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gcc/libgcc/config/arm/lib1funcs.S
Jakub Jelinek a554497024 Update copyright years. 
From-SVN: r267494
2019-01-01 13:31:55 +01:00

2174 lines
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ArmAsm
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@ libgcc routines for ARM cpu.
@ Division routines, written by Richard Earnshaw, (rearnsha@armltd.co.uk)
/* Copyright (C) 1995-2019 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 3, or (at your option) any
later version.
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.
Under Section 7 of GPL version 3, you are granted additional
permissions described in the GCC Runtime Library Exception, version
3.1, as published by the Free Software Foundation.
You should have received a copy of the GNU General Public License and
a copy of the GCC Runtime Library Exception along with this program;
see the files COPYING3 and COPYING.RUNTIME respectively. If not, see
<http://www.gnu.org/licenses/>. */
/* An executable stack is *not* required for these functions. */
#if defined(__ELF__) && defined(__linux__)
.section .note.GNU-stack,"",%progbits
.previous
#endif /* __ELF__ and __linux__ */
#ifdef __ARM_EABI__
/* Some attributes that are common to all routines in this file. */
/* Tag_ABI_align_needed: This code does not require 8-byte
alignment from the caller. */
/* .eabi_attribute 24, 0 -- default setting. */
/* Tag_ABI_align_preserved: This code preserves 8-byte
alignment in any callee. */
.eabi_attribute 25, 1
#endif /* __ARM_EABI__ */
/* ------------------------------------------------------------------------ */
/* 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). */
#elif defined __vxworks && !defined __PIC__
#define __PLT__ /* Not supported by the kernel loader. */
#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. */
/* There are times when we might prefer Thumb1 code even if ARM code is
permitted, for example, the code might be smaller, or there might be
interworking problems with switching to ARM state if interworking is
disabled. */
#if (defined(__thumb__) \
&& !defined(__thumb2__) \
&& (!defined(__THUMB_INTERWORK__) \
|| defined (__OPTIMIZE_SIZE__) \
|| !__ARM_ARCH_ISA_ARM))
# define __prefer_thumb__
#endif
#if !__ARM_ARCH_ISA_ARM && __ARM_ARCH_ISA_THUMB == 1
#define NOT_ISA_TARGET_32BIT 1
#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
# if defined(__thumb2__)
pop\cond {\regs, lr}
# else
ldm\cond\dirn sp!, {\regs, lr}
# endif
.endif
.ifnc "\unwind", ""
/* Mark LR as restored. */
97: cfi_pop 97b - \unwind, 0xe, 0x0
.endif
bx\cond lr
#else
/* Caller is responsible for providing IT instruction. */
.ifc "\regs",""
ldr\cond pc, [sp], #8
.else
# if defined(__thumb2__)
pop\cond {\regs, pc}
# else
ldm\cond\dirn sp!, {\regs, pc}
# endif
.endif
#endif
.endm
/* The Unified assembly syntax allows the same code to be assembled for both
ARM and Thumb-2. However this is only supported by recent gas, so define
a set of macros to allow ARM code on older assemblers. */
#if defined(__thumb2__)
.macro do_it cond, suffix=""
it\suffix \cond
.endm
.macro shift1 op, arg0, arg1, arg2
\op \arg0, \arg1, \arg2
.endm
#define do_push push
#define do_pop pop
#define COND(op1, op2, cond) op1 ## op2 ## cond
/* Perform an arithmetic operation with a variable shift operand. This
requires two instructions and a scratch register on Thumb-2. */
.macro shiftop name, dest, src1, src2, shiftop, shiftreg, tmp
\shiftop \tmp, \src2, \shiftreg
\name \dest, \src1, \tmp
.endm
#else
.macro do_it cond, suffix=""
.endm
.macro shift1 op, arg0, arg1, arg2
mov \arg0, \arg1, \op \arg2
.endm
#define do_push stmfd sp!,
#define do_pop ldmfd sp!,
#define COND(op1, op2, cond) op1 ## cond ## op2
.macro shiftop name, dest, src1, src2, shiftop, shiftreg, tmp
\name \dest, \src1, \src2, \shiftop \shiftreg
.endm
#endif
#ifdef __ARM_EABI__
.macro ARM_LDIV0 name signed
cmp r0, #0
.ifc \signed, unsigned
movne r0, #0xffffffff
.else
movgt r0, #0x7fffffff
movlt r0, #0x80000000
.endif
b SYM (__aeabi_idiv0) __PLT__
.endm
#else
.macro ARM_LDIV0 name signed
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
#endif
#ifdef __ARM_EABI__
.macro THUMB_LDIV0 name signed
#ifdef NOT_ISA_TARGET_32BIT
push {r0, lr}
mov r0, #0
bl SYM(__aeabi_idiv0)
@ We know we are not on armv4t, so pop pc is safe.
