Derive the SILDebugScope for a variable declaration from its owning ASTScope.

lib/SILGen/SILGenFunction.cpp

@@ -32,6 +32,7 @@
 #include "swift/AST/PropertyWrappers.h"
 #include "swift/AST/SourceFile.h"
 #include "swift/AST/Types.h"
+#include "swift/Basic/Defer.h"
 #include "swift/SIL/SILArgument.h"
 #include "swift/SIL/SILProfiler.h"
 #include "swift/SIL/SILUndef.h"
@@ -201,7 +202,17 @@ const SILDebugScope *SILGenFunction::getScopeOrNull(SILLocation Loc,
   SourceLoc SLoc = Loc.getSourceLoc();
   if (!SF || LastSourceLoc == SLoc)
     return nullptr;
-  return getOrCreateScope(SLoc);
+  // Prime VarDeclScopeMap.
+  auto Scope = getOrCreateScope(SLoc);
+  if (ForMetaInstruction)
+    if (ValueDecl *ValDecl = Loc.getAsASTNode<ValueDecl>()) {
+      // The source location of a VarDecl isn't necessarily in the same scope
+      // that the variable resides in for name lookup purposes.
+      auto ValueScope = VarDeclScopeMap.find(ValDecl);
+      if (ValueScope != VarDeclScopeMap.end())
+        return getOrCreateScope(ValueScope->second, F.getDebugScope());
+    }
+  return Scope;
 }
 
 const SILDebugScope *SILGenFunction::getOrCreateScope(SourceLoc SLoc) {
@@ -378,9 +389,14 @@ SILGenFunction::getOrCreateScope(const ast_scope::ASTScopeImpl *ASTScope,
   if (It != ScopeMap.end())
     return It->second;
 
-  LLVM_DEBUG( ASTScope->print(llvm::errs(), 0, false, false) );
+  LLVM_DEBUG(ASTScope->print(llvm::errs(), 0, false, false));
 
-  SILDebugScope *SILScope = nullptr;
+  auto cache = [&](const SILDebugScope *SILScope) {
+    ScopeMap.insert({{ASTScope, InlinedAt}, SILScope});
+    assert(SILScope->getParentFunction() == &F &&
+           "inlinedAt points to other function");
+    return SILScope;
+  };
 
   // Decide whether to pick a parent scope instead.
   if (ASTScope->ignoreInDebugInfo()) {
@@ -390,44 +406,68 @@ SILGenFunction::getOrCreateScope(const ast_scope::ASTScopeImpl *ASTScope,
     return ParentScope->InlinedCallSite != InlinedAt ? FnScope : ParentScope;
   }
 
+  // Collect all variable declarations in this scope.
+  struct Consumer : public namelookup::AbstractASTScopeDeclConsumer {
+    const ast_scope::ASTScopeImpl *ASTScope;
+    VarDeclScopeMapTy &VarDeclScopeMap;
+    Consumer(const ast_scope::ASTScopeImpl *ASTScope,
+             VarDeclScopeMapTy &VarDeclScopeMap)
+        : ASTScope(ASTScope), VarDeclScopeMap(VarDeclScopeMap) {}
+
+    bool consume(ArrayRef<ValueDecl *> values,
+                 NullablePtr<DeclContext> baseDC) override {
+      for (auto &value : values) {
+        assert(VarDeclScopeMap.count(value) == 0 && "VarDecl appears twice");
+        VarDeclScopeMap.insert({value, ASTScope});
+      }
+      return false;
+    }
+    bool lookInMembers(const DeclContext *) const override { return false; }
+#ifndef NDEBUG
+    void startingNextLookupStep() override {}
+    void finishingLookup(std::string) const override {}
+    bool isTargetLookup() const override { return false; }
+#endif
+  };
+  Consumer consumer(ASTScope, VarDeclScopeMap);
+  ASTScope->lookupLocalsOrMembers(consumer);
+
   // Collapse BraceStmtScopes whose parent is a .*BodyScope.
   if (auto Parent = ASTScope->getParent().getPtrOrNull())
     if (Parent->getSourceRangeOfThisASTNode() ==
         ASTScope->getSourceRangeOfThisASTNode())
-      return getOrCreateScope(Parent, FnScope, InlinedAt);
+      return cache(getOrCreateScope(Parent, FnScope, InlinedAt));
 
