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freebsd-skq/contrib/gcc/config/arm/lib1funcs.asm
kan 1f9ea4d0a4 GCC 4.2.0 release.
2007-05-19 01:19:51 +00:00

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@ libgcc routines for ARM cpu.
@ Division routines, written by Richard Earnshaw, (rearnsha@armltd.co.uk)
/* Copyright 1995, 1996, 1998, 1999, 2000, 2003, 2004, 2005
Free Software Foundation, Inc.
This file is free software; you can redistribute it and/or modify it
under the terms of the GNU General Public License as published by the
Free Software Foundation; either version 2, or (at your option) any
later version.
In addition to the permissions in the GNU General Public License, the
Free Software Foundation gives you unlimited permission to link the
compiled version of this file into combinations with other programs,
and to distribute those combinations without any restriction coming
from the use of this file. (The General Public License restrictions
do apply in other respects; for example, they cover modification of
the file, and distribution when not linked into a combine
executable.)
This file is distributed in the hope that it will be useful, but
WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program; see the file COPYING. If not, write to
the Free Software Foundation, 51 Franklin Street, Fifth Floor,
Boston, MA 02110-1301, USA. */
/* ------------------------------------------------------------------------ */
/* We need to know what prefix to add to function names. */
#ifndef __USER_LABEL_PREFIX__
#error __USER_LABEL_PREFIX__ not defined
#endif
/* ANSI concatenation macros. */
#define CONCAT1(a, b) CONCAT2(a, b)
#define CONCAT2(a, b) a ## b
/* Use the right prefix for global labels. */
#define SYM(x) CONCAT1 (__USER_LABEL_PREFIX__, x)
#ifdef __ELF__
#ifdef __thumb__
#define __PLT__ /* Not supported in Thumb assembler (for now). */
#else
#define __PLT__ (PLT)
#endif
#define TYPE(x) .type SYM(x),function
#define SIZE(x) .size SYM(x), . - SYM(x)
#define LSYM(x) .x
#else
#define __PLT__
#define TYPE(x)
#define SIZE(x)
#define LSYM(x) x
#endif
/* Function end macros. Variants for interworking. */
@ This selects the minimum architecture level required.
#define __ARM_ARCH__ 3
#if defined(__ARM_ARCH_3M__) || defined(__ARM_ARCH_4__) \
|| defined(__ARM_ARCH_4T__)
/* We use __ARM_ARCH__ set to 4 here, but in reality it's any processor with
long multiply instructions. That includes v3M. */
# undef __ARM_ARCH__
# define __ARM_ARCH__ 4
#endif
#if defined(__ARM_ARCH_5__) || defined(__ARM_ARCH_5T__) \
|| defined(__ARM_ARCH_5E__) || defined(__ARM_ARCH_5TE__) \
|| defined(__ARM_ARCH_5TEJ__)
# undef __ARM_ARCH__
# define __ARM_ARCH__ 5
#endif
#if defined(__ARM_ARCH_6__) || defined(__ARM_ARCH_6J__) \
|| defined(__ARM_ARCH_6K__) || defined(__ARM_ARCH_6Z__) \
|| defined(__ARM_ARCH_6ZK__)
# undef __ARM_ARCH__
# define __ARM_ARCH__ 6
#endif
#ifndef __ARM_ARCH__
#error Unable to determine architecture.
