| Message ID | 53747F0B.2060107@arm.com |
|---|---|
| State | New |
| Headers | show |
On 15/05/14 09:47, Kyrill Tkachov wrote: > Hi all, > > Shifted arithmetic operations can never be encoded in 16-bits in and therefore > can not appear in Thumb2 IT blocks under ARMv8-A rules (and the -mrestrict-it > rules). This patch adjusts the relevant pattern for that purpose. > > Tested and bootstrapped on arm-none-linux-gnueabihf and made sure no performance > regressions on a number of benchmarks. > > This is a bug (not wrong-code though) in -mrestrict-it that affects 4.9 as well > as trunk, so is it ok to backport it there? > > > Thanks, > Kyrill > > 2014-05-15 Kyrylo Tkachov <kyrylo.tkachov@arm.com> > > * config/arm/arm.md (arith_shiftsi): Do not predicate for > arm_restrict_it. > OK both. R.
commit 8d54d43e84925ee5c53e70ecc7036bc5a7e867ba
Author: Kyrylo Tkachov <kyrylo.tkachov@arm.com>
Date: Fri Apr 4 16:10:39 2014 +0100
[ARM] Adjust arith_shiftsi for arm_restrict_it
diff --git a/gcc/config/arm/arm.md b/gcc/config/arm/arm.md
index 38ca058..9468c70 100644
--- a/gcc/config/arm/arm.md
+++ b/gcc/config/arm/arm.md
@@ -9860,6 +9860,7 @@
"TARGET_32BIT"
"%i1%?\\t%0, %2, %4%S3"
[(set_attr "predicable" "yes")
+ (set_attr "predicable_short_it" "no")
(set_attr "shift" "4")
(set_attr "arch" "a,t2,t2,a")
;; Thumb2 doesn't allow the stack pointer to be used for
Hi all, Shifted arithmetic operations can never be encoded in 16-bits in and therefore can not appear in Thumb2 IT blocks under ARMv8-A rules (and the -mrestrict-it rules). This patch adjusts the relevant pattern for that purpose. Tested and bootstrapped on arm-none-linux-gnueabihf and made sure no performance regressions on a number of benchmarks. This is a bug (not wrong-code though) in -mrestrict-it that affects 4.9 as well as trunk, so is it ok to backport it there? Thanks, Kyrill 2014-05-15 Kyrylo Tkachov <kyrylo.tkachov@arm.com> * config/arm/arm.md (arith_shiftsi): Do not predicate for arm_restrict_it.