pop {r1, pc}
#elif defined(__thumb2__)
.syntax unified
.ifc \signed, unsigned
cbz r0, 1f
mov r0, #0xffffffff
1:
.else
cmp r0, #0
do_it gt
movgt r0, #0x7fffffff
do_it lt
movlt r0, #0x80000000
.endif
b.w SYM(__aeabi_idiv0) __PLT__
#else
.align 2
bx pc
nop
.arm
cmp r0, #0
.ifc \signed, unsigned
movne r0, #0xffffffff
.else
movgt r0, #0x7fffffff
movlt r0, #0x80000000
.endif
b SYM(__aeabi_idiv0) __PLT__
.thumb
#endif
.endm
#else
.macro THUMB_LDIV0 name signed
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
#endif
.macro FUNC_END name
SIZE (__\name)
.endm
.macro DIV_FUNC_END name signed
cfi_start __\name, LSYM(Lend_div0)
LSYM(Ldiv0):
#ifdef __thumb__
THUMB_LDIV0 \name \signed
#else
ARM_LDIV0 \name \signed
#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
# if defined(__thumb2__)
#define THUMB_SYNTAX .syntax divided
# else
#define THUMB_SYNTAX
# endif
#else
#define THUMB_FUNC
#define THUMB_CODE
#define THUMB_SYNTAX
#endif
.macro FUNC_START name
.text
.globl SYM (__\name)
TYPE (__\name)
.align 0
THUMB_CODE
THUMB_FUNC
THUMB_SYNTAX
SYM (__\name):
.endm
.macro ARM_SYM_START name
TYPE (\name)
.align 0
SYM (\name):
.endm
.macro SYM_END name
SIZE (\name)
.endm
/* Special function that will always be coded in ARM assembly, even if
in Thumb-only compilation. */
#if defined(__thumb2__)
/* For Thumb-2 we build everything in thumb mode. */
.macro ARM_FUNC_START name
FUNC_START \name
.syntax unified
.endm
#define EQUIV .thumb_set
.macro ARM_CALL name
bl __\name
.endm
#elif 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 /* !(__INTERWORKING_STUBS__ || __thumb2__) */
#ifdef NOT_ISA_TARGET_32BIT
#define EQUIV .thumb_set
#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
#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
#ifndef NOT_ISA_TARGET_32BIT
.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
#endif
#ifdef __ARMEB__
#define xxh r0
#define xxl r1
#define yyh r2
#define yyl r3
#else
#define xxh r1
#define xxl r0
#define yyh r3
#define yyl r2
#endif
#ifdef __ARM_EABI__
.macro WEAK name
.weak SYM (__\name)
.endm
#endif
#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 defined (__ARM_FEATURE_CLZ) && ! defined (__OPTIMIZE_SIZE__)
#if defined (__thumb2__)
clz \curbit, \dividend
clz \result, \divisor
sub \curbit, \result, \curbit
rsb \curbit, \curbit, #31
adr \result, 1f
add \curbit, \result, \curbit, lsl #4
mov \result, #0
mov pc, \curbit
.p2align 3
1:
.set shift, 32
.rept 32
.set shift, shift - 1
cmp.w \dividend, \divisor, lsl #shift
nop.n
adc.w \result, \result, \result
it cs
subcs.w \dividend, \dividend, \divisor, lsl #shift
.endr
#else
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
#endif
#else /* !defined (__ARM_FEATURE_CLZ) || defined (__OPTIMIZE_SIZE__) */
#if defined (__ARM_FEATURE_CLZ)
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 /* !defined (__ARM_FEATURE_CLZ) */
@ 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 /* !defined (__ARM_FEATURE_CLZ) */
@ Division loop
1: cmp \dividend, \divisor
do_it hs, t
subhs \dividend, \dividend, \divisor
orrhs \result, \result, \curbit
cmp \dividend, \divisor, lsr #1
do_it hs, t
subhs \dividend, \dividend, \divisor, lsr #1
orrhs \result, \result, \curbit, lsr #1
cmp \dividend, \divisor, lsr #2
do_it hs, t
subhs \dividend, \dividend, \divisor, lsr #2
orrhs \result, \result, \curbit, lsr #2
cmp \dividend, \divisor, lsr #3
do_it hs, t
subhs \dividend, \dividend, \divisor, lsr #3
orrhs \result, \result, \curbit, lsr #3
cmp \dividend, #0 @ Early termination?
