Commit 2dfe06056413d4c919f73ac0d936cef25e2144a9

Ben Avison 2019-10-24T21:17:19

ARM: NEON assembly optimization for function BlitRGBtoRGBPixelAlpha

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diff --git a/src/video/SDL_blit_A.c b/src/video/SDL_blit_A.c
index a1d087d..53a71f3 100644
--- a/src/video/SDL_blit_A.c
+++ b/src/video/SDL_blit_A.c
@@ -421,6 +421,23 @@ BlitRGBtoRGBPixelAlphaARMSIMD(SDL_BlitInfo * info)
 }
 #endif
 
+#if SDL_ARM_NEON_BLITTERS
+void BlitRGBtoRGBPixelAlphaARMNEONAsm(int32_t w, int32_t h, uint32_t *dst, int32_t dst_stride, uint32_t *src, int32_t src_stride);
+
+static void
+BlitRGBtoRGBPixelAlphaARMNEON(SDL_BlitInfo * info)
+{
+	int32_t width = info->dst_w;
+	int32_t height = info->dst_h;
+	uint32_t *dstp = (uint32_t *)info->dst;
+	int32_t dststride = width + (info->dst_skip >> 2);
+	uint32_t *srcp = (uint32_t *)info->src;
+	int32_t srcstride = width + (info->src_skip >> 2);
+
+	BlitRGBtoRGBPixelAlphaARMNEONAsm(width, height, dstp, dststride, srcp, srcstride);
+}
+#endif
+
 /* fast RGB888->(A)RGB888 blending with surface alpha=128 special case */
 static void
 BlitRGBtoRGBSurfaceAlpha128(SDL_BlitInfo * info)
@@ -1356,6 +1373,10 @@ SDL_CalculateBlitA(SDL_Surface * surface)
                 }
 #endif /* __MMX__ || __3dNOW__ */
                 if (sf->Amask == 0xff000000) {
+#if SDL_ARM_NEON_BLITTERS
+                    if (SDL_HasNEON())
+                        return BlitRGBtoRGBPixelAlphaARMNEON;
+#endif
 #if SDL_ARM_SIMD_BLITTERS
                     if (SDL_HasARMSIMD())
                         return BlitRGBtoRGBPixelAlphaARMSIMD;
diff --git a/src/video/arm/pixman-arm-neon-asm.S b/src/video/arm/pixman-arm-neon-asm.S
new file mode 100644
index 0000000..72fd3a2
--- /dev/null
+++ b/src/video/arm/pixman-arm-neon-asm.S
@@ -0,0 +1,159 @@
+/*
+ * Copyright © 2009 Nokia Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Author:  Siarhei Siamashka (siarhei.siamashka@nokia.com)
+ */
+
+/*
+ * Copyright (c) 2018 RISC OS Open Ltd
+ *
+ * This software is provided 'as-is', without any express or implied
+ * warranty.  In no event will the authors be held liable for any damages
+ * arising from the use of this software.
+ *
+ * Permission is granted to anyone to use this software for any purpose,
+ * including commercial applications, and to alter it and redistribute it
+ * freely, subject to the following restrictions:
+ *
+ * 1. The origin of this software must not be misrepresented; you must not
+ *    claim that you wrote the original software. If you use this software
+ *    in a product, an acknowledgment in the product documentation would be
+ *    appreciated but is not required.
+ * 2. Altered source versions must be plainly marked as such, and must not be
+ *    misrepresented as being the original software.
+ * 3. This notice may not be removed or altered from any source distribution.
+ */
+
+/* Prevent the stack from becoming executable for no reason... */
+#if defined(__linux__) && defined(__ELF__)
+.section .note.GNU-stack,"",%progbits
+#endif
+
+    .text
+    .fpu neon
+    .arch armv7a
+    .object_arch armv4
+    .eabi_attribute 10, 0 /* suppress Tag_FP_arch */
+    .eabi_attribute 12, 0 /* suppress Tag_Advanced_SIMD_arch */
+    .arm
+    .altmacro
+    .p2align 2
+
+#include "pixman-arm-asm.h"
+#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
+
+/******************************************************************************/
+
+.macro RGBtoRGBPixelAlpha_process_pixblock_head
+    vmvn        d30, d3  /* get inverted source alpha */
+    vmov        d31, d7  /* dest alpha is always unchanged */
+    vmull.u8    q14, d0, d3
+    vmlal.u8    q14, d4, d30
+    vmull.u8    q0, d1, d3
+    vmlal.u8    q0, d5, d30
+    vmull.u8    q1, d2, d3
+    vmlal.u8    q1, d6, d30
+    vrshr.u16   q2, q14, #8
+    vrshr.u16   q3, q0, #8
+    vraddhn.u16 d28, q14, q2
+    vrshr.u16   q2, q1, #8
+    vraddhn.u16 d29, q0, q3
+    vraddhn.u16 d30, q1, q2
+.endm
+
+.macro RGBtoRGBPixelAlpha_process_pixblock_tail
+    /* nothing */
+.endm
+
+.macro RGBtoRGBPixelAlpha_process_pixblock_tail_head
+    vld4.8      {d0-d3}, [SRC]!
+                                    PF add PF_X, PF_X, #8
+        vst4.8      {d28-d31}, [DST_W :128]!
+                                    PF tst PF_CTL, #0xF
+    vld4.8      {d4-d7}, [DST_R :128]!
+                                    PF addne PF_X, PF_X, #8
+    vmvn        d30, d3  /* get inverted source alpha */
+    vmov        d31, d7  /* dest alpha is always unchanged */
+    vmull.u8    q14, d0, d3
+                                    PF subne PF_CTL, PF_CTL, #1
+    vmlal.u8    q14, d4, d30
+                                    PF cmp PF_X, ORIG_W
+    vmull.u8    q0, d1, d3
+                                    PF pld, [PF_SRC, PF_X, lsl #src_bpp_shift]
+    vmlal.u8    q0, d5, d30
+                                    PF pld, [PF_DST, PF_X, lsl #dst_bpp_shift]
+    vmull.u8    q1, d2, d3
+                                    PF subge PF_X, PF_X, ORIG_W
+    vmlal.u8    q1, d6, d30
+                                    PF subges PF_CTL, PF_CTL, #0x10
+    vrshr.u16   q2, q14, #8
+                                    PF ldrgeb DUMMY, [PF_SRC, SRC_STRIDE, lsl #src_bpp_shift]!
+    vrshr.u16   q3, q0, #8
+                                    PF ldrgeb DUMMY, [PF_DST, DST_STRIDE, lsl #dst_bpp_shift]!
