/usr/share/systemtap/runtime/autoconf-constant-tsc.c is in systemtap-common 1.6-1ubuntu1.
This file is owned by root:root, with mode 0o644.
The actual contents of the file can be viewed below.
1 2 3 | #include <asm/cpufeature.h>
int x = X86_FEATURE_CONSTANT_TSC;
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