do_it ne, t
movnes \curbit, \curbit, lsr #4 @ No, any more bits to do?
movne \divisor, \divisor, lsr #4
bne 1b
#endif /* !defined (__ARM_FEATURE_CLZ) || defined (__OPTIMIZE_SIZE__) */
.endm
/* ------------------------------------------------------------------------ */
.macro ARM_DIV2_ORDER divisor, order
#if defined (__ARM_FEATURE_CLZ)
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 defined(__ARM_FEATURE_CLZ) && ! 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 /* !defined (__ARM_FEATURE_CLZ) || defined (__OPTIMIZE_SIZE__) */
#if defined (__ARM_FEATURE_CLZ)
clz \order, \divisor
clz \spare, \dividend
sub \order, \order, \spare
mov \divisor, \divisor, lsl \order
#else /* !defined (__ARM_FEATURE_CLZ) */
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 /* !defined (__ARM_FEATURE_CLZ) */
@ 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 /* !defined (__ARM_FEATURE_CLZ) || 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
/* If performance is preferred, the following functions are provided. */
#if defined(__prefer_thumb__) && !defined(__OPTIMIZE_SIZE__)
/* Branch to div(n), and jump to label if curbit is lo than divisior. */
.macro BranchToDiv n, label
lsr curbit, dividend, \n
cmp curbit, divisor
blo \label
.endm
/* Body of div(n). Shift the divisor in n bits and compare the divisor
and dividend. Update the dividend as the substruction result. */
.macro DoDiv n
lsr curbit, dividend, \n
cmp curbit, divisor
bcc 1f
lsl curbit, divisor, \n
sub dividend, dividend, curbit
1: adc result, result
.endm
/* The body of division with positive divisor. 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. */
.macro THUMB1_Div_Positive
mov result, #0
BranchToDiv #1, LSYM(Lthumb1_div1)
BranchToDiv #4, LSYM(Lthumb1_div4)
BranchToDiv #8, LSYM(Lthumb1_div8)
BranchToDiv #12, LSYM(Lthumb1_div12)
BranchToDiv #16, LSYM(Lthumb1_div16)
LSYM(Lthumb1_div_large_positive):
mov result, #0xff
lsl divisor, divisor, #8
rev result, result
lsr curbit, dividend, #16
cmp curbit, divisor
blo 1f
asr result, #8
lsl divisor, divisor, #8
beq LSYM(Ldivbyzero_waypoint)
1: lsr curbit, dividend, #12
cmp curbit, divisor
blo LSYM(Lthumb1_div12)
b LSYM(Lthumb1_div16)
LSYM(Lthumb1_div_loop):
lsr divisor, divisor, #8
LSYM(Lthumb1_div16):
Dodiv #15
Dodiv #14
Dodiv #13
Dodiv #12
LSYM(Lthumb1_div12):
Dodiv #11
Dodiv #10
Dodiv #9
Dodiv #8
bcs LSYM(Lthumb1_div_loop)
LSYM(Lthumb1_div8):
Dodiv #7
Dodiv #6
Dodiv #5
LSYM(Lthumb1_div5):
Dodiv #4
LSYM(Lthumb1_div4):
Dodiv #3
LSYM(Lthumb1_div3):
Dodiv #2
LSYM(Lthumb1_div2):
Dodiv #1
LSYM(Lthumb1_div1):
sub divisor, dividend, divisor
bcs 1f
cpy divisor, dividend
1: adc result, result
cpy dividend, result
RET
LSYM(Ldivbyzero_waypoint):
b LSYM(Ldiv0)
.endm
/* The body of division with negative divisor. Similar with
THUMB1_Div_Positive except that the shift steps are in multiples
of six bits. */
.macro THUMB1_Div_Negative
lsr result, divisor, #31
beq 1f