+    vraddhn.u16 d28, q14, q2
+    vrshr.u16   q2, q1, #8
+    vraddhn.u16 d29, q0, q3
+    vraddhn.u16 d30, q1, q2
+.endm
+
+generate_composite_function \
+    BlitRGBtoRGBPixelAlphaARMNEONAsm, 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, \
+    RGBtoRGBPixelAlpha_process_pixblock_head, \
+    RGBtoRGBPixelAlpha_process_pixblock_tail, \
+    RGBtoRGBPixelAlpha_process_pixblock_tail_head
diff --git a/src/video/arm/pixman-arm-neon-asm.h b/src/video/arm/pixman-arm-neon-asm.h
new file mode 100644
index 0000000..bdcf6a9
--- /dev/null
+++ b/src/video/arm/pixman-arm-neon-asm.h
@@ -0,0 +1,1184 @@
+/*
+ * Copyright © 2009 Nokia Corporation
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER
+ * DEALINGS IN THE SOFTWARE.
+ *
+ * Author:  Siarhei Siamashka (siarhei.siamashka@nokia.com)
+ */
+
+/*
+ * This file contains a macro ('generate_composite_function') which can
+ * construct 2D image processing functions, based on a common template.
+ * Any combinations of source, destination and mask images with 8bpp,
+ * 16bpp, 24bpp, 32bpp color formats are supported.
+ *
+ * This macro takes care of:
+ *  - handling of leading and trailing unaligned pixels
+ *  - doing most of the work related to L2 cache preload
+ *  - encourages the use of software pipelining for better instructions
+ *    scheduling
+ *
+ * The user of this macro has to provide some configuration parameters
+ * (bit depths for the images, prefetch distance, etc.) and a set of
+ * macros, which should implement basic code chunks responsible for
+ * pixels processing. See 'pixman-arm-neon-asm.S' file for the usage
+ * examples.
+ *
+ * TODO:
+ *  - try overlapped pixel method (from Ian Rickards) when processing
+ *    exactly two blocks of pixels
+ *  - maybe add an option to do reverse scanline processing
+ */
+
+/*
+ * Bit flags for 'generate_composite_function' macro which are used
+ * to tune generated functions behavior.
+ */
+.set FLAG_DST_WRITEONLY,       0
+.set FLAG_DST_READWRITE,       1
+.set FLAG_DEINTERLEAVE_32BPP,  2
+
+/*
+ * Offset in stack where mask and source pointer/stride can be accessed
+ * from 'init' macro. This is useful for doing special handling for solid mask.
+ */
+.set ARGS_STACK_OFFSET,        40
+
+/*
+ * Constants for selecting preferable prefetch type.
+ */
+.set PREFETCH_TYPE_NONE,       0 /* No prefetch at all */
+.set PREFETCH_TYPE_SIMPLE,     1 /* A simple, fixed-distance-ahead prefetch */
+.set PREFETCH_TYPE_ADVANCED,   2 /* Advanced fine-grained prefetch */
+
+/*
+ * Definitions of supplementary pixld/pixst macros (for partial load/store of
+ * pixel data).
+ */
+
+.macro pixldst1 op, elem_size, reg1, mem_operand, abits
+.if abits > 0
+    op&.&elem_size {d&reg1}, [&mem_operand&, :&abits&]!
+.else
+    op&.&elem_size {d&reg1}, [&mem_operand&]!
+.endif
+.endm
+
+.macro pixldst2 op, elem_size, reg1, reg2, mem_operand, abits
+.if abits > 0
+    op&.&elem_size {d&reg1, d&reg2}, [&mem_operand&, :&abits&]!
+.else
+    op&.&elem_size {d&reg1, d&reg2}, [&mem_operand&]!
+.endif
+.endm
+
+.macro pixldst4 op, elem_size, reg1, reg2, reg3, reg4, mem_operand, abits
+.if abits > 0
+    op&.&elem_size {d&reg1, d&reg2, d&reg3, d&reg4}, [&mem_operand&, :&abits&]!
+.else
+    op&.&elem_size {d&reg1, d&reg2, d&reg3, d&reg4}, [&mem_operand&]!
+.endif
+.endm
+
+.macro pixldst0 op, elem_size, reg1, idx, mem_operand, abits
+    op&.&elem_size {d&reg1[idx]}, [&mem_operand&]!
+.endm
+
+.macro pixldst3 op, elem_size, reg1, reg2, reg3, mem_operand
+    op&.&elem_size {d&reg1, d&reg2, d&reg3}, [&mem_operand&]!
+.endm
+
+.macro pixldst30 op, elem_size, reg1, reg2, reg3, idx, mem_operand
+    op&.&elem_size {d&reg1[idx], d&reg2[idx], d&reg3[idx]}, [&mem_operand&]!
+.endm
+
+.macro pixldst numbytes, op, elem_size, basereg, mem_operand, abits
+.if numbytes == 32
+    pixldst4 op, elem_size, %(basereg+4), %(basereg+5), \
+                              %(basereg+6), %(basereg+7), mem_operand, abits
+.elseif numbytes == 16
+    pixldst2 op, elem_size, %(basereg+2), %(basereg+3), mem_operand, abits
+.elseif numbytes == 8
+    pixldst1 op, elem_size, %(basereg+1), mem_operand, abits
+.elseif numbytes == 4
+    .if !RESPECT_STRICT_ALIGNMENT || (elem_size == 32)
+        pixldst0 op, 32, %(basereg+0), 1, mem_operand, abits
+    .elseif elem_size == 16
+        pixldst0 op, 16, %(basereg+0), 2, mem_operand, abits
+        pixldst0 op, 16, %(basereg+0), 3, mem_operand, abits
+    .else
+        pixldst0 op, 8, %(basereg+0), 4, mem_operand, abits
+        pixldst0 op, 8, %(basereg+0), 5, mem_operand, abits
+        pixldst0 op, 8, %(basereg+0), 6, mem_operand, abits
+        pixldst0 op, 8, %(basereg+0), 7, mem_operand, abits
+    .endif
+.elseif numbytes == 2
+    .if !RESPECT_STRICT_ALIGNMENT || (elem_size == 16)
+        pixldst0 op, 16, %(basereg+0), 1, mem_operand, abits
+    .else
+        pixldst0 op, 8, %(basereg+0), 2, mem_operand, abits
+        pixldst0 op, 8, %(basereg+0), 3, mem_operand, abits
+    .endif
+.elseif numbytes == 1
+    pixldst0 op, 8, %(basereg+0), 1, mem_operand, abits
+.else
+    .error "unsupported size: numbytes"
+.endif
+.endm
+
+.macro pixld numpix, bpp, basereg, mem_operand, abits=0
+.if bpp > 0
+.if (bpp == 32) && (numpix == 8) && (DEINTERLEAVE_32BPP_ENABLED != 0)
+    pixldst4 vld4, 8, %(basereg+4), %(basereg+5), \
+                      %(basereg+6), %(basereg+7), mem_operand, abits