#endif
/* How to return from a function call depends on the architecture variant. */
#if (__ARM_ARCH__ > 4) || defined(__ARM_ARCH_4T__)
# define RET bx lr
# define RETc(x) bx##x lr
/* Special precautions for interworking on armv4t. */
# if (__ARM_ARCH__ == 4)
/* Always use bx, not ldr pc. */
# if (defined(__thumb__) || defined(__THUMB_INTERWORK__))
# define __INTERWORKING__
# endif /* __THUMB__ || __THUMB_INTERWORK__ */
/* Include thumb stub before arm mode code. */
# if defined(__thumb__) && !defined(__THUMB_INTERWORK__)
# define __INTERWORKING_STUBS__
# endif /* __thumb__ && !__THUMB_INTERWORK__ */
#endif /* __ARM_ARCH == 4 */
#else
# define RET mov pc, lr
# define RETc(x) mov##x pc, lr
#endif
.macro cfi_pop advance, reg, cfa_offset
#ifdef __ELF__
.pushsection .debug_frame
.byte 0x4 /* DW_CFA_advance_loc4 */
.4byte \advance
.byte (0xc0 | \reg) /* DW_CFA_restore */
.byte 0xe /* DW_CFA_def_cfa_offset */
.uleb128 \cfa_offset
.popsection
#endif
.endm
.macro cfi_push advance, reg, offset, cfa_offset
#ifdef __ELF__
.pushsection .debug_frame
.byte 0x4 /* DW_CFA_advance_loc4 */
.4byte \advance
.byte (0x80 | \reg) /* DW_CFA_offset */
.uleb128 (\offset / -4)
.byte 0xe /* DW_CFA_def_cfa_offset */
.uleb128 \cfa_offset
.popsection
#endif
.endm
.macro cfi_start start_label, end_label
#ifdef __ELF__
.pushsection .debug_frame
LSYM(Lstart_frame):
.4byte LSYM(Lend_cie) - LSYM(Lstart_cie) @ Length of CIE
LSYM(Lstart_cie):
.4byte 0xffffffff @ CIE Identifier Tag
.byte 0x1 @ CIE Version
.ascii "\0" @ CIE Augmentation
.uleb128 0x1 @ CIE Code Alignment Factor
.sleb128 -4 @ CIE Data Alignment Factor
.byte 0xe @ CIE RA Column
.byte 0xc @ DW_CFA_def_cfa
.uleb128 0xd
.uleb128 0x0
.align 2
LSYM(Lend_cie):
.4byte LSYM(Lend_fde)-LSYM(Lstart_fde) @ FDE Length
LSYM(Lstart_fde):
.4byte LSYM(Lstart_frame) @ FDE CIE offset
.4byte \start_label @ FDE initial location
.4byte \end_label-\start_label @ FDE address range
.popsection
#endif
.endm
.macro cfi_end end_label
#ifdef __ELF__
.pushsection .debug_frame
.align 2
LSYM(Lend_fde):
.popsection
\end_label:
#endif
.endm
/* Don't pass dirn, it's there just to get token pasting right. */
.macro RETLDM regs=, cond=, unwind=, dirn=ia
#if defined (__INTERWORKING__)
.ifc "\regs",""
ldr\cond lr, [sp], #8
.else
ldm\cond\dirn sp!, {\regs, lr}
.endif
.ifnc "\unwind", ""
/* Mark LR as restored. */
97: cfi_pop 97b - \unwind, 0xe, 0x0
.endif
bx\cond lr
#else
.ifc "\regs",""
ldr\cond pc, [sp], #8
.else
ldm\cond\dirn sp!, {\regs, pc}
.endif
#endif
.endm
.macro ARM_LDIV0 name
str lr, [sp, #-8]!
98: cfi_push 98b - __\name, 0xe, -0x8, 0x8
bl SYM (__div0) __PLT__
mov r0, #0 @ About as wrong as it could be.
RETLDM unwind=98b
.endm
.macro THUMB_LDIV0 name
push { r1, lr }
98: cfi_push 98b - __\name, 0xe, -0x4, 0x8
bl SYM (__div0)
mov r0, #0 @ About as wrong as it could be.
#if defined (__INTERWORKING__)
pop { r1, r2 }
bx r2
#else
pop { r1, pc }
#endif
.endm
.macro FUNC_END name
SIZE (__\name)
.endm
.macro DIV_FUNC_END name
cfi_start __\name, LSYM(Lend_div0)
LSYM(Ldiv0):
#ifdef __thumb__
THUMB_LDIV0 \name
#else
ARM_LDIV0 \name
#endif
cfi_end LSYM(Lend_div0)
FUNC_END \name
.endm
.macro THUMB_FUNC_START name
.globl SYM (\name)
TYPE (\name)
.thumb_func
SYM (\name):
.endm
/* Function start macros. Variants for ARM and Thumb. */
#ifdef __thumb__
#define THUMB_FUNC .thumb_func
#define THUMB_CODE .force_thumb
#else
#define THUMB_FUNC
#define THUMB_CODE
#endif
.macro FUNC_START name
.text
.globl SYM (__\name)
TYPE (__\name)
.align 0
THUMB_CODE
THUMB_FUNC
SYM (__\name):
.endm
/* Special function that will always be coded in ARM assembly, even if
in Thumb-only compilation. */
#if defined(__INTERWORKING_STUBS__)
.macro ARM_FUNC_START name
FUNC_START \name
bx pc
nop
.arm
/* A hook to tell gdb that we've switched to ARM mode. Also used to call
directly from other local arm routines. */
_L__\name:
.endm
#define EQUIV .thumb_set
/* Branch directly to a function declared with ARM_FUNC_START.
