[LAA] Tweak debug output for UTC stability (#140764)

UpdateTestChecks has a make_analyzer_generalizer to replace pointer
addressess from the debug output of LAA with a pattern, which is an
acceptable solution when there is one RUN line. However, when there are
multiple RUN lines with a common pattern, UTC fails to recognize common
output due to mismatched pointer addresses. Instead of hacking UTC scrub
the output before comparing the outputs from the different RUN lines,
fix the issue once and for all by making LAA not output unstable pointer
addresses in the first place.

The removal of the now-dead make_analyzer_generalizer is left as a
non-trivial exercise for a follow-up.

1 files changed, 16 insertions, 6 deletions

diff --git a/llvm/lib/Analysis/LoopAccessAnalysis.cpp b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
index 2a322a6..389c3c7 100644
--- a/llvm/lib/Analysis/LoopAccessAnalysis.cpp
+++ b/llvm/lib/Analysis/LoopAccessAnalysis.cpp
@@ -591,20 +591,29 @@ bool RuntimePointerChecking::needsChecking(unsigned I, unsigned J) const {
   return PointerI.AliasSetId == PointerJ.AliasSetId;
 }
 
+/// Assign each RuntimeCheckingPtrGroup pointer an index for stable UTC output.
+static DenseMap<const RuntimeCheckingPtrGroup *, unsigned>
+getPtrToIdxMap(ArrayRef<RuntimeCheckingPtrGroup> CheckingGroups) {
+  DenseMap<const RuntimeCheckingPtrGroup *, unsigned> PtrIndices;
+  for (const auto &[Idx, CG] : enumerate(CheckingGroups))
+    PtrIndices[&CG] = Idx;
+  return PtrIndices;
+}
+
 void RuntimePointerChecking::printChecks(
     raw_ostream &OS, const SmallVectorImpl<RuntimePointerCheck> &Checks,
     unsigned Depth) const {
   unsigned N = 0;
+  auto PtrIndices = getPtrToIdxMap(CheckingGroups);
   for (const auto &[Check1, Check2] : Checks) {
     const auto &First = Check1->Members, &Second = Check2->Members;
-
     OS.indent(Depth) << "Check " << N++ << ":\n";
-
-    OS.indent(Depth + 2) << "Comparing group (" << Check1 << "):\n";
+    OS.indent(Depth + 2) << "Comparing group GRP" << PtrIndices.at(Check1)
+                         << ":\n";
     for (unsigned K : First)
       OS.indent(Depth + 2) << *Pointers[K].PointerValue << "\n";
-
-    OS.indent(Depth + 2) << "Against group (" << Check2 << "):\n";
+    OS.indent(Depth + 2) << "Against group GRP" << PtrIndices.at(Check2)
+                         << ":\n";
     for (unsigned K : Second)
       OS.indent(Depth + 2) << *Pointers[K].PointerValue << "\n";
   }
@@ -616,8 +625,9 @@ void RuntimePointerChecking::print(raw_ostream &OS, unsigned Depth) const {
   printChecks(OS, Checks, Depth);
 
   OS.indent(Depth) << "Grouped accesses:\n";
+  auto PtrIndices = getPtrToIdxMap(CheckingGroups);
   for (const auto &CG : CheckingGroups) {
-    OS.indent(Depth + 2) << "Group " << &CG << ":\n";
+    OS.indent(Depth + 2) << "Group GRP" << PtrIndices.at(&CG) << ":\n";
     OS.indent(Depth + 4) << "(Low: " << *CG.Low << " High: " << *CG.High
                          << ")\n";
     for (unsigned Member : CG.Members) {