+.elseif (bpp == 24) && (numpix == 8)
+    pixldst3 vld3, 8, %(basereg+3), %(basereg+4), %(basereg+5), mem_operand
+.elseif (bpp == 24) && (numpix == 4)
+    pixldst30 vld3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 4, mem_operand
+    pixldst30 vld3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 5, mem_operand
+    pixldst30 vld3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 6, mem_operand
+    pixldst30 vld3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 7, mem_operand
+.elseif (bpp == 24) && (numpix == 2)
+    pixldst30 vld3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 2, mem_operand
+    pixldst30 vld3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 3, mem_operand
+.elseif (bpp == 24) && (numpix == 1)
+    pixldst30 vld3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 1, mem_operand
+.else
+    pixldst %(numpix * bpp / 8), vld1, %(bpp), basereg, mem_operand, abits
+.endif
+.endif
+.endm
+
+.macro pixst numpix, bpp, basereg, mem_operand, abits=0
+.if bpp > 0
+.if (bpp == 32) && (numpix == 8) && (DEINTERLEAVE_32BPP_ENABLED != 0)
+    pixldst4 vst4, 8, %(basereg+4), %(basereg+5), \
+                      %(basereg+6), %(basereg+7), mem_operand, abits
+.elseif (bpp == 24) && (numpix == 8)
+    pixldst3 vst3, 8, %(basereg+3), %(basereg+4), %(basereg+5), mem_operand
+.elseif (bpp == 24) && (numpix == 4)
+    pixldst30 vst3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 4, mem_operand
+    pixldst30 vst3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 5, mem_operand
+    pixldst30 vst3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 6, mem_operand
+    pixldst30 vst3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 7, mem_operand
+.elseif (bpp == 24) && (numpix == 2)
+    pixldst30 vst3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 2, mem_operand
+    pixldst30 vst3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 3, mem_operand
+.elseif (bpp == 24) && (numpix == 1)
+    pixldst30 vst3, 8, %(basereg+0), %(basereg+1), %(basereg+2), 1, mem_operand
+.else
+    pixldst %(numpix * bpp / 8), vst1, %(bpp), basereg, mem_operand, abits
+.endif
+.endif
+.endm
+
+.macro pixld_a numpix, bpp, basereg, mem_operand
+.if (bpp * numpix) <= 128
+    pixld numpix, bpp, basereg, mem_operand, %(bpp * numpix)
+.else
+    pixld numpix, bpp, basereg, mem_operand, 128
+.endif
+.endm
+
+.macro pixst_a numpix, bpp, basereg, mem_operand
+.if (bpp * numpix) <= 128
+    pixst numpix, bpp, basereg, mem_operand, %(bpp * numpix)
+.else
+    pixst numpix, bpp, basereg, mem_operand, 128
+.endif
+.endm
+
+/*
+ * Pixel fetcher for nearest scaling (needs TMP1, TMP2, VX, UNIT_X register
+ * aliases to be defined)
+ */
+.macro pixld1_s elem_size, reg1, mem_operand
+.if elem_size == 16
+    mov     TMP1, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP1, mem_operand, TMP1, asl #1
+    mov     TMP2, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP2, mem_operand, TMP2, asl #1
+    vld1.16 {d&reg1&[0]}, [TMP1, :16]
+    mov     TMP1, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP1, mem_operand, TMP1, asl #1
+    vld1.16 {d&reg1&[1]}, [TMP2, :16]
+    mov     TMP2, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP2, mem_operand, TMP2, asl #1
+    vld1.16 {d&reg1&[2]}, [TMP1, :16]
+    vld1.16 {d&reg1&[3]}, [TMP2, :16]
+.elseif elem_size == 32
+    mov     TMP1, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP1, mem_operand, TMP1, asl #2
+    mov     TMP2, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP2, mem_operand, TMP2, asl #2
+    vld1.32 {d&reg1&[0]}, [TMP1, :32]
+    vld1.32 {d&reg1&[1]}, [TMP2, :32]
+.else
+    .error "unsupported"
+.endif
+.endm
+
+.macro pixld2_s elem_size, reg1, reg2, mem_operand
+.if 0 /* elem_size == 32 */
+    mov     TMP1, VX, asr #16
+    add     VX, VX, UNIT_X, asl #1
+    add     TMP1, mem_operand, TMP1, asl #2
+    mov     TMP2, VX, asr #16
+    sub     VX, VX, UNIT_X
+    add     TMP2, mem_operand, TMP2, asl #2
+    vld1.32 {d&reg1&[0]}, [TMP1, :32]
+    mov     TMP1, VX, asr #16
+    add     VX, VX, UNIT_X, asl #1
+    add     TMP1, mem_operand, TMP1, asl #2
+    vld1.32 {d&reg2&[0]}, [TMP2, :32]
+    mov     TMP2, VX, asr #16
+    add     VX, VX, UNIT_X
+    add     TMP2, mem_operand, TMP2, asl #2
+    vld1.32 {d&reg1&[1]}, [TMP1, :32]
+    vld1.32 {d&reg2&[1]}, [TMP2, :32]
+.else
+    pixld1_s elem_size, reg1, mem_operand
+    pixld1_s elem_size, reg2, mem_operand
+.endif
+.endm
+
+.macro pixld0_s elem_size, reg1, idx, mem_operand
+.if elem_size == 16
+    mov     TMP1, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP1, mem_operand, TMP1, asl #1
+    vld1.16 {d&reg1&[idx]}, [TMP1, :16]
+.elseif elem_size == 32
+    mov     TMP1, VX, asr #16
+    adds    VX, VX, UNIT_X
+5:  subpls  VX, VX, SRC_WIDTH_FIXED
+    bpl     5b
+    add     TMP1, mem_operand, TMP1, asl #2
+    vld1.32 {d&reg1&[idx]}, [TMP1, :32]
+.endif
+.endm
+
+.macro pixld_s_internal numbytes, elem_size, basereg, mem_operand
+.if numbytes == 32
+    pixld2_s elem_size, %(basereg+4), %(basereg+5), mem_operand
+    pixld2_s elem_size, %(basereg+6), %(basereg+7), mem_operand
+    pixdeinterleave elem_size, %(basereg+4)
+.elseif numbytes == 16
+    pixld2_s elem_size, %(basereg+2), %(basereg+3), mem_operand
+.elseif numbytes == 8
+    pixld1_s elem_size, %(basereg+1), mem_operand
+.elseif numbytes == 4
