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/*
 * Copyright © 2009 Nokia Corporation
 *
 * Permission to use, copy, modify, distribute, and sell this software and its
 * documentation for any purpose is hereby granted without fee, provided that
 * the above copyright notice appear in all copies and that both that
 * copyright notice and this permission notice appear in supporting
 * documentation, and that the name of Nokia Corporation not be used in
 * advertising or publicity pertaining to distribution of the software without
 * specific, written prior permission.  Nokia Corporation makes no
 * representations about the suitability of this software for any purpose.
 * It is provided "as is" without express or implied warranty.
 *
 * THE COPYRIGHT HOLDERS DISCLAIM ALL WARRANTIES WITH REGARD TO THIS
 * SOFTWARE, INCLUDING ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND
 * FITNESS, IN NO EVENT SHALL THE COPYRIGHT HOLDERS BE LIABLE FOR ANY
 * SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
 * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN
 * AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
 * SOFTWARE.
 *
 * Author:  Siarhei Siamashka (siarhei.siamashka@nokia.com)
 */

/*
 * This file contains implementations of NEON optimized pixel processing
 * functions. There is no full and detailed tutorial, but some functions
 * (those which are exposing some new or interesting features) are
 * extensively commented and can be used as examples.
 *
 * You may want to have a look at the comments for following functions:
 *  - pixman_composite_over_8888_0565_asm_neon
 *  - pixman_composite_over_n_8_0565_asm_neon
 */

/* Prevent the stack from becoming executable for no reason... */
#if defined(__linux__) && defined(__ELF__)
.section .note.GNU-stack,"",%progbits
#endif

    .text
    .fpu neon
    .altmacro

#include "pixman-arm-neon-asm.h"

/* Global configuration options and preferences */

/*
 * The code can optionally make use of unaligned memory accesses to improve
 * performance of handling leading/trailing pixels for each scanline.
 * Configuration variable RESPECT_STRICT_ALIGNMENT can be set to 0 for
 * example in linux if unaligned memory accesses are not configured to
 * generate.exceptions.
 */
.set RESPECT_STRICT_ALIGNMENT, 1

/*
 * Set default prefetch type. There is a choice between the following options:
 *
 * PREFETCH_TYPE_NONE (may be useful for the ARM cores where PLD is set to work
 * as NOP to workaround some HW bugs or for whatever other reason)
 *
 * PREFETCH_TYPE_SIMPLE (may be useful for simple single-issue ARM cores where
 * advanced prefetch intruduces heavy overhead)
 *
 * PREFETCH_TYPE_ADVANCED (useful for superscalar cores such as ARM Cortex-A8
 * which can run ARM and NEON instructions simultaneously so that extra ARM
 * instructions do not add (many) extra cycles, but improve prefetch efficiency)
 *
 * Note: some types of function can't support advanced prefetch and fallback
 *       to simple one (those which handle 24bpp pixels)
 */
.set PREFETCH_TYPE_DEFAULT, PREFETCH_TYPE_ADVANCED

/* Prefetch distance in pixels for simple prefetch */
.set PREFETCH_DISTANCE_SIMPLE, 64

/*
 * Implementation of pixman_composite_over_8888_0565_asm_neon
 *
 * This function takes a8r8g8b8 source buffer, r5g6b5 destination buffer and
 * performs OVER compositing operation. Function fast_composite_over_8888_0565
 * from pixman-fast-path.c does the same in C and can be used as a reference.
 *
 * First we need to have some NEON assembly code which can do the actual
 * operation on the pixels and provide it to the template macro.
 *
 * Template macro quite conveniently takes care of emitting all the necessary
 * code for memory reading and writing (including quite tricky cases of
 * handling unaligned leading/trailing pixels), so we only need to deal with
 * the data in NEON registers.
 *
 * NEON registers allocation in general is recommented to be the following:
 * d0,  d1,  d2,  d3  - contain loaded source pixel data
 * d4,  d5,  d6,  d7  - contain loaded destination pixels (if they are needed)
 * d24, d25, d26, d27 - contain loading mask pixel data (if mask is used)
 * d28, d29, d30, d31 - place for storing the result (destination pixels)
 *
 * As can be seen above, four 64-bit NEON registers are used for keeping
 * intermediate pixel data and up to 8 pixels can be processed in one step
 * for 32bpp formats (16 pixels for 16bpp, 32 pixels for 8bpp).
 *
 * This particular function uses the following registers allocation:
 * d0,  d1,  d2,  d3  - contain loaded source pixel data
 * d4,  d5            - contain loaded destination pixels (they are needed)
 * d28, d29           - place for storing the result (destination pixels)
 */

