[Index] Make the USRs more stable.

- Only include offsets with local (in function scope) symbols, where we don't encode scoping
- Only include the filename with non-system symbols. Presumably the system headers will not provide conflicting definitions.

rdar://15976823

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@201990 91177308-0d34-0410-b5e6-96231b3b80d8

6 files changed, 50 insertions, 37 deletions

diff --git a/lib/Index/USRGeneration.cpp b/lib/Index/USRGeneration.cpp
index d71f6d5acd..6d73ceefcb 100644
--- a/lib/Index/USRGeneration.cpp
+++ b/lib/Index/USRGeneration.cpp
@@ -80,10 +80,16 @@ public:
   void VisitUnresolvedUsingTypenameDecl(const UnresolvedUsingTypenameDecl *D) {
     IgnoreResults = true;
   }
-  
+
+  bool ShouldGenerateLocation(const NamedDecl *D);
+
+  bool isLocal(const NamedDecl *D) {
+    return D->getParentFunctionOrMethod() != 0;
+  }
+
   /// Generate the string component containing the location of the
   ///  declaration.
-  bool GenLoc(const Decl *D);
+  bool GenLoc(const Decl *D, bool IncludeOffset);
 
   /// String generation methods used both by the visitation methods
   /// and from other clients that want to directly generate USRs.  These
@@ -143,8 +149,13 @@ bool USRGenerator::EmitDeclName(const NamedDecl *D) {
   return startSize == endSize;
 }
 
-static inline bool ShouldGenerateLocation(const NamedDecl *D) {
-  return !D->isExternallyVisible();
+bool USRGenerator::ShouldGenerateLocation(const NamedDecl *D) {
+  if (D->isExternallyVisible())
+    return false;
+  if (D->getParentFunctionOrMethod())
+    return true;
+  const SourceManager &SM = Context->getSourceManager();
+  return !SM.isInSystemHeader(D->getLocation());
 }
 
 void USRGenerator::VisitDeclContext(const DeclContext *DC) {
@@ -168,7 +179,7 @@ void USRGenerator::VisitFieldDecl(const FieldDecl *D) {
 }
 
 void USRGenerator::VisitFunctionDecl(const FunctionDecl *D) {
-  if (ShouldGenerateLocation(D) && GenLoc(D))
+  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
     return;
 
   VisitDeclContext(D->getDeclContext());
@@ -229,7 +240,7 @@ void USRGenerator::VisitVarDecl(const VarDecl *D) {
   // VarDecls can be declared 'extern' within a function or method body,
   // but their enclosing DeclContext is the function, not the TU.  We need
   // to check the storage class to correctly generate the USR.
-  if (ShouldGenerateLocation(D) && GenLoc(D))
+  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
     return;
 
   VisitDeclContext(D->getDeclContext());
@@ -249,13 +260,13 @@ void USRGenerator::VisitVarDecl(const VarDecl *D) {
 
 void USRGenerator::VisitNonTypeTemplateParmDecl(
                                         const NonTypeTemplateParmDecl *D) {
-  GenLoc(D);
+  GenLoc(D, /*IncludeOffset=*/true);
   return;
 }
 
 void USRGenerator::VisitTemplateTemplateParmDecl(
                                         const TemplateTemplateParmDecl *D) {
-  GenLoc(D);
+  GenLoc(D, /*IncludeOffset=*/true);
   return;
 }
 
@@ -329,7 +340,7 @@ void USRGenerator::VisitObjCContainerDecl(const ObjCContainerDecl *D) {
       // We want to mangle in the location to uniquely distinguish them.
       if (CD->IsClassExtension()) {
         Out << "objc(ext)" << ID->getName() << '@';
-        GenLoc(CD);
+        GenLoc(CD, /*IncludeOffset=*/true);
       }
       else
         GenObjCCategory(ID->getName(), CD->getName());
@@ -378,7 +389,7 @@ void USRGenerator::VisitObjCPropertyImplDecl(const ObjCPropertyImplDecl *D) {
 void USRGenerator::VisitTagDecl(const TagDecl *D) {
   // Add the location of the tag decl to handle resolution across
   // translation units.
-  if (ShouldGenerateLocation(D) && GenLoc(D))
+  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
     return;
 
