blob: 981e86bb515e0b8906d4a46acee914a9b9364f2f [file] [log] [blame]
@ Tremolo library
@-----------------------------------------------------------------------
@ Copyright (C) 2002-2009, Xiph.org Foundation
@ Copyright (C) 2010, Robin Watts for Pinknoise Productions Ltd
@ All rights reserved.
@ Redistribution and use in source and binary forms, with or without
@ modification, are permitted provided that the following conditions
@ are met:
@ * Redistributions of source code must retain the above copyright
@ notice, this list of conditions and the following disclaimer.
@ * Redistributions in binary form must reproduce the above
@ copyright notice, this list of conditions and the following disclaimer
@ in the documentation and/or other materials provided with the
@ distribution.
@ * Neither the names of the Xiph.org Foundation nor Pinknoise
@ Productions Ltd nor the names of its contributors may be used to
@ endorse or promote products derived from this software without
@ specific prior written permission.
@
@ THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
@ "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
@ LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
@ A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
@ OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
@ SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
@ LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
@ DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
@ THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
@ (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
@ OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
@ ----------------------------------------------------------------------
.text
.global render_lineARM
render_lineARM:
@ r0 = n
@ r1 = d
@ r2 = floor
@ r3 = base
@ <> = err
@ <> = adx
@ <> = ady
MOV r12,r13
STMFD r13!,{r4-r6,r11,r14}
LDMFD r12,{r11,r12,r14} @ r11 = err
@ r12 = adx
@ r14 = ady
rl_loop:
LDR r4,[r1] @ r4 = *d
LDR r5,[r2],r3,LSL #2 @ r5 = *floor r2 = floor+base
SUBS r11,r11,r14 @ err -= ady
ADDLT r11,r11,r12 @ if (err < 0) err+=adx
SMULL r6, r5, r4, r5 @ (r6,r5) = *d * *floor
ADDLT r2, r2, #4 @ floor+=1
MOVS r6, r6, LSR #15
ADC r5, r6, r5, LSL #17 @ r5 = MULT31_SHIFT15
STR r5,[r1],#4
SUBS r0, r0, #1
BGT rl_loop
LDMFD r13!,{r4-r6,r11,PC}
@ END