/*
 * Step one. We need to have some code to do some arithmetics on pixel data.
 * This is implemented as a pair of macros: '*_head' and '*_tail'. When used
 * back-to-back, they take pixel data from {d0, d1, d2, d3} and {d4, d5},
 * perform all the needed calculations and write the result to {d28, d29}.
 * The rationale for having two macros and not just one will be explained
 * later. In practice, any single monolitic function which does the work can
 * be split into two parts in any arbitrary way without affecting correctness.
 *
 * There is one special trick here too. Common template macro can optionally
 * make our life a bit easier by doing R, G, B, A color components
 * deinterleaving for 32bpp pixel formats (and this feature is used in
 * 'pixman_composite_over_8888_0565_asm_neon' function). So it means that
 * instead of having 8 packed pixels in {d0, d1, d2, d3} registers, we
 * actually use d0 register for blue channel (a vector of eight 8-bit
 * values), d1 register for green, d2 for red and d3 for alpha. This
 * simple conversion can be also done with a few NEON instructions:
 *
 * Packed to planar conversion:
 *  vuzp.8 d0, d1
 *  vuzp.8 d2, d3
 *  vuzp.8 d1, d3
 *  vuzp.8 d0, d2
 *
 * Planar to packed conversion:
 *  vzip.8 d0, d2
 *  vzip.8 d1, d3
 *  vzip.8 d2, d3
 *  vzip.8 d0, d1
 *
 * But pixel can be loaded directly in planar format using VLD4.8 NEON
 * instruction. It is 1 cycle slower than VLD1.32, so this is not always
 * desirable, that's why deinterleaving is optional.
 *
 * But anyway, here is the code:
 */
.macro pixman_composite_over_8888_0565_process_pixblock_head
    /* convert 8 r5g6b5 pixel data from {d4, d5} to planar 8-bit format
       and put data into d6 - red, d7 - green, d30 - blue */
    vshrn.u16   d6, q2, #8
    vshrn.u16   d7, q2, #3
    vsli.u16    q2, q2, #5
    vsri.u8     d6, d6, #5
    vmvn.8      d3, d3      /* invert source alpha */
    vsri.u8     d7, d7, #6
    vshrn.u16   d30, q2, #2
    /* now do alpha blending, storing results in 8-bit planar format
       into d16 - red, d19 - green, d18 - blue */
    vmull.u8    q10, d3, d6
    vmull.u8    q11, d3, d7
    vmull.u8    q12, d3, d30
    vrshr.u16   q13, q10, #8
    vrshr.u16   q3, q11, #8
    vrshr.u16   q15, q12, #8
    vraddhn.u16 d20, q10, q13
    vraddhn.u16 d23, q11, q3
    vraddhn.u16 d22, q12, q15
.endm

.macro pixman_composite_over_8888_0565_process_pixblock_tail
    /* ... continue alpha blending */
    vqadd.u8    d16, d2, d20
    vqadd.u8    q9, q0, q11
    /* convert the result to r5g6b5 and store it into {d28, d29} */
    vshll.u8    q14, d16, #8
    vshll.u8    q8, d19, #8
    vshll.u8    q9, d18, #8
    vsri.u16    q14, q8, #5
    vsri.u16    q14, q9, #11
.endm

/*
 * OK, now we got almost everything that we need. Using the above two
 * macros, the work can be done right. But now we want to optimize
 * it a bit. ARM Cortex-A8 is an in-order core, and benefits really
 * a lot from good code scheduling and software pipelining.
 *
 * Let's construct some code, which will run in the core main loop.
 * Some pseudo-code of the main loop will look like this:
 *   head
 *   while (...) {
 *     tail
 *     head
 *   }
 *   tail
 *
 * It may look a bit weird, but this setup allows to hide instruction
 * latencies better and also utilize dual-issue capability more
 * efficiently (make pairs of load-store and ALU instructions).
 *
 * So what we need now is a '*_tail_head' macro, which will be used
 * in the core main loop. A trivial straightforward implementation
 * of this macro would look like this:
 *
 *   pixman_composite_over_8888_0565_process_pixblock_tail
 *   vst1.16     {d28, d29}, [DST_W, :128]!
 *   vld1.16     {d4, d5}, [DST_R, :128]!
 *   vld4.32     {d0, d1, d2, d3}, [SRC]!
 *   pixman_composite_over_8888_0565_process_pixblock_head
 *   cache_preload 8, 8
 *
 * Now it also got some VLD/VST instructions. We simply can't move from
 * processing one block of pixels to the other one with just arithmetics.
 * The previously processed data needs to be written to memory and new
 * data needs to be fetched. Fortunately, this main loop does not deal
 * with partial leading/trailing pixels and can load/store a full block
 * of pixels in a bulk. Additionally, destination buffer is already
 * 16 bytes aligned here (which is good for performance).
 *
 * New things here are DST_R, DST_W, SRC and MASK identifiers. These
 * are the aliases for ARM registers which are used as pointers for
 * accessing data. We maintain separate pointers for reading and writing
 * destination buffer (DST_R and DST_W).
 *
 * Another new thing is 'cache_preload' macro. It is used for prefetching
 * data into CPU L2 cache and improve performance when dealing with large
 * images which are far larger than cache size. It uses one argument
 * (actually two, but they need to be the same here) - number of pixels
 * in a block. Looking into 'pixman-arm-neon-asm.h' can provide some
 * details about this macro. Moreover, if good performance is needed
 * the code from this macro needs to be copied into '*_tail_head' macro
 * and mixed with the rest of code for optimal instructions scheduling.
 * We are actually doing it below.
 *
 * Now after all the explanations, here is the optimized code.
 * Different instruction streams (originaling from '*_head', '*_tail'
 * and 'cache_preload' macro) use different indentation levels for
 * better readability. Actually taking the code from one of these
 * indentation levels and ignoring a few VLD/VST instructions would
 * result in exactly the code from '*_head', '*_tail' or 'cache_preload'
 * macro!
 */

