* [PATCH, rs6000] Remove DImode from SLOW_UNALIGNED_ACCESS
@ 2012-04-17 14:56 Pat Haugen
2012-04-17 15:09 ` David Edelsohn
0 siblings, 1 reply; 2+ messages in thread
From: Pat Haugen @ 2012-04-17 14:56 UTC (permalink / raw)
To: gcc-patches; +Cc: David Edelsohn
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DImode references do not suffer a major performance hit for < 4-byte aligned access like the float types.
Bootstrap/regtest on powerpc64-linux with no new regressions. Ok for trunk?
-Pat
2012-04-17 Pat Haugen <pthaugen@us.ibm.com>
* config/rs6000/rs6000.h (SLOW_UNALIGNED_ACCESS): Remove DImode.
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Index: gcc/config/rs6000/rs6000.h
===================================================================
--- gcc/config/rs6000/rs6000.h (revision 186389)
+++ gcc/config/rs6000/rs6000.h (working copy)
@@ -771,8 +771,7 @@ extern unsigned rs6000_pointer_size;
#define SLOW_UNALIGNED_ACCESS(MODE, ALIGN) \
(STRICT_ALIGNMENT \
|| (((MODE) == SFmode || (MODE) == DFmode || (MODE) == TFmode \
- || (MODE) == SDmode || (MODE) == DDmode || (MODE) == TDmode \
- || (MODE) == DImode) \
+ || (MODE) == SDmode || (MODE) == DDmode || (MODE) == TDmode) \
&& (ALIGN) < 32) \
|| (VECTOR_MODE_P ((MODE)) && (((int)(ALIGN)) < VECTOR_ALIGN (MODE))))
^ permalink raw reply [flat|nested] 2+ messages in thread
* Re: [PATCH, rs6000] Remove DImode from SLOW_UNALIGNED_ACCESS
2012-04-17 14:56 [PATCH, rs6000] Remove DImode from SLOW_UNALIGNED_ACCESS Pat Haugen
@ 2012-04-17 15:09 ` David Edelsohn
0 siblings, 0 replies; 2+ messages in thread
From: David Edelsohn @ 2012-04-17 15:09 UTC (permalink / raw)
To: Pat Haugen; +Cc: gcc-patches
On Tue, Apr 17, 2012 at 10:55 AM, Pat Haugen
<pthaugen@linux.vnet.ibm.com> wrote:
> DImode references do not suffer a major performance hit for < 4-byte aligned
> access like the float types.
>
> Bootstrap/regtest on powerpc64-linux with no new regressions. Ok for trunk?
>
> 2012-04-17 Pat Haugen <pthaugen@us.ibm.com>
>
> * config/rs6000/rs6000.h (SLOW_UNALIGNED_ACCESS): Remove DImode.
Okay.
I think this may have been introduced at the time the port was 32 bit
and DImode values sometimes were allocated to FPRs.
Thanks, David
^ permalink raw reply [flat|nested] 2+ messages in thread
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