neg divisor, divisor
1: asr curbit, dividend, #32
bcc 2f
neg dividend, dividend
2: eor curbit, result
mov result, #0
cpy ip, curbit
BranchToDiv #4, LSYM(Lthumb1_div_negative4)
BranchToDiv #8, LSYM(Lthumb1_div_negative8)
LSYM(Lthumb1_div_large):
mov result, #0xfc
lsl divisor, divisor, #6
rev result, result
lsr curbit, dividend, #8
cmp curbit, divisor
blo LSYM(Lthumb1_div_negative8)
lsl divisor, divisor, #6
asr result, result, #6
cmp curbit, divisor
blo LSYM(Lthumb1_div_negative8)
lsl divisor, divisor, #6
asr result, result, #6
cmp curbit, divisor
blo LSYM(Lthumb1_div_negative8)
lsl divisor, divisor, #6
beq LSYM(Ldivbyzero_negative)
asr result, result, #6
b LSYM(Lthumb1_div_negative8)
LSYM(Lthumb1_div_negative_loop):
lsr divisor, divisor, #6
LSYM(Lthumb1_div_negative8):
DoDiv #7
DoDiv #6
DoDiv #5
DoDiv #4
LSYM(Lthumb1_div_negative4):
DoDiv #3
DoDiv #2
bcs LSYM(Lthumb1_div_negative_loop)
DoDiv #1
sub divisor, dividend, divisor
bcs 1f
cpy divisor, dividend
1: cpy curbit, ip
adc result, result
asr curbit, curbit, #1
cpy dividend, result
bcc 2f
neg dividend, dividend
cmp curbit, #0
2: bpl 3f
neg divisor, divisor
3: RET
LSYM(Ldivbyzero_negative):
cpy curbit, ip
asr curbit, curbit, #1
bcc LSYM(Ldiv0)
neg dividend, dividend
.endm
#endif /* ARM Thumb version. */
/* ------------------------------------------------------------------------ */
/* Start of the Real Functions */
/* ------------------------------------------------------------------------ */
#ifdef L_udivsi3
#if defined(__prefer_thumb__)
FUNC_START udivsi3
FUNC_ALIAS aeabi_uidiv udivsi3
#if defined(__OPTIMIZE_SIZE__)
cmp divisor, #0
beq LSYM(Ldiv0)
LSYM(udivsi3_skip_div0_test):
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
/* Implementation of aeabi_uidiv for ARMv6m. This version is only
used in ARMv6-M when we need an efficient implementation. */
#else
LSYM(udivsi3_skip_div0_test):
THUMB1_Div_Positive
#endif /* __OPTIMIZE_SIZE__ */
#elif defined(__ARM_ARCH_EXT_IDIV__)
ARM_FUNC_START udivsi3
ARM_FUNC_ALIAS aeabi_uidiv udivsi3
cmp r1, #0
beq LSYM(Ldiv0)
udiv r0, r0, r1
RET
#else /* ARM version/Thumb-2. */
ARM_FUNC_START udivsi3
ARM_FUNC_ALIAS aeabi_uidiv udivsi3
/* Note: if called via udivsi3_skip_div0_test, this will unnecessarily
check for division-by-zero a second time. */
LSYM(udivsi3_skip_div0_test):
subs r2, r1, #1
do_it eq
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: do_it eq, e
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 unsigned
#if defined(__prefer_thumb__)
FUNC_START aeabi_uidivmod
cmp r1, #0
beq LSYM(Ldiv0)
# if defined(__OPTIMIZE_SIZE__)
push {r0, r1, lr}
bl LSYM(udivsi3_skip_div0_test)
POP {r1, r2, r3}
mul r2, r0
sub r1, r1, r2
bx r3
# else
/* Both the quotient and remainder are calculated simultaneously
in THUMB1_Div_Positive. There is no need to calculate the
remainder again here. */
b LSYM(udivsi3_skip_div0_test)
RET
# endif /* __OPTIMIZE_SIZE__ */
#elif defined(__ARM_ARCH_EXT_IDIV__)