#if 1

.macro pixman_composite_over_8888_0565_process_pixblock_tail_head
        vqadd.u8    d16, d2, d20
    vld1.16     {d4, d5}, [DST_R, :128]!
        vqadd.u8    q9, q0, q11
    vshrn.u16   d6, q2, #8
    vld4.8      {d0, d1, d2, d3}, [SRC]!
    vshrn.u16   d7, q2, #3
    vsli.u16    q2, q2, #5
        vshll.u8    q14, d16, #8
                                    PF add PF_X, PF_X, #8
        vshll.u8    q8, d19, #8
                                    PF tst PF_CTL, #0xF
    vsri.u8     d6, d6, #5
                                    PF addne PF_X, PF_X, #8
    vmvn.8      d3, d3
                                    PF subne PF_CTL, PF_CTL, #1
    vsri.u8     d7, d7, #6
    vshrn.u16   d30, q2, #2
    vmull.u8    q10, d3, d6
                                    PF pld, [PF_SRC, PF_X, lsl #src_bpp_shift]
    vmull.u8    q11, d3, d7
    vmull.u8    q12, d3, d30
                                    PF pld, [PF_DST, PF_X, lsl #dst_bpp_shift]
        vsri.u16    q14, q8, #5
                                    PF cmp PF_X, ORIG_W
        vshll.u8    q9, d18, #8
    vrshr.u16   q13, q10, #8
                                    PF subge PF_X, PF_X, ORIG_W
    vrshr.u16   q3, q11, #8
    vrshr.u16   q15, q12, #8
                                    PF subges PF_CTL, PF_CTL, #0x10
        vsri.u16    q14, q9, #11
                                    PF ldrgeb DUMMY, [PF_SRC, SRC_STRIDE, lsl #src_bpp_shift]!
    vraddhn.u16 d20, q10, q13
    vraddhn.u16 d23, q11, q3
                                    PF ldrgeb DUMMY, [PF_DST, DST_STRIDE, lsl #dst_bpp_shift]!
    vraddhn.u16 d22, q12, q15
        vst1.16     {d28, d29}, [DST_W, :128]!
.endm

#else

/* If we did not care much about the performance, we would just use this... */
.macro pixman_composite_over_8888_0565_process_pixblock_tail_head
    pixman_composite_over_8888_0565_process_pixblock_tail
    vst1.16     {d28, d29}, [DST_W, :128]!
    vld1.16     {d4, d5}, [DST_R, :128]!
    vld4.32     {d0, d1, d2, d3}, [SRC]!
    pixman_composite_over_8888_0565_process_pixblock_head
    cache_preload 8, 8
.endm

#endif

/*
 * And now the final part. We are using 'generate_composite_function' macro
 * to put all the stuff together. We are specifying the name of the function
 * which we want to get, number of bits per pixel for the source, mask and
 * destination (0 if unused, like mask in this case). Next come some bit
 * flags:
 *   FLAG_DST_READWRITE      - tells that the destination buffer is both read
 *                             and written, for write-only buffer we would use
 *                             FLAG_DST_WRITEONLY flag instead
 *   FLAG_DEINTERLEAVE_32BPP - tells that we prefer to work with planar data
 *                             and separate color channels for 32bpp format.
 * The next things are:
 *  - the number of pixels processed per iteration (8 in this case, because
 *    that's the maximum what can fit into four 64-bit NEON registers).
 *  - prefetch distance, measured in pixel blocks. In this case it is 5 times
 *    by 8 pixels. That would be 40 pixels, or up to 160 bytes. Optimal
 *    prefetch distance can be selected by running some benchmarks.
 *
 * After that we specify some macros, these are 'default_init',
 * 'default_cleanup' here which are empty (but it is possible to have custom
 * init/cleanup macros to be able to save/restore some extra NEON registers
 * like d8-d15 or do anything else) followed by
 * 'pixman_composite_over_8888_0565_process_pixblock_head',
 * 'pixman_composite_over_8888_0565_process_pixblock_tail' and
 * 'pixman_composite_over_8888_0565_process_pixblock_tail_head'
 * which we got implemented above.
 *
 * The last part is the NEON registers allocation scheme.
 */
generate_composite_function \
    pixman_composite_over_8888_0565_asm_neon, 32, 0, 16, \
    FLAG_DST_READWRITE | FLAG_DEINTERLEAVE_32BPP, \
    8, /* number of pixels, processed in a single block */ \
    5, /* prefetch distance */ \
    default_init, \
    default_cleanup, \
    pixman_composite_over_8888_0565_process_pixblock_head, \
    pixman_composite_over_8888_0565_process_pixblock_tail, \
    pixman_composite_over_8888_0565_process_pixblock_tail_head, \
    28, /* dst_w_basereg */ \
    4,  /* dst_r_basereg */ \
    0,  /* src_basereg   */ \
    24  /* mask_basereg  */

/******************************************************************************/

.macro pixman_composite_src_8888_0565_process_pixblock_head
    vshll.u8    q8, d1, #8
    vshll.u8    q14, d2, #8
    vshll.u8    q9, d0, #8
.endm

.macro pixman_composite_src_8888_0565_process_pixblock_tail
    vsri.u16    q14, q8, #5
    vsri.u16    q14, q9, #11
.endm

.macro pixman_composite_src_8888_0565_process_pixblock_tail_head
        vsri.u16    q14, q8, #5
                                    PF add PF_X, PF_X, #8
                                    PF tst PF_CTL, #0xF
    vld4.8      {d0, d1, d2, d3}, [SRC]!
                                    PF addne PF_X, PF_X, #8
                                    PF subne PF_CTL, PF_CTL, #1
        vsri.u16    q14, q9, #11
                                    PF cmp PF_X, ORIG_W
                                    PF pld, [PF_SRC, PF_X, lsl #src_bpp_shift]
    vshll.u8    q8, d1, #8
        vst1.16     {d28, d29}, [DST_W, :128]!
                                    PF subge PF_X, PF_X, ORIG_W
                                    PF subges PF_CTL, PF_CTL, #0x10
    vshll.u8    q14, d2, #8
                                    PF ldrgeb DUMMY, [PF_SRC, SRC_STRIDE, lsl #src_bpp_shift]!
    vshll.u8    q9, d0, #8
.endm

generate_composite_function \
    pixman_composite_src_8888_0565_asm_neon, 32, 0, 16, \
    FLAG_DST_WRITEONLY | FLAG_DEINTERLEAVE_32BPP, \
    8, /* number of pixels, processed in a single block */ \
    10, /* prefetch distance */ \
    default_init, \
    default_cleanup, \
    pixman_composite_src_8888_0565_process_pixblock_head, \
    pixman_composite_src_8888_0565_process_pixblock_tail, \
    pixman_composite_src_8888_0565_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_add_8000_8000_process_pixblock_head
    vqadd.u8    q14, q0, q2
    vqadd.u8    q15, q1, q3
.endm

