ASTScope: Remove source range sorting

Author: slavapestov

include/swift/AST/ASTScope.h

@@ -194,10 +194,6 @@ class ASTScopeImpl {
 #pragma mark - source ranges
 
 public:
-  /// Return signum of ranges. Centralize the invariant that ASTScopes use ends.
-  static int compare(SourceRange, SourceRange, const SourceManager &,
-                     bool ensureDisjoint);
-
   CharSourceRange getCharSourceRangeOfScope(SourceManager &SM,
                                             bool omitAssertions = false) const;
   bool isCharSourceRangeCached() const;

lib/AST/ASTScopeCreation.cpp

@@ -359,27 +359,6 @@ class ScopeCreator final {
     return culled;
   }
 
-  /// Templated to work on either ASTNodes, Decl*'s, or whatnot.
-  template <typename Rangeable>
-  std::vector<Rangeable>
-  sortBySourceRange(std::vector<Rangeable> toBeSorted) const {
-    auto compareNodes = [&](Rangeable n1, Rangeable n2) {
-      return isNotAfter(n1, n2);
-    };
-    std::stable_sort(toBeSorted.begin(), toBeSorted.end(), compareNodes);
-    return toBeSorted;
-  }
-
-  template <typename Rangeable>
-  bool isNotAfter(Rangeable n1, Rangeable n2) const {
-    const auto r1 = getRangeableSourceRange(n1);
-    const auto r2 = getRangeableSourceRange(n2);
-
-    const int signum = ASTScopeImpl::compare(r1, r2, ctx.SourceMgr,
-                                             /*ensureDisjoint=*/true);
-    return -1 == signum;
-  }
-
   SWIFT_DEBUG_DUMP { print(llvm::errs()); }
 
   void print(raw_ostream &out) const {
@@ -895,8 +874,7 @@ ASTSourceFileScope::expandAScopeThatCreatesANewInsertionPoint(
   std::vector<ASTNode> newNodes(decls.begin(), decls.end());
   insertionPoint =
       scopeCreator.addSiblingsToScopeTree(insertionPoint,
-                                          scopeCreator.sortBySourceRange(
-                                            scopeCreator.cull(newNodes)),
+                                          scopeCreator.cull(newNodes),
                                           endLoc);
 
   // Too slow to perform all the time:
@@ -1024,9 +1002,8 @@ BraceStmtScope::expandAScopeThatCreatesANewInsertionPoint(
   // elements in source order
   auto *insertionPoint =
       scopeCreator.addSiblingsToScopeTree(this,
-                                          scopeCreator.sortBySourceRange(
-                                            scopeCreator.cull(
-                                              stmt->getElements())),
+                                          scopeCreator.cull(
+                                            stmt->getElements()),
                                           endLoc);
   if (auto *s = scopeCreator.getASTContext().Stats)
     ++s->getFrontendCounters().NumBraceStmtASTScopeExpansions;
@@ -1388,7 +1365,7 @@ void GenericTypeOrExtensionScope::expandBody(ScopeCreator &) {}
 
 void IterableTypeScope::expandBody(ScopeCreator &scopeCreator) {
   auto nodes = asNodeVector(getIterableDeclContext().get()->getMembers());
-  nodes = scopeCreator.sortBySourceRange(scopeCreator.cull(nodes));
+  nodes = scopeCreator.cull(nodes);
   scopeCreator.addSiblingsToScopeTree(this, nodes, None);
   if (auto *s = scopeCreator.getASTContext().Stats)
     ++s->getFrontendCounters().NumIterableTypeBodyASTScopeExpansions;

lib/AST/ASTScopeSourceRange.cpp

@@ -371,35 +371,4 @@ SourceLoc ast_scope::extractNearestSourceLoc(
     std::tuple<ASTScopeImpl *, ScopeCreator *> scopeAndCreator) {
   const ASTScopeImpl *scope = std::get<0>(scopeAndCreator);
   return scope->getSourceRangeOfThisASTNode().Start;
-}
-
-int ASTScopeImpl::compare(const SourceRange lhs, const SourceRange rhs,
-                          const SourceManager &SM, const bool ensureDisjoint) {
-  ASTScopeAssert(!SM.isBeforeInBuffer(lhs.End, lhs.Start),
-                 "Range is backwards.");
-  ASTScopeAssert(!SM.isBeforeInBuffer(rhs.End, rhs.Start),
-                 "Range is backwards.");
-
-  auto cmpLoc = [&](const SourceLoc lhs, const SourceLoc rhs) {
-    return lhs == rhs ? 0 : SM.isBeforeInBuffer(lhs, rhs) ? -1 : 1;
-  };
-  // Establish that we use end locations throughout ASTScopes here
-  const int endOrder = cmpLoc(lhs.End, rhs.End);
-
-#ifndef NDEBUG
-  if (ensureDisjoint) {
-    const int startOrder = cmpLoc(lhs.Start, rhs.Start);
-
-    if (startOrder * endOrder == -1) {
-      llvm::errs() << "*** Start order contradicts end order between: ***\n";
-      lhs.print(llvm::errs(), SM, false);
-      llvm::errs() << "\n*** and: ***\n";
-      rhs.print(llvm::errs(), SM, false);
-    }
-    ASTScopeAssert(startOrder * endOrder != -1,
-                   "Start order contradicts end order");
-  }
-#endif
-
-  return endOrder;
-}
+}