Commit c5a543ea authored by Marek Vasut's avatar Marek Vasut Committed by Tom Rini

arm: lib: Sync libgcc 32b division/modulo operations

Sync the libgcc 32bit division and modulo operations with Linux 4.4.6 ,
commit 0d1912303e54ed1b2a371be0bba51c384dd57326 . The functions in these
four files are present in lib1funcs.S in Linux, so replace these files
with lib1funcs.S from Linux.

Since we do not support stack unwinding, instead of importing the whole
asm/unwind.h and all the baggage, this patch defines empty UNWIND() macro
in lib1funcs.S . Moreover, to make all of the functions available, define
CONFIG_AEABI , which is safe, because U-Boot is always compiled with ARM
EABI.

This patch also defines CONFIG_THUMB2_KERNEL and CONFIG_ARM_ASM_UNIFIED
which is necessary for correct build of these files both in ARM and
Thumb mode, just like Linux does.
Signed-off-by: default avatarMarek Vasut <marex@denx.de>
Cc: Albert Aribaud <albert.u.boot@aribaud.net>
Cc: Masahiro Yamada <yamada.masahiro@socionext.com>
Cc: Simon Glass <sjg@chromium.org>
Cc: Tom Rini <trini@konsulko.com>
Reviewed-by: default avatarTom Rini <trini@konsulko.com>
parent 06b36cb7
......@@ -5,9 +5,8 @@
# SPDX-License-Identifier: GPL-2.0+
#
lib-$(CONFIG_USE_PRIVATE_LIBGCC) += ashldi3.o ashrdi3.o divsi3.o \
lshrdi3.o modsi3.o udivsi3.o umodsi3.o div0.o \
uldivmod.o
lib-$(CONFIG_USE_PRIVATE_LIBGCC) += ashldi3.o ashrdi3.o lshrdi3.o \
lib1funcs.o uldivmod.o div0.o
ifdef CONFIG_CPU_V7M
obj-y += vectors_m.o crt0.o
......
/*
* linux/arch/arm/lib/lib1funcs.S: Optimized ARM division routines
*
* Author: Nicolas Pitre <nico@fluxnic.net>
* - contributed to gcc-3.4 on Sep 30, 2003
* - adapted for the Linux kernel on Oct 2, 2003
*/
/* Copyright 1995, 1996, 1998, 1999, 2000, 2003 Free Software Foundation, Inc.
* SPDX-License-Identifier: GPL-2.0+
*/
#include <linux/linkage.h>
#include <asm/assembler.h>
/*
* U-Boot compatibility bit, define empty UNWIND() macro as, since we
* do not support stack unwinding and define CONFIG_AEABI to make all
* of the functions available without diverging from Linux code.
*/
#ifdef __UBOOT__
#define UNWIND(x...)
#define CONFIG_AEABI
#endif
.macro ARM_DIV_BODY dividend, divisor, result, curbit
......@@ -11,7 +36,7 @@
mov \divisor, \divisor, lsl \result
mov \curbit, \curbit, lsl \result
mov \result, #0
#else
@ Initially shift the divisor left 3 bits if possible,
......@@ -25,7 +50,7 @@
@ 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
@ division loop. Continue shifting until the divisor is
@ larger than the dividend.
1: cmp \divisor, #0x10000000
cmplo \divisor, \dividend
......@@ -65,6 +90,7 @@
.endm
.macro ARM_DIV2_ORDER divisor, order
#if __LINUX_ARM_ARCH__ >= 5
......@@ -95,10 +121,130 @@
.endm
.align 5
.globl __divsi3
__divsi3:
.macro ARM_MOD_BODY dividend, divisor, order, spare
#if __LINUX_ARM_ARCH__ >= 5
clz \order, \divisor
clz \spare, \dividend
sub \order, \order, \spare
mov \divisor, \divisor, lsl \order
#else
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
@ Perform all needed subtractions 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/subtractions 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:
.endm
ENTRY(__udivsi3)
ENTRY(__aeabi_uidiv)
UNWIND(.fnstart)
subs r2, r1, #1
reteq lr
bcc Ldiv0
cmp r0, r1
bls 11f
tst r1, r2
beq 12f
ARM_DIV_BODY r0, r1, r2, r3
mov r0, r2
ret lr
11: moveq r0, #1
movne r0, #0
ret lr
12: ARM_DIV2_ORDER r1, r2
mov r0, r0, lsr r2
ret lr
UNWIND(.fnend)
ENDPROC(__udivsi3)
ENDPROC(__aeabi_uidiv)
ENTRY(__umodsi3)
UNWIND(.fnstart)
subs r2, r1, #1 @ compare divisor with 1
bcc 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
retls lr
ARM_MOD_BODY r0, r1, r2, r3
ret lr
UNWIND(.fnend)
ENDPROC(__umodsi3)
ENTRY(__divsi3)
ENTRY(__aeabi_idiv)
UNWIND(.fnstart)
cmp r1, #0
eor ip, r0, r1 @ save the sign of the result.