+    .if elem_size == 32
+        pixld0_s elem_size, %(basereg+0), 1, mem_operand
+    .elseif elem_size == 16
+        pixld0_s elem_size, %(basereg+0), 2, mem_operand
+        pixld0_s elem_size, %(basereg+0), 3, mem_operand
+    .else
+        pixld0_s elem_size, %(basereg+0), 4, mem_operand
+        pixld0_s elem_size, %(basereg+0), 5, mem_operand
+        pixld0_s elem_size, %(basereg+0), 6, mem_operand
+        pixld0_s elem_size, %(basereg+0), 7, mem_operand
+    .endif
+.elseif numbytes == 2
+    .if elem_size == 16
+        pixld0_s elem_size, %(basereg+0), 1, mem_operand
+    .else
+        pixld0_s elem_size, %(basereg+0), 2, mem_operand
+        pixld0_s elem_size, %(basereg+0), 3, mem_operand
+    .endif
+.elseif numbytes == 1
+    pixld0_s elem_size, %(basereg+0), 1, mem_operand
+.else
+    .error "unsupported size: numbytes"
+.endif
+.endm
+
+.macro pixld_s numpix, bpp, basereg, mem_operand
+.if bpp > 0
+    pixld_s_internal %(numpix * bpp / 8), %(bpp), basereg, mem_operand
+.endif
+.endm
+
+.macro vuzp8 reg1, reg2
+    vuzp.8 d&reg1, d&reg2
+.endm
+
+.macro vzip8 reg1, reg2
+    vzip.8 d&reg1, d&reg2
+.endm
+
+/* deinterleave B, G, R, A channels for eight 32bpp pixels in 4 registers */
+.macro pixdeinterleave bpp, basereg
+.if (bpp == 32) && (DEINTERLEAVE_32BPP_ENABLED != 0)
+    vuzp8 %(basereg+0), %(basereg+1)
+    vuzp8 %(basereg+2), %(basereg+3)
+    vuzp8 %(basereg+1), %(basereg+3)
+    vuzp8 %(basereg+0), %(basereg+2)
+.endif
+.endm
+
+/* interleave B, G, R, A channels for eight 32bpp pixels in 4 registers */
+.macro pixinterleave bpp, basereg
+.if (bpp == 32) && (DEINTERLEAVE_32BPP_ENABLED != 0)
+    vzip8 %(basereg+0), %(basereg+2)
+    vzip8 %(basereg+1), %(basereg+3)
+    vzip8 %(basereg+2), %(basereg+3)
+    vzip8 %(basereg+0), %(basereg+1)
+.endif
+.endm
+
+/*
+ * This is a macro for implementing cache preload. The main idea is that
+ * cache preload logic is mostly independent from the rest of pixels
+ * processing code. It starts at the top left pixel and moves forward
+ * across pixels and can jump across scanlines. Prefetch distance is
+ * handled in an 'incremental' way: it starts from 0 and advances to the
+ * optimal distance over time. After reaching optimal prefetch distance,
+ * it is kept constant. There are some checks which prevent prefetching
+ * unneeded pixel lines below the image (but it still can prefetch a bit
+ * more data on the right side of the image - not a big issue and may
+ * be actually helpful when rendering text glyphs). Additional trick is
+ * the use of LDR instruction for prefetch instead of PLD when moving to
+ * the next line, the point is that we have a high chance of getting TLB
+ * miss in this case, and PLD would be useless.
+ *
+ * This sounds like it may introduce a noticeable overhead (when working with
+ * fully cached data). But in reality, due to having a separate pipeline and
+ * instruction queue for NEON unit in ARM Cortex-A8, normal ARM code can
+ * execute simultaneously with NEON and be completely shadowed by it. Thus
+ * we get no performance overhead at all (*). This looks like a very nice
+ * feature of Cortex-A8, if used wisely. We don't have a hardware prefetcher,
+ * but still can implement some rather advanced prefetch logic in software
+ * for almost zero cost!
+ *
+ * (*) The overhead of the prefetcher is visible when running some trivial
+ * pixels processing like simple copy. Anyway, having prefetch is a must
+ * when working with the graphics data.
+ */
+.macro PF a, x:vararg
+.if (PREFETCH_TYPE_CURRENT == PREFETCH_TYPE_ADVANCED)
+    a x
+.endif
+.endm
+
+.macro cache_preload std_increment, boost_increment
+.if (src_bpp_shift >= 0) || (dst_r_bpp != 0) || (mask_bpp_shift >= 0)
+.if regs_shortage
+    PF ldr ORIG_W, [sp] /* If we are short on regs, ORIG_W is kept on stack */
+.endif
+.if std_increment != 0
+    PF add PF_X, PF_X, #std_increment
+.endif
+    PF tst PF_CTL, #0xF
+    PF addne PF_X, PF_X, #boost_increment
+    PF subne PF_CTL, PF_CTL, #1
+    PF cmp PF_X, ORIG_W
+.if src_bpp_shift >= 0
+    PF pld, [PF_SRC, PF_X, lsl #src_bpp_shift]
+.endif
+.if dst_r_bpp != 0
+    PF pld, [PF_DST, PF_X, lsl #dst_bpp_shift]
+.endif
+.if mask_bpp_shift >= 0
+    PF pld, [PF_MASK, PF_X, lsl #mask_bpp_shift]
+.endif
+    PF subge PF_X, PF_X, ORIG_W
+    PF subges PF_CTL, PF_CTL, #0x10
+.if src_bpp_shift >= 0
+    PF ldrgeb DUMMY, [PF_SRC, SRC_STRIDE, lsl #src_bpp_shift]!
+.endif
+.if dst_r_bpp != 0
+    PF ldrgeb DUMMY, [PF_DST, DST_STRIDE, lsl #dst_bpp_shift]!
+.endif
+.if mask_bpp_shift >= 0
+    PF ldrgeb DUMMY, [PF_MASK, MASK_STRIDE, lsl #mask_bpp_shift]!
+.endif
+.endif
+.endm
+
+.macro cache_preload_simple
+.if (PREFETCH_TYPE_CURRENT == PREFETCH_TYPE_SIMPLE)
+.if src_bpp > 0
+    pld [SRC, #(PREFETCH_DISTANCE_SIMPLE * src_bpp / 8)]
+.endif
+.if dst_r_bpp > 0
+    pld [DST_R, #(PREFETCH_DISTANCE_SIMPLE * dst_r_bpp / 8)]
+.endif
+.if mask_bpp > 0
+    pld [MASK, #(PREFETCH_DISTANCE_SIMPLE * mask_bpp / 8)]
+.endif
+.endif
+.endm
+
+.macro fetch_mask_pixblock
+    pixld       pixblock_size, mask_bpp, \
+                (mask_basereg - pixblock_size * mask_bpp / 64), MASK
+.endm
+
+/*
+ * Macro which is used to process leading pixels until destination
+ * pointer is properly aligned (at 16 bytes boundary). When destination
+ * buffer uses 16bpp format, this is unnecessary, or even pointless.
