[Diagnostics] Emit generated code buffers into diagnostic files.

Extend the serialized diagnostics file format to also support providing
the contents of source files, which can include a reference to the
"original source range" whose text is conceptually replaced with the
contents of the serialized diagnostics file, e.g., due to macro
expansion.

Author: DougGregor

lib/Frontend/SerializedDiagnosticConsumer.cpp

@@ -188,7 +188,9 @@ class SerializedDiagnosticConsumer : public DiagnosticConsumer {
   }
 
   // Record identifier for the file.
-  unsigned getEmitFile(StringRef Filename);
+  unsigned getEmitFile(
+      SourceManager &SM, StringRef Filename, unsigned bufferID
+  );
 
   // Record identifier for the category.
   unsigned getEmitCategory(StringRef Category);
@@ -217,7 +219,9 @@ namespace serialized_diagnostics {
 } // namespace serialized_diagnostics
 } // namespace swift
 
-unsigned SerializedDiagnosticConsumer::getEmitFile(StringRef Filename) {
+unsigned SerializedDiagnosticConsumer::getEmitFile(
+    SourceManager &SM, StringRef Filename, unsigned bufferID
+) {
   // NOTE: Using Filename.data() here relies on SourceMgr using
   // const char* as buffer identifiers.  This is fast, but may
   // be brittle.  We can always switch over to using a StringMap.
@@ -238,6 +242,32 @@ unsigned SerializedDiagnosticConsumer::getEmitFile(StringRef Filename) {
   State->Stream.EmitRecordWithBlob(State->Abbrevs.get(RECORD_FILENAME),
                                    Record, Filename.data());
 
+  // If the buffer contains code that was synthesized by the compiler,
+  // emit the contents of the buffer.
+  auto generatedInfo = SM.getGeneratedSourceInfo(bufferID);
+  if (!generatedInfo)
+    return entry;
+
+  Record.clear();
+  Record.push_back(RECORD_SOURCE_FILE_CONTENTS);
+  Record.push_back(entry);
+
+  // The source range that this buffer was generated from, expressed as
+  // offsets into the original buffer.
+  auto originalFilename = SM.getDisplayNameForLoc(generatedInfo->originalSourceRange.Start);
+  addRangeToRecord(
+      Lexer::getCharSourceRangeFromSourceRange(
+          SM, generatedInfo->originalSourceRange),
+      SM, originalFilename, Record
+  );
+
+  // Contents of the buffer.
+  auto sourceText = SM.getEntireTextForBuffer(bufferID);
+  Record.push_back(sourceText.size());
+  State->Stream.EmitRecordWithBlob(
+      State->Abbrevs.get(RECORD_SOURCE_FILE_CONTENTS),
+      Record, sourceText);
+
   return entry;
 }
 
@@ -275,7 +305,7 @@ void SerializedDiagnosticConsumer::addLocToRecord(SourceLoc Loc,
   unsigned line, col;
   std::tie(line, col) = SM.getPresumedLineAndColumnForLoc(Loc);
 
-  Record.push_back(getEmitFile(Filename));
+  Record.push_back(getEmitFile(SM, Filename, bufferId));
   Record.push_back(line);
   Record.push_back(col);
   Record.push_back(SM.getLocOffsetInBuffer(Loc, bufferId));
@@ -411,6 +441,8 @@ void SerializedDiagnosticConsumer::emitBlockInfoBlock() {
   emitRecordID(RECORD_DIAG_FLAG, "DiagFlag", Stream, Record);
   emitRecordID(RECORD_FILENAME, "FileName", Stream, Record);
   emitRecordID(RECORD_FIXIT, "FixIt", Stream, Record);
+  emitRecordID(
+      RECORD_SOURCE_FILE_CONTENTS, "SourceFileContents", Stream, Record);
 