ARM_FUNC_START aeabi_uidivmod
cmp r1, #0
beq LSYM(Ldiv0)
mov r2, r0
udiv r0, r0, r1
mls r1, r0, r1, r2
RET
#else
ARM_FUNC_START aeabi_uidivmod
cmp r1, #0
beq LSYM(Ldiv0)
stmfd sp!, { r0, r1, lr }
bl LSYM(udivsi3_skip_div0_test)
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
#if defined(__ARM_ARCH_EXT_IDIV__) && __ARM_ARCH_ISA_THUMB != 1
ARM_FUNC_START umodsi3
cmp r1, #0
beq LSYM(Ldiv0)
udiv r2, r0, r1
mls r0, r1, r2, r0
RET
#elif defined(__thumb__)
FUNC_START umodsi3
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. */
FUNC_START umodsi3
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 unsigned
#endif /* L_umodsi3 */
/* ------------------------------------------------------------------------ */
#ifdef L_divsi3
#if defined(__prefer_thumb__)
FUNC_START divsi3
FUNC_ALIAS aeabi_idiv divsi3
#if defined(__OPTIMIZE_SIZE__)
cmp divisor, #0
beq LSYM(Ldiv0)
LSYM(divsi3_skip_div0_test):
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
/* Implementation of aeabi_idiv for ARMv6m. This version is only
used in ARMv6-M when we need an efficient implementation. */
#else
LSYM(divsi3_skip_div0_test):
cpy curbit, dividend
orr curbit, divisor
bmi LSYM(Lthumb1_div_negative)
LSYM(Lthumb1_div_positive):
THUMB1_Div_Positive
LSYM(Lthumb1_div_negative):
THUMB1_Div_Negative
#endif /* __OPTIMIZE_SIZE__ */
#elif defined(__ARM_ARCH_EXT_IDIV__)
ARM_FUNC_START divsi3
ARM_FUNC_ALIAS aeabi_idiv divsi3
cmp r1, #0
beq LSYM(Ldiv0)
sdiv r0, r0, r1
RET
#else /* ARM/Thumb-2 version. */
ARM_FUNC_START divsi3
ARM_FUNC_ALIAS aeabi_idiv divsi3
cmp r1, #0
beq LSYM(Ldiv0)
LSYM(divsi3_skip_div0_test):
eor ip, r0, r1 @ save the sign of the result.
do_it mi
rsbmi r1, r1, #0 @ loops below use unsigned.
subs r2, r1, #1 @ division by 1 or -1 ?
beq 10f
movs r3, r0
do_it mi
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
do_it mi
rsbmi r0, r0, #0
RET
10: teq ip, r0 @ same sign ?
do_it mi
rsbmi r0, r0, #0
RET
11: do_it lo
movlo r0, #0
do_it eq,t
moveq r0, ip, asr #31
orreq r0, r0, #1
RET
12: ARM_DIV2_ORDER r1, r2
cmp ip, #0
mov r0, r3, lsr r2
do_it mi
rsbmi r0, r0, #0
RET
#endif /* ARM version */
DIV_FUNC_END divsi3 signed
#if defined(__prefer_thumb__)
FUNC_START aeabi_idivmod
cmp r1, #0
beq LSYM(Ldiv0)
# if defined(__OPTIMIZE_SIZE__)
push {r0, r1, lr}
bl LSYM(divsi3_skip_div0_test)
POP {r1, r2, r3}
mul r2, r0
sub r1, r1, r2
bx r3
# else
/* Both the quotient and remainder are calculated simultaneously
in THUMB1_Div_Positive and THUMB1_Div_Negative. There is no
need to calculate the remainder again here. */
b LSYM(divsi3_skip_div0_test)
RET
# endif /* __OPTIMIZE_SIZE__ */
#elif defined(__ARM_ARCH_EXT_IDIV__)
ARM_FUNC_START aeabi_idivmod
cmp r1, #0
beq LSYM(Ldiv0)
mov r2, r0
sdiv r0, r0, r1
mls r1, r0, r1, r2
RET
#else
ARM_FUNC_START aeabi_idivmod
cmp r1, #0
beq LSYM(Ldiv0)
stmfd sp!, { r0, r1, lr }
bl LSYM(divsi3_skip_div0_test)
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