.macro pixman_composite_add_8000_8000_process_pixblock_tail
.endm

.macro pixman_composite_add_8000_8000_process_pixblock_tail_head
    vld1.8      {d0, d1, d2, d3}, [SRC]!
                                    PF add PF_X, PF_X, #32
                                    PF tst PF_CTL, #0xF
    vld1.8      {d4, d5, d6, d7}, [DST_R, :128]!
                                    PF addne PF_X, PF_X, #32
                                    PF subne PF_CTL, PF_CTL, #1
        vst1.8      {d28, d29, d30, d31}, [DST_W, :128]!
                                    PF cmp PF_X, ORIG_W
                                    PF pld, [PF_SRC, PF_X, lsl #src_bpp_shift]
                                    PF pld, [PF_DST, PF_X, lsl #dst_bpp_shift]
                                    PF subge PF_X, PF_X, ORIG_W
                                    PF subges PF_CTL, PF_CTL, #0x10
    vqadd.u8    q14, q0, q2
                                    PF ldrgeb DUMMY, [PF_SRC, SRC_STRIDE, lsl #src_bpp_shift]!
                                    PF ldrgeb DUMMY, [PF_DST, DST_STRIDE, lsl #dst_bpp_shift]!
    vqadd.u8    q15, q1, q3
.endm

generate_composite_function \
    pixman_composite_add_8000_8000_asm_neon, 8, 0, 8, \
    FLAG_DST_READWRITE, \
    32, /* number of pixels, processed in a single block */ \
    10, /* prefetch distance */ \
    default_init, \
    default_cleanup, \
    pixman_composite_add_8000_8000_process_pixblock_head, \
    pixman_composite_add_8000_8000_process_pixblock_tail, \
    pixman_composite_add_8000_8000_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_over_8888_8888_process_pixblock_head
    vmvn.8      d24, d3  /* get inverted alpha */
    /* do alpha blending */
    vmull.u8    q8, d24, d4
    vmull.u8    q9, d24, d5
    vmull.u8    q10, d24, d6
    vmull.u8    q11, d24, d7
.endm

.macro pixman_composite_over_8888_8888_process_pixblock_tail
    vrshr.u16   q14, q8, #8
    vrshr.u16   q15, q9, #8
    vrshr.u16   q12, q10, #8
    vrshr.u16   q13, q11, #8
    vraddhn.u16 d28, q14, q8
    vraddhn.u16 d29, q15, q9
    vraddhn.u16 d30, q12, q10
    vraddhn.u16 d31, q13, q11
    vqadd.u8    q14, q0, q14
    vqadd.u8    q15, q1, q15
.endm

.macro pixman_composite_over_8888_8888_process_pixblock_tail_head
    vld4.8      {d4, d5, d6, d7}, [DST_R, :128]!
        vrshr.u16   q14, q8, #8
                                    PF add PF_X, PF_X, #8
                                    PF tst PF_CTL, #0xF
        vrshr.u16   q15, q9, #8
        vrshr.u16   q12, q10, #8
        vrshr.u16   q13, q11, #8
                                    PF addne PF_X, PF_X, #8
                                    PF subne PF_CTL, PF_CTL, #1
        vraddhn.u16 d28, q14, q8
        vraddhn.u16 d29, q15, q9
                                    PF cmp PF_X, ORIG_W
        vraddhn.u16 d30, q12, q10
        vraddhn.u16 d31, q13, q11
        vqadd.u8    q14, q0, q14
        vqadd.u8    q15, q1, q15
    vld4.8      {d0, d1, d2, d3}, [SRC]!
                                    PF pld, [PF_SRC, PF_X, lsl #src_bpp_shift]
    vmvn.8      d22, d3
                                    PF pld, [PF_DST, PF_X, lsl #dst_bpp_shift]
        vst4.8      {d28, d29, d30, d31}, [DST_W, :128]!
                                    PF subge PF_X, PF_X, ORIG_W
    vmull.u8    q8, d22, d4
                                    PF subges PF_CTL, PF_CTL, #0x10
    vmull.u8    q9, d22, d5
                                    PF ldrgeb DUMMY, [PF_SRC, SRC_STRIDE, lsl #src_bpp_shift]!
    vmull.u8    q10, d22, d6
                                    PF ldrgeb DUMMY, [PF_DST, DST_STRIDE, lsl #dst_bpp_shift]!
    vmull.u8    q11, d22, d7
.endm