Must be called in arm mode. */
.macro ARM_CALL name
bl _L__\name
.endm
#else
.macro ARM_FUNC_START name
.text
.globl SYM (__\name)
TYPE (__\name)
.align 0
.arm
SYM (__\name):
.endm
#define EQUIV .set
.macro ARM_CALL name
bl __\name
.endm
#endif
.macro FUNC_ALIAS new old
.globl SYM (__\new)
#if defined (__thumb__)
.thumb_set SYM (__\new), SYM (__\old)
#else
.set SYM (__\new), SYM (__\old)
#endif
.endm
.macro ARM_FUNC_ALIAS new old
.globl SYM (__\new)
EQUIV SYM (__\new), SYM (__\old)
#if defined(__INTERWORKING_STUBS__)
.set SYM (_L__\new), SYM (_L__\old)
#endif
.endm
#ifdef __thumb__
/* Register aliases. */
work .req r4 @ XXXX is this safe ?
dividend .req r0
divisor .req r1
overdone .req r2
result .req r2
curbit .req r3
#endif
#if 0
ip .req r12
sp .req r13
lr .req r14
pc .req r15
#endif
/* ------------------------------------------------------------------------ */
/* Bodies of the division and modulo routines. */
/* ------------------------------------------------------------------------ */
.macro ARM_DIV_BODY dividend, divisor, result, curbit
#if __ARM_ARCH__ >= 5 && ! defined (__OPTIMIZE_SIZE__)
clz \curbit, \dividend
clz \result, \divisor
sub \curbit, \result, \curbit
rsbs \curbit, \curbit, #31
addne \curbit, \curbit, \curbit, lsl #1
mov \result, #0
addne pc, pc, \curbit, lsl #2
nop
.set shift, 32
.rept 32
.set shift, shift - 1
cmp \dividend, \divisor, lsl #shift
adc \result, \result, \result
subcs \dividend, \dividend, \divisor, lsl #shift
.endr
#else /* __ARM_ARCH__ < 5 || defined (__OPTIMIZE_SIZE__) */
#if __ARM_ARCH__ >= 5
clz \curbit, \divisor
clz \result, \dividend
sub \result, \curbit, \result
mov \curbit, #1
mov \divisor, \divisor, lsl \result
mov \curbit, \curbit, lsl \result
mov \result, #0
#else /* __ARM_ARCH__ < 5 */
@ Initially shift the divisor left 3 bits if possible,
@ set curbit accordingly. This allows for curbit to be located
@ at the left end of each 4 bit nibbles in the division loop
@ to save one loop in most cases.
tst \divisor, #0xe0000000
moveq \divisor, \divisor, lsl #3
moveq \curbit, #8
movne \curbit, #1
@ Unless the divisor is very big, shift it up in multiples of
@ four bits, since this is the amount of unwinding in the main
@ division loop. Continue shifting until the divisor is
@ larger than the dividend.
1: cmp \divisor, #0x10000000
cmplo \divisor, \dividend
movlo \divisor, \divisor, lsl #4
movlo \curbit, \curbit, lsl #4
blo 1b
@ For very big divisors, we must shift it a bit at a time, or
@ we will be in danger of overflowing.
1: cmp \divisor, #0x80000000
cmplo \divisor, \dividend
movlo \divisor, \divisor, lsl #1
movlo \curbit, \curbit, lsl #1
blo 1b
mov \result, #0
#endif /* __ARM_ARCH__ < 5 */
@ Division loop
1: cmp \dividend, \divisor
subhs \dividend, \dividend, \divisor
orrhs \result, \result, \curbit
cmp \dividend, \divisor, lsr #1
subhs \dividend, \dividend, \divisor, lsr #1
orrhs \result, \result, \curbit, lsr #1
cmp \dividend, \divisor, lsr #2
subhs \dividend, \dividend, \divisor, lsr #2
orrhs \result, \result, \curbit, lsr #2
cmp \dividend, \divisor, lsr #3
subhs \dividend, \dividend, \divisor, lsr #3
orrhs \result, \result, \curbit, lsr #3
cmp \dividend, #0 @ Early termination?
movnes \curbit, \curbit, lsr #4 @ No, any more bits to do?
