swscale/ppc: VSX-optimize hscale_fast

./ffmpeg -f lavfi -i yuvtestsrc=duration=1:size=1200x1440 -sws_flags fast_bilinear \
        -s 2400x720 -f rawvideo -vframes 5 -pix_fmt abgr -nostats test.raw

4.27 speedup for hyscale_fast:
  24796 UNITS in hyscale_fast,    4096 runs,      0 skips
   5797 UNITS in hyscale_fast,    4096 runs,      0 skips

4.48 speedup for hcscale_fast:
  19911 UNITS in hcscale_fast,    4095 runs,      1 skips
   4437 UNITS in hcscale_fast,    4096 runs,      0 skips

libswscale/ppc/swscale_vsx.c

@@ -1661,6 +1661,198 @@ YUV2PACKEDWRAPPER(yuv2, 422, yuyv422, AV_PIX_FMT_YUYV422)
 YUV2PACKEDWRAPPER(yuv2, 422, yvyu422, AV_PIX_FMT_YVYU422)
 YUV2PACKEDWRAPPER(yuv2, 422, uyvy422, AV_PIX_FMT_UYVY422)
 
+static void hyscale_fast_vsx(SwsContext *c, int16_t *dst, int dstWidth,
+                           const uint8_t *src, int srcW, int xInc)
+{
+    int i;
+    unsigned int xpos = 0, xx;
+    vector uint8_t vin, vin2, vperm;
+    vector int8_t vmul, valpha;
+    vector int16_t vtmp, vtmp2, vtmp3, vtmp4;
+    vector uint16_t vd_l, vd_r, vcoord16[2];
+    vector uint32_t vcoord[4];
+    const vector uint32_t vadd = (vector uint32_t) {
+        0,
+        xInc * 1,
+        xInc * 2,
+        xInc * 3,
+    };
+    const vector uint16_t vadd16 = (vector uint16_t) { // Modulo math
+        0,
+        xInc * 1,
+        xInc * 2,
+        xInc * 3,
+        xInc * 4,
+        xInc * 5,
+        xInc * 6,
+        xInc * 7,
+    };
+    const vector uint32_t vshift16 = vec_splats((uint32_t) 16);
+    const vector uint16_t vshift9 = vec_splat_u16(9);
+    const vector uint8_t vzero = vec_splat_u8(0);
+    const vector uint16_t vshift = vec_splat_u16(7);
+
+    for (i = 0; i < dstWidth; i += 16) {
+        vcoord16[0] = vec_splats((uint16_t) xpos);
+        vcoord16[1] = vec_splats((uint16_t) (xpos + xInc * 8));
+
+        vcoord16[0] = vec_add(vcoord16[0], vadd16);
+        vcoord16[1] = vec_add(vcoord16[1], vadd16);
+
+        vcoord16[0] = vec_sr(vcoord16[0], vshift9);
+        vcoord16[1] = vec_sr(vcoord16[1], vshift9);
+        valpha = (vector int8_t) vec_pack(vcoord16[0], vcoord16[1]);
+
+        xx = xpos >> 16;
+        vin = vec_vsx_ld(0, &src[xx]);
+
+        vcoord[0] = vec_splats(xpos & 0xffff);
+        vcoord[1] = vec_splats((xpos & 0xffff) + xInc * 4);
+        vcoord[2] = vec_splats((xpos & 0xffff) + xInc * 8);
+        vcoord[3] = vec_splats((xpos & 0xffff) + xInc * 12);
+
+        vcoord[0] = vec_add(vcoord[0], vadd);
+        vcoord[1] = vec_add(vcoord[1], vadd);
+        vcoord[2] = vec_add(vcoord[2], vadd);
+        vcoord[3] = vec_add(vcoord[3], vadd);
+
+        vcoord[0] = vec_sr(vcoord[0], vshift16);
+        vcoord[1] = vec_sr(vcoord[1], vshift16);
+        vcoord[2] = vec_sr(vcoord[2], vshift16);
+        vcoord[3] = vec_sr(vcoord[3], vshift16);
+
+        vcoord16[0] = vec_pack(vcoord[0], vcoord[1]);
+        vcoord16[1] = vec_pack(vcoord[2], vcoord[3]);
+        vperm = vec_pack(vcoord16[0], vcoord16[1]);
+
+        vin = vec_perm(vin, vin, vperm);
+
+        vin2 = vec_vsx_ld(1, &src[xx]);
+        vin2 = vec_perm(vin2, vin2, vperm);
+
+        vmul = (vector int8_t) vec_sub(vin2, vin);
+        vtmp = vec_mule(vmul, valpha);
+        vtmp2 = vec_mulo(vmul, valpha);
+        vtmp3 = vec_mergeh(vtmp, vtmp2);
+        vtmp4 = vec_mergel(vtmp, vtmp2);
+
+        vd_l = (vector uint16_t) vec_mergeh(vin, vzero);
+        vd_r = (vector uint16_t) vec_mergel(vin, vzero);
+        vd_l = vec_sl(vd_l, vshift);
+        vd_r = vec_sl(vd_r, vshift);
+
+        vd_l = vec_add(vd_l, (vector uint16_t) vtmp3);
+        vd_r = vec_add(vd_r, (vector uint16_t) vtmp4);
+
+        vec_st((vector int16_t) vd_l, 0, &dst[i]);
+        vec_st((vector int16_t) vd_r, 0, &dst[i + 8]);
+
+        xpos += xInc * 16;
+    }
+    for (i=dstWidth-1; (i*xInc)>>16 >=srcW-1; i--)
+        dst[i] = src[srcW-1]*128;