generate_composite_function \
    pixman_composite_over_8888_8888_asm_neon, 32, 0, 32, \
    FLAG_DST_READWRITE | FLAG_DEINTERLEAVE_32BPP, \
    8, /* number of pixels, processed in a single block */ \
    5, /* prefetch distance */ \
    default_init, \
    default_cleanup, \
    pixman_composite_over_8888_8888_process_pixblock_head, \
    pixman_composite_over_8888_8888_process_pixblock_tail, \
    pixman_composite_over_8888_8888_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_over_n_8_0565_process_pixblock_head
    /* in */
    vmull.u8    q0, d24, d8
    vmull.u8    q1, d24, d9
    vmull.u8    q6, d24, d10
    vmull.u8    q7, d24, d11
    vrshr.u16   q10, q0, #8
    vrshr.u16   q11, q1, #8
    vrshr.u16   q12, q6, #8
    vrshr.u16   q13, q7, #8
    vraddhn.u16 d0, q0, q10
    vraddhn.u16 d1, q1, q11
    vraddhn.u16 d2, q6, q12
    vraddhn.u16 d3, q7, q13

    vshrn.u16   d6, q2, #8
    vshrn.u16   d7, q2, #3
    vsli.u16    q2, q2, #5
    vsri.u8     d6, d6, #5
    vmvn.8      d3, d3
    vsri.u8     d7, d7, #6
    vshrn.u16   d30, q2, #2
    /* now do alpha blending */
    vmull.u8    q10, d3, d6
    vmull.u8    q11, d3, d7
    vmull.u8    q12, d3, d30
    vrshr.u16   q13, q10, #8
    vrshr.u16   q3, q11, #8
    vrshr.u16   q15, q12, #8
    vraddhn.u16 d20, q10, q13
    vraddhn.u16 d23, q11, q3
    vraddhn.u16 d22, q12, q15
.endm

.macro pixman_composite_over_n_8_0565_process_pixblock_tail
    vqadd.u8    d16, d2, d20
    vqadd.u8    q9, q0, q11
    /* convert to r5g6b5 */
    vshll.u8    q14, d16, #8
    vshll.u8    q8, d19, #8
    vshll.u8    q9, d18, #8
    vsri.u16    q14, q8, #5
    vsri.u16    q14, q9, #11
.endm

/* TODO: expand macros and do better instructions scheduling */
.macro pixman_composite_over_n_8_0565_process_pixblock_tail_head
    pixman_composite_over_n_8_0565_process_pixblock_tail
    vst1.16     {d28, d29}, [DST_W, :128]!
    vld1.16     {d4, d5}, [DST_R, :128]!
    vld1.8      {d24}, [MASK]!
    cache_preload 8, 8
    pixman_composite_over_n_8_0565_process_pixblock_head
.endm

/*
 * This function needs a special initialization of solid mask.
 * Solid source pixel data is fetched from stack at ARGS_STACK_OFFSET
 * offset, split into color components and replicated in d8-d11
 * registers. Additionally, this function needs all the NEON registers,
 * so it has to save d8-d15 registers which are callee saved according
 * to ABI. These registers are restored from 'cleanup' macro. All the
 * other NEON registers are caller saved, so can be clobbered freely
 * without introducing any problems.
 */
.macro pixman_composite_over_n_8_0565_init
    add         DUMMY, sp, #ARGS_STACK_OFFSET
    vpush       {d8-d15}
    vld1.32     {d11[0]}, [DUMMY]
    vdup.8      d8, d11[0]
    vdup.8      d9, d11[1]
    vdup.8      d10, d11[2]
    vdup.8      d11, d11[3]
.endm

.macro pixman_composite_over_n_8_0565_cleanup
    vpop        {d8-d15}
.endm

generate_composite_function \
    pixman_composite_over_n_8_0565_asm_neon, 0, 8, 16, \
    FLAG_DST_READWRITE, \
    8, /* number of pixels, processed in a single block */ \
    5, /* prefetch distance */ \
    pixman_composite_over_n_8_0565_init, \
    pixman_composite_over_n_8_0565_cleanup, \
    pixman_composite_over_n_8_0565_process_pixblock_head, \
    pixman_composite_over_n_8_0565_process_pixblock_tail, \
    pixman_composite_over_n_8_0565_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_src_0565_0565_process_pixblock_head
.endm

.macro pixman_composite_src_0565_0565_process_pixblock_tail
.endm

.macro pixman_composite_src_0565_0565_process_pixblock_tail_head
    vst1.16 {d0, d1, d2, d3}, [DST_W, :128]!
    vld1.16 {d0, d1, d2, d3}, [SRC]!
    cache_preload 16, 16
.endm

generate_composite_function \
    pixman_composite_src_0565_0565_asm_neon, 16, 0, 16, \
    FLAG_DST_WRITEONLY, \
    16, /* number of pixels, processed in a single block */ \
    10, /* prefetch distance */ \
    default_init, \
    default_cleanup, \
    pixman_composite_src_0565_0565_process_pixblock_head, \
    pixman_composite_src_0565_0565_process_pixblock_tail, \
    pixman_composite_src_0565_0565_process_pixblock_tail_head, \
    0, /* dst_w_basereg */ \
    0, /* dst_r_basereg */ \
    0, /* src_basereg   */ \
    0  /* mask_basereg  */

/******************************************************************************/

.macro pixman_composite_src_n_8_process_pixblock_head
.endm

.macro pixman_composite_src_n_8_process_pixblock_tail
.endm

.macro pixman_composite_src_n_8_process_pixblock_tail_head
    vst1.8  {d0, d1, d2, d3}, [DST_W, :128]!
.endm

.macro pixman_composite_src_n_8_init
    add         DUMMY, sp, #ARGS_STACK_OFFSET
    vld1.32     {d0[0]}, [DUMMY]
    vsli.u64    d0, d0, #8
    vsli.u64    d0, d0, #16
    vsli.u64    d0, d0, #32
    vmov        d1, d0
    vmov        q1, q0
.endm

