Remove uses of SIGILL for CPU extension detection, that method is not acceptable

in a library.
Should not change anything for PPC, the autodetection is currently pointless due
to other code being compiled with -maltivec as well (and detection for OSX and
AmigaOS remains in place).
SPARC binaries built with VIS support can now only run on systems with VIS.

Originally committed as revision 10648 to svn://svn.ffmpeg.org/ffmpeg/trunk

1 files changed, 3 insertions, 35 deletions

diff --git a/libavcodec/ppc/check_altivec.c b/libavcodec/ppc/check_altivec.c
index 72b4afe48a..b3778cab31 100644
--- a/libavcodec/ppc/check_altivec.c
+++ b/libavcodec/ppc/check_altivec.c
@@ -28,23 +28,6 @@
 #include <exec/exec.h>
 #include <interfaces/exec.h>
 #include <proto/exec.h>
-#else
-#include <signal.h>
-#include <setjmp.h>
-
-static sigjmp_buf jmpbuf;
-static volatile sig_atomic_t canjump = 0;
-
-static void sigill_handler (int sig)
-{
-    if (!canjump) {
-        signal (sig, SIG_DFL);
-        raise (sig);
-    }
-
-    canjump = 0;
-    siglongjmp (jmpbuf, 1);
-}
 #endif /* __APPLE__ */
 
 /**
@@ -72,24 +55,9 @@ int has_altivec(void)
     if (err == 0) return (has_vu != 0);
     return 0;
 #else
-/* Do it the brute-force way, borrowed from the libmpeg2 library. */
-    {
-      signal (SIGILL, sigill_handler);
-      if (sigsetjmp (jmpbuf, 1)) {
-        signal (SIGILL, SIG_DFL);
-      } else {
-        canjump = 1;
-
-        asm volatile ("mtspr 256, %0\n\t"
-                      "vand %%v0, %%v0, %%v0"
-                      :
-                      : "r" (-1));
-
-        signal (SIGILL, SIG_DFL);
-        return 1;
-      }
-    }
-    return 0;
+    // since we were compiled for altivec, just assume we have it
+    // until someone comes up with a proper way (not involving signal hacks).
+    return 1;
 #endif /* __AMIGAOS4__ */
 }