aboutsummaryrefslogtreecommitdiffstats
path: root/arch/sparc/lib
diff options
context:
space:
mode:
authorSam Ravnborg <sam@ravnborg.org>2017-08-04 19:59:39 +0200
committerDavid S. Miller <davem@davemloft.net>2017-08-10 14:53:07 -0700
commit061273f9ecdb9e55e80676bbbb8f65ecd3b9699a (patch)
tree094f7afd584b7c4b77a7e17c052e897f90c3f78a /arch/sparc/lib
parentMerge git://git.kernel.org/pub/scm/linux/kernel/git/davem/sparc (diff)
downloadlinux-dev-061273f9ecdb9e55e80676bbbb8f65ecd3b9699a.tar.xz
linux-dev-061273f9ecdb9e55e80676bbbb8f65ecd3b9699a.zip
sparc64: update comments in U3memcpy
Update comments about the range the different parts of the code copies, the original comments were wrong. Introduce a few descriptive labels too. No functional changes. Signed-off-by: Sam Ravnborg <sam@ravnborg.org> Signed-off-by: David S. Miller <davem@davemloft.net>
Diffstat (limited to 'arch/sparc/lib')
-rw-r--r--arch/sparc/lib/U3memcpy.S32
1 files changed, 21 insertions, 11 deletions
diff --git a/arch/sparc/lib/U3memcpy.S b/arch/sparc/lib/U3memcpy.S
index 5a8cb37f0a3b..f9b42b3c63b0 100644
--- a/arch/sparc/lib/U3memcpy.S
+++ b/arch/sparc/lib/U3memcpy.S
@@ -168,18 +168,25 @@ ENDPROC(U3_retl_o2_and_7_plus_GS_plus_8)
FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */
srlx %o2, 31, %g2
cmp %g2, 0
+
+ /* software trap 5 "Range Check" if dst >= 0x80000000 */
tne %xcc, 5
PREAMBLE
mov %o0, %o4
+
+ /* if len == 0 */
cmp %o2, 0
- be,pn %XCC, 85f
+ be,pn %XCC, end_return
or %o0, %o1, %o3
+
+ /* if len < 16 */
cmp %o2, 16
- blu,a,pn %XCC, 80f
+ blu,a,pn %XCC, less_than_16
or %o3, %o2, %o3
+ /* if len < 192 */
cmp %o2, (3 * 64)
- blu,pt %XCC, 70f
+ blu,pt %XCC, less_than_192
andcc %o3, 0x7, %g0
/* Clobbers o5/g1/g2/g3/g7/icc/xcc. We must preserve
@@ -362,7 +369,7 @@ FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */
cmp %o2, 0
add %o1, %g1, %o1
VISExitHalf
- be,pn %XCC, 85f
+ be,pn %XCC, end_return
sub %o0, %o1, %o3
andcc %g1, 0x7, %g0
@@ -392,14 +399,15 @@ FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */
sub %o2, 2, %o2
1: andcc %o2, 0x1, %g0
- be,pt %icc, 85f
+ be,pt %icc, end_return
nop
EX_LD(LOAD(ldub, %o1, %o5), U3_retl_o2)
- ba,pt %xcc, 85f
+ ba,pt %xcc, end_return
EX_ST(STORE(stb, %o5, %o1 + %o3), U3_retl_o2)
.align 64
-70: /* 16 < len <= 64 */
+ /* 16 <= len < 192 */
+less_than_192:
bne,pn %XCC, 75f
sub %o0, %o1, %o3
@@ -429,7 +437,7 @@ FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */
EX_ST(STORE(stw, %o5, %o1 + %o3), U3_retl_o2_plus_4)
add %o1, 0x4, %o1
1: cmp %o2, 0
- be,pt %XCC, 85f
+ be,pt %XCC, end_return
nop
ba,pt %xcc, 90f
nop
@@ -475,13 +483,14 @@ FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */
srl %g1, 3, %g1
andcc %o2, 0x7, %o2
- be,pn %icc, 85f
+ be,pn %icc, end_return
add %o1, %g1, %o1
ba,pt %xcc, 90f
sub %o0, %o1, %o3
.align 64
-80: /* 0 < len <= 16 */
+ /* 0 < len < 16 */
+less_than_16:
andcc %o3, 0x3, %g0
bne,pn %XCC, 90f
sub %o0, %o1, %o3
@@ -493,7 +502,8 @@ FUNC_NAME: /* %o0=dst, %o1=src, %o2=len */
bgu,pt %XCC, 1b
add %o1, 4, %o1
-85: retl
+end_return:
+ retl
mov EX_RETVAL(%o4), %o0
.align 32