+ */
+.macro ensure_destination_ptr_alignment process_pixblock_head, \
+                                        process_pixblock_tail, \
+                                        process_pixblock_tail_head
+.if dst_w_bpp != 24
+    tst         DST_R, #0xF
+    beq         2f
+
+.irp lowbit, 1, 2, 4, 8, 16
+local skip1
+.if (dst_w_bpp <= (lowbit * 8)) && ((lowbit * 8) < (pixblock_size * dst_w_bpp))
+.if lowbit < 16 /* we don't need more than 16-byte alignment */
+    tst         DST_R, #lowbit
+    beq         1f
+.endif
+    pixld_src   (lowbit * 8 / dst_w_bpp), src_bpp, src_basereg, SRC
+    pixld       (lowbit * 8 / dst_w_bpp), mask_bpp, mask_basereg, MASK
+.if dst_r_bpp > 0
+    pixld_a     (lowbit * 8 / dst_r_bpp), dst_r_bpp, dst_r_basereg, DST_R
+.else
+    add         DST_R, DST_R, #lowbit
+.endif
+    PF add      PF_X, PF_X, #(lowbit * 8 / dst_w_bpp)
+    sub         W, W, #(lowbit * 8 / dst_w_bpp)
+1:
+.endif
+.endr
+    pixdeinterleave src_bpp, src_basereg
+    pixdeinterleave mask_bpp, mask_basereg
+    pixdeinterleave dst_r_bpp, dst_r_basereg
+
+    process_pixblock_head
+    cache_preload 0, pixblock_size
+    cache_preload_simple
+    process_pixblock_tail
+
+    pixinterleave dst_w_bpp, dst_w_basereg
+.irp lowbit, 1, 2, 4, 8, 16
+.if (dst_w_bpp <= (lowbit * 8)) && ((lowbit * 8) < (pixblock_size * dst_w_bpp))
+.if lowbit < 16 /* we don't need more than 16-byte alignment */
+    tst         DST_W, #lowbit
+    beq         1f
+.endif
+    pixst_a     (lowbit * 8 / dst_w_bpp), dst_w_bpp, dst_w_basereg, DST_W
+1:
+.endif
+.endr
+.endif
+2:
+.endm
+
+/*
+ * Special code for processing up to (pixblock_size - 1) remaining
+ * trailing pixels. As SIMD processing performs operation on
+ * pixblock_size pixels, anything smaller than this has to be loaded
+ * and stored in a special way. Loading and storing of pixel data is
+ * performed in such a way that we fill some 'slots' in the NEON
+ * registers (some slots naturally are unused), then perform compositing
+ * operation as usual. In the end, the data is taken from these 'slots'
+ * and saved to memory.
+ *
+ * cache_preload_flag - allows to suppress prefetch if
+ *                      set to 0
+ * dst_aligned_flag   - selects whether destination buffer
+ *                      is aligned
+ */
+.macro process_trailing_pixels cache_preload_flag, \
+                               dst_aligned_flag, \
+                               process_pixblock_head, \
+                               process_pixblock_tail, \
+                               process_pixblock_tail_head
+    tst         W, #(pixblock_size - 1)
+    beq         2f
+.irp chunk_size, 16, 8, 4, 2, 1
+.if pixblock_size > chunk_size
+    tst         W, #chunk_size
+    beq         1f
+    pixld_src   chunk_size, src_bpp, src_basereg, SRC
+    pixld       chunk_size, mask_bpp, mask_basereg, MASK
+.if dst_aligned_flag != 0
+    pixld_a     chunk_size, dst_r_bpp, dst_r_basereg, DST_R
+.else
+    pixld       chunk_size, dst_r_bpp, dst_r_basereg, DST_R
+.endif
+.if cache_preload_flag != 0
+    PF add      PF_X, PF_X, #chunk_size
+.endif
+1:
+.endif
+.endr
+    pixdeinterleave src_bpp, src_basereg
+    pixdeinterleave mask_bpp, mask_basereg
+    pixdeinterleave dst_r_bpp, dst_r_basereg
+
+    process_pixblock_head
+.if cache_preload_flag != 0
+    cache_preload 0, pixblock_size
+    cache_preload_simple
+.endif
+    process_pixblock_tail
+    pixinterleave dst_w_bpp, dst_w_basereg
+.irp chunk_size, 16, 8, 4, 2, 1
+.if pixblock_size > chunk_size
+    tst         W, #chunk_size
+    beq         1f
+.if dst_aligned_flag != 0
+    pixst_a     chunk_size, dst_w_bpp, dst_w_basereg, DST_W
+.else
+    pixst       chunk_size, dst_w_bpp, dst_w_basereg, DST_W
+.endif
+1:
+.endif
+.endr
+2:
+.endm
+
+/*
+ * Macro, which performs all the needed operations to switch to the next
+ * scanline and start the next loop iteration unless all the scanlines
+ * are already processed.
+ */
+.macro advance_to_next_scanline start_of_loop_label
+.if regs_shortage
+    ldrd        W, [sp] /* load W and H (width and height) from stack */
+.else
+    mov         W, ORIG_W
+.endif
+    add         DST_W, DST_W, DST_STRIDE, lsl #dst_bpp_shift
+.if src_bpp != 0
+    add         SRC, SRC, SRC_STRIDE, lsl #src_bpp_shift
+.endif
+.if mask_bpp != 0
+    add         MASK, MASK, MASK_STRIDE, lsl #mask_bpp_shift
+.endif
+.if (dst_w_bpp != 24)
+    sub         DST_W, DST_W, W, lsl #dst_bpp_shift
+.endif
+.if (src_bpp != 24) && (src_bpp != 0)
+    sub         SRC, SRC, W, lsl #src_bpp_shift
+.endif
+.if (mask_bpp != 24) && (mask_bpp != 0)
+    sub         MASK, MASK, W, lsl #mask_bpp_shift
+.endif
+    subs        H, H, #1
+    mov         DST_R, DST_W
+.if regs_shortage
+    str         H, [sp, #4] /* save updated height to stack */
+.endif
+    bge         start_of_loop_label
+.endm
+
+/*
+ * Registers are allocated in the following way by default:
+ * d0, d1, d2, d3     - reserved for loading source pixel data
+ * d4, d5, d6, d7     - reserved for loading destination pixel data
+ * d24, d25, d26, d27 - reserved for loading mask pixel data
+ * d28, d29, d30, d31 - final destination pixel data for writeback to memory
+ */
+.macro generate_composite_function fname, \
+                                   src_bpp_, \
+                                   mask_bpp_, \
+                                   dst_w_bpp_, \
+                                   flags, \
+                                   pixblock_size_, \
+                                   prefetch_distance, \
+                                   init, \
+                                   cleanup, \
+                                   process_pixblock_head, \
+                                   process_pixblock_tail, \
+                                   process_pixblock_tail_head, \
+                                   dst_w_basereg_ = 28, \
+                                   dst_r_basereg_ = 4, \
+                                   src_basereg_   = 0, \
+                                   mask_basereg_  = 24
+
+    pixman_asm_function fname
+
+    push        {r4-r12, lr}        /* save all registers */
+
+/*
+ * Select prefetch type for this function. If prefetch distance is
+ * set to 0 or one of the color formats is 24bpp, SIMPLE prefetch
+ * has to be used instead of ADVANCED.
