lowpart_SUBREG (outmode, reg);
>>> else
>>> - new_out_reg = gen_rtx_SUBREG (outmode, reg, 0);
>>> + {
>>> + poly_uint64 offset = subreg_lowpart_offset (outmode, inmode);
>>> + new_out_reg = gen_rtx_SUBREG (outmode, reg, offset);
>>> + }
>>
>> Is this now not exactly the same as the SCALAR_INT_MODE_P case? The mode
>> of "reg" is inmode, after all?
>
> Bah, yes. Don't know how I missed that. :-( I think I must have
> been reading it as SCALAR_INT_P, and thinking this was some weird
> VOIDmode thing.
>
> Will fix.
Like so. Tested as before. OK to install?
Thanks,
Richard
2018-02-02 Richard Sandiford <richard.sandif...@linaro.org>
gcc/
* lra-constraints.c (match_reload): Unconditionally use
gen_lowpart_SUBREG, rather than selecting between that
and equivalent gen_rtx_SUBREG code.
Index: gcc/lra-constraints.c
===================================================================
--- gcc/lra-constraints.c 2018-01-31 14:14:16.701405568 +0000
+++ gcc/lra-constraints.c 2018-02-02 14:14:50.701951577 +0000
@@ -942,13 +942,7 @@ match_reload (signed char out, signed ch
reg = new_in_reg
= lra_create_new_reg_with_unique_value (inmode, in_rtx,
goal_class, "");
- if (SCALAR_INT_MODE_P (inmode))
- new_out_reg = gen_lowpart_SUBREG (outmode, reg);
- else
- {
- poly_uint64 offset = subreg_lowpart_offset (outmode, inmode);
- new_out_reg = gen_rtx_SUBREG (outmode, reg, offset);
- }
+ new_out_reg = gen_lowpart_SUBREG (outmode, reg);
LRA_SUBREG_P (new_out_reg) = 1;
/* If the input reg is dying here, we can use the same hard
register for REG and IN_RTX. We do it only for original
@@ -965,13 +959,7 @@ match_reload (signed char out, signed ch
reg = new_out_reg
= lra_create_new_reg_with_unique_value (outmode, out_rtx,
goal_class, "");
- if (SCALAR_INT_MODE_P (outmode))
- new_in_reg = gen_lowpart_SUBREG (inmode, reg);
- else
- {
- poly_uint64 offset = subreg_lowpart_offset (inmode, outmode);
- new_in_reg = gen_rtx_SUBREG (inmode, reg, offset);
- }
+ new_in_reg = gen_lowpart_SUBREG (inmode, reg);
/* NEW_IN_REG is non-paradoxical subreg. We don't want
NEW_OUT_REG living above. We add clobber clause for
this. This is just a temporary clobber. We can remove
