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authorRich Felker <dalias@aerifal.cx>2016-01-20 00:35:05 +0000
committerRich Felker <dalias@aerifal.cx>2016-01-20 00:35:05 +0000
commitcb1875eb4ff755fe6c5d1909f64fc4be1ee396ab (patch)
tree254b868756229957d618c13c98a2663b30779d35 /src/string/armel/memcpy.s
parent9514e70c60649ea13c25e1ac1e944cee7c82c9a7 (diff)
downloadmusl-cb1875eb4ff755fe6c5d1909f64fc4be1ee396ab.tar.gz
musl-cb1875eb4ff755fe6c5d1909f64fc4be1ee396ab.tar.xz
musl-cb1875eb4ff755fe6c5d1909f64fc4be1ee396ab.zip
adapt build of arm memcpy asm not to use .sub files
this depends on commit 9f5eb77992b42d484d69e879d24ef86466f20f21, which
made it possible to use a .c file for arch-specific replacements, and on
commit 2f853dd6b9a95d5b13ee8f9df762125e0588df5d, the out-of-tree build
support, which made it so that src/*/$(ARCH)/* 'replacement' files get
used even if they don't match the base name of a .c file in the parent
directory.
Diffstat (limited to 'src/string/armel/memcpy.s')
-rw-r--r--src/string/armel/memcpy.s379
1 files changed, 0 insertions, 379 deletions
diff --git a/src/string/armel/memcpy.s b/src/string/armel/memcpy.s
deleted file mode 100644
index b16be0d6..00000000
--- a/src/string/armel/memcpy.s
+++ /dev/null
@@ -1,379 +0,0 @@
-/*
- * Copyright (C) 2008 The Android Open Source Project
- * All rights reserved.
- *
- * Redistribution and use in source and binary forms, with or without
- * modification, are permitted provided that the following conditions
- * are met:
- *  * Redistributions of source code must retain the above copyright
- *    notice, this list of conditions and the following disclaimer.
- *  * Redistributions in binary form must reproduce the above copyright
- *    notice, this list of conditions and the following disclaimer in
- *    the documentation and/or other materials provided with the
- *    distribution.
- *
- * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
- * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
- * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
- * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
- * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
- * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
- * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
- * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
- * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
- * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT
- * OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
- * SUCH DAMAGE.
- */
-
-
-/*
- * Optimized memcpy() for ARM.
- *
- * note that memcpy() always returns the destination pointer,
- * so we have to preserve R0.
-  */
-
-/*
- * This file has been modified from the original for use in musl libc.
- * The main changes are: addition of .type memcpy,%function to make the
- * code safely callable from thumb mode, adjusting the return
- * instructions to be compatible with pre-thumb ARM cpus, and removal
- * of prefetch code that is not compatible with older cpus.
- */
-
-.syntax unified
-
-.global memcpy
-.type memcpy,%function
-memcpy:
-	/* The stack must always be 64-bits aligned to be compliant with the
-	 * 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 */
-	ldrbmi r3, [r1], #1
-	ldrbcs r4, [r1], #1
-	ldrbcs r12,[r1], #1
-	strbmi r3, [r0], #1
-	strbcs r4, [r0], #1
-	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
-
-congruent_aligned32:
-	/*
-	 * 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
-
-less_than_32_left:
-	/*
-	 * less than 32 bytes left at this point (length in r2)
-	 */
-
-	/* skip all this if there is nothing to do, which should
-	 * 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 */
-	ldrhmi r4, [r1], #2                     /*  2 bytes */
-	strcs   r3, [r0], #4
-	strhmi r4, [r0], #2
-	tst     r2, #0x1
-	ldrbne r3, [r1]                         /*  last byte  */
-	strbne r3, [r0]
-
-	/* we're done! restore everything and return */
-1:      ldmfd   sp!, {r5-r11}
-	ldmfd   sp!, {r0, r4, lr}
-	bx      lr
-
-	/********************************************************************/
-
-non_congruent:
-	/*
-	 * here source is aligned to 4 bytes
-	 * but destination is not.
-	 *
-	 * in the code below r2 is the number of bytes read
-	 * (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
-	strbmi r3, [r0], #1
-	movmi   r3, r3, lsr #8
-	strbcs r3, [r0], #1
-	movcs   r3, r3, lsr #8
-	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
-
-	/* 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
-
-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
-
-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
-
-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
-
-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
-
-partial_word_tail:
-	/* we have a partial word in the input buffer */
-	movs    r5, lr, lsl #(31-3)
-	strbmi r3, [r0], #1
-	movmi   r3, r3, lsr #8
-	strbcs r3, [r0], #1
-	movcs   r3, r3, lsr #8
-	strbcs r3, [r0], #1
-
-	/* 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 */
-	ldrbmi r2, [r1], #1
-	ldrbcs r3, [r1], #1
-	ldrbcs r12,[r1]
-	strbmi r2, [r0], #1
-	strbcs r3, [r0], #1
-	strbcs r12,[r0]
-
-	/* we're done! restore sp and spilled registers and return */
-	add     sp,  sp, #28
-	ldmfd   sp!, {r0, r4, lr}
-	bx      lr