beq Ldiv0
......@@ -116,28 +262,90 @@ ENTRY(__aeabi_idiv)
cmp ip, #0
rsbmi r0, r0, #0
mov pc, lr
ret lr
10: teq ip, r0 @ same sign ?
rsbmi r0, r0, #0
mov pc, lr
ret lr
11: movlo r0, #0
moveq r0, ip, asr #31
orreq r0, r0, #1
mov pc, lr
ret lr
12: ARM_DIV2_ORDER r1, r2
cmp ip, #0
mov r0, r3, lsr r2
rsbmi r0, r0, #0
mov pc, lr
ret lr
Ldiv0:
UNWIND(.fnend)
ENDPROC(__divsi3)
ENDPROC(__aeabi_idiv)
ENTRY(__modsi3)
UNWIND(.fnstart)
cmp r1, #0
beq 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 lr
str lr, [sp, #-4]!
UNWIND(.fnend)
ENDPROC(__modsi3)
#ifdef CONFIG_AEABI
ENTRY(__aeabi_uidivmod)
UNWIND(.fnstart)
UNWIND(.save {r0, r1, ip, lr} )
stmfd sp!, {r0, r1, ip, lr}
bl __aeabi_uidiv
ldmfd sp!, {r1, r2, ip, lr}
mul r3, r0, r2
sub r1, r1, r3
ret lr
UNWIND(.fnend)
ENDPROC(__aeabi_uidivmod)
ENTRY(__aeabi_idivmod)
UNWIND(.fnstart)
UNWIND(.save {r0, r1, ip, lr} )
stmfd sp!, {r0, r1, ip, lr}
bl __aeabi_idiv
ldmfd sp!, {r1, r2, ip, lr}
mul r3, r0, r2
sub r1, r1, r3
ret lr
UNWIND(.fnend)
ENDPROC(__aeabi_idivmod)
#endif
Ldiv0:
UNWIND(.fnstart)
UNWIND(.pad #4)
UNWIND(.save {lr})
str lr, [sp, #-8]!
bl __div0
mov r0, #0 @ About as wrong as it could be.
ldr pc, [sp], #4
ENDPROC(__aeabi_idiv)
ldr pc, [sp], #8
UNWIND(.fnend)
ENDPROC(Ldiv0)
#include <linux/linkage.h>
.macro ARM_MOD_BODY dividend, divisor, order, spare
#if __LINUX_ARM_ARCH__ >= 5
clz \order, \divisor
clz \spare, \dividend
sub \order, \order, \spare
mov \divisor, \divisor, lsl \order
#else
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
@ 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:
.endm
.align 5
ENTRY(__modsi3)
cmp r1, #0
beq 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
mov pc, lr
ENDPROC(__modsi3)
Ldiv0:
str lr, [sp, #-4]!
bl __div0
mov r0, #0 @ About as wrong as it could be.
ldr pc, [sp], #4
#include <linux/linkage.h>
/* # 1 "libgcc1.S" */
@ libgcc1 routines for ARM cpu.
@ Division routines, written by Richard Earnshaw, (rearnsha@armltd.co.uk)
dividend .req r0
divisor .req r1
result .req r2
curbit .req r3
/* ip .req r12 */
/* sp .req r13 */
/* lr .req r14 */
/* pc .req r15 */
.text
.globl __udivsi3
.type __udivsi3 ,function
.globl __aeabi_uidiv
.type __aeabi_uidiv ,function
.align 0
__udivsi3:
__aeabi_uidiv:
cmp divisor, #0
beq Ldiv0
mov curbit, #1
mov result, #0
cmp dividend, divisor
bcc Lgot_result
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, #0x10000000
cmpcc divisor, dividend
movcc divisor, divisor, lsl #4
movcc curbit, curbit, lsl #4
bcc Loop1
Lbignum:
@ For very big divisors, we must shift it a bit at a time, or
@ we will be in danger of overflowing.