movne \divisor, \divisor, lsr #4
bne 1b
#endif /* __ARM_ARCH__ < 5 || defined (__OPTIMIZE_SIZE__) */
.endm
/* ------------------------------------------------------------------------ */
.macro ARM_DIV2_ORDER divisor, order
#if __ARM_ARCH__ >= 5
clz \order, \divisor
rsb \order, \order, #31
#else
cmp \divisor, #(1 << 16)
movhs \divisor, \divisor, lsr #16
movhs \order, #16
movlo \order, #0
cmp \divisor, #(1 << 8)
movhs \divisor, \divisor, lsr #8
addhs \order, \order, #8
cmp \divisor, #(1 << 4)
movhs \divisor, \divisor, lsr #4
addhs \order, \order, #4
cmp \divisor, #(1 << 2)
addhi \order, \order, #3
addls \order, \order, \divisor, lsr #1
#endif
.endm
/* ------------------------------------------------------------------------ */
.macro ARM_MOD_BODY dividend, divisor, order, spare
#if __ARM_ARCH__ >= 5 && ! defined (__OPTIMIZE_SIZE__)
clz \order, \divisor
clz \spare, \dividend
sub \order, \order, \spare
rsbs \order, \order, #31
addne pc, pc, \order, lsl #3
nop
.set shift, 32
.rept 32
.set shift, shift - 1
cmp \dividend, \divisor, lsl #shift
subcs \dividend, \dividend, \divisor, lsl #shift
.endr
#else /* __ARM_ARCH__ < 5 || defined (__OPTIMIZE_SIZE__) */
#if __ARM_ARCH__ >= 5
clz \order, \divisor
clz \spare, \dividend
sub \order, \order, \spare
mov \divisor, \divisor, lsl \order
#else /* __ARM_ARCH__ < 5 */
mov \order, #0
@ Unless the divisor is very big, shift it up in multiples of
@ four bits, since this is the amount of unwinding in the main
@ division loop. Continue shifting until the divisor is
@ larger than the dividend.
1: cmp \divisor, #0x10000000
cmplo \divisor, \dividend
movlo \divisor, \divisor, lsl #4
addlo \order, \order, #4
blo 1b
@ For very big divisors, we must shift it a bit at a time, or
@ we will be in danger of overflowing.
1: cmp \divisor, #0x80000000
cmplo \divisor, \dividend
movlo \divisor, \divisor, lsl #1
addlo \order, \order, #1
blo 1b
#endif /* __ARM_ARCH__ < 5 */
@ Perform all needed substractions to keep only the reminder.
@ Do comparisons in batch of 4 first.
subs \order, \order, #3 @ yes, 3 is intended here
blt 2f
1: cmp \dividend, \divisor
subhs \dividend, \dividend, \divisor
cmp \dividend, \divisor, lsr #1
subhs \dividend, \dividend, \divisor, lsr #1
cmp \dividend, \divisor, lsr #2
subhs \dividend, \dividend, \divisor, lsr #2
cmp \dividend, \divisor, lsr #3
subhs \dividend, \dividend, \divisor, lsr #3
cmp \dividend, #1
mov \divisor, \divisor, lsr #4
subges \order, \order, #4
bge 1b
tst \order, #3
teqne \dividend, #0
beq 5f
@ Either 1, 2 or 3 comparison/substractions are left.
2: cmn \order, #2
blt 4f
beq 3f
cmp \dividend, \divisor
subhs \dividend, \dividend, \divisor
mov \divisor, \divisor, lsr #1
3: cmp \dividend, \divisor
subhs \dividend, \dividend, \divisor
mov \divisor, \divisor, lsr #1
4: cmp \dividend, \divisor
subhs \dividend, \dividend, \divisor
5:
#endif /* __ARM_ARCH__ < 5 || defined (__OPTIMIZE_SIZE__) */
.endm
/* ------------------------------------------------------------------------ */
.macro THUMB_DIV_MOD_BODY modulo
@ Load the constant 0x10000000 into our work register.
mov work, #1
lsl work, #28
LSYM(Loop1):
@ Unless the divisor is very big, shift it up in multiples of
@ four bits, since this is the amount of unwinding in the main
@ division loop. Continue shifting until the divisor is
@ larger than the dividend.
cmp divisor, work
bhs LSYM(Lbignum)
cmp divisor, dividend
bhs LSYM(Lbignum)
lsl divisor, #4
lsl curbit, #4
b LSYM(Loop1)
LSYM(Lbignum):
@ Set work to 0x80000000
lsl work, #3
LSYM(Loop2):
@ For very big divisors, we must shift it a bit at a time, or
@ we will be in danger of overflowing.
cmp divisor, work
bhs LSYM(Loop3)
cmp divisor, dividend
bhs LSYM(Loop3)
lsl divisor, #1
lsl curbit, #1
b LSYM(Loop2)
LSYM(Loop3):
@ Test for possible subtractions ...
