minix/common/lib/libc/arch/arm/quad/__aeabi_ldivmod.S

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/*-
* Copyright (c) 2012 The NetBSD Foundation, Inc.
* All rights reserved.
*
* This code is derived from software contributed to The NetBSD Foundation
* by Matt Thomas of 3am Software Foundry.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. 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.
*
* THIS SOFTWARE IS PROVIDED BY THE NETBSD FOUNDATION, INC. 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 FOUNDATION 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.
*/
#include <machine/asm.h>
RCSID("$NetBSD: __aeabi_ldivmod.S,v 1.12 2013/08/19 03:27:34 matt Exp $")
#ifdef __ARMEB__
#define ALO r1 /* incoming numerator, outgoing quotient */
#define AHI r0 /* incoming numerator, outgoing quotient */
#define BLO r3 /* incoming denominator, outgoing remainder */
#define BHI r2 /* incoming denominator, outgoing remainder */
#else
#define ALO r0 /* incoming numerator, outgoing quotient */
#define AHI r1 /* incoming numerator, outgoing quotient */
#define BLO r2 /* incoming denominator, outgoing remainder */
#define BHI r3 /* incoming denominator, outgoing remainder */
#endif
ENTRY(__aeabi_ldivmod)
#ifdef __ARM_EABI__
.fnstart
.cfi_startproc
#endif
#if !defined(_KERNEL) && !defined(_STANDALONE)
#if !defined(__thumb__)
orrs ip, BLO, BHI
beq .Ldivbyzero
#elif defined(_ARM_ARCH_T2)
cbnz BLO, 1f
cbz BHI, .Ldivbyzero
#else
cmp BLO, #0
bne 1f
cmp BHI, #0
beq .Ldivbyzero
#endif
1:
#endif
push {r4-r6, lr}
#ifdef __ARM_EABI__
.cfi_def_cfa_offset 16
.cfi_offset 14, -4
.cfi_offset 6, -8
.cfi_offset 5, -12
.cfi_offset 4, -16
#endif
#define NEG r5
movs NEG, #0
cmp BHI, #0
bge 2f
movs NEG, #1 /* flip quotient sign */
bl .Lnegate_b
bcs .Lmaxdenom
2:
cmp AHI, #0
#ifdef __thumb__
bge 3f
movs r4, #3
eors NEG, NEG, r4 /* flip quotient sign, flip remainder sign */
bl .Lnegate_a
3:
#else
eorlt NEG, NEG, #3 /* flip quotient sign, flip remainder sign */
bllt .Lnegate_a
#endif
/*
* Arguments are setup, allocate some stack for the remainder
* and call __qdivrem for the heavy lifting.
*/
#ifdef __ARM_EABI__
.cfi_def_cfa_offset 32
#endif
sub sp, sp, #16
#if !defined(__thumb__) || defined(_ARM_ARCH_T2)
adds r4, sp, #8
#else
mov r4, sp
adds r4, r4, #8
#endif
str r4, [sp]
bl PLT_SYM(__qdivrem)
add sp, sp, #8
#ifdef __ARM_EABI__
.cfi_def_cfa_offset 24
.cfi_offset 3, -20
.cfi_offset 2, -24
#endif
/*
* The quotient is already in the right place and neither value
* needs its sign flipped.
*/
#if defined(__thumb__) && defined(_ARM_ARCH_T2)
cbz NEG, .Lnegate_neither
#else
cmp NEG, #0 /* any signs to flip? */
beq .Lnegate_neither
#endif
cmp NEG, #2 /* does remainder need to be negative? */
beq .Lnegate_b_only /* 2 means b only */
bgt .Lnegate_both /* 3 means both */
.Lnegate_a_only:
bl .Lnegate_a /* 1 means a only */
.Lnegate_neither:
pop {r2-r6, pc} /* grab b from stack */
.Lnegate_both:
bl .Lnegate_a
.Lnegate_b_only:
pop {r2-r3} /* get remainder */
#ifdef __ARM_EABI__
.cfi_def_cfa_offset 16
#endif
bl .Lnegate_b /* negate it */
pop {r4-r6, pc}
.align 0
.Lnegate_a:
#ifdef __thumb__
movs r4, AHI
movs AHI, #0
negs ALO, ALO
sbcs AHI, AHI, r4
#else
negs ALO, ALO
rsc AHI, AHI, #0
#endif
RET
.align 0
.Lnegate_b:
#ifdef __thumb__
movs r4, BHI
movs BHI, #0
negs BLO, BLO
sbcs BHI, BHI, r4
#else
negs BLO, BLO
rsc BHI, BHI, #0
#endif
RET
.align 0
.Lmaxdenom:
/*
* We had a carry so the denominator must have INT64_MIN
* Also BLO and BHI never changed values so we can use
* them to see if the numerator has the same value. We
* don't have to worry about sign.
*/
cmp BHI, AHI
#ifdef __thumb__
bne 1f
cmp BLO, ALO
#else
cmpeq BLO, ALO
#endif
bne 1f
/*
* They were equal, so we return a quotient of 1 and remainder of 0.
*/
movs ALO, #1
movs AHI, #0
movs BLO, #0
movs BHI, #0
pop {r4-r6, pc}
/*
* Our remainder must be the numerator and our quotient is 0.
*/
.align 0
1: movs BLO, ALO
movs BHI, AHI
movs ALO, #0
movs AHI, #0
pop {r4-r6, pc}
#if !defined(_KERNEL) && !defined(_STANDALONE)
.align 0
.Ldivbyzero:
push {r0-r1,r4,lr}
#ifdef __ARM_EABI__
.save {r0-r1,r4,lr}
.cfi_def_cfa_offset 16
.cfi_offset 14, -4
.cfi_offset 4, -8
#endif
cmp AHI, #0
#if !defined(__thumb__) || defined(_ARM_ARCH_T2)
#ifdef __thumb__
ittee ge
#endif
mvnge ALO, #0
mvnge AHI, #0x80000000
movlt ALO, #0
movlt AHI, #0x80000000
#else
blt 1f
movs ALO, #0
mvns ALO, ALO
mov AHI, ALO
lsrs AHI, AHI, #1
b 2f
1:
movs ALO, #0
movs AHI, #1
lsls AHI, AHI, #31
2:
#endif /* __thumb__ && !_ARM_ARCH_T2 */
bl PLT_SYM(__aeabi_ldiv0)
pop {r2-r4, pc}
#endif /* !_KERNEL && !_STANDALONE */
#ifdef __ARM_EABI__
.cfi_endproc
.fnend
#endif
END(__aeabi_ldivmod)