#if defined(__ARM_ARCH_EXT_IDIV__) && __ARM_ARCH_ISA_THUMB != 1
ARM_FUNC_START modsi3
cmp r1, #0
beq LSYM(Ldiv0)
sdiv r2, r0, r1
mls r0, r1, r2, r0
RET
#elif defined(__thumb__)
FUNC_START modsi3
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. */
FUNC_START modsi3
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 signed
#endif /* L_modsi3 */
/* ------------------------------------------------------------------------ */
#ifdef L_dvmd_tls
#ifdef __ARM_EABI__
WEAK aeabi_idiv0
WEAK aeabi_ldiv0
FUNC_START aeabi_idiv0
FUNC_START aeabi_ldiv0
RET
FUNC_END aeabi_ldiv0
FUNC_END aeabi_idiv0
#else
FUNC_START div0
RET
FUNC_END div0
#endif
#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
#ifdef __ARM_EABI__
cfi_start __aeabi_ldiv0, LSYM(Lend_aeabi_ldiv0)
WEAK aeabi_idiv0
WEAK aeabi_ldiv0
ARM_FUNC_START aeabi_idiv0
ARM_FUNC_START aeabi_ldiv0
do_push {r1, lr}
98: cfi_push 98b - __aeabi_ldiv0, 0xe, -0x4, 0x8
#else
cfi_start __div0, LSYM(Lend_div0)
ARM_FUNC_START div0
do_push {r1, lr}
98: cfi_push 98b - __div0, 0xe, -0x4, 0x8
#endif
mov r0, #SIGFPE
bl SYM(raise) __PLT__
RETLDM r1 unwind=98b
#ifdef __ARM_EABI__
cfi_end LSYM(Lend_aeabi_ldiv0)
FUNC_END aeabi_ldiv0
FUNC_END aeabi_idiv0
#else
cfi_end LSYM(Lend_div0)
FUNC_END div0
#endif
#endif /* L_dvmd_lnx */
#ifdef L_clear_cache
#if defined __ARM_EABI__ && defined __linux__
@ EABI GNU/Linux call to cacheflush syscall.
ARM_FUNC_START clear_cache
do_push {r7}
#if __ARM_ARCH >= 7 || defined(__ARM_ARCH_6T2__)
movw r7, #2
movt r7, #0xf
#else
mov r7, #0xf0000
add r7, r7, #2
#endif
mov r2, #0
swi 0
do_pop {r7}
RET
FUNC_END clear_cache
#else
#error "This is only for ARM EABI GNU/Linux"
#endif
#endif /* L_clear_cache */
#ifdef L_speculation_barrier
FUNC_START speculation_barrier
#if __ARM_ARCH >= 7
isb
dsb sy
#elif defined __ARM_EABI__ && defined __linux__
/* We don't have a speculation barrier directly for this
platform/architecture variant. But we can use a kernel
clear_cache service routine which will emit such instructions
if run on a later version of the architecture. We don't
really want to flush the cache, but we must give it a valid
address, so just clear pc..pc+1. */
#if defined __thumb__ && !defined __thumb2__
push {r7}
mov r7, #0xf
lsl r7, #16
add r7, #2
adr r0, . + 4
add r1, r0, #1
mov r2, #0
svc 0
pop {r7}
#else
do_push {r7}
#ifdef __ARM_ARCH_6T2__
movw r7, #2
movt r7, #0xf
#else
mov r7, #0xf0000
add r7, r7, #2
#endif
add r0, pc, #0 /* ADR. */
add r1, r0, #1
mov r2, #0
svc 0
do_pop {r7}
#endif /* Thumb1 only */
#else
#warning "No speculation barrier defined for this platform"
#endif
RET
FUNC_END speculation_barrier
#endif
/* ------------------------------------------------------------------------ */
/* 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__ */
#ifdef L_clzsi2
#ifdef NOT_ISA_TARGET_32BIT
FUNC_START clzsi2
mov r1, #28
mov r3, #1
lsl r3, r3, #16
cmp r0, r3 /* 0x10000 */
bcc 2f
lsr r0, r0, #16