.if \modulo
@ ... On the final pass, this may subtract too much from the dividend,
@ so keep track of which subtractions are done, we can fix them up
@ afterwards.
mov overdone, #0
cmp dividend, divisor
blo LSYM(Lover1)
sub dividend, dividend, divisor
LSYM(Lover1):
lsr work, divisor, #1
cmp dividend, work
blo LSYM(Lover2)
sub dividend, dividend, work
mov ip, curbit
mov work, #1
ror curbit, work
orr overdone, curbit
mov curbit, ip
LSYM(Lover2):
lsr work, divisor, #2
cmp dividend, work
blo LSYM(Lover3)
sub dividend, dividend, work
mov ip, curbit
mov work, #2
ror curbit, work
orr overdone, curbit
mov curbit, ip
LSYM(Lover3):
lsr work, divisor, #3
cmp dividend, work
blo LSYM(Lover4)
sub dividend, dividend, work
mov ip, curbit
mov work, #3
ror curbit, work
orr overdone, curbit
mov curbit, ip
LSYM(Lover4):
mov ip, curbit
.else
@ ... and note which bits are done in the result. On the final pass,
@ this may subtract too much from the dividend, but the result will be ok,
@ since the "bit" will have been shifted out at the bottom.
cmp dividend, divisor
blo LSYM(Lover1)
sub dividend, dividend, divisor
orr result, result, curbit
LSYM(Lover1):
lsr work, divisor, #1
cmp dividend, work
blo LSYM(Lover2)
sub dividend, dividend, work
lsr work, curbit, #1
orr result, work
LSYM(Lover2):
lsr work, divisor, #2
cmp dividend, work
blo LSYM(Lover3)
sub dividend, dividend, work
lsr work, curbit, #2
orr result, work
LSYM(Lover3):
lsr work, divisor, #3
cmp dividend, work
blo LSYM(Lover4)
sub dividend, dividend, work
lsr work, curbit, #3
orr result, work
LSYM(Lover4):
.endif
cmp dividend, #0 @ Early termination?
beq LSYM(Lover5)
lsr curbit, #4 @ No, any more bits to do?
beq LSYM(Lover5)
lsr divisor, #4
b LSYM(Loop3)
LSYM(Lover5):
.if \modulo
@ Any subtractions that we should not have done will be recorded in
@ the top three bits of "overdone". Exactly which were not needed
@ are governed by the position of the bit, stored in ip.
mov work, #0xe
lsl work, #28
and overdone, work
beq LSYM(Lgot_result)
@ If we terminated early, because dividend became zero, then the
@ bit in ip will not be in the bottom nibble, and we should not
@ perform the additions below. We must test for this though
@ (rather relying upon the TSTs to prevent the additions) since
@ the bit in ip could be in the top two bits which might then match
@ with one of the smaller RORs.
mov curbit, ip
mov work, #0x7
tst curbit, work
beq LSYM(Lgot_result)
mov curbit, ip
mov work, #3
ror curbit, work
tst overdone, curbit
beq LSYM(Lover6)
lsr work, divisor, #3
add dividend, work
LSYM(Lover6):
mov curbit, ip
mov work, #2
ror curbit, work
tst overdone, curbit
beq LSYM(Lover7)
lsr work, divisor, #2
add dividend, work
LSYM(Lover7):
mov curbit, ip
mov work, #1
ror curbit, work
tst overdone, curbit
beq LSYM(Lgot_result)
lsr work, divisor, #1
add dividend, work
.endif
LSYM(Lgot_result):
.endm
/* ------------------------------------------------------------------------ */
/* Start of the Real Functions */
/* ------------------------------------------------------------------------ */
#ifdef L_udivsi3
FUNC_START udivsi3
FUNC_ALIAS aeabi_uidiv udivsi3
#ifdef __thumb__
