loongarch: fixes fate-checkasm-sw_rgb failure

The reason for the failure is that the function yuv2rgb_1_c_template was modified
in 095f8038fa9180842cd38d4d61c7c47a02aad9ed. The corresponding functional test
was added in c601bb8df5ae896061c42dd0e23cea8fba938ecb. The code on loongarch was
not updated in a timely manner, resulting in the error.

Signed-off-by: yuanhecai <yuanhecai@loongson.cn>
Reviewed-by: yinshiyou-hf@loongson.cn
Signed-off-by: Michael Niedermayer <michael@niedermayer.cc>

libswscale/loongarch/output_lasx.c

@@ -637,7 +637,7 @@ yuv2rgb_1_template_lasx(SwsInternal *c, const int16_t *buf0,
     int len_count = (dstW + 1) >> 1;
     const void *r, *g, *b;
 
-    if (uvalpha < 2048) {
+    if (uvalpha == 0) {
         int count    = 0;
         int head = YUVRGB_TABLE_HEADROOM;
         __m256i headroom  = __lasx_xvreplgr2vr_h(head);
@@ -706,14 +706,17 @@ yuv2rgb_1_template_lasx(SwsInternal *c, const int16_t *buf0,
         const int16_t *ubuf1 = ubuf[1], *vbuf1 = vbuf[1];
         int count = 0;
         int HEADROOM = YUVRGB_TABLE_HEADROOM;
-        __m256i headroom    = __lasx_xvreplgr2vr_w(HEADROOM);
+        int uvalpha1 = 4096 - uvalpha;
+        __m256i headroom     = __lasx_xvreplgr2vr_w(HEADROOM);
+        __m256i uvalpha_tmp1 = __lasx_xvreplgr2vr_h(uvalpha1);
+        __m256i uvalpha_tmp  = __lasx_xvreplgr2vr_h(uvalpha);
 
         for (i = 0; i < len; i += 16) {
             int Y1, Y2, U, V;
             int i_dex = i << 1;
             int c_dex = count << 1;
             __m256i src_y, src_u0, src_v0, src_u1, src_v1;
-            __m256i y_l, y_h, u, v;
+            __m256i y_l, y_h, u, v, u_ev, v_od;
 
             DUP4_ARG2(__lasx_xvldx, buf0, i_dex, ubuf0, c_dex, vbuf0, c_dex,
                       ubuf1, c_dex, src_y, src_u0, src_v0, src_u1);
@@ -721,12 +724,14 @@ yuv2rgb_1_template_lasx(SwsInternal *c, const int16_t *buf0,
             src_u0 = __lasx_xvpermi_q(src_u0, src_v0, 0x02);
             src_u1 = __lasx_xvpermi_q(src_u1, src_v1, 0x02);
             src_y  = __lasx_xvsrari_h(src_y, 7);
-            u      = __lasx_xvaddwev_w_h(src_u0, src_u1);
-            v      = __lasx_xvaddwod_w_h(src_u0, src_u1);
+            u_ev   = __lasx_xvmulwev_w_h(src_u0, uvalpha_tmp1);
+            v_od   = __lasx_xvmulwod_w_h(src_u0, uvalpha_tmp1);
+            u      = __lasx_xvmaddwev_w_h(u_ev, src_u1, uvalpha_tmp);
+            v      = __lasx_xvmaddwod_w_h(v_od, src_u1, uvalpha_tmp);
             y_l    = __lasx_xvsllwil_w_h(src_y, 0);
             y_h    = __lasx_xvexth_w_h(src_y);
-            u      = __lasx_xvsrari_w(u, 8);
-            v      = __lasx_xvsrari_w(v, 8);
+            u      = __lasx_xvsrari_w(u, 19);
+            v      = __lasx_xvsrari_w(v, 19);
             u      = __lasx_xvadd_w(u, headroom);
             v      = __lasx_xvadd_w(v, headroom);
             WRITE_YUV2RGB(y_l, y_l, u, u, 0, 1, 0, 4);
@@ -738,32 +743,6 @@ yuv2rgb_1_template_lasx(SwsInternal *c, const int16_t *buf0,
             WRITE_YUV2RGB(y_h, y_h, u, u, 4, 5, 3, 7);
             WRITE_YUV2RGB(y_h, y_h, v, v, 6, 7, 3, 7);
         }
-        if (dstW - i >= 8) {
-            int Y1, Y2, U, V;
-            int i_dex = i << 1;
-            __m256i src_y, src_u0, src_v0, src_u1, src_v1;
-            __m256i uv;
-
-            src_y  = __lasx_xvldx(buf0, i_dex);
-            src_u0 = __lasx_xvldrepl_d((ubuf0 + count), 0);
-            src_v0 = __lasx_xvldrepl_d((vbuf0 + count), 0);
-            src_u1 = __lasx_xvldrepl_d((ubuf1 + count), 0);
-            src_v1 = __lasx_xvldrepl_d((vbuf1 + count), 0);
-
-            src_u0 = __lasx_xvilvl_h(src_u1, src_u0);
-            src_v0 = __lasx_xvilvl_h(src_v1, src_v0);
-            src_u0 = __lasx_xvpermi_q(src_u0, src_v0, 0x02);
-            src_y  = __lasx_xvsrari_h(src_y, 7);
-            uv     = __lasx_xvhaddw_w_h(src_u0, src_u0);
-            src_y  = __lasx_vext2xv_w_h(src_y);
-            uv     = __lasx_xvsrari_w(uv, 8);
-            uv     = __lasx_xvadd_w(uv, headroom);
-            WRITE_YUV2RGB(src_y, src_y, uv, uv, 0, 1, 0, 4);
-            WRITE_YUV2RGB(src_y, src_y, uv, uv, 2, 3, 1, 5);
-            WRITE_YUV2RGB(src_y, src_y, uv, uv, 4, 5, 2, 6);
-            WRITE_YUV2RGB(src_y, src_y, uv, uv, 6, 7, 3, 7);
-            i += 8;
-        }
         for (; count < len_count; count++) {
             int Y1 = (buf0[count * 2    ]         +  64) >> 7;
             int Y2 = (buf0[count * 2 + 1]         +  64) >> 7;