   // The calls to defer closures have cleanup source locations pointing to the
   // defer. Reparent them into the current debug scope.
   auto *AncestorScope = ASTScope->getParent().getPtrOrNull();
   while (AncestorScope && AncestorScope != FnASTScope &&
          !ScopeMap.count({AncestorScope, InlinedAt})) {
     if (auto *FD = dyn_cast_or_null<FuncDecl>(
-          AncestorScope->getDeclIfAny().getPtrOrNull())) {
+            AncestorScope->getDeclIfAny().getPtrOrNull())) {
       if (cast<DeclContext>(FD) != FunctionDC)
-        return B.getCurrentDebugScope();
+        return cache(B.getCurrentDebugScope());
 
       // This is this function's own scope.
       // If this is the outermost BraceStmt scope, ignore it.
       if (AncestorScope == ASTScope->getParent().getPtrOrNull())
-        return FnScope;
+        return cache(FnScope);
       break;
     }
 
     AncestorScope = AncestorScope->getParent().getPtrOrNull();
   };
 
+  // Create the scope and recursively its parents.  getLookupParent implements a
+  // special case for GuardBlockStmt, which is nested incorrectly.
+  auto *ParentScope = ASTScope->getLookupParent().getPtrOrNull();
   const SILDebugScope *Parent =
-    getOrCreateScope(ASTScope->getParent().getPtrOrNull(), FnScope, InlinedAt);
+      getOrCreateScope(ParentScope, FnScope, InlinedAt);
   SourceLoc SLoc = ASTScope->getSourceRangeOfThisASTNode().Start;
   RegularLocation Loc(SLoc);
-  SILScope = new (SGM.M)
+  auto *SILScope = new (SGM.M)
       SILDebugScope(Loc, FnScope->getParentFunction(), Parent, InlinedAt);
-  ScopeMap.insert({{ASTScope, InlinedAt}, SILScope});
-
-  assert(SILScope->getParentFunction() == &F &&
-         "inlinedAt points to other function");
-
-  return SILScope;
+  return cache(SILScope);
 }
 
 void SILGenFunction::enterDebugScope(SILLocation Loc, bool isBindingScope) {

lib/SILGen/SILGenFunction.h

@@ -366,6 +366,10 @@ class LLVM_LIBRARY_VISIBILITY SILGenFunction
   SourceLoc LastSourceLoc;
   using ASTScopeTy = ast_scope::ASTScopeImpl;
   const ASTScopeTy *FnASTScope = nullptr;
+  using VarDeclScopeMapTy =
+      llvm::SmallDenseMap<ValueDecl *, const ASTScopeTy *, 8>;
+  /// The ASTScope each variable declaration belongs to.
+  VarDeclScopeMapTy VarDeclScopeMap;
   /// Caches one SILDebugScope for each ASTScope.
   llvm::SmallDenseMap<std::pair<const ASTScopeTy *, const SILDebugScope *>,
                       const SILDebugScope *, 16>

test/DebugInfo/for-scope.swift

@@ -8,14 +8,15 @@ public func f(_ xs: [String?]) {
     sink(x)
   }
 }
+
 // CHECK: sil_scope [[F:[0-9]+]] { loc "{{.*}}":5:13 parent @$s1a1fyySaySSSgGF
-// CHECK: sil_scope [[S0:[0-9]+]] { loc "{{.*}}":6:3 parent [[F]] }
-// CHECK: sil_scope [[S1:[0-9]+]] { loc "{{.*}}":6:15 parent [[S0]] }
-// CHECK: sil_scope [[S3:[0-9]+]] { loc "{{.*}}":7:9 parent [[S1]] }
-// CHECK: sil_scope [[S4:[0-9]+]] { loc "{{.*}}":7:13 parent [[S3]] }
+// CHECK: sil_scope [[S3:[0-9]+]] { loc "{{.*}}":6:3 parent [[F]] }
+// CHECK: sil_scope [[S4:[0-9]+]] { loc "{{.*}}":6:15 parent [[S3]] }
+// CHECK: sil_scope [[S5:[0-9]+]] { loc "{{.*}}":7:13 parent [[S4]] }
+// CHECK: sil_scope [[S6:[0-9]+]] { loc "{{.*}}":7:9 parent [[S4]] }
 