   D = D->getCanonicalDecl();
@@ -449,7 +460,7 @@ void USRGenerator::VisitTagDecl(const TagDecl *D) {
 }
 
 void USRGenerator::VisitTypedefDecl(const TypedefDecl *D) {
-  if (ShouldGenerateLocation(D) && GenLoc(D))
+  if (ShouldGenerateLocation(D) && GenLoc(D, /*IncludeOffset=*/isLocal(D)))
     return;
   const DeclContext *DC = D->getDeclContext();
   if (const NamedDecl *DCN = dyn_cast<NamedDecl>(DC))
@@ -459,11 +470,11 @@ void USRGenerator::VisitTypedefDecl(const TypedefDecl *D) {
 }
 
 void USRGenerator::VisitTemplateTypeParmDecl(const TemplateTypeParmDecl *D) {
-  GenLoc(D);
+  GenLoc(D, /*IncludeOffset=*/true);
   return;
 }
 
-bool USRGenerator::GenLoc(const Decl *D) {
+bool USRGenerator::GenLoc(const Decl *D, bool IncludeOffset) {
   if (generatedLoc)
     return IgnoreResults;
   generatedLoc = true;
@@ -494,10 +505,12 @@ bool USRGenerator::GenLoc(const Decl *D) {
     IgnoreResults = true;
     return true;
   }
-  // Use the offest into the FileID to represent the location.  Using
-  // a line/column can cause us to look back at the original source file,
-  // which is expensive.
-  Out << '@' << Decomposed.second;
+  if (IncludeOffset) {
+    // Use the offest into the FileID to represent the location.  Using
+    // a line/column can cause us to look back at the original source file,
+    // which is expensive.
+    Out << '@' << Decomposed.second;
+  }
   return IgnoreResults;
 }
 
diff --git a/test/Index/annotate-comments-typedef.m b/test/Index/annotate-comments-typedef.m
index b23e53512c..751cfaab49 100644
--- a/test/Index/annotate-comments-typedef.m
+++ b/test/Index/annotate-comments-typedef.m
@@ -45,5 +45,5 @@ struct Foo1 {
 /** About Foo1T */
 typedef struct Foo1 Foo1T;
 // FIXME: we don't attach this comment to 'struct Foo1'
-// CHECK: TypedefDecl=Foo1T:[[@LINE-2]]:21 (Definition) {{.*}} FullCommentAsHTML=[<p class="para-brief"> About Foo1T </p>] FullCommentAsXML=[<Typedef file="{{[^"]+}}annotate-comments-typedef.m" line="[[@LINE-2]]" column="21"><Name>Foo1T</Name><USR>c:annotate-comments-typedef.m@{{[0-9]+}}@T@Foo1T</USR><Declaration>typedef struct Foo1 Foo1T</Declaration><Abstract><Para> About Foo1T </Para></Abstract></Typedef>]
+// CHECK: TypedefDecl=Foo1T:[[@LINE-2]]:21 (Definition) {{.*}} FullCommentAsHTML=[<p class="para-brief"> About Foo1T </p>] FullCommentAsXML=[<Typedef file="{{[^"]+}}annotate-comments-typedef.m" line="[[@LINE-2]]" column="21"><Name>Foo1T</Name><USR>c:annotate-comments-typedef.m@T@Foo1T</USR><Declaration>typedef struct Foo1 Foo1T</Declaration><Abstract><Para> About Foo1T </Para></Abstract></Typedef>]
 