libswscale/loongarch/output_lsx.c

@@ -595,7 +595,7 @@ yuv2rgb_1_template_lsx(SwsInternal *c, const int16_t *buf0,
     int len_count = (dstW + 1) >> 1;
     const void *r, *g, *b;
 
-    if (uvalpha < 2048) {
+    if (uvalpha == 0) {
         int count    = 0;
         int head = YUVRGB_TABLE_HEADROOM;
         __m128i headroom  = __lsx_vreplgr2vr_h(head);
@@ -659,61 +659,46 @@ yuv2rgb_1_template_lsx(SwsInternal *c, const int16_t *buf0,
         const int16_t *ubuf1 = ubuf[1], *vbuf1 = vbuf[1];
         int count = 0;
         int HEADROOM = YUVRGB_TABLE_HEADROOM;
+        int uvalpha1 = 4096 - uvalpha;
         __m128i headroom    = __lsx_vreplgr2vr_w(HEADROOM);
+        __m128i uvalpha_tmp1 = __lsx_vreplgr2vr_h(uvalpha1);
+        __m128i uvalpha_tmp  = __lsx_vreplgr2vr_h(uvalpha);
 
         for (i = 0; i < len; i += 8) {
             int Y1, Y2, U, V;
             int i_dex = i << 1;
             int c_dex = count << 1;
             __m128i src_y, src_u0, src_v0, src_u1, src_v1;
-            __m128i y_l, y_h, u1, u2, v1, v2;
+            __m128i y_l, y_h, u1, u2, v1, v2, u_ev, v_od;
 
