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-rw-r--r--src/string/armel/memcpy.s558
1 files changed, 279 insertions, 279 deletions
diff --git a/src/string/armel/memcpy.s b/src/string/armel/memcpy.s
index 656cad95..9c5e38d3 100644
--- a/src/string/armel/memcpy.s
+++ b/src/string/armel/memcpy.s
@@ -49,113 +49,113 @@ memcpy:
 	 * ARM ABI. Since we have to save R0, we might as well save R4
 	 * which we can use for better pipelining of the reads below
 	 */
-        .fnstart
-        .save       {r0, r4, lr}
-        stmfd       sp!, {r0, r4, lr}
-        /* Making room for r5-r11 which will be spilled later */
-        .pad        #28
-        sub         sp, sp, #28
-
-        /* it simplifies things to take care of len<4 early */
-        cmp	r2, #4
-        blo	copy_last_3_and_return
-
-        /* compute the offset to align the source
-         * offset = (4-(src&3))&3 = -src & 3
-         */
-        rsb	r3, r1, #0
-        ands	r3, r3, #3
-        beq	src_aligned
-
-        /* align source to 32 bits. We need to insert 2 instructions between
-         * a ldr[b|h] and str[b|h] because byte and half-word instructions
-         * stall 2 cycles.
-         */
-        movs	r12, r3, lsl #31
-        sub	r2, r2, r3		/* we know that r3 <= r2 because r2 >= 4 */
-        .word 0x44d13001 /* ldrbmi r3, [r1], #1 */
-        .word 0x24d14001 /* ldrbcs r4, [r1], #1 */
-        .word 0x24d1c001 /* ldrbcs r12,[r1], #1 */
-        .word 0x44c03001 /* strbmi r3, [r0], #1 */
-        .word 0x24c04001 /* strbcs r4, [r0], #1 */
-        .word 0x24c0c001 /* strbcs r12,[r0], #1 */
+	.fnstart
+	.save       {r0, r4, lr}
+	stmfd       sp!, {r0, r4, lr}
+	/* Making room for r5-r11 which will be spilled later */
+	.pad        #28
+	sub         sp, sp, #28
+
+	/* it simplifies things to take care of len<4 early */
+	cmp     r2, #4
+	blo     copy_last_3_and_return
+
+	/* compute the offset to align the source
+	 * offset = (4-(src&3))&3 = -src & 3
+	 */
+	rsb     r3, r1, #0
+	ands    r3, r3, #3
+	beq     src_aligned
+
+	/* align source to 32 bits. We need to insert 2 instructions between
+	 * a ldr[b|h] and str[b|h] because byte and half-word instructions
+	 * stall 2 cycles.
+	 */
+	movs    r12, r3, lsl #31
+	sub     r2, r2, r3              /* we know that r3 <= r2 because r2 >= 4 */
+	.word 0x44d13001 /* ldrbmi r3, [r1], #1 */
+	.word 0x24d14001 /* ldrbcs r4, [r1], #1 */
+	.word 0x24d1c001 /* ldrbcs r12,[r1], #1 */
+	.word 0x44c03001 /* strbmi r3, [r0], #1 */
+	.word 0x24c04001 /* strbcs r4, [r0], #1 */
+	.word 0x24c0c001 /* strbcs r12,[r0], #1 */
 
 src_aligned:
 
