[SILProfiler] Add debug output for {push,pop}Region operations

Author: vedantk

lib/SIL/SILProfiler.cpp

@@ -430,6 +430,20 @@ class SourceMappingRegion {
     assert(EndLoc && "Region has no end location");
     return *EndLoc;
   }
+
+  void print(llvm::raw_ostream &OS, const SourceManager &SM) const {
+    OS << "[";
+    if (hasStartLoc())
+      getStartLoc().print(OS, SM);
+    else
+      OS << "?";
+    OS << ", ";
+    if (hasEndLoc())
+      getEndLoc().print(OS, SM);
+    else
+      OS << "?";
+    OS << "]";
+  }
 };
 
 /// An ASTWalker that maps ASTNodes to profiling counters.
@@ -754,6 +768,11 @@ struct CoverageMapping : public ASTWalker {
   void pushRegion(ASTNode Node) {
     RegionStack.emplace_back(Node, getCounter(Node), Node.getStartLoc(),
                              getEndLoc(Node));
+    LLVM_DEBUG({
+      llvm::dbgs() << "Pushed region: ";
+      RegionStack.back().print(llvm::dbgs(), SM);
+      llvm::dbgs() << "\n";
+    });
   }
 
   /// Replace the current region's count by pushing an incomplete region.
@@ -780,6 +799,8 @@ struct CoverageMapping : public ASTWalker {
     auto ParentIt = I;
     SourceLoc EndLoc = ParentIt->getEndLoc();
 
+    unsigned FirstPoppedIndex = SourceRegions.size();
+    (void)FirstPoppedIndex;
     SourceRegions.push_back(std::move(*I++));
     for (; I != E; ++I) {
       if (!I->hasStartLoc())
@@ -789,6 +810,14 @@ struct CoverageMapping : public ASTWalker {
       SourceRegions.push_back(std::move(*I));
     }
 
+    LLVM_DEBUG({
+      for (unsigned Idx = FirstPoppedIndex; Idx < SourceRegions.size(); ++Idx) {
+        llvm::dbgs() << "Popped region: ";
+        SourceRegions[Idx].print(llvm::dbgs(), SM);
+        llvm::dbgs() << "\n";
+      }
+    });
+
     RegionStack.erase(ParentIt, E);
   }