+RandomNumberGenerator *Module::createRNG(const Pass* P) const {
+ SmallString<32> Salt(P->getPassName());
+
+ // This RNG is guaranteed to produce the same random stream only
+ // when the Module ID and thus the input filename is the same. This
+ // might be problematic if the input filename extension changes
+ // (e.g. from .c to .bc or .ll).
+ //
+ // We could store this salt in NamedMetadata, but this would make
+ // the parameter non-const. This would unfortunately make this
+ // interface unusable by any Machine passes, since they only have a
+ // const reference to their IR Module. Alternatively we can always
+ // store salt metadata from the Module constructor.
+ Salt += sys::path::filename(getModuleIdentifier());
+
+ return new RandomNumberGenerator(Salt);
+}
+
+