x86: cabac: don't load/store context values in asm

Inspection of compiled code shows gcc handles these fine on its own.
Benchmarking also shows no measurable speed difference.

Removing the remaining cases in get_cabac_bypass_sign_x86() does
cause more substantial changes to the compiled code with uncertain
impact.

Signed-off-by: Mans Rullgard <mans@mansr.com>

1 files changed, 3 insertions, 9 deletions

diff --git a/libavcodec/x86/cabac.h b/libavcodec/x86/cabac.h
index 1ad74ff3e0..ae3f4b6e9e 100644
--- a/libavcodec/x86/cabac.h
+++ b/libavcodec/x86/cabac.h
@@ -87,19 +87,13 @@
 static av_always_inline int get_cabac_inline_x86(CABACContext *c,
                                                  uint8_t *const state)
 {
-    int bit, low, range, tmp;
+    int bit, tmp;
 
     __asm__ volatile(
-        "movl %a6(%5), %2               \n\t"
-        "movl %a7(%5), %1               \n\t"
         BRANCHLESS_GET_CABAC("%0", "%5", "(%4)", "%1", "%w1", "%2",
-                             "%3", "%b3", "%a8")
-        "movl %2, %a6(%5)               \n\t"
-        "movl %1, %a7(%5)               \n\t"
-
-        :"=&r"(bit), "=&r"(low), "=&r"(range), "=&q"(tmp)
+                             "%3", "%b3", "%a6")
+        :"=&r"(bit), "+&r"(c->low), "+&r"(c->range), "=&q"(tmp)
         :"r"(state), "r"(c),
-         "i"(offsetof(CABACContext, range)), "i"(offsetof(CABACContext, low)),
          "i"(offsetof(CABACContext, bytestream))
         : "%"REG_c, "memory"
     );