 	/* see if src and dst are aligned together (congruent) */
-	eor	r12, r0, r1
-        tst	r12, #3
-        bne	non_congruent
-
-        /* Use post-incriment mode for stm to spill r5-r11 to reserved stack
-         * frame. Don't update sp.
-         */
-        stmea	sp, {r5-r11}
-
-        /* align the destination to a cache-line */
-        rsb	r3, r0, #0
-        ands	r3, r3, #0x1C
-        beq    	congruent_aligned32
-        cmp    	r3, r2
-        andhi	r3, r2, #0x1C
-
-        /* conditionnaly copies 0 to 7 words (length in r3) */
-        movs	r12, r3, lsl #28
-        ldmcs	r1!, {r4, r5, r6, r7}		/* 16 bytes */
-        ldmmi	r1!, {r8, r9}			/*  8 bytes */
-        stmcs	r0!, {r4, r5, r6, r7}
-        stmmi	r0!, {r8, r9}
-        tst    	r3, #0x4
-        ldrne	r10,[r1], #4			/*  4 bytes */
-        strne	r10,[r0], #4
-        sub    	r2, r2, r3
+	eor     r12, r0, r1
+	tst     r12, #3
+	bne     non_congruent
+
+	/* Use post-incriment mode for stm to spill r5-r11 to reserved stack
+	 * frame. Don't update sp.
+	 */
+	stmea   sp, {r5-r11}
+
+	/* align the destination to a cache-line */
+	rsb     r3, r0, #0
+	ands    r3, r3, #0x1C
+	beq     congruent_aligned32
+	cmp     r3, r2
+	andhi   r3, r2, #0x1C
+
+	/* conditionnaly copies 0 to 7 words (length in r3) */
+	movs    r12, r3, lsl #28
+	ldmcs   r1!, {r4, r5, r6, r7}           /* 16 bytes */
+	ldmmi   r1!, {r8, r9}                   /*  8 bytes */
+	stmcs   r0!, {r4, r5, r6, r7}
+	stmmi   r0!, {r8, r9}
+	tst     r3, #0x4
+	ldrne   r10,[r1], #4                    /*  4 bytes */
+	strne   r10,[r0], #4
+	sub     r2, r2, r3
 
 congruent_aligned32:
 	/*
- 	 * here source is aligned to 32 bytes.
- 	 */
+	 * here source is aligned to 32 bytes.
+	 */
 
 cached_aligned32:
-        subs   	r2, r2, #32
-        blo    	less_than_32_left
-
-        /*
-         * We preload a cache-line up to 64 bytes ahead. On the 926, this will
-         * stall only until the requested world is fetched, but the linefill
-         * continues in the the background.
-         * While the linefill is going, we write our previous cache-line
-         * into the write-buffer (which should have some free space).
-         * When the linefill is done, the writebuffer will
-         * start dumping its content into memory
-         *
-         * While all this is going, we then load a full cache line into
-         * 8 registers, this cache line should be in the cache by now
-         * (or partly in the cache).
-         *
-         * This code should work well regardless of the source/dest alignment.
-         *
-         */
-
-        /* Align the preload register to a cache-line because the cpu does
-         * "critical word first" (the first word requested is loaded first).
-         */
-        @ bic    	r12, r1, #0x1F
-        @ add    	r12, r12, #64
-
-1:      ldmia  	r1!, { r4-r11 }
-        subs   	r2, r2, #32
-
-        /* 
-         * NOTE: if r12 is more than 64 ahead of r1, the following ldrhi
-         * for ARM9 preload will not be safely guarded by the preceding subs.
-         * When it is safely guarded the only possibility to have SIGSEGV here
-         * is because the caller overstates the length.
-         */
-        @ ldrhi  	r3, [r12], #32      /* cheap ARM9 preload */
-        stmia  	r0!, { r4-r11 }
-	bhs    	1b
-
-        add	r2, r2, #32
+	subs    r2, r2, #32
+	blo     less_than_32_left
+
+	/*
+	 * We preload a cache-line up to 64 bytes ahead. On the 926, this will
+	 * stall only until the requested world is fetched, but the linefill
+	 * continues in the the background.
+	 * While the linefill is going, we write our previous cache-line
+	 * into the write-buffer (which should have some free space).
+	 * When the linefill is done, the writebuffer will
+	 * start dumping its content into memory
+	 *
+	 * While all this is going, we then load a full cache line into
+	 * 8 registers, this cache line should be in the cache by now
+	 * (or partly in the cache).
+	 *
+	 * This code should work well regardless of the source/dest alignment.
+	 *
+	 */
+
+	/* Align the preload register to a cache-line because the cpu does
+	 * "critical word first" (the first word requested is loaded first).
+	 */
+	@ bic           r12, r1, #0x1F
+	@ add           r12, r12, #64
+
+1:      ldmia   r1!, { r4-r11 }
+	subs    r2, r2, #32
+
+	/* 
+	 * NOTE: if r12 is more than 64 ahead of r1, the following ldrhi
+	 * for ARM9 preload will not be safely guarded by the preceding subs.
+	 * When it is safely guarded the only possibility to have SIGSEGV here
+	 * is because the caller overstates the length.
+	 */
+	@ ldrhi         r3, [r12], #32      /* cheap ARM9 preload */
+	stmia   r0!, { r4-r11 }
+	bhs     1b
+
+	add     r2, r2, #32
 
