checkasm: add hscale test

This tests the hscale 8bpp to 14/18bpp functions with different filter
sizes.

Signed-off-by: Josh de Kock <josh@itanimul.li>

tests/checkasm/Makefile

@@ -45,7 +45,7 @@ AVFILTEROBJS-$(CONFIG_NLMEANS_FILTER)    += vf_nlmeans.o
 CHECKASMOBJS-$(CONFIG_AVFILTER) += $(AVFILTEROBJS-yes)
 
 # swscale tests
-SWSCALEOBJS                             += sw_rgb.o
+SWSCALEOBJS                             += sw_rgb.o sw_scale.o
 
 CHECKASMOBJS-$(CONFIG_SWSCALE)  += $(SWSCALEOBJS)
 

tests/checkasm/checkasm.c

@@ -183,6 +183,7 @@ static const struct {
 #endif
 #if CONFIG_SWSCALE
     { "sw_rgb", checkasm_check_sw_rgb },
+    { "sw_scale", checkasm_check_sw_scale },
 #endif
 #if CONFIG_AVUTIL
         { "fixed_dsp", checkasm_check_fixed_dsp },

tests/checkasm/checkasm.h

@@ -69,6 +69,7 @@ void checkasm_check_pixblockdsp(void);
 void checkasm_check_sbrdsp(void);
 void checkasm_check_synth_filter(void);
 void checkasm_check_sw_rgb(void);
+void checkasm_check_sw_scale(void);
 void checkasm_check_utvideodsp(void);
 void checkasm_check_v210dec(void);
 void checkasm_check_v210enc(void);

tests/checkasm/sw_scale.c

@@ -0,0 +1,134 @@
+/*
+ *
+ * This file is part of FFmpeg.
+ *
+ * FFmpeg is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * FFmpeg is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License along
+ * with FFmpeg; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <string.h>
+
+#include "libavutil/common.h"
+#include "libavutil/intreadwrite.h"
+#include "libavutil/mem.h"
+
+#include "libswscale/swscale.h"
+#include "libswscale/swscale_internal.h"
+
+#include "checkasm.h"
+
+#define randomize_buffers(buf, size)      \
+    do {                                  \
+        int j;                            \
+        for (j = 0; j < size; j+=4)       \
+            AV_WN32(buf + j, rnd());      \
+    } while (0)
+
+#define SRC_PIXELS 128
+
+static void check_hscale(void)
+{
+#define MAX_FILTER_WIDTH 40
+#define FILTER_SIZES 5
+    static const int filter_sizes[FILTER_SIZES] = { 4, 8, 16, 32, 40 };
+
+#define HSCALE_PAIRS 2
+    static const int hscale_pairs[HSCALE_PAIRS][2] = {
+        { 8, 14 },
+        { 8, 18 },
+    };
+
+    int i, j, fsi, hpi, width;
+    struct SwsContext *ctx;
+
+    // padded
+    LOCAL_ALIGNED_32(uint8_t, src, [SRC_PIXELS + MAX_FILTER_WIDTH - 1]);
+    LOCAL_ALIGNED_32(uint32_t, dst0, [SRC_PIXELS]);
+    LOCAL_ALIGNED_32(uint32_t, dst1, [SRC_PIXELS]);
+
+    // padded
+    LOCAL_ALIGNED_32(int16_t, filter, [SRC_PIXELS * MAX_FILTER_WIDTH + MAX_FILTER_WIDTH]);
+    LOCAL_ALIGNED_32(int32_t, filterPos, [SRC_PIXELS]);
+
+    // The dst parameter here is either int16_t or int32_t but we use void* to
+    // just cover both cases.
+    declare_func(void, void *c, void *dst, int dstW,
+                 const uint8_t *src, const int16_t *filter,
+                 const int32_t *filterPos, int filterSize);
+
+    ctx = sws_alloc_context();
+    if (sws_init_context(ctx, NULL, NULL) < 0)
+        fail();
+
+    randomize_buffers(src, SRC_PIXELS + MAX_FILTER_WIDTH - 1);
+
+    for (hpi = 0; hpi < HSCALE_PAIRS; hpi++) {
+        for (fsi = 0; fsi < FILTER_SIZES; fsi++) {
+            width = filter_sizes[fsi];
+
+            ctx->srcBpc = hscale_pairs[hpi][0];
+            ctx->dstBpc = hscale_pairs[hpi][1];
+            ctx->hLumFilterSize = ctx->hChrFilterSize = width;
+
+            for (i = 0; i < SRC_PIXELS; i++) {
+                filterPos[i] = i;
+
+                // These filter cofficients are chosen to try break two corner
+                // cases, namely:
+                //
+                // - Negative filter coefficients. The filters output signed
+                //   values, and it should be possible to end up with negative
+                //   output values.
+                //
+                // - Positive clipping. The hscale filter function has clipping
+                //   at (1<<15) - 1
+                //
+                // The coefficients sum to the 1.0 point for the hscale
+                // functions (1 << 14).
+
+                for (j = 0; j < width; j++) {
+                    filter[i * width + j] = -((1 << 14) / (width - 1));
+                }
+                filter[i * width + (rnd() % width)] = ((1 << 15) - 1);
+            }
+
+            for (i = 0; i < MAX_FILTER_WIDTH; i++) {
+                // These values should be unused in SIMD implementations but
+                // may still be read, random coefficients here should help show
+                // issues where they are used in error.
+
+                filter[SRC_PIXELS * width + i] = rnd();
+            }
+            ff_getSwsFunc(ctx);
+
+            if (check_func(ctx->hcScale, "hscale_%d_to_%d_width%d", ctx->srcBpc, ctx->dstBpc + 1, width)) {
+                memset(dst0, 0, SRC_PIXELS * sizeof(dst0[0]));
+                memset(dst1, 0, SRC_PIXELS * sizeof(dst1[0]));
+
+                call_ref(NULL, dst0, SRC_PIXELS, src, filter, filterPos, width);
+                call_new(NULL, dst1, SRC_PIXELS, src, filter, filterPos, width);
+                if (memcmp(dst0, dst1, SRC_PIXELS * sizeof(dst0[0])))
+                    fail();
+                bench_new(NULL, dst0, SRC_PIXELS, src, filter, filterPos, width);
+            }
+        }
+    }
+    sws_freeContext(ctx);
+}
+
+void checkasm_check_sw_scale(void)
+{
+    check_hscale();
+    report("hscale");
+}

tests/fate/checkasm.mak

@@ -24,6 +24,7 @@ FATE_CHECKASM = fate-checkasm-aacpsdsp                                  \
                 fate-checkasm-sbrdsp                                    \
                 fate-checkasm-synth_filter                              \
                 fate-checkasm-sw_rgb                                    \
+                fate-checkasm-sw_scale                                  \
                 fate-checkasm-v210dec                                   \
                 fate-checkasm-v210enc                                   \
                 fate-checkasm-vf_blend                                  \