+ */
+    .set PREFETCH_TYPE_CURRENT, PREFETCH_TYPE_DEFAULT
+.if prefetch_distance == 0
+    .set PREFETCH_TYPE_CURRENT, PREFETCH_TYPE_NONE
+.elseif (PREFETCH_TYPE_CURRENT > PREFETCH_TYPE_SIMPLE) && \
+        ((src_bpp_ == 24) || (mask_bpp_ == 24) || (dst_w_bpp_ == 24))
+    .set PREFETCH_TYPE_CURRENT, PREFETCH_TYPE_SIMPLE
+.endif
+
+/*
+ * Make some macro arguments globally visible and accessible
+ * from other macros
+ */
+    .set src_bpp, src_bpp_
+    .set mask_bpp, mask_bpp_
+    .set dst_w_bpp, dst_w_bpp_
+    .set pixblock_size, pixblock_size_
+    .set dst_w_basereg, dst_w_basereg_
+    .set dst_r_basereg, dst_r_basereg_
+    .set src_basereg, src_basereg_
+    .set mask_basereg, mask_basereg_
+
+    .macro pixld_src x:vararg
+        pixld x
+    .endm
+    .macro fetch_src_pixblock
+        pixld_src   pixblock_size, src_bpp, \
+                    (src_basereg - pixblock_size * src_bpp / 64), SRC
+    .endm
+/*
+ * Assign symbolic names to registers
+ */
+    W           .req        r0      /* width (is updated during processing) */
+    H           .req        r1      /* height (is updated during processing) */
+    DST_W       .req        r2      /* destination buffer pointer for writes */
+    DST_STRIDE  .req        r3      /* destination image stride */
+    SRC         .req        r4      /* source buffer pointer */
+    SRC_STRIDE  .req        r5      /* source image stride */
+    DST_R       .req        r6      /* destination buffer pointer for reads */
+
+    MASK        .req        r7      /* mask pointer */
+    MASK_STRIDE .req        r8      /* mask stride */
+
+    PF_CTL      .req        r9      /* combined lines counter and prefetch */
+                                    /* distance increment counter */
+    PF_X        .req        r10     /* pixel index in a scanline for current */
+                                    /* pretetch position */
+    PF_SRC      .req        r11     /* pointer to source scanline start */
+                                    /* for prefetch purposes */
+    PF_DST      .req        r12     /* pointer to destination scanline start */
+                                    /* for prefetch purposes */
+    PF_MASK     .req        r14     /* pointer to mask scanline start */
+                                    /* for prefetch purposes */
+/*
+ * Check whether we have enough registers for all the local variables.
+ * If we don't have enough registers, original width and height are
+ * kept on top of stack (and 'regs_shortage' variable is set to indicate
+ * this for the rest of code). Even if there are enough registers, the
+ * allocation scheme may be a bit different depending on whether source
+ * or mask is not used.
+ */
+.if (PREFETCH_TYPE_CURRENT < PREFETCH_TYPE_ADVANCED)
+    ORIG_W      .req        r10     /* saved original width */
+    DUMMY       .req        r12     /* temporary register */
+    .set        regs_shortage, 0
+.elseif mask_bpp == 0
+    ORIG_W      .req        r7      /* saved original width */
+    DUMMY       .req        r8      /* temporary register */
+    .set        regs_shortage, 0
+.elseif src_bpp == 0
+    ORIG_W      .req        r4      /* saved original width */
+    DUMMY       .req        r5      /* temporary register */
+    .set        regs_shortage, 0
+.else
+    ORIG_W      .req        r1      /* saved original width */
+    DUMMY       .req        r1      /* temporary register */
+    .set        regs_shortage, 1
+.endif
+
+    .set mask_bpp_shift, -1
+.if src_bpp == 32
+    .set src_bpp_shift, 2
+.elseif src_bpp == 24
+    .set src_bpp_shift, 0
+.elseif src_bpp == 16
+    .set src_bpp_shift, 1
+.elseif src_bpp == 8
+    .set src_bpp_shift, 0
+.elseif src_bpp == 0
+    .set src_bpp_shift, -1
+.else
+    .error "requested src bpp (src_bpp) is not supported"
+.endif
+.if mask_bpp == 32
+    .set mask_bpp_shift, 2
+.elseif mask_bpp == 24
+    .set mask_bpp_shift, 0
+.elseif mask_bpp == 8
+    .set mask_bpp_shift, 0
+.elseif mask_bpp == 0
+    .set mask_bpp_shift, -1
+.else
+    .error "requested mask bpp (mask_bpp) is not supported"
+.endif
+.if dst_w_bpp == 32
+    .set dst_bpp_shift, 2
+.elseif dst_w_bpp == 24
+    .set dst_bpp_shift, 0
+.elseif dst_w_bpp == 16
+    .set dst_bpp_shift, 1
+.elseif dst_w_bpp == 8
+    .set dst_bpp_shift, 0
+.else
+    .error "requested dst bpp (dst_w_bpp) is not supported"
+.endif
+
+.if (((flags) & FLAG_DST_READWRITE) != 0)
+    .set dst_r_bpp, dst_w_bpp
+.else
+    .set dst_r_bpp, 0
+.endif
+.if (((flags) & FLAG_DEINTERLEAVE_32BPP) != 0)
+    .set DEINTERLEAVE_32BPP_ENABLED, 1
+.else
+    .set DEINTERLEAVE_32BPP_ENABLED, 0
+.endif
+
+.if prefetch_distance < 0 || prefetch_distance > 15
+    .error "invalid prefetch distance (prefetch_distance)"
+.endif
+
+.if src_bpp > 0
+    ldr         SRC, [sp, #40]
+.endif
+.if mask_bpp > 0
+    ldr         MASK, [sp, #48]
+.endif
+    PF mov      PF_X, #0
+.if src_bpp > 0
+    ldr         SRC_STRIDE, [sp, #44]
+.endif
+.if mask_bpp > 0
+    ldr         MASK_STRIDE, [sp, #52]
+.endif
+    mov         DST_R, DST_W
+
+.if src_bpp == 24
+    sub         SRC_STRIDE, SRC_STRIDE, W
+    sub         SRC_STRIDE, SRC_STRIDE, W, lsl #1
+.endif
+.if mask_bpp == 24
+    sub         MASK_STRIDE, MASK_STRIDE, W
+    sub         MASK_STRIDE, MASK_STRIDE, W, lsl #1
+.endif
+.if dst_w_bpp == 24
+    sub         DST_STRIDE, DST_STRIDE, W
+    sub         DST_STRIDE, DST_STRIDE, W, lsl #1
+.endif
+
+/*
+ * Setup advanced prefetcher initial state
+ */
+    PF mov      PF_SRC, SRC
+    PF mov      PF_DST, DST_R
+    PF mov      PF_MASK, MASK
+    /* PF_CTL = prefetch_distance | ((h - 1) << 4) */
+    PF mov      PF_CTL, H, lsl #4
+    PF add      PF_CTL, #(prefetch_distance - 0x10)
+
+    init
+.if regs_shortage
+    push        {r0, r1}
+.endif
+    subs        H, H, #1
+.if regs_shortage
+    str         H, [sp, #4] /* save updated height to stack */
