lkml.org 
[lkml]   [2018]   [Apr]   [17]   [last100]   RSS Feed
Views: [wrap][no wrap]   [headers]  [forward] 
 
Messages in this thread
Patch in this message
/
From
Subject[PATCH v2 1/2] powerpc: avoid an unnecessary test and branch in longjmp()
Date
Doing the test at exit of the function avoids an unnecessary
test and branch inside longjmp()

Signed-off-by: Christophe Leroy <christophe.leroy@c-s.fr>
---
v2: Swapped both patches in the serie to reduce number of impacted lines

arch/powerpc/kernel/misc.S | 9 ++++-----
1 file changed, 4 insertions(+), 5 deletions(-)

diff --git a/arch/powerpc/kernel/misc.S b/arch/powerpc/kernel/misc.S
index e1f3a5d054c4..746ee0320ad4 100644
--- a/arch/powerpc/kernel/misc.S
+++ b/arch/powerpc/kernel/misc.S
@@ -74,10 +74,7 @@ _GLOBAL(setjmp)
blr

_GLOBAL(longjmp)
- PPC_LCMPI r4,0
- bne 1f
- li r4,1
-1: PPC_LL r13,4*SZL(r3)
+ PPC_LL r13,4*SZL(r3)
PPC_LL r14,5*SZL(r3)
PPC_LL r15,6*SZL(r3)
PPC_LL r16,7*SZL(r3)
@@ -102,7 +99,9 @@ _GLOBAL(longjmp)
PPC_LL r1,SZL(r3)
PPC_LL r2,2*SZL(r3)
mtlr r0
- mr r3,r4
+ mr. r3, r4
+ bnelr
+ li r3, 1
blr

_GLOBAL(current_stack_pointer)
--
2.13.3
\
 
 \ /
  Last update: 2018-04-17 19:10    [W:0.089 / U:0.160 seconds]
©2003-2020 Jasper Spaans|hosted at Digital Ocean and TransIP|Read the blog|Advertise on this site