[FFmpeg-cvslog] avcodec/ppc/hevcdsp: Fix build failures with powerpc-linux-gnu-gcc-4.8 with --disable-optimizations

[Michael Niedermayer]

ffmpeg | branch: release/4.1 | Michael Niedermayer <michael at niedermayer.cc> | Tue Dec  4 16:29:40 2018 +0100| [55c36d2498119b3a01337115b28be006602ccb44] | committer: Michael Niedermayer

avcodec/ppc/hevcdsp: Fix build failures with powerpc-linux-gnu-gcc-4.8 with --disable-optimizations

The affected functions could also be changed into macros, this is the
smaller change to fix it though. And avoids (probably) less readable macros
The extra code should be optimized out when optimizations are done as all values
are known at build after inlining.

Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>
(cherry picked from commit 2c64a6bcd280c64997e6c4799bc89c0a9393bbf3)
Signed-off-by: Michael Niedermayer <michael at niedermayer.cc>

> http://git.videolan.org/gitweb.cgi/ffmpeg.git/?a=commit;h=55c36d2498119b3a01337115b28be006602ccb44
---

 libavcodec/ppc/hevcdsp.c | 17 +++++++++++++++--
 1 file changed, 15 insertions(+), 2 deletions(-)

diff --git a/libavcodec/ppc/hevcdsp.c b/libavcodec/ppc/hevcdsp.c
index dcae43305a..c1d562a409 100644
--- a/libavcodec/ppc/hevcdsp.c
+++ b/libavcodec/ppc/hevcdsp.c
@@ -58,7 +58,13 @@ static av_always_inline void transform4x4(vec_s16 src_01, vec_s16 src_23,
     e1 = vec_msums(src_02, trans4[2], zero);
     o1 = vec_msums(src_13, trans4[3], zero);
 
-    add = vec_sl(vec_splat_s32(1), vec_splat_u32(shift - 1));
+    switch(shift) {
+    case  7: add = vec_sl(vec_splat_s32(1), vec_splat_u32( 7 - 1)); break;
+    case 10: add = vec_sl(vec_splat_s32(1), vec_splat_u32(10 - 1)); break;
+    case 12: add = vec_sl(vec_splat_s32(1), vec_splat_u32(12 - 1)); break;
+    default: abort();
+    }
+
     e0 = vec_add(e0, add);
     e1 = vec_add(e1, add);
 
@@ -72,7 +78,14 @@ static av_always_inline void scale(vec_s32 res[4], vec_s16 res_packed[2],
                                    const int shift)
 {
     int i;
-    vec_u32 v_shift = vec_splat_u32(shift);
+    vec_u32 v_shift;
+
+    switch(shift) {
+    case  7: v_shift = vec_splat_u32(7) ; break;
+    case 10: v_shift = vec_splat_u32(10); break;
+    case 12: v_shift = vec_splat_u32(12); break;
+    default: abort();
+    }
 
     for (i = 0; i < 4; i++)
         res[i] = vec_sra(res[i], v_shift);