-// CHECK: debug_value %[[X:.*]] : $Optional<String>, let, name "x", {{.*}}, scope [[S0]]
-// CHECK: retain_value %[[X]] : $Optional<String>, {{.*}}, scope [[S4]]
-// CHECK: debug_value %[[X1:[0-9]+]] : $String, let, name "x", {{.*}}, scope [[S3]]
-// CHECK:  release_value %[[X1]] : $String, {{.*}}, scope [[S3]]
-// CHECK:  release_value %[[X]] : $Optional<String>, {{.*}}, scope [[S3]]
+// CHECK: debug_value %[[X:.*]] : $Optional<String>, let, name "x", {{.*}}, scope [[S4]]
+// CHECK: retain_value %[[X]] : $Optional<String>, {{.*}}, scope [[S5]]
+// CHECK: debug_value %[[X1:[0-9]+]] : $String, let, name "x", {{.*}}, scope [[S6]]
+// CHECK:  release_value %[[X1]] : $String, {{.*}}, scope [[S6]]
+// CHECK:  release_value %[[X]] : $Optional<String>, {{.*}}, scope [[S6]]

test/DebugInfo/guard-let-scope.swift

@@ -7,13 +7,13 @@ func f(c: AnyObject??) {
   guard let x = x, let x = x else {
   // CHECK: sil_scope [[S3:[0-9]+]] { {{.*}} parent @{{.*}}1f
   // CHECK: sil_scope [[S4:[0-9]+]] { {{.*}} parent [[S3]] }
-  // CHECK: sil_scope [[S5:[0-9]+]] { {{.*}} parent [[S4]] }
-  // CHECK: sil_scope [[S6:[0-9]+]] { loc "{{.*}}":7:3 parent [[S4]] }
+  // CHECK: sil_scope [[S5:[0-9]+]] { {{.*}} parent [[S3]] }
+  // CHECK: sil_scope [[S6:[0-9]+]] { loc "{{.*}}":7:3 parent [[S5]] }
   // CHECK: sil_scope [[S7:[0-9]+]] { loc "{{.*}}":7:17 parent [[S6]] }
   // CHECK: sil_scope [[S8:[0-9]+]] { loc "{{.*}}":7:28 parent [[S7]] }
-  // CHECK: debug_value %{{.*}} : $Optional<Optional<AnyObject>>, let, name "x"{{.*}} scope [[S4]]
-  // CHECK: debug_value %{{.*}} : $Optional<AnyObject>, let, name "x", {{.*}} scope [[S6]]
-  // CHECK: debug_value %{{.*}} : $AnyObject, let, name "x", {{.*}} scope [[S7]]
+  // CHECK: debug_value %{{.*}} : $Optional<Optional<AnyObject>>, let, name "x"{{.*}} scope [[S5]]
+  // CHECK: debug_value %{{.*}} : $Optional<AnyObject>, let, name "x", {{.*}} scope [[S7]]
+  // CHECK: debug_value %{{.*}} : $AnyObject, let, name "x", {{.*}} scope [[S8]]
     fatalError()
   }
   // CHECK: function_ref {{.*3use.*}} scope [[S8]]

test/DebugInfo/guard-let-scope2.swift

@@ -18,7 +18,7 @@ public func f(x: String?) throws {
   }
   // CHECK: sil_scope [[S1:[0-9]+]] { {{.*}} parent @{{.*}}1f
   // CHECK: sil_scope [[S2:[0-9]+]] { {{.*}} parent [[S1]] }
-  // CHECK: sil_scope [[S3:[0-9]+]] { {{.*}} parent [[S2]] }
+  // CHECK: sil_scope [[S3:[0-9]+]] { {{.*}} parent [[S1]] }
   // CHECK: sil_scope [[S4:[0-9]+]] { {{.*}} parent [[S2]] }
   // CHECK: alloc_stack {{.*}} $SomeObject, let, name "s", {{.*}} scope [[S4]]
   guard let s = s else {