+.else
+    mov         ORIG_W, W
+.endif
+    blt         9f
+    cmp         W, #(pixblock_size * 2)
+    blt         8f
+/*
+ * This is the start of the pipelined loop, which if optimized for
+ * long scanlines
+ */
+0:
+    ensure_destination_ptr_alignment process_pixblock_head, \
+                                     process_pixblock_tail, \
+                                     process_pixblock_tail_head
+
+    /* Implement "head (tail_head) ... (tail_head) tail" loop pattern */
+    pixld_a     pixblock_size, dst_r_bpp, \
+                (dst_r_basereg - pixblock_size * dst_r_bpp / 64), DST_R
+    fetch_src_pixblock
+    pixld       pixblock_size, mask_bpp, \
+                (mask_basereg - pixblock_size * mask_bpp / 64), MASK
+    PF add      PF_X, PF_X, #pixblock_size
+    process_pixblock_head
+    cache_preload 0, pixblock_size
+    cache_preload_simple
+    subs        W, W, #(pixblock_size * 2)
+    blt         2f
+1:
+    process_pixblock_tail_head
+    cache_preload_simple
+    subs        W, W, #pixblock_size
+    bge         1b
+2:
+    process_pixblock_tail
+    pixst_a     pixblock_size, dst_w_bpp, \
+                (dst_w_basereg - pixblock_size * dst_w_bpp / 64), DST_W
+
+    /* Process the remaining trailing pixels in the scanline */
+    process_trailing_pixels 1, 1, \
+                            process_pixblock_head, \
+                            process_pixblock_tail, \
+                            process_pixblock_tail_head
+    advance_to_next_scanline 0b
+
+.if regs_shortage
+    pop         {r0, r1}
+.endif
+    cleanup
+    pop         {r4-r12, pc}  /* exit */
+/*
+ * This is the start of the loop, designed to process images with small width
+ * (less than pixblock_size * 2 pixels). In this case neither pipelining
+ * nor prefetch are used.
+ */
+8:
+    /* Process exactly pixblock_size pixels if needed */
+    tst         W, #pixblock_size
+    beq         1f
+    pixld       pixblock_size, dst_r_bpp, \
+                (dst_r_basereg - pixblock_size * dst_r_bpp / 64), DST_R
+    fetch_src_pixblock
+    pixld       pixblock_size, mask_bpp, \
+                (mask_basereg - pixblock_size * mask_bpp / 64), MASK
+    process_pixblock_head
+    process_pixblock_tail
+    pixst       pixblock_size, dst_w_bpp, \
+                (dst_w_basereg - pixblock_size * dst_w_bpp / 64), DST_W
+1:
+    /* Process the remaining trailing pixels in the scanline */
+    process_trailing_pixels 0, 0, \
+                            process_pixblock_head, \
+                            process_pixblock_tail, \
+                            process_pixblock_tail_head
+    advance_to_next_scanline 8b
+9:
+.if regs_shortage
+    pop         {r0, r1}
+.endif
+    cleanup
+    pop         {r4-r12, pc}  /* exit */
+
+    .purgem     fetch_src_pixblock
+    .purgem     pixld_src
+
+    .unreq      SRC
+    .unreq      MASK
+    .unreq      DST_R
+    .unreq      DST_W
+    .unreq      ORIG_W
+    .unreq      W
+    .unreq      H
+    .unreq      SRC_STRIDE
+    .unreq      DST_STRIDE
+    .unreq      MASK_STRIDE
+    .unreq      PF_CTL
+    .unreq      PF_X
+    .unreq      PF_SRC
+    .unreq      PF_DST
+    .unreq      PF_MASK
+    .unreq      DUMMY
+    .endfunc
+.endm
+
+/*
+ * A simplified variant of function generation template for a single
+ * scanline processing (for implementing pixman combine functions)
+ */
+.macro generate_composite_function_scanline        use_nearest_scaling, \
+                                                   fname, \
+                                                   src_bpp_, \
+                                                   mask_bpp_, \
+                                                   dst_w_bpp_, \
+                                                   flags, \
+                                                   pixblock_size_, \
+                                                   init, \
+                                                   cleanup, \
+                                                   process_pixblock_head, \
+                                                   process_pixblock_tail, \
+                                                   process_pixblock_tail_head, \
+                                                   dst_w_basereg_ = 28, \
+                                                   dst_r_basereg_ = 4, \
+                                                   src_basereg_   = 0, \
+                                                   mask_basereg_  = 24
+
+    pixman_asm_function fname
+
+    .set PREFETCH_TYPE_CURRENT, PREFETCH_TYPE_NONE
+/*
+ * Make some macro arguments globally visible and accessible
+ * from other macros
+ */
+    .set src_bpp, src_bpp_
+    .set mask_bpp, mask_bpp_
+    .set dst_w_bpp, dst_w_bpp_
+    .set pixblock_size, pixblock_size_
+    .set dst_w_basereg, dst_w_basereg_
+    .set dst_r_basereg, dst_r_basereg_
+    .set src_basereg, src_basereg_
+    .set mask_basereg, mask_basereg_
+
+.if use_nearest_scaling != 0
+    /*
+     * Assign symbolic names to registers for nearest scaling
+     */
+    W           .req        r0
+    DST_W       .req        r1
+    SRC         .req        r2
+    VX          .req        r3
+    UNIT_X      .req        ip
+    MASK        .req        lr
+    TMP1        .req        r4
+    TMP2        .req        r5
+    DST_R       .req        r6
+    SRC_WIDTH_FIXED .req        r7
+
+    .macro pixld_src x:vararg
+        pixld_s x
+    .endm
+
+    ldr         UNIT_X, [sp]
+    push        {r4-r8, lr}
+    ldr         SRC_WIDTH_FIXED, [sp, #(24 + 4)]
+    .if mask_bpp != 0
+    ldr         MASK, [sp, #(24 + 8)]
+    .endif
+.else
+    /*
+     * Assign symbolic names to registers
+     */
+    W           .req        r0      /* width (is updated during processing) */
+    DST_W       .req        r1      /* destination buffer pointer for writes */