cmp divisor, #0
beq LSYM(Ldiv0)
mov curbit, #1
mov result, #0
push { work }
cmp dividend, divisor
blo LSYM(Lgot_result)
THUMB_DIV_MOD_BODY 0
mov r0, result
pop { work }
RET
#else /* ARM version. */
subs r2, r1, #1
RETc(eq)
bcc LSYM(Ldiv0)
cmp r0, r1
bls 11f
tst r1, r2
beq 12f
ARM_DIV_BODY r0, r1, r2, r3
mov r0, r2
RET
11: moveq r0, #1
movne r0, #0
RET
12: ARM_DIV2_ORDER r1, r2
mov r0, r0, lsr r2
RET
#endif /* ARM version */
DIV_FUNC_END udivsi3
FUNC_START aeabi_uidivmod
#ifdef __thumb__
push {r0, r1, lr}
bl SYM(__udivsi3)
POP {r1, r2, r3}
mul r2, r0
sub r1, r1, r2
bx r3
#else
stmfd sp!, { r0, r1, lr }
bl SYM(__udivsi3)
ldmfd sp!, { r1, r2, lr }
mul r3, r2, r0
sub r1, r1, r3
RET
#endif
FUNC_END aeabi_uidivmod
#endif /* L_udivsi3 */
/* ------------------------------------------------------------------------ */
#ifdef L_umodsi3
FUNC_START umodsi3
#ifdef __thumb__
cmp divisor, #0
beq LSYM(Ldiv0)
mov curbit, #1
cmp dividend, divisor
bhs LSYM(Lover10)
RET
LSYM(Lover10):
push { work }
THUMB_DIV_MOD_BODY 1
pop { work }
RET
#else /* ARM version. */
subs r2, r1, #1 @ compare divisor with 1
bcc LSYM(Ldiv0)
cmpne r0, r1 @ compare dividend with divisor
moveq r0, #0
tsthi r1, r2 @ see if divisor is power of 2
andeq r0, r0, r2
RETc(ls)
ARM_MOD_BODY r0, r1, r2, r3
RET
#endif /* ARM version. */
DIV_FUNC_END umodsi3
#endif /* L_umodsi3 */
/* ------------------------------------------------------------------------ */
#ifdef L_divsi3
FUNC_START divsi3
FUNC_ALIAS aeabi_idiv divsi3
#ifdef __thumb__
cmp divisor, #0
beq LSYM(Ldiv0)
push { work }
mov work, dividend
eor work, divisor @ Save the sign of the result.
mov ip, work
mov curbit, #1
mov result, #0
cmp divisor, #0
bpl LSYM(Lover10)
neg divisor, divisor @ Loops below use unsigned.
LSYM(Lover10):
cmp dividend, #0
bpl LSYM(Lover11)
neg dividend, dividend
LSYM(Lover11):
cmp dividend, divisor
blo LSYM(Lgot_result)
THUMB_DIV_MOD_BODY 0
mov r0, result
mov work, ip
cmp work, #0
bpl LSYM(Lover12)
neg r0, r0
LSYM(Lover12):
pop { work }
RET
#else /* ARM version. */
cmp r1, #0
eor ip, r0, r1 @ save the sign of the result.
beq LSYM(Ldiv0)
rsbmi r1, r1, #0 @ loops below use unsigned.
subs r2, r1, #1 @ division by 1 or -1 ?
beq 10f
movs r3, r0
rsbmi r3, r0, #0 @ positive dividend value
cmp r3, r1
bls 11f
tst r1, r2 @ divisor is power of 2 ?
beq 12f
ARM_DIV_BODY r3, r1, r0, r2
cmp ip, #0
rsbmi r0, r0, #0
RET
10: teq ip, r0 @ same sign ?
rsbmi r0, r0, #0
RET
11: movlo r0, #0
moveq r0, ip, asr #31
orreq r0, r0, #1
RET
12: ARM_DIV2_ORDER r1, r2
cmp ip, #0
mov r0, r3, lsr r2
rsbmi r0, r0, #0
RET
#endif /* ARM version */
DIV_FUNC_END divsi3
FUNC_START aeabi_idivmod
#ifdef __thumb__
push {r0, r1, lr}
bl SYM(__divsi3)
POP {r1, r2, r3}
mul r2, r0
sub r1, r1, r2
bx r3
#else
stmfd sp!, { r0, r1, lr }
bl SYM(__divsi3)
ldmfd sp!, { r1, r2, lr }
mul r3, r2, r0
sub r1, r1, r3
RET
#endif
FUNC_END aeabi_idivmod
#endif /* L_divsi3 */
/* ------------------------------------------------------------------------ */
#ifdef L_modsi3
FUNC_START modsi3
#ifdef __thumb__
mov curbit, #1
cmp divisor, #0
beq LSYM(Ldiv0)
bpl LSYM(Lover10)
neg divisor, divisor @ Loops below use unsigned.