.macro pixman_composite_src_n_8_cleanup
.endm

generate_composite_function \
    pixman_composite_src_n_8_asm_neon, 0, 0, 8, \
    FLAG_DST_WRITEONLY, \
    32, /* number of pixels, processed in a single block */ \
    0,  /* prefetch distance */ \
    pixman_composite_src_n_8_init, \
    pixman_composite_src_n_8_cleanup, \
    pixman_composite_src_n_8_process_pixblock_head, \
    pixman_composite_src_n_8_process_pixblock_tail, \
    pixman_composite_src_n_8_process_pixblock_tail_head, \
    0, /* dst_w_basereg */ \
    0, /* dst_r_basereg */ \
    0, /* src_basereg   */ \
    0  /* mask_basereg  */

/******************************************************************************/

.macro pixman_composite_src_n_0565_process_pixblock_head
.endm

.macro pixman_composite_src_n_0565_process_pixblock_tail
.endm

.macro pixman_composite_src_n_0565_process_pixblock_tail_head
    vst1.16 {d0, d1, d2, d3}, [DST_W, :128]!
.endm

.macro pixman_composite_src_n_0565_init
    add         DUMMY, sp, #ARGS_STACK_OFFSET
    vld1.32     {d0[0]}, [DUMMY]
    vsli.u64    d0, d0, #16
    vsli.u64    d0, d0, #32
    vmov        d1, d0
    vmov        q1, q0
.endm

.macro pixman_composite_src_n_0565_cleanup
.endm

generate_composite_function \
    pixman_composite_src_n_0565_asm_neon, 0, 0, 16, \
    FLAG_DST_WRITEONLY, \
    16, /* number of pixels, processed in a single block */ \
    0,  /* prefetch distance */ \
    pixman_composite_src_n_0565_init, \
    pixman_composite_src_n_0565_cleanup, \
    pixman_composite_src_n_0565_process_pixblock_head, \
    pixman_composite_src_n_0565_process_pixblock_tail, \
    pixman_composite_src_n_0565_process_pixblock_tail_head, \
    0, /* dst_w_basereg */ \
    0, /* dst_r_basereg */ \
    0, /* src_basereg   */ \
    0  /* mask_basereg  */

/******************************************************************************/

.macro pixman_composite_src_n_8888_process_pixblock_head
.endm

.macro pixman_composite_src_n_8888_process_pixblock_tail
.endm

.macro pixman_composite_src_n_8888_process_pixblock_tail_head
    vst1.32 {d0, d1, d2, d3}, [DST_W, :128]!
.endm

.macro pixman_composite_src_n_8888_init
    add         DUMMY, sp, #ARGS_STACK_OFFSET
    vld1.32     {d0[0]}, [DUMMY]
    vsli.u64    d0, d0, #32
    vmov        d1, d0
    vmov        q1, q0
.endm

.macro pixman_composite_src_n_8888_cleanup
.endm

generate_composite_function \
    pixman_composite_src_n_8888_asm_neon, 0, 0, 32, \
    FLAG_DST_WRITEONLY, \
    8, /* number of pixels, processed in a single block */ \
    0, /* prefetch distance */ \
    pixman_composite_src_n_8888_init, \
    pixman_composite_src_n_8888_cleanup, \
    pixman_composite_src_n_8888_process_pixblock_head, \
    pixman_composite_src_n_8888_process_pixblock_tail, \
    pixman_composite_src_n_8888_process_pixblock_tail_head, \
    0, /* dst_w_basereg */ \
    0, /* dst_r_basereg */ \
    0, /* src_basereg   */ \
    0  /* mask_basereg  */

/******************************************************************************/

.macro pixman_composite_src_8888_8888_process_pixblock_head
.endm

.macro pixman_composite_src_8888_8888_process_pixblock_tail
.endm

.macro pixman_composite_src_8888_8888_process_pixblock_tail_head
    vst1.32 {d0, d1, d2, d3}, [DST_W, :128]!
    vld1.32 {d0, d1, d2, d3}, [SRC]!
    cache_preload 8, 8
.endm

generate_composite_function \
    pixman_composite_src_8888_8888_asm_neon, 32, 0, 32, \
    FLAG_DST_WRITEONLY, \
    8, /* number of pixels, processed in a single block */ \
    10, /* prefetch distance */ \
    default_init, \
    default_cleanup, \
    pixman_composite_src_8888_8888_process_pixblock_head, \
    pixman_composite_src_8888_8888_process_pixblock_tail, \
    pixman_composite_src_8888_8888_process_pixblock_tail_head, \
    0, /* dst_w_basereg */ \
    0, /* dst_r_basereg */ \
    0, /* src_basereg   */ \
    0  /* mask_basereg  */

/******************************************************************************/

.macro pixman_composite_over_n_8_8888_process_pixblock_head
    /* expecting deinterleaved source data in {d8, d9, d10, d11} */
    /* d8 - blue, d9 - green, d10 - red, d11 - alpha */
    /* and destination data in {d4, d5, d6, d7} */
    /* mask is in d24 (d25, d26, d27 are unused) */

    /* in */
    vmull.u8    q0, d24, d8
    vmull.u8    q1, d24, d9
    vmull.u8    q6, d24, d10
    vmull.u8    q7, d24, d11
    vrshr.u16   q10, q0, #8
    vrshr.u16   q11, q1, #8
    vrshr.u16   q12, q6, #8
    vrshr.u16   q13, q7, #8
    vraddhn.u16 d0, q0, q10
    vraddhn.u16 d1, q1, q11
    vraddhn.u16 d2, q6, q12
    vraddhn.u16 d3, q7, q13
    vmvn.8      d24, d3  /* get inverted alpha */
    /* source:      d0 - blue, d1 - green, d2 - red, d3 - alpha */
    /* destination: d4 - blue, d5 - green, d6 - red, d7 - alpha */
    /* now do alpha blending */
    vmull.u8    q8, d24, d4
    vmull.u8    q9, d24, d5
    vmull.u8    q10, d24, d6
    vmull.u8    q11, d24, d7
.endm

