[FFmpeg-devel] [PATCH] avcodec/x86/mpegvideoenc_template: Disable dead code

Andreas Rheinhardt andreas.rheinhardt at outlook.com
Tue Sep 12 01:28:12 EEST 2023


Since bfb28b5ce89f3e950214b67ea95b45e3355c2caf the permutation
type FF_IDCT_PERM_SIMPLE is ARCH_X86_32-only. So use this
knowledge to disable code for it when not on ARCH_X86_32.

Signed-off-by: Andreas Rheinhardt <andreas.rheinhardt at outlook.com>
---
 libavcodec/x86/idctdsp_init.c          | 2 ++
 libavcodec/x86/mpegvideoenc_template.c | 3 ++-
 2 files changed, 4 insertions(+), 1 deletion(-)

diff --git a/libavcodec/x86/idctdsp_init.c b/libavcodec/x86/idctdsp_init.c
index f28a1ad744..2d165b975b 100644
--- a/libavcodec/x86/idctdsp_init.c
+++ b/libavcodec/x86/idctdsp_init.c
@@ -45,10 +45,12 @@ av_cold int ff_init_scantable_permutation_x86(uint8_t *idct_permutation,
     int i;
 
     switch (perm_type) {
+#if ARCH_X86_32
     case FF_IDCT_PERM_SIMPLE:
         for (i = 0; i < 64; i++)
             idct_permutation[i] = simple_mmx_permutation[i];
         return 1;
+#endif
     case FF_IDCT_PERM_SSE2:
         for (i = 0; i < 64; i++)
             idct_permutation[i] = (i & 0x38) | idct_sse2_row_perm[i & 7];
diff --git a/libavcodec/x86/mpegvideoenc_template.c b/libavcodec/x86/mpegvideoenc_template.c
index b5b0a5ffa2..5f013be7f5 100644
--- a/libavcodec/x86/mpegvideoenc_template.c
+++ b/libavcodec/x86/mpegvideoenc_template.c
@@ -225,7 +225,8 @@ static int RENAME(dct_quantize)(MpegEncContext *s,
     if(s->mb_intra) block[0]= level;
     else            block[0]= temp_block[0];
 
-    if (s->idsp.perm_type == FF_IDCT_PERM_SIMPLE) {
+    av_assert2(ARCH_X86_32 || s->idsp.perm_type != FF_IDCT_PERM_SIMPLE);
+    if (ARCH_X86_32 && s->idsp.perm_type == FF_IDCT_PERM_SIMPLE) {
         if(last_non_zero_p1 <= 1) goto end;
         block[0x08] = temp_block[0x01]; block[0x10] = temp_block[0x08];
         block[0x20] = temp_block[0x10];
-- 
2.34.1



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