[SymbolGraph] Make symbol-graph output deterministic

SymbolGraph generation iterating over llvm::DenseSet, which makes the
symbols and relationship fields appear in non-deterministic ordering.

Always sort the entries before serialization to make output
deterministic.

rdar://148839911

Author: cachemeifyoucan

lib/SymbolGraphGen/SymbolGraph.cpp

@@ -645,29 +645,31 @@ void SymbolGraph::serialize(llvm::json::OStream &OS) {
       symbolgraphgen::serialize(*ModuleVersion, OS);
     }
 
+    // Sort symbols for deterministic output.
+    SmallVector<Symbol> Symbols(Nodes.begin(), Nodes.end());
+    llvm::sort(Symbols, [](const Symbol &LHS, const Symbol &RHS) {
+      SmallString<256> LHSUSR, RHSUSR;
+      LHS.getUSR(LHSUSR);
+      RHS.getUSR(RHSUSR);
+      return LHSUSR < RHSUSR;
+    });
     OS.attributeArray("symbols", [&](){
-      for (const auto &S: Nodes) {
+      for (const auto &S: Symbols) {
         S.serialize(OS);
       }
     });
 
-#ifndef NDEBUG
-    // FIXME (solver-based-verification-sorting): In assert builds sort the
-    // edges so we get consistent symbol graph output. This allows us to compare
-    // the string representation of the symbolgraph between the solver-based
-    // and AST-based result.
-    // This can be removed once the AST-based cursor info has been removed.
-    SmallVector<Edge> Edges(this->Edges.begin(), this->Edges.end());
-    std::sort(Edges.begin(), Edges.end(), [](const Edge &LHS, const Edge &RHS) {
+    // Sort the edges so we get consistent symbol graph output.
+    SmallVector<Edge> OrderedEdges(Edges.begin(), Edges.end());
+    llvm::sort(OrderedEdges, [](const Edge &LHS, const Edge &RHS) {
       SmallString<256> LHSTargetUSR, RHSTargetUSR;
       LHS.Target.getUSR(LHSTargetUSR);
       RHS.Target.getUSR(RHSTargetUSR);
       return LHSTargetUSR < RHSTargetUSR;
     });
-#endif
 
     OS.attributeArray("relationships", [&](){
-      for (const auto &Relationship : Edges) {
+      for (const auto &Relationship : OrderedEdges) {
         Relationship.serialize(OS);
       }
     });

test/Frontend/output_determinism_check.swift

@@ -1,6 +1,6 @@
 // RUN: %empty-directory(%t)
 // RUN: echo '[]' > %t/protocol.json
-// RUN: %target-swift-frontend -module-name test -emit-module -o %t/test.swiftmodule %s -emit-module-doc-path %t/test.docc -const-gather-protocols-file %t/protocol.json -emit-const-values-path %t/test.swiftconstvalues -emit-tbd-path %t/test.tbd -tbd-current-version 1 -tbd-compatibility-version 1 -tbd-install_name @rpath/test.dylib -emit-loaded-module-trace -emit-loaded-module-trace-path %t/test.trace.json -enable-deterministic-check 2>&1 | %FileCheck %s --check-prefix=MODULE_OUTPUT --check-prefix=DOCC_OUTPUT --check-prefix=CONSTVALUE_OUTPUT --check-prefix=TBD_OUTPUT --check-prefix=TRACE_OUTPUT
+// RUN: %target-swift-frontend -module-name test -emit-module -o %t/test.swiftmodule %s -emit-module-doc-path %t/test.docc -const-gather-protocols-file %t/protocol.json -emit-const-values-path %t/test.swiftconstvalues -emit-symbol-graph -emit-symbol-graph-dir %t/symbols -emit-tbd-path %t/test.tbd -tbd-current-version 1 -tbd-compatibility-version 1 -tbd-install_name @rpath/test.dylib -emit-loaded-module-trace -emit-loaded-module-trace-path %t/test.trace.json -enable-deterministic-check 2>&1 | %FileCheck %s --check-prefix=MODULE_OUTPUT --check-prefix=DOCC_OUTPUT --check-prefix=CONSTVALUE_OUTPUT --check-prefix=TBD_OUTPUT --check-prefix=TRACE_OUTPUT --check-prefix=SYMBOLGRAPH_OUTPUT
 // RUN: %target-swift-frontend -module-name test -emit-sib -o %t/test.sib -primary-file %s -enable-deterministic-check 2>&1 | %FileCheck %s --check-prefix=SIB_OUTPUT
 
 /// object files are "not" deterministic because the second run going to match the mod hash and skip code generation.
@@ -22,6 +22,7 @@
 
 // RUN: %target-swift-frontend -emit-pcm -module-name UserClangModule -o %t/test.pcm %S/Inputs/dependencies/module.modulemap -enable-deterministic-check 2>&1 | %FileCheck %s --check-prefix=PCM_OUTPUT
 
+// SYMBOLGRAPH_OUTPUT: remark: produced matching output file '{{.*}}{{/|\\}}test.symbols.json'
 // DOCC_OUTPUT: remark: produced matching output file '{{.*}}{{/|\\}}test.docc'
 // CONSTVALUE_OUTPUT: remark: produced matching output file '{{.*}}{{/|\\}}test.swiftconstvalues'
 // MODULE_OUTPUT: remark: produced matching output file '{{.*}}{{/|\\}}test.swiftmodule'