LSYM(Lover10):
push { work }
@ Need to save the sign of the dividend, unfortunately, we need
@ work later on. Must do this after saving the original value of
@ the work register, because we will pop this value off first.
push { dividend }
cmp dividend, #0
bpl LSYM(Lover11)
neg dividend, dividend
LSYM(Lover11):
cmp dividend, divisor
blo LSYM(Lgot_result)
THUMB_DIV_MOD_BODY 1
pop { work }
cmp work, #0
bpl LSYM(Lover12)
neg dividend, dividend
LSYM(Lover12):
pop { work }
RET
#else /* ARM version. */
cmp r1, #0
beq LSYM(Ldiv0)
rsbmi r1, r1, #0 @ loops below use unsigned.
movs ip, r0 @ preserve sign of dividend
rsbmi r0, r0, #0 @ if negative make positive
subs r2, r1, #1 @ compare divisor with 1
cmpne r0, r1 @ compare dividend with divisor
moveq r0, #0
tsthi r1, r2 @ see if divisor is power of 2
andeq r0, r0, r2
bls 10f
ARM_MOD_BODY r0, r1, r2, r3
10: cmp ip, #0
rsbmi r0, r0, #0
RET
#endif /* ARM version */
DIV_FUNC_END modsi3
#endif /* L_modsi3 */
/* ------------------------------------------------------------------------ */
#ifdef L_dvmd_tls
FUNC_START div0
FUNC_ALIAS aeabi_idiv0 div0
FUNC_ALIAS aeabi_ldiv0 div0
RET
FUNC_END aeabi_ldiv0
FUNC_END aeabi_idiv0
FUNC_END div0
#endif /* L_divmodsi_tools */
/* ------------------------------------------------------------------------ */
#ifdef L_dvmd_lnx
@ GNU/Linux division-by zero handler. Used in place of L_dvmd_tls
/* Constant taken from <asm/signal.h>. */
#define SIGFPE 8
.code 32
FUNC_START div0
stmfd sp!, {r1, lr}
mov r0, #SIGFPE
bl SYM(raise) __PLT__
RETLDM r1
FUNC_END div0
#endif /* L_dvmd_lnx */
/* ------------------------------------------------------------------------ */
/* Dword shift operations. */
/* All the following Dword shift variants rely on the fact that
shft xxx, Reg
is in fact done as
shft xxx, (Reg & 255)
so for Reg value in (32...63) and (-1...-31) we will get zero (in the
case of logical shifts) or the sign (for asr). */
#ifdef __ARMEB__
#define al r1
#define ah r0
#else
#define al r0
#define ah r1
#endif
/* Prevent __aeabi double-word shifts from being produced on SymbianOS. */
#ifndef __symbian__
#ifdef L_lshrdi3
FUNC_START lshrdi3
FUNC_ALIAS aeabi_llsr lshrdi3
#ifdef __thumb__
lsr al, r2
mov r3, ah
lsr ah, r2
mov ip, r3
sub r2, #32
lsr r3, r2
orr al, r3
neg r2, r2
mov r3, ip
lsl r3, r2
orr al, r3
RET
#else
subs r3, r2, #32
rsb ip, r2, #32
movmi al, al, lsr r2
movpl al, ah, lsr r3
orrmi al, al, ah, lsl ip
mov ah, ah, lsr r2
RET
#endif
FUNC_END aeabi_llsr
FUNC_END lshrdi3
#endif
#ifdef L_ashrdi3
FUNC_START ashrdi3
FUNC_ALIAS aeabi_lasr ashrdi3
#ifdef __thumb__
lsr al, r2
mov r3, ah
asr ah, r2
sub r2, #32
@ If r2 is negative at this point the following step would OR
@ the sign bit into all of AL. That's not what we want...
bmi 1f
mov ip, r3
asr r3, r2
orr al, r3
mov r3, ip
1:
neg r2, r2
lsl r3, r2
orr al, r3
RET
#else
subs r3, r2, #32
rsb ip, r2, #32
movmi al, al, lsr r2
movpl al, ah, asr r3
orrmi al, al, ah, lsl ip
mov ah, ah, asr r2
RET
#endif
FUNC_END aeabi_lasr
FUNC_END ashrdi3
#endif
#ifdef L_ashldi3
FUNC_START ashldi3
FUNC_ALIAS aeabi_llsl ashldi3
#ifdef __thumb__
lsl ah, r2
mov r3, al
lsl al, r2
mov ip, r3
sub r2, #32
lsl r3, r2
orr ah, r3
neg r2, r2
mov r3, ip
lsr r3, r2
orr ah, r3
RET
#else
subs r3, r2, #32
rsb ip, r2, #32
movmi ah, ah, lsl r2
movpl ah, al, lsl r3
orrmi ah, ah, al, lsr ip
mov al, al, lsl r2
RET
#endif
FUNC_END aeabi_llsl
FUNC_END ashldi3
#endif
#endif /* __symbian__ */
/* ------------------------------------------------------------------------ */
/* These next two sections are here despite the fact that they contain Thumb
assembler because their presence allows interworked code to be linked even
when the GCC library is this one. */
/* Do not build the interworking functions when the target architecture does
not support Thumb instructions. (This can be a multilib option). */
#if defined __ARM_ARCH_4T__ || defined __ARM_ARCH_5T__\
|| defined __ARM_ARCH_5TE__ || defined __ARM_ARCH_5TEJ__ \
|| __ARM_ARCH__ >= 6
#if defined L_call_via_rX
/* These labels & instructions are used by the Arm/Thumb interworking code.
