util: Force ESI register for cpuid's ebx result.

Fixes a segfault and better code. Unfortunately using an arbitrary
register ("=r") causes the gcc to abort when the code is optimized saying
it can't satisfy the constraint. Setting seems to do the trick.

diff --git a/src/gallium/auxiliary/util/u_cpu_detect.c b/src/gallium/auxiliary/util/u_cpu_detect.c
index 70ce25cfcf4c750aa608a6e00ba9d0f134cc00a2..ded361ce704bff59b93f6c8a3fe865d7c9c92d42 100644 (file)
--- a/src/gallium/auxiliary/util/u_cpu_detect.c
+++ b/src/gallium/auxiliary/util/u_cpu_detect.c
@@ -346,7 +346,7 @@ cpuid(uint32_t ax, uint32_t *p)
      "cpuid\n\t"
      "xchgl %%ebx, %1"
      : "=a" (p[0]),
-       "=m" (p[1]),
+       "=S" (p[1]),
        "=c" (p[2]),
        "=d" (p[3])
      : "0" (ax)