 less_than_32_left:
 	/*
@@ -166,30 +166,30 @@ less_than_32_left:
 	 * be a common case (if not executed the code below takes
 	 * about 16 cycles)
 	 */
-	tst	r2, #0x1F
-        beq	1f
-
-        /* conditionnaly copies 0 to 31 bytes */
-        movs	r12, r2, lsl #28
-        ldmcs	r1!, {r4, r5, r6, r7}		/* 16 bytes */
-        ldmmi	r1!, {r8, r9}			/*  8 bytes */
-        stmcs	r0!, {r4, r5, r6, r7}
-        stmmi	r0!, {r8, r9}
-        movs	r12, r2, lsl #30
-        ldrcs	r3, [r1], #4			/*  4 bytes */
-        .word 0x40d140b2 /* ldrhmi r4, [r1], #2 */ /*  2 bytes */
-        strcs	r3, [r0], #4
-        .word 0x40c040b2 /* strhmi r4, [r0], #2 */
-        tst    	r2, #0x1
-        .word 0x15d13000 /* ldrbne r3, [r1] */	/*  last byte  */
-        .word 0x15c03000 /* strbne r3, [r0] */
-
-        /* we're done! restore everything and return */
-1:	ldmfd	sp!, {r5-r11}
-        ldmfd	sp!, {r0, r4, lr}
-        tst	lr, #1
-        moveq	pc, lr
-        bx	lr
+	tst     r2, #0x1F
+	beq     1f
+
+	/* conditionnaly copies 0 to 31 bytes */
+	movs    r12, r2, lsl #28
+	ldmcs   r1!, {r4, r5, r6, r7}           /* 16 bytes */
+	ldmmi   r1!, {r8, r9}                   /*  8 bytes */
+	stmcs   r0!, {r4, r5, r6, r7}
+	stmmi   r0!, {r8, r9}
+	movs    r12, r2, lsl #30
+	ldrcs   r3, [r1], #4                    /*  4 bytes */
+	.word 0x40d140b2 /* ldrhmi r4, [r1], #2 */ /*  2 bytes */
+	strcs   r3, [r0], #4
+	.word 0x40c040b2 /* strhmi r4, [r0], #2 */
+	tst     r2, #0x1
+	.word 0x15d13000 /* ldrbne r3, [r1] */  /*  last byte  */
+	.word 0x15c03000 /* strbne r3, [r0] */
+
+	/* we're done! restore everything and return */
+1:      ldmfd   sp!, {r5-r11}
+	ldmfd   sp!, {r0, r4, lr}
+	tst     lr, #1
+	moveq   pc, lr
+	bx      lr
 