+    SRC         .req        r2      /* source buffer pointer */
+    DST_R       .req        ip      /* destination buffer pointer for reads */
+    MASK        .req        r3      /* mask pointer */
+
+    .macro pixld_src x:vararg
+        pixld x
+    .endm
+.endif
+
+.if (((flags) & FLAG_DST_READWRITE) != 0)
+    .set dst_r_bpp, dst_w_bpp
+.else
+    .set dst_r_bpp, 0
+.endif
+.if (((flags) & FLAG_DEINTERLEAVE_32BPP) != 0)
+    .set DEINTERLEAVE_32BPP_ENABLED, 1
+.else
+    .set DEINTERLEAVE_32BPP_ENABLED, 0
+.endif
+
+    .macro fetch_src_pixblock
+        pixld_src   pixblock_size, src_bpp, \
+                    (src_basereg - pixblock_size * src_bpp / 64), SRC
+    .endm
+
+    init
+    mov         DST_R, DST_W
+
+    cmp         W, #pixblock_size
+    blt         8f
+
+    ensure_destination_ptr_alignment process_pixblock_head, \
+                                     process_pixblock_tail, \
+                                     process_pixblock_tail_head
+
+    subs        W, W, #pixblock_size
+    blt         7f
+
+    /* Implement "head (tail_head) ... (tail_head) tail" loop pattern */
+    pixld_a     pixblock_size, dst_r_bpp, \
+                (dst_r_basereg - pixblock_size * dst_r_bpp / 64), DST_R
+    fetch_src_pixblock
+    pixld       pixblock_size, mask_bpp, \
+                (mask_basereg - pixblock_size * mask_bpp / 64), MASK
+    process_pixblock_head
+    subs        W, W, #pixblock_size
+    blt         2f
+1:
+    process_pixblock_tail_head
+    subs        W, W, #pixblock_size
+    bge         1b
+2:
+    process_pixblock_tail
+    pixst_a     pixblock_size, dst_w_bpp, \
+                (dst_w_basereg - pixblock_size * dst_w_bpp / 64), DST_W
+7:
+    /* Process the remaining trailing pixels in the scanline (dst aligned) */
+    process_trailing_pixels 0, 1, \
+                            process_pixblock_head, \
+                            process_pixblock_tail, \
+                            process_pixblock_tail_head
+
+    cleanup
+.if use_nearest_scaling != 0
+    pop         {r4-r8, pc}  /* exit */
+.else
+    bx          lr  /* exit */
+.endif
+8:
+    /* Process the remaining trailing pixels in the scanline (dst unaligned) */
+    process_trailing_pixels 0, 0, \
+                            process_pixblock_head, \
+                            process_pixblock_tail, \
+                            process_pixblock_tail_head
+
+    cleanup
+
+.if use_nearest_scaling != 0
+    pop         {r4-r8, pc}  /* exit */
+
+    .unreq      DST_R
+    .unreq      SRC
+    .unreq      W
+    .unreq      VX
+    .unreq      UNIT_X
+    .unreq      TMP1
+    .unreq      TMP2
+    .unreq      DST_W
+    .unreq      MASK
+    .unreq      SRC_WIDTH_FIXED
+
+.else
+    bx          lr  /* exit */
+
+    .unreq      SRC
+    .unreq      MASK
+    .unreq      DST_R
+    .unreq      DST_W
+    .unreq      W
+.endif
+
+    .purgem     fetch_src_pixblock
+    .purgem     pixld_src
+
+    .endfunc
+.endm
+
+.macro generate_composite_function_single_scanline x:vararg
+    generate_composite_function_scanline 0, x
+.endm
+
+.macro generate_composite_function_nearest_scanline x:vararg
+    generate_composite_function_scanline 1, x
+.endm
+
+/* Default prologue/epilogue, nothing special needs to be done */
+
+.macro default_init
+.endm
+
+.macro default_cleanup
+.endm
+
+/*
+ * Prologue/epilogue variant which additionally saves/restores d8-d15
+ * registers (they need to be saved/restored by callee according to ABI).
+ * This is required if the code needs to use all the NEON registers.
+ */
+
+.macro default_init_need_all_regs
+    vpush       {d8-d15}
+.endm
+
+.macro default_cleanup_need_all_regs
+    vpop        {d8-d15}
+.endm
+
+/******************************************************************************/
+
+/*
+ * Conversion of 8 r5g6b6 pixels packed in 128-bit register (in)
+ * into a planar a8r8g8b8 format (with a, r, g, b color components
+ * stored into 64-bit registers out_a, out_r, out_g, out_b respectively).
+ *
+ * Warning: the conversion is destructive and the original
+ *          value (in) is lost.
+ */
+.macro convert_0565_to_8888 in, out_a, out_r, out_g, out_b
+    vshrn.u16   out_r, in,    #8
+    vshrn.u16   out_g, in,    #3
+    vsli.u16    in,    in,    #5
+    vmov.u8     out_a, #255
+    vsri.u8     out_r, out_r, #5
+    vsri.u8     out_g, out_g, #6
+    vshrn.u16   out_b, in,    #2
+.endm
+
+.macro convert_0565_to_x888 in, out_r, out_g, out_b
+    vshrn.u16   out_r, in,    #8
+    vshrn.u16   out_g, in,    #3
+    vsli.u16    in,    in,    #5
+    vsri.u8     out_r, out_r, #5
+    vsri.u8     out_g, out_g, #6
+    vshrn.u16   out_b, in,    #2
+.endm
+
+/*
+ * Conversion from planar a8r8g8b8 format (with a, r, g, b color components
+ * in 64-bit registers in_a, in_r, in_g, in_b respectively) into 8 r5g6b6
+ * pixels packed in 128-bit register (out). Requires two temporary 128-bit
+ * registers (tmp1, tmp2)
+ */
+.macro convert_8888_to_0565 in_r, in_g, in_b, out, tmp1, tmp2
+    vshll.u8    tmp1, in_g, #8
+    vshll.u8    out, in_r, #8
+    vshll.u8    tmp2, in_b, #8
+    vsri.u16    out, tmp1, #5
+    vsri.u16    out, tmp2, #11
+.endm
+
+/*
+ * Conversion of four r5g6b5 pixels (in) to four x8r8g8b8 pixels
+ * returned in (out0, out1) registers pair. Requires one temporary
+ * 64-bit register (tmp). 'out1' and 'in' may overlap, the original
+ * value from 'in' is lost
+ */
+.macro convert_four_0565_to_x888_packed in, out0, out1, tmp
+    vshl.u16    out0, in,   #5  /* G top 6 bits */
+    vshl.u16    tmp,  in,   #11 /* B top 5 bits */
+    vsri.u16    in,   in,   #5  /* R is ready in top bits */
+    vsri.u16    out0, out0, #6  /* G is ready in top bits */
+    vsri.u16    tmp,  tmp,  #5  /* B is ready in top bits */
+    vshr.u16    out1, in,   #8  /* R is in place */
+    vsri.u16    out0, tmp,  #8  /* G & B is in place */
+    vzip.u16    out0, out1      /* everything is in place */
+.endm