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;===========================================================================
; Copyright (c) 1990-1999 Info-ZIP. All rights reserved.
;
; See the accompanying file LICENSE, version 1999-Oct-05 or later
; (the contents of which are also included in zip.h) for terms of use.
; If, for some reason, both of these files are missing, the Info-ZIP license
; also may be found at: ftp://ftp.cdrom.com/pub/infozip/license.html
;===========================================================================
; sendbits.s for ARM by Sergio Monesi and Darren Salt.
r0 RN 0
r1 RN 1
r2 RN 2
r3 RN 3
r4 RN 4
r5 RN 5
r6 RN 6
r7 RN 7
r8 RN 8
r9 RN 9
sl RN 10
fp RN 11
ip RN 12
sp RN 13
lr RN 14
pc RN 15
AREA |Asm$$Code|, CODE, READONLY
= "send_bits",0
ALIGN
& &FF00000C
IMPORT __rt_stkovf_split_small
IMPORT flush_outbuf
IMPORT bi_valid
IMPORT bi_buf
IMPORT out_size
IMPORT out_offset
IMPORT out_buf
EXPORT send_bits
send_bits
MOV ip,sp
STMDB sp!,{r4,r5,fp,ip,lr,pc}
SUB fp,ip,#4
LDR r5,=bi_buf
LDR r3,=bi_valid
LDR r4,[r5]
LDR r2,[r3]
ORR r4,r4,r0,LSL r2 ; |= value<<bi_valid
ADD r2,r2,r1 ; += length
CMP r2,#&10
STRLE r2,[r3] ; short? store & return
STRLE r4,[r5]
LDMLEDB fp,{r4,r5,fp,sp,pc}^
SUB r2,r2,#&10 ; adjust bi_valid, bi_buf
MOV ip,r4,LSR #16 ; (done early, keeping the old bi_buf
STR r2,[r3] ; in R4 for later storage)
STR ip,[r5]
LDR r0,=out_size
LDR r1,=out_offset
LDR r0,[r0]
LDR r2,[r1]
SUB r0,r0,#1
CMP r2,r0 ; if out_offset >= out_size-1
LDRHS r0,=out_buf
LDRHS r0,[r0]
BLHS flush_outbuf ; then flush the buffer
LDR r0,=out_buf
LDR r1,=out_offset
LDR r0,[r0]
LDR r2,[r1]
MOV r5,r4,LSR #8
STRB r4,[r0,r2]! ; store 'old' bi_buf
STRB r5,[r0,#1]
ADD r2,r2,#2
STR r2,[r1]
LDMDB fp,{r4,r5,fp,sp,pc}^
ptr_bi & bi_valid
& bi_buf
= "bi_reverse",0
ALIGN
& &FF00000C
EXPORT bi_reverse
bi_reverse
MOV r2,#0
loop MOVS r0,r0,LSR #1
ADCS r2,r2,r2
SUBS r1,r1,#1
BNE loop
MOV r0,r2
MOVS pc,lr
END
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