test/DebugInfo/guard-let-scope3.swift

@@ -7,12 +7,15 @@ public class S {
   private var c = [Int : C?]()
   public func f(_ i: Int) throws  -> C {
     guard let x = c[i], let x else {
-    // CHECK: sil_scope [[X1:[0-9]+]] { loc "{{.*}}":[[@LINE-1]]:5
-    // CHECK: sil_scope [[X2:[0-9]+]] { loc "{{.*}}":[[@LINE-2]]:29
-    // CHECK: debug_value {{.*}} : $Optional<C>, let, name "x", {{.*}}, scope [[X1]]
-    // CHECK: debug_value %29 : $C, let, name "x", {{.*}}, scope [[X2]]
-    // CHECK-NEXT:  scope [[X2]]
+      // CHECK: sil_scope [[P:[0-9]+]] { loc "{{.*}}":[[@LINE-1]]:5
+      // CHECK: sil_scope [[X1:[0-9]+]] { loc "{{.*}}":[[@LINE-2]]:19 parent [[P]]
+      // CHECK: sil_scope [[X2:[0-9]+]] { loc "{{.*}}":[[@LINE-3]]:29 parent [[X1]]
+      // CHECK: sil_scope [[GUARD:[0-9]+]] { loc "{{.*}}":[[@LINE-4]]:36 parent [[P]]
+      // CHECK: debug_value {{.*}} : $Optional<C>, let, name "x", {{.*}}, scope [[X1]]
+      // CHECK: debug_value {{.*}} : $C, let, name "x", {{.*}}, scope [[X2]]
+      // CHECK-NEXT:  scope [[X2]]
       throw MyError()
+      // CHECK: function_ref {{.*}}MyError{{.*}}:[[@LINE-1]]:13, scope [[GUARD]]
     }
     return x
   }

test/DebugInfo/if-let-scope.swift

@@ -0,0 +1,13 @@
+// RUN: %target-swift-frontend -g -emit-sil %s -parse-as-library -module-name a | %FileCheck %s
+func use<T>(_ t: T) {}
+public func f(value: String?) {
+  // CHECK: sil_scope [[S0:[0-9]+]] { loc "{{.*}}":[[@LINE-1]]:13
+  if let value, let value = Int(value) {
+    // CHECK: sil_scope [[S1:[0-9]+]] { loc "{{.*}}":[[@LINE-1]]:10
+    // CHECK: sil_scope [[S2:[0-9]+]] { loc "{{.*}}":[[@LINE-2]]:29 parent [[S1]] }
+    // CHECK: debug_value {{.*}} : $Optional<String>, let, name "value", {{.*}}, scope [[S0]]
+    // CHECK: debug_value {{.*}} : $String, let, name "value", {{.*}}, scope [[S1]]
+    // CHECK: debug_value {{.*}} : $Int, let, name "value", {{.*}}, scope [[S2]]
+    use((value))
+  }
+}

test/DebugInfo/inlinescopes.swift

@@ -27,10 +27,9 @@ func inlined(_ x: Int64) -> Int64 {
   let result = transparent(x)
 // CHECK-DAG: ![[CALL]] = !DILocation(line: [[@LINE-1]], column: {{.*}}, scope: ![[INLINED1:.*]], inlinedAt: ![[INLINEDAT:.*]])
 // CHECK-DAG: ![[INLINEDAT]] = !DILocation({{.*}}scope: ![[INLINEDAT1:[0-9]+]]
-// CHECK-DAG: ![[INLINED1]] = distinct !DILexicalBlock(scope: ![[INLINED2:[0-9]+]]
-// CHECK-DAG: ![[INLINED2]] = distinct !DILexicalBlock(scope: ![[INLINED3:[0-9]+]]
+// CHECK-DAG: ![[INLINED1]] = distinct !DILexicalBlock(scope: ![[INLINED:[0-9]+]]
 // Check if the inlined and removed function still has the correct linkage name.
-// CHECK-DAG: ![[INLINED3]] = distinct !DISubprogram(name: "inlined", linkageName: "$s4main7inlinedys5Int64VADF"
+// CHECK-DAG: ![[INLINED]] = distinct !DISubprogram(name: "inlined", linkageName: "$s4main7inlinedys5Int64VADF"
 // TRANSPARENT-CHECK-NOT: !DISubprogram(name: "transparent"
   return result
 }

test/DebugInfo/let-scope.swift

@@ -0,0 +1,8 @@
+// RUN: %target-swift-frontend -g -emit-sil %s -parse-as-library -module-name a | %FileCheck %s
+func use<T>(_ t: T) {}
+public func f(value: (Int, Int)) {
+  let (x, y) = value
+  // CHECK: debug_value {{.*}}let, name "x", {{.*}}, scope [[LET:[0-9]+]]
+  // CHECK: debug_value {{.*}}let, name "y", {{.*}}, scope [[LET]]
+  use((x,y))
+}

