[DependencyScanning] Canonicalize `CodeGenOptions.RelaxAll`

[akyrtzi]

Summary

This is particularly useful to avoid diverging the modules between a PCH and a translation-unit compilation.

[jansvoboda11]

clang/tools/clang-scan-deps/ClangScanDeps.cpp

958

This assumes FD is not empty, i.e. the -format experimental-full argument. We should probably error out early if that's not the case.

WDYT about changing the new -brief flag into something like -format experimental-brief? We could avoid the dependency between arguments and we'd also make it clear the make and p1689 don't have a brief variant.

[akyrtzi]

clang/tools/clang-scan-deps/ClangScanDeps.cpp

958

This assumes FD is not empty,

Ah, good catch! I'll fix.

WDYT about changing the new -brief flag into something like -format experimental-brief?

I consider -brief orthogonal to the format kind, there's no reason we can't have brief versions of the other formats.

[akyrtzi]

Make sure to check FD is valid.

[akyrtzi]

Remove -optimize-args from the test invocations since it's not relevant for the test.

[jansvoboda11]

clang/tools/clang-scan-deps/ClangScanDeps.cpp

958

I consider -brief orthogonal to the format kind, there's no reason we can't have brief versions of the other formats.

How would a brief make or P1689 output look like?

[akyrtzi]

clang/tools/clang-scan-deps/ClangScanDeps.cpp

958

make could print the number of file dependencies and P1689 maybe also prints the number of modules (I'm not familiar with that).

In the apple fork there are additional formats added that would have the same -brief output as in this patch, without any changes.

[jansvoboda11]

LGTM. Note that I think we should consider renaming the -format flag in the future. Ideally, it should reflect the fact that the scanner is doing different work, not just formatting the output differently.

[akyrtzi]

Rebase on top of main.

clang/lib/Tooling/DependencyScanning/ModuleDepCollector.cpp

ModuleDepCollector::makeInvocationForModuleBuildWithoutOutputs(
   // TODO: Figure out better way to set options to their default value.
   CI.getCodeGenOpts().MainFileName.clear();
   CI.getCodeGenOpts().DwarfDebugFlags.clear();
   if (!CI.getLangOpts()->ModulesCodegen) {
     CI.getCodeGenOpts().DebugCompilationDir.clear();
     CI.getCodeGenOpts().CoverageCompilationDir.clear();
     CI.getCodeGenOpts().CoverageDataFile.clear();
     CI.getCodeGenOpts().CoverageNotesFile.clear();
+    CI.getCodeGenOpts().RelaxAll = false;
   }
 
   // Map output paths that affect behaviour to "-" so their existence is in the
   // context hash. The final path will be computed in addOutputPaths.
   if (!CI.getDiagnosticOpts().DiagnosticSerializationFile.empty())
     CI.getDiagnosticOpts().DiagnosticSerializationFile = "-";
   if (!CI.getDependencyOutputOpts().OutputFile.empty())
     CI.getDependencyOutputOpts().OutputFile = "-";

clang/test/ClangScanDeps/shared-module-for-tu-and-pch.c

+// RUN: rm -rf %t
+// RUN: split-file %s %t
+
+// RUN: sed "s|DIR|%/t|g" %t/cdb.json.debug.template > %t/cdb.debug.json
+// RUN: sed "s|DIR|%/t|g" %t/cdb.json.release.template > %t/cdb.release.json
+
+// RUN: clang-scan-deps -compilation-database %t/cdb.debug.json -format=experimental-full -brief | FileCheck %s
+// RUN: clang-scan-deps -compilation-database %t/cdb.release.json -format=experimental-full -brief | FileCheck %s
+// CHECK: num modules: 1
+
+//--- cdb.json.debug.template
+[{
+  "directory": "DIR",
+  "file": "DIR/tu.c",
+  "command": "clang -target x86_64-apple-macosx12 -x c -fmodules -gmodules -fmodules-cache-path=DIR/cache -I DIR/include -c DIR/tu.c -o DIR/tu.o -O0 -g"
+},
+{
+  "directory": "DIR",
+  "file": "DIR/tu.prefix.h",
+  "command": "clang -target x86_64-apple-macosx12 -x c-header -fmodules -gmodules -fmodules-cache-path=DIR/cache -I DIR/include -c DIR/tu.prefix.h -o DIR/tu.pch -O0 -g"
+}]
+//--- cdb.json.release.template
+[{
+  "directory": "DIR",
+  "file": "DIR/tu.c",
+  "command": "clang -target x86_64-apple-macosx12 -x c -fmodules -gmodules -fmodules-cache-path=DIR/cache -I DIR/include -c DIR/tu.c -o DIR/tu.o -Os -g"
+},
+{
+  "directory": "DIR",
+  "file": "DIR/tu.prefix.h",
+  "command": "clang -target x86_64-apple-macosx12 -x c-header -fmodules -gmodules -fmodules-cache-path=DIR/cache -I DIR/include -c DIR/tu.prefix.h -o DIR/tu.pch -Os -g"
+}]
+
+//--- include/module.modulemap
+module Top { header "top.h" }
+//--- include/top.h
+#define TOP int
+//--- tu.c
+#include "top.h"
+TOP fn(void);
+//--- tu.prefix.h
+#include "top.h"

