[modules] Print input files when -module-file-info file switch is passed.

[v.g.vassilev]

Summary

This patch improves traceability of duplicated header files which end up in multiple pcms.

[bruno]

Thanks for improving this Vassil. Where does in the output it shows up? I wonder if we should have those at the end given the huge amount of headers some modules might have.

[v.g.vassilev]

It looks like the diagnostic options and few others were moved out from the control block in r297655 by Manman Ren. The header files are still part of the control block. The best I can do is buffer that information and print it out last. Is that what we want?

[bruno]

It looks like the diagnostic options and few others were moved out from the control block in r297655 by Manman Ren. The header files are still part of the control block. The best I can do is buffer that information and print it out last. Is that what we want?

Your patch as is seems fine. We can go for the buffering the output later on if it proves hard to read.

cfe/trunk/lib/Frontend/FrontendActions.cpp

void readModuleFileExtension(
                     << "." << Metadata.MinorVersion;
       if (!Metadata.UserInfo.empty()) {
         Out << ": ";
         Out.write_escaped(Metadata.UserInfo);
       }
 
       Out << "\n";
     }
+
+    /// Tells the \c ASTReaderListener that we want to receive the
+    /// input files of the AST file via \c visitInputFile.
+    bool needsInputFileVisitation() override { return true; }
+
+    /// Tells the \c ASTReaderListener that we want to receive the
+    /// input files of the AST file via \c visitInputFile.
+    bool needsSystemInputFileVisitation() override { return true; }
+
+    /// Indicates that the AST file contains particular input file.
+    ///
+    /// \returns true to continue receiving the next input file, false to stop.
+    bool visitInputFile(StringRef Filename, bool isSystem,
+                        bool isOverridden, bool isExplicitModule) override {
+
+      Out.indent(2) << "Input file: " << Filename;
+
+      if (isSystem || isOverridden || isExplicitModule) {
+        Out << " [";
+        if (isSystem) {
+          Out << "System";
+          if (isOverridden || isExplicitModule)
+            Out << ", ";
+        }
+        if (isOverridden) {
+          Out << "Overridden";
+          if (isExplicitModule)
+            Out << ", ";
+        }
+        if (isExplicitModule)
+          Out << "ExplicitModule";
+
+        Out << "]";
+      }
+
+      Out << "\n";
+
+      return true;
+    }
 #undef DUMP_BOOLEAN
   };
 }
 
 bool DumpModuleInfoAction::BeginInvocation(CompilerInstance &CI) {
   // The Object file reader also supports raw ast files and there is no point in
   // being strict about the module file format in -module-file-info mode.
   CI.getHeaderSearchOpts().ModuleFormat = "obj";

cfe/trunk/test/Modules/module_file_info.m

 // CHECK:   Use libc++ (rather than libstdc++) [-stdlib=]:
 
 // CHECK: Preprocessor options:
 // CHECK:   Uses compiler/target-specific predefines [-undef]: Yes
 // CHECK:   Uses detailed preprocessing record (for indexing): No
 // CHECK:   Predefined macros:
 // CHECK:     -DBLARG
 // CHECK:     -DWIBBLE=WOBBLE
+// CHECK: Input file: {{.*}}DependsOnModulePrivate.h
+// CHECK-NEXT: Input file: {{.*}}Other.h
+// CHECK-NEXT: Input file: {{.*}}SubFramework.h
+// CHECK-NEXT: Input file: {{.*}}not_coroutines.h
+// CHECK-NEXT: Input file: {{.*}}not_cxx.h
+// CHECK-NEXT: Input file: {{.*}}other.h
+// CHECK-NEXT: Input file: {{.*}}module.map
+// CHECK-NEXT: Input file: {{.*}}DependsOnModule.h
+// CHECK-NEXT: Input file: {{.*}}module_private.map
+// CHECK-NEXT: Input file: {{.*}}module.map
 
 // CHECK: Diagnostic options:
 // CHECK:   IgnoreWarnings: Yes
 // CHECK:   Diagnostic flags:
 // CHECK:     -Wunused