diff --git a/src/main.cpp b/src/main.cpp
index da263e1..247db05 100644
--- a/src/main.cpp
+++ b/src/main.cpp
@@ -1,3 +1,4 @@
+//https://bugs.llvm.org/show_bug.cgi?id=24232
 #ifndef DEBUG
 #define DEBUG
 #endif
@@ -6,17 +7,29 @@
 #include <iostream>
 #include "debug.h"
 
+bool checkInvariantTSC(){
+	uint64_t rdx; 
+	asm volatile (".intel_syntax noprefix\t\n" \
+				  "mov eax, 0x80000007\t\n"		\
+				  // 80000007H\t\n" 
+				  "cpuid\t\n" : "=d" (rdx)	);
+	bool iTSC = rdx & (1<<8);
+		 //"and edx, 10000000\n")
+	return iTSC;
+}	
 //static inline
 uint64_t rdtscp()// uint32_t & aux )
 {
     uint64_t raxlo,rdxho;
-    asm volatile ( "cpuid\n" \
+    asm volatile ( ".intel_syntax noprefix\t\n"
+				   "cpuid\n" \
 				   //"rdtscp\n" : "=a" (raxlo), "=d" (rdxho), "=c" (aux) : : );
 				   "rdtsc\n" : "=a" (raxlo), "=d" (rdxho));
-    return (rdxho << 32) + raxlo;
+    return (rdxho << 32) + raxlo; //|
 }
 
 int main(int argc, char** argv){
+	log_debugcpp(checkInvariantTSC());
 	uint64_t test = rdtscp();
 	log_debugcpp(test);
 	return 0;