diff --git a/test/Index/cxx11-lambdas.cpp b/test/Index/cxx11-lambdas.cpp
index 93db022035..afb540a84d 100644
--- a/test/Index/cxx11-lambdas.cpp
+++ b/test/Index/cxx11-lambdas.cpp
@@ -26,8 +26,8 @@ struct X {
 // RUN: env CINDEXTEST_INDEXLOCALSYMBOLS=1 c-index-test -index-file -std=c++11 %s | FileCheck -check-prefix=CHECK-INDEX %s
 // CHECK-INDEX: [indexEntityReference]: kind: variable | name: localA | USR: c:cxx11-lambdas.cpp@100@S@X@F@f#@localA | lang: C | cursor: VariableRef=localA:6:9 | loc: 7:21
 // CHECK-INDEX: [indexEntityReference]: kind: variable | name: localB | USR: c:cxx11-lambdas.cpp@100@S@X@F@f#@localB | lang: C | cursor: VariableRef=localB:6:17 | loc: 7:29
-// CHECK-INDEX: [indexEntityReference]: kind: typedef | name: Integer | USR: c:cxx11-lambdas.cpp@51@T@Integer | lang: C | cursor: TypeRef=Integer:3:13 | loc: 7:52
-// CHECK-INDEX: [indexEntityReference]: kind: typedef | name: Integer | USR: c:cxx11-lambdas.cpp@51@T@Integer | lang: C | cursor: TypeRef=Integer:3:13 | loc: 7:38
+// CHECK-INDEX: [indexEntityReference]: kind: typedef | name: Integer | USR: c:cxx11-lambdas.cpp@T@Integer | lang: C | cursor: TypeRef=Integer:3:13 | loc: 7:52
+// CHECK-INDEX: [indexEntityReference]: kind: typedef | name: Integer | USR: c:cxx11-lambdas.cpp@T@Integer | lang: C | cursor: TypeRef=Integer:3:13 | loc: 7:38
 // CHECK-INDEX: [indexEntityReference]: kind: variable | name: localA | USR: c:cxx11-lambdas.cpp@100@S@X@F@f#@localA | lang: C | cursor: DeclRefExpr=localA:6:9 | loc: 8:14
 // CHECK-INDEX: [indexEntityReference]: kind: variable | name: localB | USR: c:cxx11-lambdas.cpp@100@S@X@F@f#@localB | lang: C | cursor: DeclRefExpr=localB:6:17 | loc: 8:23
 // CHECK-INDEX: [indexEntityReference]: kind: variable | name: x | USR: c:cxx11-lambdas.cpp@157@S@X@F@f#@Ca@F@operator()#I#1@x | lang: C | cursor: DeclRefExpr=x:7:46 | loc: 8:32
diff --git a/test/Index/index-refs.cpp b/test/Index/index-refs.cpp
index 77e2af71f8..adbf02a7c6 100644
--- a/test/Index/index-refs.cpp
+++ b/test/Index/index-refs.cpp
@@ -102,7 +102,7 @@ void foo5() {
 