   // Emit abbreviation for RECORD_DIAG.
   Abbrev = std::make_shared<BitCodeAbbrev>();
@@ -467,6 +499,16 @@ void SerializedDiagnosticConsumer::emitBlockInfoBlock() {
   Abbrevs.set(RECORD_FIXIT, Stream.EmitBlockInfoAbbrev(BLOCK_DIAG,
                                                        Abbrev));
 
+  // Emit the abbreviation for RECORD_SOURCE_FILE_CONTENTS.
+  Abbrev = std::make_shared<BitCodeAbbrev>();
+  Abbrev->Add(BitCodeAbbrevOp(RECORD_SOURCE_FILE_CONTENTS));
+  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 10)); // File ID.
+  addRangeLocationAbbrev(Abbrev);
+  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Fixed, 16)); // File size.
+  Abbrev->Add(BitCodeAbbrevOp(BitCodeAbbrevOp::Blob)); // File contents.
+  Abbrevs.set(RECORD_SOURCE_FILE_CONTENTS,
+              Stream.EmitBlockInfoAbbrev(BLOCK_DIAG, Abbrev));
+
   Stream.ExitBlock();
 }
 

test/Macros/macro_expand.swift

@@ -1,7 +1,14 @@
 // RUN: %empty-directory(%t)
 // RUN: %target-build-swift -I %swift-host-lib-dir -L %swift-host-lib-dir -emit-library -o %t/%target-library-name(MacroDefinition) -module-name=MacroDefinition %S/Inputs/syntax_macro_definitions.swift -g -no-toolchain-stdlib-rpath
 // RUNx: %target-swift-frontend -dump-ast -enable-experimental-feature Macros -enable-experimental-feature Macros -load-plugin-library %t/%target-library-name(MacroDefinition) -I %swift-host-lib-dir %s -module-name MacroUser 2>&1 | %FileCheck --check-prefix CHECK-AST %s
+
+// Diagnostics testing
 // RUN: %target-typecheck-verify-swift -enable-experimental-feature Macros -load-plugin-library %t/%target-library-name(MacroDefinition) -I %swift-host-lib-dir -module-name MacroUser -DTEST_DIAGNOSTICS
+
+// RUN: not %target-swift-frontend -typecheck -enable-experimental-feature Macros -load-plugin-library %t/%target-library-name(MacroDefinition) -I %swift-host-lib-dir -module-name MacroUser -DTEST_DIAGNOSTICS -serialize-diagnostics-path %t/macro_expand.dia %s
+// RUN: c-index-test -read-diagnostics %t/macro_expand.dia 2>&1 | %FileCheck -check-prefix CHECK-DIAGS %s
+
+// Execution testing
 // RUN: %target-build-swift -enable-experimental-feature Macros -enable-experimental-feature Macros -load-plugin-library %t/%target-library-name(MacroDefinition) -I %swift-host-lib-dir -L %swift-host-lib-dir %s -o %t/main -module-name MacroUser
 // RUN: %target-run %t/main | %FileCheck %s
 // REQUIRES: executable_test
@@ -75,6 +82,11 @@ func testAddBlocker(a: Int, b: Int, c: Int, oa: OnlyAdds) {
   // expected-note@-1{{in expansion of macro 'addBlocker' here}}
   // expected-note@-2{{use '-'}}{{22-23=-}}
 
+  // CHECK-DIAGS: macro_expand.swift:81:7-81:27:1:4: error: binary operator '-' cannot be applied to two 'OnlyAdds' operands [] []
+  // CHECK-DIAGS: CONTENTS OF FILE{{.*}}addBlocker
+  // CHECK-DIAGS-NEXT: Original source range: {{.*}}macro_expand.swift:81:7 - {{.*}}macro_expand.swift:81:27
+  // CHECK-DIAGS-NEXT: oa - oa
+  // CHECK-DIAGS-NEXT: END CONTENTS OF FILE
   // Check recursion.
   #recurse(false) // okay
   #recurse(true) // expected-note{{in expansion of macro 'recurse' here}}