             DUP4_ARG2(__lsx_vldx, buf0, i_dex, ubuf0, c_dex, vbuf0, c_dex,
                       ubuf1, c_dex, src_y, src_u0, src_v0, src_u1);
             src_v1 = __lsx_vldx(vbuf1, c_dex);
             src_y  = __lsx_vsrari_h(src_y, 7);
-            u1      = __lsx_vaddwev_w_h(src_u0, src_u1);
-            v1      = __lsx_vaddwod_w_h(src_u0, src_u1);
-            u2      = __lsx_vaddwev_w_h(src_v0, src_v1);
-            v2      = __lsx_vaddwod_w_h(src_v0, src_v1);
+
+            u_ev    = __lsx_vmulwev_w_h(src_u0, uvalpha_tmp1);
+            v_od    = __lsx_vmulwod_w_h(src_u0, uvalpha_tmp1);
+            u1      = __lsx_vmaddwev_w_h(u_ev, src_u1, uvalpha_tmp);
+            v1      = __lsx_vmaddwod_w_h(v_od, src_u1, uvalpha_tmp);
+            u_ev    = __lsx_vmulwev_w_h(src_v0, uvalpha_tmp1);
+            v_od    = __lsx_vmulwod_w_h(src_v0, uvalpha_tmp1);
+            u2      = __lsx_vmaddwev_w_h(u_ev, src_v1, uvalpha_tmp);
+            v2      = __lsx_vmaddwod_w_h(v_od, src_v1, uvalpha_tmp);
+
             y_l     = __lsx_vsllwil_w_h(src_y, 0);
             y_h     = __lsx_vexth_w_h(src_y);
-            u1      = __lsx_vsrari_w(u1, 8);
-            v1      = __lsx_vsrari_w(v1, 8);
-            u2      = __lsx_vsrari_w(u2, 8);
-            v2      = __lsx_vsrari_w(v2, 8);
+            u1      = __lsx_vsrari_w(u1, 19);
+            v1      = __lsx_vsrari_w(v1, 19);
+            u2      = __lsx_vsrari_w(u2, 19);
+            v2      = __lsx_vsrari_w(v2, 19);
             u1      = __lsx_vadd_w(u1, headroom);
             v1      = __lsx_vadd_w(v1, headroom);
             u2      = __lsx_vadd_w(u2, headroom);
             v2      = __lsx_vadd_w(v2, headroom);
-            WRITE_YUV2RGB_LSX(y_l, y_l, u1, v1, 0, 1, 0, 0);
-            WRITE_YUV2RGB_LSX(y_l, y_l, u2, v2, 2, 3, 0, 0);
-            WRITE_YUV2RGB_LSX(y_h, y_h, u1, v1, 0, 1, 1, 1);
-            WRITE_YUV2RGB_LSX(y_h, y_h, u2, v2, 2, 3, 1, 1);
-        }
-        if (dstW - i >= 4) {
-            int Y1, Y2, U, V;
-            int i_dex = i << 1;
-            __m128i src_y, src_u0, src_v0, src_u1, src_v1;
-            __m128i uv;
-
-            src_y  = __lsx_vldx(buf0, i_dex);
-            src_u0 = __lsx_vldrepl_d((ubuf0 + count), 0);
-            src_v0 = __lsx_vldrepl_d((vbuf0 + count), 0);
-            src_u1 = __lsx_vldrepl_d((ubuf1 + count), 0);
-            src_v1 = __lsx_vldrepl_d((vbuf1 + count), 0);
-
-            src_u0 = __lsx_vilvl_h(src_u1, src_u0);
-            src_v0 = __lsx_vilvl_h(src_v1, src_v0);
-            src_y  = __lsx_vsrari_h(src_y, 7);
-            src_y  = __lsx_vsllwil_w_h(src_y, 0);
-            uv     = __lsx_vilvl_h(src_v0, src_u0);
-            uv     = __lsx_vhaddw_w_h(uv, uv);
-            uv     = __lsx_vsrari_w(uv, 8);
-            uv     = __lsx_vadd_w(uv, headroom);
-            WRITE_YUV2RGB_LSX(src_y, src_y, uv, uv, 0, 1, 0, 1);
-            WRITE_YUV2RGB_LSX(src_y, src_y, uv, uv, 2, 3, 2, 3);
-            i += 4;
+            WRITE_YUV2RGB_LSX(y_l, y_l, u1, u2, 0, 1, 0, 0);
+            WRITE_YUV2RGB_LSX(y_l, y_l, v1, v2, 2, 3, 0, 0);
+            WRITE_YUV2RGB_LSX(y_h, y_h, u1, u2, 0, 1, 1, 1);
+            WRITE_YUV2RGB_LSX(y_h, y_h, v1, v2, 2, 3, 1, 1);
         }
         for (; count < len_count; count++) {
             int Y1 = (buf0[count * 2    ]         +  64) >> 7;