 // CHECK:      [indexDeclaration]: kind: c++-class-template | name: TS | {{.*}} | loc: 47:8
 // CHECK-NEXT: [indexDeclaration]: kind: struct-template-partial-spec | name: TS | USR: c:@SP>1#T@TS>#t0.0#I | {{.*}} | loc: 50:8
-// CHECK-NEXT: [indexDeclaration]: kind: typedef | name: MyInt | USR: c:index-refs.cpp@593@SP>1#T@TS>#t0.0#I@T@MyInt | {{.*}} | loc: 51:15 | semantic-container: [TS:50:8] | lexical-container: [TS:50:8]
+// CHECK-NEXT: [indexDeclaration]: kind: typedef | name: MyInt | USR: c:index-refs.cpp@SP>1#T@TS>#t0.0#I@T@MyInt | {{.*}} | loc: 51:15 | semantic-container: [TS:50:8] | lexical-container: [TS:50:8]
 /* when indexing implicit instantiations
   [indexDeclaration]: kind: struct-template-spec | name: TS | USR: c:@S@TS>#I | {{.*}} | loc: 50:8
   [indexDeclaration]: kind: typedef | name: MyInt | USR: c:index-refs.cpp@593@S@TS>#I@T@MyInt | {{.*}} | loc: 51:15 | semantic-container: [TS:50:8] | lexical-container: [TS:50:8]
diff --git a/test/Index/usrs.cpp b/test/Index/usrs.cpp
index e350f5cedf..909ce75922 100644
--- a/test/Index/usrs.cpp
+++ b/test/Index/usrs.cpp
@@ -85,7 +85,7 @@ void rdar9371763() {
 // CHECK: usrs.cpp c:@N@foo@F@bar#I# Extent=[3:3 - 3:18]
 // CHECK: usrs.cpp c:usrs.cpp@36@N@foo@F@bar#I#@z Extent=[3:12 - 3:17]
 // CHECK: usrs.cpp c:@N@bar Extent=[5:1 - 8:2]
-// CHECK: usrs.cpp c:usrs.cpp@64@N@bar@T@QType Extent=[6:3 - 6:20]
+// CHECK: usrs.cpp c:usrs.cpp@N@bar@T@QType Extent=[6:3 - 6:20]
 // CHECK: usrs.cpp c:@N@bar@F@bar#I# Extent=[7:3 - 7:20]
 // CHECK: usrs.cpp c:usrs.cpp@94@N@bar@F@bar#I#@z Extent=[7:12 - 7:19]
 // CHECK: usrs.cpp c:@C@ClsA Extent=[10:1 - 14:2]
@@ -101,13 +101,13 @@ void rdar9371763() {
 // CHECK: usrs.cpp c:@N@foo@C@ClsB@F@ClsB# Extent=[19:5 - 19:27]
 // CHECK: usrs.cpp c:@N@foo@C@ClsB@F@result#1 Extent=[20:5 - 20:23]
 // CHECK: usrs.cpp c:@N@foo@C@ClsB@F@result#1 Extent=[24:1 - 26:2]
-// CHECK: usrs.cpp c:usrs.cpp@360@aN@C@ClsC Extent=[29:3 - 29:35]
-// CHECK: usrs.cpp c:usrs.cpp@396@aN@w Extent=[30:3 - 30:8]
+// CHECK: usrs.cpp c:usrs.cpp@aN@C@ClsC Extent=[29:3 - 29:35]
+// CHECK: usrs.cpp c:usrs.cpp@aN@w Extent=[30:3 - 30:8]
 // CHECK: usrs.cpp c:@z Extent=[33:1 - 33:6]
 // CHECK: usrs.cpp c:@N@foo Extent=[35:1 - 40:2]
 // CHECK: usrs.cpp c:@N@foo@N@taz Extent=[35:17 - 39:2]
 // CHECK: usrs.cpp c:@N@foo@N@taz@x Extent=[36:3 - 36:8]
-// CHECK: usrs.cpp c:usrs.cpp@457@N@foo@N@taz@F@add#I#I# Extent=[37:3 - 37:56]
+// CHECK: usrs.cpp c:usrs.cpp@N@foo@N@taz@F@add#I#I# Extent=[37:3 - 37:56]
 // CHECK: usrs.cpp c:usrs.cpp@479@N@foo@N@taz@F@add#I#I#@a Extent=[37:25 - 37:30]
 // CHECK: usrs.cpp c:usrs.cpp@486@N@foo@N@taz@F@add#I#I#@b Extent=[37:32 - 37:37]
 // CHECK: usrs.cpp c:@N@foo@N@taz@F@sub#I#I# Extent=[38:3 - 38:25]
@@ -137,10 +137,10 @@ void rdar9371763() {
 // CHECK-NOT: ClsB
 // CHECK: usrs.cpp c:@NA@foo_alias3
 // CHECK: usrs.cpp c:@aN Extent=[68:1 - 73:2]
-// CHECK: usrs.cpp c:usrs.cpp@1097@aN@C@RDar9371763_Foo Extent=[69:1 - 72:2]
+// CHECK: usrs.cpp c:usrs.cpp@aN@C@RDar9371763_Foo Extent=[69:1 - 72:2]
 // CHECK: usrs.cpp c: Extent=[70:1 - 70:8]
-// CHECK: usrs.cpp c:usrs.cpp@1131@aN@C@RDar9371763_Foo@F@bar# Extent=[71:3 - 71:13]
-// CHECK: usrs.cpp c:usrs.cpp@1131@aN@C@RDar9371763_Foo@F@bar# Extent=[75:1 - 75:31]
+// CHECK: usrs.cpp c:usrs.cpp@aN@C@RDar9371763_Foo@F@bar# Extent=[71:3 - 71:13]
+// CHECK: usrs.cpp c:usrs.cpp@aN@C@RDar9371763_Foo@F@bar# Extent=[75:1 - 75:31]
 // CHECK: usrs.cpp c:@F@rdar9371763# Extent=[77:1 - 80:2]
 // CHECK: usrs.cpp c:usrs.cpp@1204@F@rdar9371763#@foo Extent=[78:3 - 78:22]
 
diff --git a/test/Index/usrs.m b/test/Index/usrs.m
index 0ba0e1afdf..c321e85196 100644
--- a/test/Index/usrs.m
+++ b/test/Index/usrs.m
@@ -90,19 +90,19 @@ int test_multi_declaration(void) {
 @end
 
