diff options
Diffstat (limited to 'sysdeps/s390/s390-32/bcopy.S')
| -rw-r--r-- | sysdeps/s390/s390-32/bcopy.S | 54 |
1 files changed, 30 insertions, 24 deletions
diff --git a/sysdeps/s390/s390-32/bcopy.S b/sysdeps/s390/s390-32/bcopy.S index 8bf5bbb..526e336 100644 --- a/sysdeps/s390/s390-32/bcopy.S +++ b/sysdeps/s390/s390-32/bcopy.S @@ -1,4 +1,4 @@ -/* bcopy -- copy a block from source to destination. For IBM S390 +/* bcopy -- copy a block from source to destination. S/390 version. This file is part of the GNU C Library. Copyright (C) 2000, 2001 Free Software Foundation, Inc. Contributed by Martin Schwidefsky (schwidefsky@de.ibm.com). @@ -18,48 +18,53 @@ write to the Free Software Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. */ -/* - * R2 = address of source - * R3 = address of destination - * R4 = number of bytes to copy - */ +/* INPUT PARAMETERS + %r2 = address of source + %r3 = address of destination + %r4 = number of bytes to copy. */ #include "sysdep.h" #include "asm-syntax.h" .text ENTRY(__bcopy) + ltr %r1,%r4 # zero bcopy ? + jz .L4 clr %r2,%r3 # check against destructive overlap jnl .L0 - lr %r1,%r2 - alr %r1,%r4 + alr %r1,%r2 clr %r1,%r3 - jh .L2 -.L0: - lr %r5,%r4 # source length - lr %r4,%r2 # source address - sr %r1,%r1 # set pad byte to zero - lr %r2,%r3 # set destination - lr %r3,%r5 # destination length = source length -.L1: mvcle %r2,%r4,0(%r1) # thats it, MVCLE is your friend - jo .L1 - br %r14 -.L2: # destructive overlay, can not use mvcle + jh .L5 +.L0: ahi %r4,-1 # length - 1 + lr %r1,%r4 + srl %r1,8 + ltr %r1,%r1 + jz .L2 +.L1: mvc 0(256,%r3),0(%r2) # move in 256 byte chunks + la %r2,256(%r2) + la %r3,256(%r3) + brct %r1,.L1 +.L2: bras %r1,.L3 # setup base pointer for execute + mvc 0(1,%r3),0(%r2) # instruction for execute +.L3: ex %r4,0(%r1) # execute mvc with length ((%r4)&255)+1 +.L4: br %r14 + +.L5: # destructive overlay, can not use mvcle lr %r1,%r2 # bcopy is called with source,dest lr %r2,%r3 # memmove with dest,source! Oh, well... lr %r3,%r1 basr %r1,0 -.L3: +.L6: #ifdef PIC - al %r1,.L4-.L3(%r1) # get address of global offset table + al %r1,.L7-.L6(%r1) # get address of global offset table # load address of memmove l %r1,memmove@GOT12(%r1) br %r1 -.L4: .long _GLOBAL_OFFSET_TABLE_-.L3 +.L7: .long _GLOBAL_OFFSET_TABLE_-.L6 #else - al %r1,.L4-.L3(%r1) # load address of memmove + al %r1,.L7-.L6(%r1) # load address of memmove br %r1 # jump to memmove -.L4: .long memmove-.L3 +.L7: .long memmove-.L6 #endif END(__bcopy) @@ -67,3 +72,4 @@ END(__bcopy) #ifndef NO_WEAK_ALIAS weak_alias (__bcopy, bcopy) #endif + |