[compiler-rt] r315306 - [XRay][compiler-rt] Fix rdtscp support check for x86_64

[Dean Michael Berris via llvm-commits]

Author: dberris
Date: Tue Oct 10 05:44:20 2017
New Revision: 315306

URL: http://llvm.org/viewvc/llvm-project?rev=315306&view=rev
Log:
[XRay][compiler-rt] Fix rdtscp support check for x86_64

Follow-up to D29438.

Modified:
    compiler-rt/trunk/lib/xray/xray_x86_64.cc

Modified: compiler-rt/trunk/lib/xray/xray_x86_64.cc
URL: http://llvm.org/viewvc/llvm-project/compiler-rt/trunk/lib/xray/xray_x86_64.cc?rev=315306&r1=315305&r2=315306&view=diff
==============================================================================
--- compiler-rt/trunk/lib/xray/xray_x86_64.cc (original)
+++ compiler-rt/trunk/lib/xray/xray_x86_64.cc Tue Oct 10 05:44:20 2017
@@ -258,9 +258,9 @@ bool probeRequiredCPUFeatures() XRAY_NEV
 
   // We check whether rdtscp support is enabled. According to the x86_64 manual,
   // level should be set at 0x80000001, and we should have a look at bit 27 in
-  // EDX. That's 0x8000000 (or 1u << 26).
+  // EDX. That's 0x8000000 (or 1u << 27).
   __get_cpuid(0x80000001, &EAX, &EBX, &ECX, &EDX);
-  if (!(EDX & (1u << 26))) {
+  if (!(EDX & (1u << 27))) {
     Report("Missing rdtscp support.\n");
     return false;
   }