 	/********************************************************************/
 
@@ -202,180 +202,180 @@ non_congruent:
 	 * (the number of bytes written is always smaller, because we have
 	 * partial words in the shift queue)
 	 */
-	cmp	r2, #4
-	blo	copy_last_3_and_return
-
-        /* Use post-incriment mode for stm to spill r5-r11 to reserved stack
-         * frame. Don't update sp.
-         */
-        stmea	sp, {r5-r11}
-
-        /* compute shifts needed to align src to dest */
-        rsb	r5, r0, #0
-        and	r5, r5, #3			/* r5 = # bytes in partial words */
-        mov	r12, r5, lsl #3		/* r12 = right */
-        rsb	lr, r12, #32		/* lr = left  */
-
-        /* read the first word */
-        ldr	r3, [r1], #4
-        sub	r2, r2, #4
-
-        /* write a partial word (0 to 3 bytes), such that destination
-         * becomes aligned to 32 bits (r5 = nb of words to copy for alignment)
-         */
-        movs	r5, r5, lsl #31
-        .word 0x44c03001 /* strbmi r3, [r0], #1 */
-        movmi	r3, r3, lsr #8
-        .word 0x24c03001 /* strbcs r3, [r0], #1 */
-        movcs	r3, r3, lsr #8
-        .word 0x24c03001 /* strbcs r3, [r0], #1 */
-        movcs	r3, r3, lsr #8
-
-        cmp	r2, #4
-        blo	partial_word_tail
-
-        /* Align destination to 32 bytes (cache line boundary) */
-1:	tst	r0, #0x1c
-        beq	2f
-        ldr	r5, [r1], #4
-        sub    	r2, r2, #4
-        orr	r4, r3, r5,		lsl lr
-        mov	r3, r5,			lsr r12
-        str	r4, [r0], #4
-        cmp    	r2, #4
-        bhs	1b
-        blo	partial_word_tail
+	cmp     r2, #4
+	blo     copy_last_3_and_return
+
+	/* Use post-incriment mode for stm to spill r5-r11 to reserved stack
+	 * frame. Don't update sp.
+	 */
+	stmea   sp, {r5-r11}
+
+	/* compute shifts needed to align src to dest */
+	rsb     r5, r0, #0
+	and     r5, r5, #3                      /* r5 = # bytes in partial words */
+	mov     r12, r5, lsl #3         /* r12 = right */
+	rsb     lr, r12, #32            /* lr = left  */
+
+	/* read the first word */
+	ldr     r3, [r1], #4
+	sub     r2, r2, #4
+
+	/* write a partial word (0 to 3 bytes), such that destination
+	 * becomes aligned to 32 bits (r5 = nb of words to copy for alignment)
+	 */
+	movs    r5, r5, lsl #31
+	.word 0x44c03001 /* strbmi r3, [r0], #1 */
+	movmi   r3, r3, lsr #8
+	.word 0x24c03001 /* strbcs r3, [r0], #1 */
+	movcs   r3, r3, lsr #8
+	.word 0x24c03001 /* strbcs r3, [r0], #1 */
+	movcs   r3, r3, lsr #8
+
+	cmp     r2, #4
+	blo     partial_word_tail
+
+	/* Align destination to 32 bytes (cache line boundary) */
+1:      tst     r0, #0x1c
+	beq     2f
+	ldr     r5, [r1], #4
+	sub     r2, r2, #4
+	orr     r4, r3, r5,             lsl lr
+	mov     r3, r5,                 lsr r12
+	str     r4, [r0], #4
+	cmp     r2, #4
+	bhs     1b
+	blo     partial_word_tail
 
 	/* copy 32 bytes at a time */
-2:	subs	r2, r2, #32
-	blo	less_than_thirtytwo
+2:      subs    r2, r2, #32
+	blo     less_than_thirtytwo
 
-        /* Use immediate mode for the shifts, because there is an extra cycle
-         * for register shifts, which could account for up to 50% of
-         * performance hit.
-         */
+	/* Use immediate mode for the shifts, because there is an extra cycle
+	 * for register shifts, which could account for up to 50% of
+	 * performance hit.
+	 */
 
-        cmp	r12, #24
-        beq	loop24
-        cmp	r12, #8
-        beq	loop8
+	cmp     r12, #24
+	beq     loop24
+	cmp     r12, #8
+	beq     loop8
 
 loop16:
-        ldr    	r12, [r1], #4
-1:      mov    	r4, r12
-	ldmia	r1!, {   r5,r6,r7,  r8,r9,r10,r11}
-        subs   	r2, r2, #32
-        ldrhs  	r12, [r1], #4
-	orr	r3, r3, r4, lsl #16
-        mov	r4, r4, lsr #16
-        orr	r4, r4, r5, lsl #16
-        mov	r5, r5, lsr #16
-        orr	r5, r5, r6, lsl #16
-        mov	r6, r6, lsr #16
-        orr	r6, r6, r7, lsl #16
-        mov	r7, r7, lsr #16
-        orr	r7, r7, r8, lsl #16
-        mov	r8, r8, lsr #16
-        orr	r8, r8, r9, lsl #16
-        mov	r9, r9, lsr #16
-        orr	r9, r9, r10, lsl #16
-        mov	r10, r10,		lsr #16
-        orr	r10, r10, r11, lsl #16
-        stmia	r0!, {r3,r4,r5,r6, r7,r8,r9,r10}
-        mov	r3, r11, lsr #16
-        bhs	1b
-        b	less_than_thirtytwo
+	ldr     r12, [r1], #4
+1:      mov     r4, r12
+	ldmia   r1!, {   r5,r6,r7,  r8,r9,r10,r11}
+	subs    r2, r2, #32
+	ldrhs   r12, [r1], #4
+	orr     r3, r3, r4, lsl #16
+	mov     r4, r4, lsr #16
+	orr     r4, r4, r5, lsl #16
+	mov     r5, r5, lsr #16
+	orr     r5, r5, r6, lsl #16
+	mov     r6, r6, lsr #16
+	orr     r6, r6, r7, lsl #16
+	mov     r7, r7, lsr #16
+	orr     r7, r7, r8, lsl #16
+	mov     r8, r8, lsr #16
+	orr     r8, r8, r9, lsl #16
+	mov     r9, r9, lsr #16
+	orr     r9, r9, r10, lsl #16
+	mov     r10, r10,               lsr #16
+	orr     r10, r10, r11, lsl #16
+	stmia   r0!, {r3,r4,r5,r6, r7,r8,r9,r10}
+	mov     r3, r11, lsr #16
+	bhs     1b
+	b       less_than_thirtytwo
 