cmp divisor, #0x80000000
cmpcc divisor, dividend
movcc divisor, divisor, lsl #1
movcc curbit, curbit, lsl #1
bcc Lbignum
Loop3:
@ Test for possible subtractions, 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
subcs dividend, dividend, divisor
orrcs result, result, curbit
cmp dividend, divisor, lsr #1
subcs dividend, dividend, divisor, lsr #1
orrcs result, result, curbit, lsr #1
cmp dividend, divisor, lsr #2
subcs dividend, dividend, divisor, lsr #2
orrcs result, result, curbit, lsr #2
cmp dividend, divisor, lsr #3
subcs dividend, dividend, divisor, lsr #3
orrcs 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 Loop3
Lgot_result:
mov r0, result
mov pc, lr
Ldiv0:
str lr, [sp, #-4]!
bl __div0 (PLT)
mov r0, #0 @ about as wrong as it could be
ldmia sp!, {pc}
.size __udivsi3 , . - __udivsi3
ENTRY(__aeabi_uidivmod)
stmfd sp!, {r0, r1, ip, lr}
bl __aeabi_uidiv
ldmfd sp!, {r1, r2, ip, lr}
mul r3, r0, r2
sub r1, r1, r3
mov pc, lr
ENDPROC(__aeabi_uidivmod)
ENTRY(__aeabi_idivmod)
stmfd sp!, {r0, r1, ip, lr}
bl __aeabi_idiv
ldmfd sp!, {r1, r2, ip, lr}
mul r3, r0, r2
sub r1, r1, r3
mov pc, lr
ENDPROC(__aeabi_idivmod)
#include <linux/linkage.h>
/* # 1 "libgcc1.S" */
@ libgcc1 routines for ARM cpu.
@ Division routines, written by Richard Earnshaw, (rearnsha@armltd.co.uk)
/* # 145 "libgcc1.S" */
dividend .req r0
divisor .req r1
overdone .req r2
curbit .req r3
/* ip .req r12 */
/* sp .req r13 */
/* lr .req r14 */
/* pc .req r15 */
.text
.type __umodsi3 ,function
.align 0
ENTRY(__umodsi3)
cmp divisor, #0
beq Ldiv0
mov curbit, #1
cmp dividend, divisor
movcc pc, lr
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, #0x10000000
cmpcc divisor, dividend
movcc divisor, divisor, lsl #4
movcc curbit, curbit, lsl #4
bcc Loop1
Lbignum:
@ For very big divisors, we must shift it a bit at a time, or
@ we will be in danger of overflowing.
cmp divisor, #0x80000000
cmpcc divisor, dividend
movcc divisor, divisor, lsl #1
movcc curbit, curbit, lsl #1
bcc Lbignum
Loop3:
@ Test for possible subtractions. 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
subcs dividend, dividend, divisor
cmp dividend, divisor, lsr #1
subcs dividend, dividend, divisor, lsr #1
orrcs overdone, overdone, curbit, ror #1
cmp dividend, divisor, lsr #2
subcs dividend, dividend, divisor, lsr #2
orrcs overdone, overdone, curbit, ror #2
cmp dividend, divisor, lsr #3
subcs dividend, dividend, divisor, lsr #3
orrcs overdone, overdone, curbit, ror #3
mov ip, curbit
cmp dividend, #0 @ Early termination?
movnes curbit, curbit, lsr #4 @ No, any more bits to do?
movne divisor, divisor, lsr #4
bne Loop3
@ 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.
@ If we terminated early, because dividend became zero,
@ then none of the below will match, since the bit in ip will not be
@ in the bottom nibble.
ands overdone, overdone, #0xe0000000
moveq pc, lr @ No fixups needed
tst overdone, ip, ror #3
addne dividend, dividend, divisor, lsr #3
tst overdone, ip, ror #2
addne dividend, dividend, divisor, lsr #2
tst overdone, ip, ror #1
addne dividend, dividend, divisor, lsr #1
mov pc, lr
Ldiv0:
str lr, [sp, #-4]!
bl __div0 (PLT)
mov r0, #0 @ about as wrong as it could be
ldmia sp!, {pc}
.size __umodsi3 , . - __umodsi3
/* # 320 "libgcc1.S" */
/* # 421 "libgcc1.S" */
/* # 433 "libgcc1.S" */
/* # 456 "libgcc1.S" */
/* # 500 "libgcc1.S" */
/* # 580 "libgcc1.S" */
ENDPROC(__umodsi3)
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