.macro pixman_composite_over_n_8_8888_process_pixblock_tail
    vrshr.u16   q14, q8, #8
    vrshr.u16   q15, q9, #8
    vrshr.u16   q12, q10, #8
    vrshr.u16   q13, q11, #8
    vraddhn.u16 d28, q14, q8
    vraddhn.u16 d29, q15, q9
    vraddhn.u16 d30, q12, q10
    vraddhn.u16 d31, q13, q11
    vqadd.u8    q14, q0, q14
    vqadd.u8    q15, q1, q15
.endm

/* TODO: expand macros and do better instructions scheduling */
.macro pixman_composite_over_n_8_8888_process_pixblock_tail_head
    pixman_composite_over_n_8_8888_process_pixblock_tail
    vst4.8      {d28, d29, d30, d31}, [DST_W, :128]!
    vld4.8      {d4, d5, d6, d7}, [DST_R, :128]!
    vld1.8      {d24}, [MASK]!
    cache_preload 8, 8
    pixman_composite_over_n_8_8888_process_pixblock_head
.endm

.macro pixman_composite_over_n_8_8888_init
    add         DUMMY, sp, #ARGS_STACK_OFFSET
    vpush       {d8-d15}
    vld1.32     {d11[0]}, [DUMMY]
    vdup.8      d8, d11[0]
    vdup.8      d9, d11[1]
    vdup.8      d10, d11[2]
    vdup.8      d11, d11[3]
.endm

.macro pixman_composite_over_n_8_8888_cleanup
    vpop        {d8-d15}
.endm

generate_composite_function \
    pixman_composite_over_n_8_8888_asm_neon, 0, 8, 32, \
    FLAG_DST_READWRITE | FLAG_DEINTERLEAVE_32BPP, \
    8, /* number of pixels, processed in a single block */ \
    5, /* prefetch distance */ \
    pixman_composite_over_n_8_8888_init, \
    pixman_composite_over_n_8_8888_cleanup, \
    pixman_composite_over_n_8_8888_process_pixblock_head, \
    pixman_composite_over_n_8_8888_process_pixblock_tail, \
    pixman_composite_over_n_8_8888_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_add_n_8_8_process_pixblock_head
    /* expecting source data in {d8, d9, d10, d11} */
    /* d8 - blue, d9 - green, d10 - red, d11 - alpha */
    /* and destination data in {d4, d5, d6, d7} */
    /* mask is in d24, d25, d26, d27 */
    vmull.u8    q0, d24, d11
    vmull.u8    q1, d25, d11
    vmull.u8    q6, d26, d11
    vmull.u8    q7, d27, d11
    vrshr.u16   q10, q0, #8
    vrshr.u16   q11, q1, #8
    vrshr.u16   q12, q6, #8
    vrshr.u16   q13, q7, #8
    vraddhn.u16 d0, q0, q10
    vraddhn.u16 d1, q1, q11
    vraddhn.u16 d2, q6, q12
    vraddhn.u16 d3, q7, q13
    vqadd.u8    q14, q0, q2
    vqadd.u8    q15, q1, q3
.endm

.macro pixman_composite_add_n_8_8_process_pixblock_tail
.endm

/* TODO: expand macros and do better instructions scheduling */
.macro pixman_composite_add_n_8_8_process_pixblock_tail_head
    pixman_composite_add_n_8_8_process_pixblock_tail
    vst1.8      {d28, d29, d30, d31}, [DST_W, :128]!
    vld1.8      {d4, d5, d6, d7}, [DST_R, :128]!
    vld1.8      {d24, d25, d26, d27}, [MASK]!
    cache_preload 32, 32
    pixman_composite_add_n_8_8_process_pixblock_head
.endm

.macro pixman_composite_add_n_8_8_init
    add         DUMMY, sp, #ARGS_STACK_OFFSET
    vpush       {d8-d15}
    vld1.32     {d11[0]}, [DUMMY]
    vdup.8      d11, d11[3]
.endm

.macro pixman_composite_add_n_8_8_cleanup
    vpop        {d8-d15}
.endm

generate_composite_function \
    pixman_composite_add_n_8_8_asm_neon, 0, 8, 8, \
    FLAG_DST_READWRITE, \
    32, /* number of pixels, processed in a single block */ \
    5, /* prefetch distance */ \
    pixman_composite_add_n_8_8_init, \
    pixman_composite_add_n_8_8_cleanup, \
    pixman_composite_add_n_8_8_process_pixblock_head, \
    pixman_composite_add_n_8_8_process_pixblock_tail, \
    pixman_composite_add_n_8_8_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_add_8_8_8_process_pixblock_head
    /* expecting source data in {d0, d1, d2, d3} */
    /* destination data in {d4, d5, d6, d7} */
    /* mask in {d24, d25, d26, d27} */
    vmull.u8    q8, d24, d0
    vmull.u8    q9, d25, d1
    vmull.u8    q10, d26, d2
    vmull.u8    q11, d27, d3
    vrshr.u16   q0, q8, #8
    vrshr.u16   q1, q9, #8
    vrshr.u16   q12, q10, #8
    vrshr.u16   q13, q11, #8
    vraddhn.u16 d0, q0, q8
    vraddhn.u16 d1, q1, q9
    vraddhn.u16 d2, q12, q10
    vraddhn.u16 d3, q13, q11
    vqadd.u8    q14, q0, q2
    vqadd.u8    q15, q1, q3
.endm