 loop8:
-        ldr    	r12, [r1], #4
-1:      mov    	r4, r12
-	ldmia	r1!, {   r5,r6,r7,  r8,r9,r10,r11}
-	subs	r2, r2, #32
-        ldrhs  	r12, [r1], #4
-        orr	r3, r3, r4, lsl #24
-        mov	r4, r4, lsr #8
-        orr	r4, r4, r5, lsl #24
-        mov	r5, r5, lsr #8
-        orr	r5, r5, r6, lsl #24
-        mov	r6, r6,	 lsr #8
-        orr	r6, r6, r7, lsl #24
-        mov	r7, r7,	 lsr #8
-        orr	r7, r7, r8,		lsl #24
-        mov	r8, r8,	 lsr #8
-        orr	r8, r8, r9,		lsl #24
-        mov	r9, r9,	 lsr #8
-        orr	r9, r9, r10,	lsl #24
-        mov	r10, r10, lsr #8
-        orr	r10, r10, r11,	lsl #24
-        stmia	r0!, {r3,r4,r5,r6, r7,r8,r9,r10}
-        mov	r3, r11, lsr #8
-        bhs	1b
-        b	less_than_thirtytwo
+	ldr     r12, [r1], #4
+1:      mov     r4, r12
+	ldmia   r1!, {   r5,r6,r7,  r8,r9,r10,r11}
+	subs    r2, r2, #32
+	ldrhs   r12, [r1], #4
+	orr     r3, r3, r4, lsl #24
+	mov     r4, r4, lsr #8
+	orr     r4, r4, r5, lsl #24
+	mov     r5, r5, lsr #8
+	orr     r5, r5, r6, lsl #24
+	mov     r6, r6,  lsr #8
+	orr     r6, r6, r7, lsl #24
+	mov     r7, r7,  lsr #8
+	orr     r7, r7, r8,             lsl #24
+	mov     r8, r8,  lsr #8
+	orr     r8, r8, r9,             lsl #24
+	mov     r9, r9,  lsr #8
+	orr     r9, r9, r10,    lsl #24
+	mov     r10, r10, lsr #8
+	orr     r10, r10, r11,  lsl #24
+	stmia   r0!, {r3,r4,r5,r6, r7,r8,r9,r10}
+	mov     r3, r11, lsr #8
+	bhs     1b
+	b       less_than_thirtytwo
 
 loop24:
-        ldr    	r12, [r1], #4
-1:      mov    	r4, r12
-	ldmia	r1!, {   r5,r6,r7,  r8,r9,r10,r11}
-        subs	r2, r2, #32
-        ldrhs  	r12, [r1], #4
-        orr	r3, r3, r4, lsl #8
-        mov	r4, r4, lsr #24
-        orr	r4, r4, r5, lsl #8
-        mov	r5, r5, lsr #24
-        orr	r5, r5, r6, lsl #8
-        mov	r6, r6, lsr #24
-        orr	r6, r6, r7, lsl #8
-        mov	r7, r7, lsr #24
-        orr	r7, r7, r8, lsl #8
-        mov	r8, r8, lsr #24
-        orr	r8, r8, r9, lsl #8
-        mov	r9, r9, lsr #24
-        orr	r9, r9, r10, lsl #8
-        mov	r10, r10, lsr #24
-        orr	r10, r10, r11, lsl #8
-        stmia	r0!, {r3,r4,r5,r6, r7,r8,r9,r10}
-        mov	r3, r11, lsr #24
-        bhs	1b
+	ldr     r12, [r1], #4
+1:      mov     r4, r12
+	ldmia   r1!, {   r5,r6,r7,  r8,r9,r10,r11}
+	subs    r2, r2, #32
+	ldrhs   r12, [r1], #4
+	orr     r3, r3, r4, lsl #8
+	mov     r4, r4, lsr #24
+	orr     r4, r4, r5, lsl #8
+	mov     r5, r5, lsr #24
+	orr     r5, r5, r6, lsl #8
+	mov     r6, r6, lsr #24
+	orr     r6, r6, r7, lsl #8
+	mov     r7, r7, lsr #24
+	orr     r7, r7, r8, lsl #8
+	mov     r8, r8, lsr #24
+	orr     r8, r8, r9, lsl #8
+	mov     r9, r9, lsr #24
+	orr     r9, r9, r10, lsl #8
+	mov     r10, r10, lsr #24
+	orr     r10, r10, r11, lsl #8
+	stmia   r0!, {r3,r4,r5,r6, r7,r8,r9,r10}
+	mov     r3, r11, lsr #24
+	bhs     1b
 
