!3 = distinct !{} ; access group for instructions in the inner loop (which are implicitly contained in outer loop as well)
!4 = distinct !{} ; access group for instructions in the outer, but not the inner loop
+'``llvm.loop.mustprogress``' Metadata
+^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
+
+The ``llvm.loop.mustprogress`` metadata indicates that this loop is required to
+terminate, unwind, or interact with the environment in an observable way e.g.
+via a volatile memory access, I/O, or other synchronization. If such a loop is
+not found to interact with the environment in an observable way, the loop may
+be removed. This corresponds to the ``mustprogress`` function attribute.
+
'``irr_loop``' Metadata
^^^^^^^^^^^^^^^^^^^^^^^
/// unrolling pass is run more than once (which it generally is).
void setLoopAlreadyUnrolled();
+ /// Add llvm.loop.mustprogress to this loop's loop id metadata.
+ void setLoopMustProgress();
+
void dump() const;
void dumpVerbose() const;
setLoopID(NewLoopID);
}
+void Loop::setLoopMustProgress() {
+ LLVMContext &Context = getHeader()->getContext();
+
+ MDNode *MustProgress = findOptionMDForLoop(this, "llvm.loop.mustprogress");
+
+ if (MustProgress)
+ return;
+
+ MDNode *MustProgressMD =
+ MDNode::get(Context, MDString::get(Context, "llvm.loop.mustprogress"));
+ MDNode *LoopID = getLoopID();
+ MDNode *NewLoopID =
+ makePostTransformationMetadata(Context, LoopID, {}, {MustProgressMD});
+ setLoopID(NewLoopID);
+}
+
bool Loop::isAnnotatedParallel() const {
MDNode *DesiredLoopIdMetadata = getLoopID();