.macro pixman_composite_add_8_8_8_process_pixblock_tail
.endm

/* TODO: expand macros and do better instructions scheduling */
.macro pixman_composite_add_8_8_8_process_pixblock_tail_head
    pixman_composite_add_8_8_8_process_pixblock_tail
    vst1.8      {d28, d29, d30, d31}, [DST_W, :128]!
    vld1.8      {d4, d5, d6, d7}, [DST_R, :128]!
    vld1.8      {d24, d25, d26, d27}, [MASK]!
    vld1.8      {d0, d1, d2, d3}, [SRC]!
    cache_preload 32, 32
    pixman_composite_add_8_8_8_process_pixblock_head
.endm

.macro pixman_composite_add_8_8_8_init
.endm

.macro pixman_composite_add_8_8_8_cleanup
.endm

generate_composite_function \
    pixman_composite_add_8_8_8_asm_neon, 8, 8, 8, \
    FLAG_DST_READWRITE, \
    32, /* number of pixels, processed in a single block */ \
    5, /* prefetch distance */ \
    pixman_composite_add_8_8_8_init, \
    pixman_composite_add_8_8_8_cleanup, \
    pixman_composite_add_8_8_8_process_pixblock_head, \
    pixman_composite_add_8_8_8_process_pixblock_tail, \
    pixman_composite_add_8_8_8_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_over_8888_n_8888_process_pixblock_head
    /* expecting source data in {d0, d1, d2, d3} */
    /* destination data in {d4, d5, d6, d7} */
    /* solid mask is in d15 */

    /* 'in' */
    vmull.u8    q8, d15, d3
    vmull.u8    q6, d15, d2
    vmull.u8    q5, d15, d1
    vmull.u8    q4, d15, d0
    vrshr.u16   q13, q8, #8
    vrshr.u16   q12, q6, #8
    vrshr.u16   q11, q5, #8
    vrshr.u16   q10, q4, #8
    vraddhn.u16 d3, q8, q13
    vraddhn.u16 d2, q6, q12
    vraddhn.u16 d1, q5, q11
    vraddhn.u16 d0, q4, q10
    vmvn.8      d24, d3  /* get inverted alpha */
    /* now do alpha blending */
    vmull.u8    q8, d24, d4
    vmull.u8    q9, d24, d5
    vmull.u8    q10, d24, d6
    vmull.u8    q11, d24, d7
.endm

.macro pixman_composite_over_8888_n_8888_process_pixblock_tail
    vrshr.u16   q14, q8, #8
    vrshr.u16   q15, q9, #8
    vrshr.u16   q12, q10, #8
    vrshr.u16   q13, q11, #8
    vraddhn.u16 d28, q14, q8
    vraddhn.u16 d29, q15, q9
    vraddhn.u16 d30, q12, q10
    vraddhn.u16 d31, q13, q11
    vqadd.u8    q14, q0, q14
    vqadd.u8    q15, q1, q15
.endm

/* TODO: expand macros and do better instructions scheduling */
.macro pixman_composite_over_8888_n_8888_process_pixblock_tail_head
    vld4.8     {d4, d5, d6, d7}, [DST_R, :128]!
    pixman_composite_over_8888_n_8888_process_pixblock_tail
    vld4.8     {d0, d1, d2, d3}, [SRC]!
    cache_preload 8, 8
    pixman_composite_over_8888_n_8888_process_pixblock_head
    vst4.8     {d28, d29, d30, d31}, [DST_W, :128]!
.endm

.macro pixman_composite_over_8888_n_8888_init
    add         DUMMY, sp, #48
    vpush       {d8-d15}
    vld1.32     {d15[0]}, [DUMMY]
    vdup.8      d15, d15[3]
.endm

.macro pixman_composite_over_8888_n_8888_cleanup
    vpop        {d8-d15}
.endm

generate_composite_function \
    pixman_composite_over_8888_n_8888_asm_neon, 32, 0, 32, \
    FLAG_DST_READWRITE | FLAG_DEINTERLEAVE_32BPP, \
    8, /* number of pixels, processed in a single block */ \
    5, /* prefetch distance */ \
    pixman_composite_over_8888_n_8888_init, \
    pixman_composite_over_8888_n_8888_cleanup, \
    pixman_composite_over_8888_n_8888_process_pixblock_head, \
    pixman_composite_over_8888_n_8888_process_pixblock_tail, \
    pixman_composite_over_8888_n_8888_process_pixblock_tail_head

/******************************************************************************/

.macro pixman_composite_src_0888_0888_process_pixblock_head
.endm

.macro pixman_composite_src_0888_0888_process_pixblock_tail
.endm

.macro pixman_composite_src_0888_0888_process_pixblock_tail_head
    vst3.8 {d0, d1, d2}, [DST_W]!
    vld3.8 {d0, d1, d2}, [SRC]!
    cache_preload 8, 8
.endm

generate_composite_function \
    pixman_composite_src_0888_0888_asm_neon, 24, 0, 24, \
    FLAG_DST_WRITEONLY, \
    8, /* number of pixels, processed in a single block */ \
    10, /* prefetch distance */ \
    default_init, \
    default_cleanup, \
    pixman_composite_src_0888_0888_process_pixblock_head, \
    pixman_composite_src_0888_0888_process_pixblock_tail, \
    pixman_composite_src_0888_0888_process_pixblock_tail_head, \
    0, /* dst_w_basereg */ \
    0, /* dst_r_basereg */ \
    0, /* src_basereg   */ \
    0  /* mask_basereg  */