test/DebugInfo/shadowed-arg.swift

@@ -17,5 +17,6 @@ public func f(i: Int) {
 // CHECK: ![[S3]] = distinct !DILexicalBlock(scope: ![[S1]],
 // SIL: sil_scope [[S1:[0-9]+]] { {{.*}} parent @$s4main1f1iySi_tF
 // SIL: sil_scope [[S2:[0-9]+]] { {{.*}} parent [[S1]] }
+// SIL: sil_scope [[S3:[0-9]+]] { {{.*}} parent [[S1]] }
 // SIL: debug_value %0 : $Int, let, name "i", argno 1,{{.*}}, scope [[S1]]
-// SIL: debug_value {{.*}} : $Array<Int>, let, name "i", {{.*}}, scope [[S2]]
+// SIL: debug_value {{.*}} : $Array<Int>, let, name "i", {{.*}}, scope [[S3]]

test/Macros/macro_expand_closure.swift

@@ -20,8 +20,7 @@ func multiStatementInference() -> Int {
 // The closure intruduced by the macro expansion should not contain any inline
 // locations, but instead point directly into the macro buffer.
 // CHECK-SIL: sil_scope [[S0:[0-9]+]] { loc "@__swiftmacro_9MacroUser23multiStatementInferenceSiyF0cD0fMf_.swift":1:1 parent @$s9MacroUser23multiStatementInferenceSiyFSiyXEfU_
-// CHECK-SIL: sil_scope [[S1:[0-9]+]] { loc "@__swiftmacro_9MacroUser23multiStatementInferenceSiyF0cD0fMf_.swift":2:7 parent [[S0]] }
-// CHECK-SIL: sil_scope [[S2:[0-9]+]] { loc "@__swiftmacro_9MacroUser23multiStatementInferenceSiyF0cD0fMf_.swift":2:14 parent [[S1]] }
+// CHECK-SIL: sil_scope [[S2:[0-9]+]] { loc "@__swiftmacro_9MacroUser23multiStatementInferenceSiyF0cD0fMf_.swift":2:14 parent [[S0]] }
 
 // CHECK-SIL: sil {{.*}} @$s9MacroUser23multiStatementInferenceSiyFSiyXEfU_
 // CHECK-SIL-NOT: return

test/SILOptimizer/capturepromotion-wrong-lexicalscope.swift

@@ -19,12 +19,12 @@
 // CHECK:   destroy_value [[BOX_COPY]] : ${ var Int }, loc {{.*}}:33:11, scope 4
 // CHECK:   [[CLOSURE:%[^,]+]] = partial_apply [callee_guaranteed] [[SPECIALIZED_F]]([[REGISTER_11]]) : $@convention(thin) (Int) -> Int, loc {{.*}}:33:11, scope 4
 // CHECK:   [[BORROW:%.*]] = begin_borrow [lexical] [[CLOSURE]]
-// CHECK:   debug_value [[BORROW]] : $@callee_guaranteed () -> Int, let, name "f", loc {{.*}}:33:7, scope 5
-// CHECK:   [[CLOSURE_COPY:%[^,]+]] = copy_value [[BORROW]] : $@callee_guaranteed () -> Int, loc {{.*}}:34:10, scope 5
+// CHECK:   debug_value [[BORROW]] : $@callee_guaranteed () -> Int, let, name "f", loc {{.*}}:33:7, scope 6
+// CHECK:   [[CLOSURE_COPY:%[^,]+]] = copy_value [[BORROW]] : $@callee_guaranteed () -> Int, loc {{.*}}:34:10, scope 6
 // There used to be an end_borrow here. We leave an emptyline here to preserve line numbers.
-// CHECK:   destroy_value [[CLOSURE]] : $@callee_guaranteed () -> Int, loc {{.*}}:35:1, scope 5
-// CHECK:   destroy_value [[BOX]] : ${ var Int }, loc {{.*}}:35:1, scope 5
-// CHECK:   return [[CLOSURE_COPY]] : $@callee_guaranteed () -> Int, loc {{.*}}:34:3, scope 5
+// CHECK:   destroy_value [[CLOSURE]] : $@callee_guaranteed () -> Int, loc {{.*}}:35:1, scope 6
+// CHECK:   destroy_value [[BOX]] : ${ var Int }, loc {{.*}}:35:1, scope 6
+// CHECK:   return [[CLOSURE_COPY]] : $@callee_guaranteed () -> Int, loc {{.*}}:34:3, scope 6
 // CHECK: }