sub r1, r1, #16
2: lsr r3, r3, #8
cmp r0, r3 /* #0x100 */
bcc 2f
lsr r0, r0, #8
sub r1, r1, #8
2: lsr r3, r3, #4
cmp r0, r3 /* #0x10 */
bcc 2f
lsr r0, r0, #4
sub r1, r1, #4
2: adr r2, 1f
ldrb r0, [r2, r0]
add r0, r0, r1
bx lr
.align 2
1:
.byte 4, 3, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0
FUNC_END clzsi2
#else
ARM_FUNC_START clzsi2
# if defined (__ARM_FEATURE_CLZ)
clz r0, r0
RET
# else
mov r1, #28
cmp r0, #0x10000
do_it cs, t
movcs r0, r0, lsr #16
subcs r1, r1, #16
cmp r0, #0x100
do_it cs, t
movcs r0, r0, lsr #8
subcs r1, r1, #8
cmp r0, #0x10
do_it cs, t
movcs r0, r0, lsr #4
subcs r1, r1, #4
adr r2, 1f
ldrb r0, [r2, r0]
add r0, r0, r1
RET
.align 2
1:
.byte 4, 3, 2, 2, 1, 1, 1, 1, 0, 0, 0, 0, 0, 0, 0, 0
# endif /* !defined (__ARM_FEATURE_CLZ) */
FUNC_END clzsi2
#endif
#endif /* L_clzsi2 */
#ifdef L_clzdi2
#if !defined (__ARM_FEATURE_CLZ)
# ifdef NOT_ISA_TARGET_32BIT
FUNC_START clzdi2
push {r4, lr}
# else
ARM_FUNC_START clzdi2
do_push {r4, lr}
# endif
cmp xxh, #0
bne 1f
# ifdef __ARMEB__
mov r0, xxl
bl __clzsi2
add r0, r0, #32
b 2f
1:
bl __clzsi2
# else
bl __clzsi2
add r0, r0, #32
b 2f
1:
mov r0, xxh
bl __clzsi2
# endif
2:
# ifdef NOT_ISA_TARGET_32BIT
pop {r4, pc}
# else
RETLDM r4
# endif
FUNC_END clzdi2
#else /* defined (__ARM_FEATURE_CLZ) */
ARM_FUNC_START clzdi2
cmp xxh, #0
do_it eq, et
clzeq r0, xxl
clzne r0, xxh
addeq r0, r0, #32
RET
FUNC_END clzdi2
#endif
#endif /* L_clzdi2 */
#ifdef L_ctzsi2
#ifdef NOT_ISA_TARGET_32BIT
FUNC_START ctzsi2
neg r1, r0
and r0, r0, r1
mov r1, #28
mov r3, #1
lsl r3, r3, #16
cmp r0, r3 /* 0x10000 */
bcc 2f
lsr r0, r0, #16
sub r1, r1, #16
2: lsr r3, r3, #8
cmp r0, r3 /* #0x100 */
bcc 2f
lsr r0, r0, #8
sub r1, r1, #8
2: lsr r3, r3, #4
cmp r0, r3 /* #0x10 */
bcc 2f
lsr r0, r0, #4
sub r1, r1, #4
2: adr r2, 1f
ldrb r0, [r2, r0]
sub r0, r0, r1
bx lr
.align 2
1:
.byte 27, 28, 29, 29, 30, 30, 30, 30, 31, 31, 31, 31, 31, 31, 31, 31
FUNC_END ctzsi2
#else
ARM_FUNC_START ctzsi2
rsb r1, r0, #0
and r0, r0, r1
# if defined (__ARM_FEATURE_CLZ)
clz r0, r0
rsb r0, r0, #31
RET
# else
mov r1, #28
cmp r0, #0x10000
do_it cs, t
movcs r0, r0, lsr #16
subcs r1, r1, #16
cmp r0, #0x100
do_it cs, t
movcs r0, r0, lsr #8
subcs r1, r1, #8
cmp r0, #0x10
do_it cs, t
movcs r0, r0, lsr #4
subcs r1, r1, #4
adr r2, 1f
ldrb r0, [r2, r0]
sub r0, r0, r1
RET
.align 2
1:
.byte 27, 28, 29, 29, 30, 30, 30, 30, 31, 31, 31, 31, 31, 31, 31, 31
# endif /* !defined (__ARM_FEATURE_CLZ) */
FUNC_END ctzsi2
#endif
#endif /* L_clzsi2 */
/* ------------------------------------------------------------------------ */
/* 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 */
/* Don't bother with the old interworking routines for Thumb-2. */
/* ??? Maybe only omit these on "m" variants. */
#if !defined(__thumb2__) && __ARM_ARCH_ISA_ARM
#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 /* !__thumb2__ */
/* Functions to support compact pic switch tables in thumb1 state.
