summaryrefslogtreecommitdiff
path: root/sysdeps/x86/cacheinfo.h
diff options
context:
space:
mode:
Diffstat (limited to 'sysdeps/x86/cacheinfo.h')
-rw-r--r--sysdeps/x86/cacheinfo.h9
1 files changed, 9 insertions, 0 deletions
diff --git a/sysdeps/x86/cacheinfo.h b/sysdeps/x86/cacheinfo.h
index eba8dbc4a6..41d2c81369 100644
--- a/sysdeps/x86/cacheinfo.h
+++ b/sysdeps/x86/cacheinfo.h
@@ -49,6 +49,11 @@ long int __x86_rep_stosb_threshold attribute_hidden = 2048;
/* Threshold to stop using Enhanced REP MOVSB. */
long int __x86_rep_movsb_stop_threshold attribute_hidden;
+/* A bit-wise OR of string/memory requirements for optimal performance
+ e.g. X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB. These bits
+ are used at runtime to tune implementation behavior. */
+int __x86_string_control attribute_hidden;
+
static void
init_cacheinfo (void)
{
@@ -71,5 +76,9 @@ init_cacheinfo (void)
__x86_rep_movsb_threshold = cpu_features->rep_movsb_threshold;
__x86_rep_stosb_threshold = cpu_features->rep_stosb_threshold;
__x86_rep_movsb_stop_threshold = cpu_features->rep_movsb_stop_threshold;
+
+ if (CPU_FEATURES_ARCH_P (cpu_features, Avoid_Short_Distance_REP_MOVSB))
+ __x86_string_control
+ |= X86_STRING_CONTROL_AVOID_SHORT_DISTANCE_REP_MOVSB;
}
#endif