+}
+
+#define HCSCALE(in, out) \
+        vin = vec_vsx_ld(0, &in[xx]); \
+        vin = vec_perm(vin, vin, vperm); \
+\
+        vin2 = vec_vsx_ld(1, &in[xx]); \
+        vin2 = vec_perm(vin2, vin2, vperm); \
+\
+        vtmp = vec_mule(vin, valphaxor); \
+        vtmp2 = vec_mulo(vin, valphaxor); \
+        vtmp3 = vec_mergeh(vtmp, vtmp2); \
+        vtmp4 = vec_mergel(vtmp, vtmp2); \
+\
+        vtmp = vec_mule(vin2, valpha); \
+        vtmp2 = vec_mulo(vin2, valpha); \
+        vd_l = vec_mergeh(vtmp, vtmp2); \
+        vd_r = vec_mergel(vtmp, vtmp2); \
+\
+        vd_l = vec_add(vd_l, vtmp3); \
+        vd_r = vec_add(vd_r, vtmp4); \
+\
+        vec_st((vector int16_t) vd_l, 0, &out[i]); \
+        vec_st((vector int16_t) vd_r, 0, &out[i + 8])
+
+static void hcscale_fast_vsx(SwsContext *c, int16_t *dst1, int16_t *dst2,
+                           int dstWidth, const uint8_t *src1,
+                           const uint8_t *src2, int srcW, int xInc)
+{
+    int i;
+    unsigned int xpos = 0, xx;
+    vector uint8_t vin, vin2, vperm;
+    vector uint8_t valpha, valphaxor;
+    vector uint16_t vtmp, vtmp2, vtmp3, vtmp4;
+    vector uint16_t vd_l, vd_r, vcoord16[2];
+    vector uint32_t vcoord[4];
+    const vector uint8_t vxor = vec_splats((uint8_t) 127);
+    const vector uint32_t vadd = (vector uint32_t) {
+        0,
+        xInc * 1,
+        xInc * 2,
+        xInc * 3,
+    };
+    const vector uint16_t vadd16 = (vector uint16_t) { // Modulo math
+        0,
+        xInc * 1,
+        xInc * 2,
+        xInc * 3,
+        xInc * 4,
+        xInc * 5,
+        xInc * 6,
+        xInc * 7,
+    };
+    const vector uint32_t vshift16 = vec_splats((uint32_t) 16);
+    const vector uint16_t vshift9 = vec_splat_u16(9);
+
+    for (i = 0; i < dstWidth; i += 16) {
+        vcoord16[0] = vec_splats((uint16_t) xpos);
+        vcoord16[1] = vec_splats((uint16_t) (xpos + xInc * 8));
+
+        vcoord16[0] = vec_add(vcoord16[0], vadd16);
+        vcoord16[1] = vec_add(vcoord16[1], vadd16);
+
+        vcoord16[0] = vec_sr(vcoord16[0], vshift9);
+        vcoord16[1] = vec_sr(vcoord16[1], vshift9);
+        valpha = vec_pack(vcoord16[0], vcoord16[1]);
+        valphaxor = vec_xor(valpha, vxor);
+
+        xx = xpos >> 16;
+
+        vcoord[0] = vec_splats(xpos & 0xffff);
+        vcoord[1] = vec_splats((xpos & 0xffff) + xInc * 4);
+        vcoord[2] = vec_splats((xpos & 0xffff) + xInc * 8);
+        vcoord[3] = vec_splats((xpos & 0xffff) + xInc * 12);
+
+        vcoord[0] = vec_add(vcoord[0], vadd);
+        vcoord[1] = vec_add(vcoord[1], vadd);
+        vcoord[2] = vec_add(vcoord[2], vadd);
+        vcoord[3] = vec_add(vcoord[3], vadd);
+
+        vcoord[0] = vec_sr(vcoord[0], vshift16);
+        vcoord[1] = vec_sr(vcoord[1], vshift16);
+        vcoord[2] = vec_sr(vcoord[2], vshift16);
+        vcoord[3] = vec_sr(vcoord[3], vshift16);
+
+        vcoord16[0] = vec_pack(vcoord[0], vcoord[1]);
+        vcoord16[1] = vec_pack(vcoord[2], vcoord[3]);
+        vperm = vec_pack(vcoord16[0], vcoord16[1]);
+
+        HCSCALE(src1, dst1);
+        HCSCALE(src2, dst2);
+
+        xpos += xInc * 16;
+    }
+    for (i=dstWidth-1; (i*xInc)>>16 >=srcW-1; i--) {
+        dst1[i] = src1[srcW-1]*128;
+        dst2[i] = src2[srcW-1]*128;
+    }
+}
+
+#undef HCSCALE
+
 #endif /* !HAVE_BIGENDIAN */
 
 #endif /* HAVE_VSX */
@@ -1677,6 +1869,10 @@ av_cold void ff_sws_init_swscale_vsx(SwsContext *c)
 #if !HAVE_BIGENDIAN
     if (c->srcBpc == 8 && c->dstBpc <= 14) {
         c->hyScale = c->hcScale = hScale_real_vsx;
+        if (c->flags & SWS_FAST_BILINEAR && c->dstW >= c->srcW && c->chrDstW >= c->chrSrcW) {
+            c->hyscale_fast = hyscale_fast_vsx;
+            c->hcscale_fast = hcscale_fast_vsx;
+        }
     }
     if (!is16BPS(dstFormat) && !isNBPS(dstFormat) &&
         dstFormat != AV_PIX_FMT_NV12 && dstFormat != AV_PIX_FMT_NV21 &&