The address of function to be called is loaded into a register and then
one of these labels is called via a BL instruction. This puts the
return address into the link register with the bottom bit set, and the
code here switches to the correct mode before executing the function. */
.text
.align 0
.force_thumb
.macro call_via register
THUMB_FUNC_START _call_via_\register
bx \register
nop
SIZE (_call_via_\register)
.endm
call_via r0
call_via r1
call_via r2
call_via r3
call_via r4
call_via r5
call_via r6
call_via r7
call_via r8
call_via r9
call_via sl
call_via fp
call_via ip
call_via sp
call_via lr
#endif /* L_call_via_rX */
#if defined L_interwork_call_via_rX
/* These labels & instructions are used by the Arm/Thumb interworking code,
when the target address is in an unknown instruction set. The address
of function to be called is loaded into a register and then one of these
labels is called via a BL instruction. This puts the return address
into the link register with the bottom bit set, and the code here
switches to the correct mode before executing the function. Unfortunately
the target code cannot be relied upon to return via a BX instruction, so
instead we have to store the resturn address on the stack and allow the
called function to return here instead. Upon return we recover the real
return address and use a BX to get back to Thumb mode.
There are three variations of this code. The first,
_interwork_call_via_rN(), will push the return address onto the
stack and pop it in _arm_return(). It should only be used if all
arguments are passed in registers.
The second, _interwork_r7_call_via_rN(), instead stores the return
address at [r7, #-4]. It is the caller's responsibility to ensure
that this address is valid and contains no useful data.
The third, _interwork_r11_call_via_rN(), works in the same way but
uses r11 instead of r7. It is useful if the caller does not really
need a frame pointer. */
.text
.align 0
.code 32
.globl _arm_return
LSYM(Lstart_arm_return):
cfi_start LSYM(Lstart_arm_return) LSYM(Lend_arm_return)
cfi_push 0, 0xe, -0x8, 0x8
nop @ This nop is for the benefit of debuggers, so that
@ backtraces will use the correct unwind information.
_arm_return:
RETLDM unwind=LSYM(Lstart_arm_return)
cfi_end LSYM(Lend_arm_return)
.globl _arm_return_r7
_arm_return_r7:
ldr lr, [r7, #-4]
bx lr
.globl _arm_return_r11
_arm_return_r11:
ldr lr, [r11, #-4]
bx lr
.macro interwork_with_frame frame, register, name, return
.code 16
THUMB_FUNC_START \name
bx pc
nop
.code 32
tst \register, #1
streq lr, [\frame, #-4]
adreq lr, _arm_return_\frame
bx \register
SIZE (\name)
.endm
.macro interwork register
.code 16
THUMB_FUNC_START _interwork_call_via_\register
bx pc
nop
.code 32
.globl LSYM(Lchange_\register)
LSYM(Lchange_\register):
tst \register, #1
streq lr, [sp, #-8]!
adreq lr, _arm_return
bx \register
SIZE (_interwork_call_via_\register)
interwork_with_frame r7,\register,_interwork_r7_call_via_\register
interwork_with_frame r11,\register,_interwork_r11_call_via_\register
.endm
interwork r0
interwork r1
interwork r2
interwork r3
interwork r4
interwork r5
interwork r6
interwork r7
interwork r8
interwork r9
interwork sl
interwork fp
interwork ip
interwork sp
/* The LR case has to be handled a little differently... */
.code 16
THUMB_FUNC_START _interwork_call_via_lr
bx pc
nop
.code 32
.globl .Lchange_lr
.Lchange_lr:
tst lr, #1
stmeqdb r13!, {lr, pc}
mov ip, lr
adreq lr, _arm_return
bx ip
SIZE (_interwork_call_via_lr)
#endif /* L_interwork_call_via_rX */
#endif /* Arch supports thumb. */
#ifndef __symbian__
#include "ieee754-df.S"
#include "ieee754-sf.S"
#include "bpabi.S"
#endif /* __symbian__ */
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