All these routines take an index into the table in r0. The
table is at LR & ~1 (but this must be rounded up in the case
of 32-bit entires). They are only permitted to clobber r12
and r14 and r0 must be preserved on exit. */
#ifdef L_thumb1_case_sqi
.text
.align 0
.force_thumb
.syntax unified
THUMB_FUNC_START __gnu_thumb1_case_sqi
push {r1}
mov r1, lr
lsrs r1, r1, #1
lsls r1, r1, #1
ldrsb r1, [r1, r0]
lsls r1, r1, #1
add lr, lr, r1
pop {r1}
bx lr
SIZE (__gnu_thumb1_case_sqi)
#endif
#ifdef L_thumb1_case_uqi
.text
.align 0
.force_thumb
.syntax unified
THUMB_FUNC_START __gnu_thumb1_case_uqi
push {r1}
mov r1, lr
lsrs r1, r1, #1
lsls r1, r1, #1
ldrb r1, [r1, r0]
lsls r1, r1, #1
add lr, lr, r1
pop {r1}
bx lr
SIZE (__gnu_thumb1_case_uqi)
#endif
#ifdef L_thumb1_case_shi
.text
.align 0
.force_thumb
.syntax unified
THUMB_FUNC_START __gnu_thumb1_case_shi
push {r0, r1}
mov r1, lr
lsrs r1, r1, #1
lsls r0, r0, #1
lsls r1, r1, #1
ldrsh r1, [r1, r0]
lsls r1, r1, #1
add lr, lr, r1
pop {r0, r1}
bx lr
SIZE (__gnu_thumb1_case_shi)
#endif
#ifdef L_thumb1_case_uhi
.text
.align 0
.force_thumb
.syntax unified
THUMB_FUNC_START __gnu_thumb1_case_uhi
push {r0, r1}
mov r1, lr
lsrs r1, r1, #1
lsls r0, r0, #1
lsls r1, r1, #1
ldrh r1, [r1, r0]
lsls r1, r1, #1
add lr, lr, r1
pop {r0, r1}
bx lr
SIZE (__gnu_thumb1_case_uhi)
#endif
#ifdef L_thumb1_case_si
.text
.align 0
.force_thumb
.syntax unified
THUMB_FUNC_START __gnu_thumb1_case_si
push {r0, r1}
mov r1, lr
adds.n r1, r1, #2 /* Align to word. */
lsrs r1, r1, #2
lsls r0, r0, #2
lsls r1, r1, #2
ldr r0, [r1, r0]
adds r0, r0, r1
mov lr, r0
pop {r0, r1}
mov pc, lr /* We know we were called from thumb code. */
SIZE (__gnu_thumb1_case_si)
#endif
#endif /* Arch supports thumb. */
.macro CFI_START_FUNCTION
.cfi_startproc
.cfi_remember_state
.endm
.macro CFI_END_FUNCTION
.cfi_restore_state
.cfi_endproc
.endm
#ifndef __symbian__
/* The condition here must match the one in gcc/config/arm/elf.h and
libgcc/config/arm/t-elf. */
#ifndef NOT_ISA_TARGET_32BIT
#include "ieee754-df.S"
#include "ieee754-sf.S"
#include "bpabi.S"
#else /* NOT_ISA_TARGET_32BIT */
#include "bpabi-v6m.S"
#endif /* NOT_ISA_TARGET_32BIT */
#endif /* !__symbian__ */
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