clang/tools/clang-scan-deps/ClangScanDeps.cpp

 static bool EagerLoadModules;
 static unsigned NumThreads = 0;
 static std::string CompilationDB;
 static std::string ModuleName;
 static std::vector<std::string> ModuleDepTargets;
 static bool DeprecatedDriverCommand;
 static ResourceDirRecipeKind ResourceDirRecipe;
 static bool Verbose;
+static bool BriefResult;
 static std::vector<const char *> CommandLine;
 
 #ifndef NDEBUG
 static constexpr bool DoRoundTripDefault = true;
 #else
 static constexpr bool DoRoundTripDefault = false;
 #endif
 
if (!Kind) {
                       "option named '"
                    << A->getValue() << "'\n";
       std::exit(1);
     }
     ResourceDirRecipe = *Kind;
   }
 
   Verbose = Args.hasArg(OPT_verbose);
+  BriefResult = Args.hasArg(OPT_brief_result);
 
   RoundTripArgs = Args.hasArg(OPT_round_trip_args);
 
   if (auto *A = Args.getLastArgNoClaim(OPT_DASH_DASH))
     CommandLine.insert(CommandLine.end(), A->getValues().begin(),
                        A->getValues().end());
 }
 
void printFullOutput(raw_ostream &OS) {
     Object Output{
         {"modules", std::move(OutModules)},
         {"translation-units", std::move(TUs)},
     };
 
     OS << llvm::formatv("{0:2}\n", Value(std::move(Output)));
   }
 
+  size_t getNumModules() const { return Modules.size(); }
+
 private:
   struct IndexedModuleID {
     ModuleID ID;
     mutable size_t InputIndex;
 
     bool operator==(const IndexedModuleID &Other) const {
       return ID.ModuleName == Other.ID.ModuleName &&
              ID.ContextHash == Other.ID.ContextHash;
for (unsigned I = 0; I < Pool.getThreadCount(); ++I) {
     });
   }
   Pool.wait();
 
   if (RoundTripArgs)
     if (FD && FD->roundTripCommands(llvm::errs()))
       HadErrors = true;
 
+  if (BriefResult && FD) {
+    llvm::outs() << "num modules: " << FD->getNumModules() << '\n';
+    return HadErrors;
+  }
+
   if (Format == ScanningOutputFormat::Full)
     FD->printFullOutput(llvm::outs());
   else if (Format == ScanningOutputFormat::P1689)
     PD.printDependencies(llvm::outs());
 
   return HadErrors;
 }

clang/tools/clang-scan-deps/Opts.td

 defm dependency_target : Eq<"dependency-target", "The names of dependency targets for the dependency file">;
 
 def deprecated_driver_command : F<"deprecated-driver-command", "use a single driver command to build the tu (deprecated)">;
 
 defm resource_dir_recipe : Eq<"resource-dir-recipe", "How to produce missing '-resource-dir' argument">;
 
 def verbose : F<"v", "Use verbose output">;
 
+def brief_result : F<"brief", "Use brief dependency info output">;
+
 def round_trip_args : F<"round-trip-args", "verify that command-line arguments are canonical by parsing and re-serializing">;
 
 def DASH_DASH : Option<["--"], "", KIND_REMAINING_ARGS>;
 No newline at end of file