From: Søren Sandmann Pedersen Date: Thu, 6 Jun 2013 20:15:39 +0000 (-0400) Subject: ssse3: Add iterator for separable bilinear scaling X-Git-Tag: pixman-0.31.2~36 X-Git-Url: http://review.tizen.org/git/?a=commitdiff_plain;h=58a79dfe6d1fd62c2b66c69fdb64f6b8ecf61da5;p=platform%2Fupstream%2Fpixman.git ssse3: Add iterator for separable bilinear scaling This new iterator uses the SSSE3 instructions pmaddubsw and pabsw to implement a fast iterator for bilinear scaling. There is a graph here recording the per-pixel time for various bilinear scaling algorithms as reported by scaling-bench: http://people.freedesktop.org/~sandmann/ssse3.v2/ssse3.v2.png As the graph shows, this new iterator is clearly faster than the existing C iterator, and when used with an SSE2 combiner, it is also faster than the existing SSE2 fast paths for upscaling, though not for downscaling. Another graph: http://people.freedesktop.org/~sandmann/ssse3.v2/movdqu.png shows the difference between writing to iter->buffer with movdqa, movdqu on an aligned buffer, and movdqu on a deliberately unaligned buffer. Since the differences are very small, the patch here avoids using movdqa because imposing alignment restrictions on iter->buffer may interfere with other optimizations, such as writing directly to the destination image. The data was measured with scaling-bench on a Sandy Bridge Core i3-2350M @ 2.3GHz and is available in this directory: http://people.freedesktop.org/~sandmann/ssse3.v2/ where there is also a Gnumeric spreadsheet ssse3.v2.gnumeric containing the per-pixel values and the graph. V2: - Use uintptr_t instead of unsigned long in the ALIGN macro - Use _mm_storel_epi64 instead of _mm_cvtsi128_si64 as the latter form is not available on x86-32. - Use _mm_storeu_si128() instead of _mm_store_si128() to avoid imposing alignment requirements on iter->buffer --- diff --git a/pixman/pixman-ssse3.c b/pixman/pixman-ssse3.c index 19d71e7..34763e2 100644 --- a/pixman/pixman-ssse3.c +++ b/pixman/pixman-ssse3.c @@ -35,6 +35,316 @@ #include "pixman-private.h" #include "pixman-inlines.h" +typedef struct +{ + int y; + uint64_t * buffer; +} line_t; + +typedef struct +{ + line_t line0; + line_t line1; + pixman_fixed_t y; + pixman_fixed_t x; + uint64_t data[1]; +} bilinear_info_t; + +static void +ssse3_fetch_horizontal (bits_image_t *image, line_t *line, + int y, pixman_fixed_t x, pixman_fixed_t ux, int n) +{ + uint32_t *bits = image->bits + y * image->rowstride; + __m128i vx = _mm_set_epi16 ( + - (x + 1), x, - (x + 1), x, + - (x + ux + 1), x + ux, - (x + ux + 1), x + ux); + __m128i vux = _mm_set_epi16 ( + - 2 * ux, 2 * ux, - 2 * ux, 2 * ux, + - 2 * ux, 2 * ux, - 2 * ux, 2 * ux); + __m128i vaddc = _mm_set_epi16 (1, 0, 1, 0, 1, 0, 1, 0); + __m128i *b = (__m128i *)line->buffer; + __m128i vrl0, vrl1; + + while ((n -= 2) >= 0) + { + __m128i vw, vr, s; + + vrl1 = _mm_loadl_epi64 ( + (__m128i *)(bits + pixman_fixed_to_int (x + ux))); + /* vrl1: R1, L1 */ + + final_pixel: + vrl0 = _mm_loadl_epi64 ( + (__m128i *)(bits + pixman_fixed_to_int (x))); + /* vrl0: R0, L0 */ + + /* The weights are based on vx which is a vector of + * + * - (x + 1), x, - (x + 1), x, + * - (x + ux + 1), x + ux, - (x + ux + 1), x + ux + * + * so the 16 bit weights end up like this: + * + * iw0, w0, iw0, w0, iw1, w1, iw1, w1 + * + * and after shifting and packing, we get these bytes: + * + * iw0, w0, iw0, w0, iw1, w1, iw1, w1, + * iw0, w0, iw0, w0, iw1, w1, iw1, w1, + * + * which means the first and the second input pixel + * have to be interleaved like this: + * + * la0, ra0, lr0, rr0, la1, ra1, lr1, rr1, + * lg0, rg0, lb0, rb0, lg1, rg1, lb1, rb1 + * + * before maddubsw can be used. + */ + + vw = _mm_add_epi16 ( + vaddc, _mm_srli_epi16 (vx, 16 - BILINEAR_INTERPOLATION_BITS)); + /* vw: iw0, w0, iw0, w0, iw1, w1, iw1, w1 + */ + + vw = _mm_packus_epi16 (vw, vw); + /* vw: iw0, w0, iw0, w0, iw1, w1, iw1, w1, + * iw0, w0, iw0, w0, iw1, w1, iw1, w1 + */ + vx = _mm_add_epi16 (vx, vux); + + x += 2 * ux; + + vr = _mm_unpacklo_epi16 (vrl1, vrl0); + /* vr: rar0, rar1, rgb0, rgb1, lar0, lar1, lgb0, lgb1 */ + + s = _mm_shuffle_epi32 (vr, _MM_SHUFFLE (1, 0, 3, 2)); + /* s: lar0, lar1, lgb0, lgb1, rar0, rar1, rgb0, rgb1 */ + + vr = _mm_unpackhi_epi8 (vr, s); + /* vr: la0, ra0, lr0, rr0, la1, ra1, lr1, rr1, + * lg0, rg0, lb0, rb0, lg1, rg1, lb1, rb1 + */ + + vr = _mm_maddubs_epi16 (vr, vw); + + /* When the weight is 0, the inverse weight is + * 128 which can't be represented in a signed byte. + * As a result maddubsw computes the following: + * + * r = l * -128 + r * 0 + * + * rather than the desired + * + * r = l * 128 + r * 0 + * + * We fix this by taking the absolute value of the + * result. + */ + vr = _mm_abs_epi16 (vr); + + /* vr: A0, R0, A1, R1, G0, B0, G1, B1 */ + _mm_store_si128 (b++, vr); + } + + if (n == -1) + { + vrl1 = _mm_setzero_si128(); + goto final_pixel; + } + + line->y = y; +} + +static uint32_t * +ssse3_fetch_bilinear_cover (pixman_iter_t *iter, const uint32_t *mask) +{ + pixman_fixed_t fx, ux; + bilinear_info_t *info = iter->data; + line_t *line0, *line1; + int y0, y1; + int32_t dist_y; + __m128i vw; + int i; + + fx = info->x; + ux = iter->image->common.transform->matrix[0][0]; + + y0 = pixman_fixed_to_int (info->y); + y1 = y0 + 1; + + line0 = &info->line0; + line1 = &info->line1; + + if (line0->y != y0 || line1->y != y1) + { + if (line0->y == y1 || line1->y == y0) + { + line_t tmp = *line0; + *line0 = *line1; + *line1 = tmp; + } + + if (line0->y != y0) + { + ssse3_fetch_horizontal ( + &iter->image->bits, line0, y0, fx, ux, iter->width); + } + + if (line1->y != y1) + { + ssse3_fetch_horizontal ( + &iter->image->bits, line1, y1, fx, ux, iter->width); + } + } + + dist_y = pixman_fixed_to_bilinear_weight (info->y); + dist_y <<= (16 - BILINEAR_INTERPOLATION_BITS); + + vw = _mm_set_epi16 ( + dist_y, dist_y, dist_y, dist_y, dist_y, dist_y, dist_y, dist_y); + + for (i = 0; i + 3 < iter->width; i += 4) + { + __m128i top0 = _mm_load_si128 ((__m128i *)(line0->buffer + i)); + __m128i bot0 = _mm_load_si128 ((__m128i *)(line1->buffer + i)); + __m128i top1 = _mm_load_si128 ((__m128i *)(line0->buffer + i + 2)); + __m128i bot1 = _mm_load_si128 ((__m128i *)(line1->buffer + i + 2)); + __m128i r0, r1, tmp, p; + + r0 = _mm_mulhi_epu16 ( + _mm_sub_epi16 (bot0, top0), vw); + tmp = _mm_cmplt_epi16 (bot0, top0); + tmp = _mm_and_si128 (tmp, vw); + r0 = _mm_sub_epi16 (r0, tmp); + r0 = _mm_add_epi16 (r0, top0); + r0 = _mm_srli_epi16 (r0, BILINEAR_INTERPOLATION_BITS); + /* r0: A0 R0 A1 R1 G0 B0 G1 B1 */ + r0 = _mm_shuffle_epi32 (r0, _MM_SHUFFLE (2, 0, 3, 1)); + /* r0: A1 R1 G1 B1 A0 R0 G0 B0 */ + + r1 = _mm_mulhi_epu16 ( + _mm_sub_epi16 (bot1, top1), vw); + tmp = _mm_cmplt_epi16 (bot1, top1); + tmp = _mm_and_si128 (tmp, vw); + r1 = _mm_sub_epi16 (r1, tmp); + r1 = _mm_add_epi16 (r1, top1); + r1 = _mm_srli_epi16 (r1, BILINEAR_INTERPOLATION_BITS); + r1 = _mm_shuffle_epi32 (r1, _MM_SHUFFLE (2, 0, 3, 1)); + /* r1: A3 R3 G3 B3 A2 R2 G2 B2 */ + + p = _mm_packus_epi16 (r0, r1); + + _mm_storeu_si128 ((__m128i *)(iter->buffer + i), p); + } + + while (i < iter->width) + { + __m128i top0 = _mm_load_si128 ((__m128i *)(line0->buffer + i)); + __m128i bot0 = _mm_load_si128 ((__m128i *)(line1->buffer + i)); + __m128i r0, tmp, p; + + r0 = _mm_mulhi_epu16 ( + _mm_sub_epi16 (bot0, top0), vw); + tmp = _mm_cmplt_epi16 (bot0, top0); + tmp = _mm_and_si128 (tmp, vw); + r0 = _mm_sub_epi16 (r0, tmp); + r0 = _mm_add_epi16 (r0, top0); + r0 = _mm_srli_epi16 (r0, BILINEAR_INTERPOLATION_BITS); + /* r0: A0 R0 A1 R1 G0 B0 G1 B1 */ + r0 = _mm_shuffle_epi32 (r0, _MM_SHUFFLE (2, 0, 3, 1)); + /* r0: A1 R1 G1 B1 A0 R0 G0 B0 */ + + p = _mm_packus_epi16 (r0, r0); + + if (iter->width - i == 1) + { + *(uint32_t *)(iter->buffer + i) = _mm_cvtsi128_si32 (p); + i++; + } + else + { + _mm_storel_epi64 ((__m128i *)(iter->buffer + i), p); + i += 2; + } + } + + info->y += iter->image->common.transform->matrix[1][1]; + + return iter->buffer; +} + +static void +ssse3_bilinear_cover_iter_fini (pixman_iter_t *iter) +{ + free (iter->data); +} + +static void +ssse3_bilinear_cover_iter_init (pixman_iter_t *iter, const pixman_iter_info_t *iter_info) +{ + int width = iter->width; + bilinear_info_t *info; + pixman_vector_t v; + + /* Reference point is the center of the pixel */ + v.vector[0] = pixman_int_to_fixed (iter->x) + pixman_fixed_1 / 2; + v.vector[1] = pixman_int_to_fixed (iter->y) + pixman_fixed_1 / 2; + v.vector[2] = pixman_fixed_1; + + if (!pixman_transform_point_3d (iter->image->common.transform, &v)) + goto fail; + + info = malloc (sizeof (*info) + (2 * width - 1) * sizeof (uint64_t) + 64); + if (!info) + goto fail; + + info->x = v.vector[0] - pixman_fixed_1 / 2; + info->y = v.vector[1] - pixman_fixed_1 / 2; + +#define ALIGN(addr) \ + ((void *)((((uintptr_t)(addr)) + 15) & (~15))) + + /* It is safe to set the y coordinates to -1 initially + * because COVER_CLIP_BILINEAR ensures that we will only + * be asked to fetch lines in the [0, height) interval + */ + info->line0.y = -1; + info->line0.buffer = ALIGN (&(info->data[0])); + info->line1.y = -1; + info->line1.buffer = ALIGN (info->line0.buffer + width); + + iter->get_scanline = ssse3_fetch_bilinear_cover; + iter->fini = ssse3_bilinear_cover_iter_fini; + + iter->data = info; + return; + +fail: + /* Something went wrong, either a bad matrix or OOM; in such cases, + * we don't guarantee any particular rendering. + */ + _pixman_log_error ( + FUNC, "Allocation failure or bad matrix, skipping rendering\n"); + + iter->get_scanline = _pixman_iter_get_scanline_noop; + iter->fini = NULL; +} + +static const pixman_iter_info_t ssse3_iters[] = +{ + { PIXMAN_a8r8g8b8, + (FAST_PATH_STANDARD_FLAGS | + FAST_PATH_SCALE_TRANSFORM | + FAST_PATH_BILINEAR_FILTER | + FAST_PATH_SAMPLES_COVER_CLIP_BILINEAR), + ITER_NARROW | ITER_SRC, + ssse3_bilinear_cover_iter_init, + NULL, NULL + }, + + { PIXMAN_null }, +}; + static const pixman_fast_path_t ssse3_fast_paths[] = { { PIXMAN_OP_NONE }, @@ -46,5 +356,7 @@ _pixman_implementation_create_ssse3 (pixman_implementation_t *fallback) pixman_implementation_t *imp = _pixman_implementation_create (fallback, ssse3_fast_paths); + imp->iter_info = ssse3_iters; + return imp; }