llvm-project/llvm/test/Regression/CodeGen/X86/rdtsc.ll

; RUN: llvm-as < %s | llc -march=x86 | grep rdtsc

declare ulong %llvm.readcyclecounter()

ulong %foo() {
%tmp.1 = call ulong %llvm.readcyclecounter ()
ret ulong %tmp.1
}