Commit 551f4134 authored by Heiko Carstens's avatar Heiko Carstens Committed by Martin Schwidefsky
Browse files

s390/lib: improve memmove, memset and memcpy 



Improve the memmove implementation to save one instruction and use
better label names. Also use better label names for the memset and
memcpy implementations so everything looks consistent.

Suggested-by: default avatarJens Remus <jremus@linux.vnet.ibm.com>
Signed-off-by: default avatarHeiko Carstens <heiko.carstens@de.ibm.com>
Signed-off-by: default avatarMartin Schwidefsky <schwidefsky@de.ibm.com>
parent e3850ecf

arch/s390/lib/mem.S

+13 −15
Original line number Diff line number Diff line
@@ -14,31 +14,29 @@ ENTRY(memmove) 
	ltgr	%r4,%r4

	lgr	%r1,%r2

	bzr	%r14

	aghi	%r4,-1

	clgr	%r2,%r3

	jnh	.Lmemmove_forward

	la	%r5,0(%r4,%r3)

	la	%r5,1(%r4,%r3)

	clgr	%r2,%r5

	jl	.Lmemmove_reverse

.Lmemmove_forward:

	aghi	%r4,-1

	srlg	%r0,%r4,8

	ltgr	%r0,%r0

	jz	.Lmemmove_rest

.Lmemmove_loop:

	jz	.Lmemmove_forward_remainder

.Lmemmove_forward_loop:

	mvc	0(256,%r1),0(%r3)

	la	%r1,256(%r1)

	la	%r3,256(%r3)

	brctg	%r0,.Lmemmove_loop

.Lmemmove_rest:

	brctg	%r0,.Lmemmove_forward_loop

.Lmemmove_forward_remainder:

	larl	%r5,.Lmemmove_mvc

	ex	%r4,0(%r5)

	br	%r14

.Lmemmove_reverse:

	aghi	%r4,-1

.Lmemmove_reverse_loop:

	ic	%r0,0(%r4,%r3)

	stc	%r0,0(%r4,%r1)

	brctg	%r4,.Lmemmove_reverse_loop

	brctg	%r4,.Lmemmove_reverse

	ic	%r0,0(%r4,%r3)

	stc	%r0,0(%r4,%r1)

	br	%r14
@@ -70,12 +68,12 @@ ENTRY(memset) 
	srlg	%r3,%r4,8

	ltgr	%r3,%r3

	lgr	%r1,%r2

	jz	.Lmemset_clear_rest

	jz	.Lmemset_clear_remainder

.Lmemset_clear_loop:

	xc	0(256,%r1),0(%r1)

	la	%r1,256(%r1)

	brctg	%r3,.Lmemset_clear_loop

.Lmemset_clear_rest:

.Lmemset_clear_remainder:

	larl	%r3,.Lmemset_xc

	ex	%r4,0(%r3)

	br	%r14
@@ -87,12 +85,12 @@ ENTRY(memset) 
	aghi	%r4,-2

	srlg	%r3,%r4,8

	ltgr	%r3,%r3

	jz	.Lmemset_fill_rest

	jz	.Lmemset_fill_remainder

.Lmemset_fill_loop:

	mvc	1(256,%r1),0(%r1)

	la	%r1,256(%r1)

	brctg	%r3,.Lmemset_fill_loop

.Lmemset_fill_rest:

.Lmemset_fill_remainder:

	larl	%r3,.Lmemset_mvc

	ex	%r4,0(%r3)

	br	%r14
@@ -115,7 +113,7 @@ ENTRY(memcpy) 
	ltgr	%r5,%r5

	lgr	%r1,%r2

	jnz	.Lmemcpy_loop

.Lmemcpy_rest:

.Lmemcpy_remainder:

	larl	%r5,.Lmemcpy_mvc

	ex	%r4,0(%r5)

	br	%r14
@@ -124,7 +122,7 @@ ENTRY(memcpy) 
	la	%r1,256(%r1)

	la	%r3,256(%r3)

	brctg	%r5,.Lmemcpy_loop

	j	.Lmemcpy_rest

	j	.Lmemcpy_remainder

.Lmemcpy_mvc:

	mvc	0(1,%r1),0(%r3)

EXPORT_SYMBOL(memcpy)

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