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When CONFIG_SYS_THUMB_BUILD is defined these functions may be called from Thumb code. Add the required ENTRY and ENDPROC bracketing so that BLX is used to call these ARM functions, instead of plain BL, which will fail. Signed-off-by: Simon Glass <sjg@chromium.org> Reported-by: Pavel Machek <pavel@denx.de>
144 lines
3.1 KiB
ArmAsm
144 lines
3.1 KiB
ArmAsm
#include <linux/linkage.h>
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.macro ARM_DIV_BODY dividend, divisor, result, curbit
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#if __LINUX_ARM_ARCH__ >= 5
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clz \curbit, \divisor
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clz \result, \dividend
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sub \result, \curbit, \result
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mov \curbit, #1
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mov \divisor, \divisor, lsl \result
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mov \curbit, \curbit, lsl \result
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mov \result, #0
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#else
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@ Initially shift the divisor left 3 bits if possible,
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@ set curbit accordingly. This allows for curbit to be located
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@ at the left end of each 4 bit nibbles in the division loop
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@ to save one loop in most cases.
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tst \divisor, #0xe0000000
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moveq \divisor, \divisor, lsl #3
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moveq \curbit, #8
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movne \curbit, #1
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@ Unless the divisor is very big, shift it up in multiples of
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@ four bits, since this is the amount of unwinding in the main
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@ division loop. Continue shifting until the divisor is
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@ larger than the dividend.
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1: cmp \divisor, #0x10000000
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cmplo \divisor, \dividend
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movlo \divisor, \divisor, lsl #4
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movlo \curbit, \curbit, lsl #4
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blo 1b
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@ For very big divisors, we must shift it a bit at a time, or
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@ we will be in danger of overflowing.
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1: cmp \divisor, #0x80000000
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cmplo \divisor, \dividend
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movlo \divisor, \divisor, lsl #1
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movlo \curbit, \curbit, lsl #1
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blo 1b
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mov \result, #0
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#endif
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@ Division loop
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1: cmp \dividend, \divisor
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subhs \dividend, \dividend, \divisor
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orrhs \result, \result, \curbit
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cmp \dividend, \divisor, lsr #1
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subhs \dividend, \dividend, \divisor, lsr #1
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orrhs \result, \result, \curbit, lsr #1
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cmp \dividend, \divisor, lsr #2
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subhs \dividend, \dividend, \divisor, lsr #2
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orrhs \result, \result, \curbit, lsr #2
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cmp \dividend, \divisor, lsr #3
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subhs \dividend, \dividend, \divisor, lsr #3
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orrhs \result, \result, \curbit, lsr #3
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cmp \dividend, #0 @ Early termination?
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movnes \curbit, \curbit, lsr #4 @ No, any more bits to do?
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movne \divisor, \divisor, lsr #4
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bne 1b
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.endm
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.macro ARM_DIV2_ORDER divisor, order
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#if __LINUX_ARM_ARCH__ >= 5
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clz \order, \divisor
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rsb \order, \order, #31
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#else
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cmp \divisor, #(1 << 16)
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movhs \divisor, \divisor, lsr #16
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movhs \order, #16
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movlo \order, #0
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cmp \divisor, #(1 << 8)
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movhs \divisor, \divisor, lsr #8
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addhs \order, \order, #8
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cmp \divisor, #(1 << 4)
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movhs \divisor, \divisor, lsr #4
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addhs \order, \order, #4
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cmp \divisor, #(1 << 2)
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addhi \order, \order, #3
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addls \order, \order, \divisor, lsr #1
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#endif
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.endm
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.align 5
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.globl __divsi3
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__divsi3:
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ENTRY(__aeabi_idiv)
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cmp r1, #0
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eor ip, r0, r1 @ save the sign of the result.
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beq Ldiv0
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rsbmi r1, r1, #0 @ loops below use unsigned.
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subs r2, r1, #1 @ division by 1 or -1 ?
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beq 10f
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movs r3, r0
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rsbmi r3, r0, #0 @ positive dividend value
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cmp r3, r1
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bls 11f
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tst r1, r2 @ divisor is power of 2 ?
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beq 12f
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ARM_DIV_BODY r3, r1, r0, r2
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cmp ip, #0
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rsbmi r0, r0, #0
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mov pc, lr
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10: teq ip, r0 @ same sign ?
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rsbmi r0, r0, #0
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mov pc, lr
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11: movlo r0, #0
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moveq r0, ip, asr #31
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orreq r0, r0, #1
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mov pc, lr
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12: ARM_DIV2_ORDER r1, r2
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cmp ip, #0
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mov r0, r3, lsr r2
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rsbmi r0, r0, #0
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mov pc, lr
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Ldiv0:
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str lr, [sp, #-4]!
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bl __div0
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mov r0, #0 @ About as wrong as it could be.
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ldr pc, [sp], #4
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ENDPROC(__aeabi_idiv)
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