 less_than_thirtytwo:
 	/* copy the last 0 to 31 bytes of the source */
-	rsb	r12, lr, #32		/* we corrupted r12, recompute it  */
-        add	r2, r2, #32
-        cmp	r2, #4
-        blo	partial_word_tail
-
-1:	ldr	r5, [r1], #4
-        sub    	r2, r2, #4
-        orr	r4, r3, r5,		lsl lr
-        mov	r3,	r5,			lsr r12
-        str	r4, [r0], #4
-        cmp    	r2, #4
-        bhs	1b
+	rsb     r12, lr, #32            /* we corrupted r12, recompute it  */
+	add     r2, r2, #32
+	cmp     r2, #4
+	blo     partial_word_tail
+
+1:      ldr     r5, [r1], #4
+	sub     r2, r2, #4
+	orr     r4, r3, r5,             lsl lr
+	mov     r3,     r5,                     lsr r12
+	str     r4, [r0], #4
+	cmp     r2, #4
+	bhs     1b
 
 partial_word_tail:
 	/* we have a partial word in the input buffer */
-	movs	r5, lr, lsl #(31-3)
+	movs    r5, lr, lsl #(31-3)
 	.word 0x44c03001 /* strbmi r3, [r0], #1 */
-        movmi	r3, r3, lsr #8
-        .word 0x24c03001 /* strbcs r3, [r0], #1 */
-        movcs	r3, r3, lsr #8
-        .word 0x24c03001 /* strbcs r3, [r0], #1 */
+	movmi   r3, r3, lsr #8
+	.word 0x24c03001 /* strbcs r3, [r0], #1 */
+	movcs   r3, r3, lsr #8
+	.word 0x24c03001 /* strbcs r3, [r0], #1 */
 
-        /* Refill spilled registers from the stack. Don't update sp. */
-        ldmfd	sp, {r5-r11}
+	/* Refill spilled registers from the stack. Don't update sp. */
+	ldmfd   sp, {r5-r11}
 
 copy_last_3_and_return:
-	movs	r2, r2, lsl #31	/* copy remaining 0, 1, 2 or 3 bytes */
-        .word 0x44d12001 /* ldrbmi r2, [r1], #1 */
-        .word 0x24d13001 /* ldrbcs r3, [r1], #1 */
-        .word 0x25d1c000 /* ldrbcs r12,[r1] */
-        .word 0x44c02001 /* strbmi r2, [r0], #1 */
-        .word 0x24c03001 /* strbcs r3, [r0], #1 */
-        .word 0x25c0c000 /* strbcs r12,[r0] */
-
-        /* we're done! restore sp and spilled registers and return */
-        add    	sp,  sp, #28
-        ldmfd	sp!, {r0, r4, lr}
-        tst	lr, #1
-        moveq	pc, lr
-        bx	lr
+	movs    r2, r2, lsl #31 /* copy remaining 0, 1, 2 or 3 bytes */
+	.word 0x44d12001 /* ldrbmi r2, [r1], #1 */
+	.word 0x24d13001 /* ldrbcs r3, [r1], #1 */
+	.word 0x25d1c000 /* ldrbcs r12,[r1] */
+	.word 0x44c02001 /* strbmi r2, [r0], #1 */
+	.word 0x24c03001 /* strbcs r3, [r0], #1 */
+	.word 0x25c0c000 /* strbcs r12,[r0] */
+
+	/* we're done! restore sp and spilled registers and return */
+	add     sp,  sp, #28
+	ldmfd   sp!, {r0, r4, lr}
+	tst     lr, #1
+	moveq   pc, lr
+	bx      lr