 // RUN: c-index-test -test-load-source-usrs all -target x86_64-apple-macosx10.7 %s | FileCheck %s
-// CHECK: usrs.m c:usrs.m@67@F@my_helper Extent=[3:1 - 3:60]
+// CHECK: usrs.m c:usrs.m@F@my_helper Extent=[3:1 - 3:60]
 // CHECK: usrs.m c:usrs.m@95@F@my_helper@x Extent=[3:29 - 3:34]
 // CHECK: usrs.m c:usrs.m@102@F@my_helper@y Extent=[3:36 - 3:41]
-// CHECK: usrs.m c:usrs.m@128@Ea Extent=[5:1 - 8:2]
-// CHECK: usrs.m c:usrs.m@128@Ea@ABA Extent=[6:3 - 6:6]
-// CHECK: usrs.m c:usrs.m@128@Ea@CADABA Extent=[7:3 - 7:9]
-// CHECK: usrs.m c:usrs.m@155@Ea Extent=[10:1 - 13:2]
-// CHECK: usrs.m c:usrs.m@155@Ea@FOO Extent=[11:3 - 11:6]
-// CHECK: usrs.m c:usrs.m@155@Ea@BAR Extent=[12:3 - 12:6]
+// CHECK: usrs.m c:usrs.m@Ea Extent=[5:1 - 8:2]
+// CHECK: usrs.m c:usrs.m@Ea@ABA Extent=[6:3 - 6:6]
+// CHECK: usrs.m c:usrs.m@Ea@CADABA Extent=[7:3 - 7:9]
+// CHECK: usrs.m c:usrs.m@Ea Extent=[10:1 - 13:2]
+// CHECK: usrs.m c:usrs.m@Ea@FOO Extent=[11:3 - 11:6]
+// CHECK: usrs.m c:usrs.m@Ea@BAR Extent=[12:3 - 12:6]
 // CHECK: usrs.m c:@SA@MyStruct Extent=[15:9 - 18:2]
 // CHECK: usrs.m c:@SA@MyStruct@FI@wa Extent=[16:3 - 16:9]
 // CHECK: usrs.m c:@SA@MyStruct@FI@moo Extent=[17:3 - 17:10]
-// CHECK: usrs.m c:usrs.m@179@T@MyStruct Extent=[15:1 - 18:11]
+// CHECK: usrs.m c:usrs.m@T@MyStruct Extent=[15:1 - 18:11]
 // CHECK: usrs.m c:@E@Pizza Extent=[20:1 - 23:2]
 // CHECK: usrs.m c:@E@Pizza@CHEESE Extent=[21:3 - 21:9]
 // CHECK: usrs.m c:@E@Pizza@MUSHROOMS Extent=[22:3 - 22:12]
@@ -123,7 +123,7 @@ int test_multi_declaration(void) {
 // CHECK: usrs.m c:usrs.m@470objc(cs)Foo(cm)kingkong@local_var Extent=[41:3 - 41:16]
 // CHECK: usrs.m c:objc(cs)Foo(py)d1 Extent=[44:1 - 44:15]
 // CHECK: usrs.m c:@z Extent=[47:1 - 47:6]
-// CHECK: usrs.m c:usrs.m@529@F@local_func Extent=[49:1 - 49:43]
+// CHECK: usrs.m c:usrs.m@F@local_func Extent=[49:1 - 49:43]
 // CHECK: usrs.m c:usrs.m@551@F@local_func@x Extent=[49:23 - 49:28]
 // CHECK: usrs.m c:objc(cs)CWithExt Extent=[51:1 - 53:5]
 // CHECK: usrs.m c:objc(cs)CWithExt(im)meth1 Extent=[52:1 - 52:14]