[CrashReproducer] Collect PCH included via -include-pch

Collect the necessary input PCH files.

Do not try to validate the AST before copying it out because if the
crash is in this path, we won't be able to collect it. Instead only
check if it's a file containg an AST.

rdar://problem/27913709

git-svn-id: https://llvm.org/svn/llvm-project/cfe/trunk@289460 91177308-0d34-0410-b5e6-96231b3b80d8

lib/Driver/Job.cpp

@@ -50,9 +50,8 @@ static bool skipArgs(const char *Flag, bool HaveCrashVFS, int &SkipNum,
   bool ShouldSkip = llvm::StringSwitch<bool>(Flag)
     .Cases("-MF", "-MT", "-MQ", "-serialize-diagnostic-file", true)
     .Cases("-o", "-coverage-file", "-dependency-file", true)
-    .Cases("-fdebug-compilation-dir", "-include-pch", true)
+    .Cases("-fdebug-compilation-dir", "-diagnostic-log-file", true)
     .Cases("-dwarf-debug-flags", "-ivfsoverlay", true)
-    .Case("-diagnostic-log-file", true)
     .Default(false);
   if (ShouldSkip)
     return true;
@@ -64,7 +63,7 @@ static bool skipArgs(const char *Flag, bool HaveCrashVFS, int &SkipNum,
     .Cases("-internal-externc-isystem", "-iprefix", true)
     .Cases("-iwithprefixbefore", "-isystem", "-iquote", true)
     .Cases("-isysroot", "-I", "-F", "-resource-dir", true)
-    .Case("-iframework", true)
+    .Cases("-iframework", "-include-pch", true)
     .Default(false);
   if (IsInclude)
     return HaveCrashVFS ? false : true;

lib/Frontend/CompilerInstance.cpp

@@ -149,6 +149,38 @@ static void collectHeaderMaps(const HeaderSearch &HS,
     MDC->addFile(Name);
 }
 
+static void collectIncludePCH(CompilerInstance &CI,
+                              std::shared_ptr<ModuleDependencyCollector> MDC) {
+  const PreprocessorOptions &PPOpts = CI.getPreprocessorOpts();
+  if (PPOpts.ImplicitPCHInclude.empty())
+    return;
+
+  StringRef PCHInclude = PPOpts.ImplicitPCHInclude;
+  FileManager &FileMgr = CI.getFileManager();
+  const DirectoryEntry *PCHDir = FileMgr.getDirectory(PCHInclude);
+  if (!PCHDir) {
+    MDC->addFile(PCHInclude);
+    return;
+  }
+
+  std::error_code EC;
+  SmallString<128> DirNative;
+  llvm::sys::path::native(PCHDir->getName(), DirNative);
+  vfs::FileSystem &FS = *FileMgr.getVirtualFileSystem();
+  SimpleASTReaderListener Validator(CI.getPreprocessor());
+  for (vfs::directory_iterator Dir = FS.dir_begin(DirNative, EC), DirEnd;
+       Dir != DirEnd && !EC; Dir.increment(EC)) {
+    // Check whether this is an AST file. ASTReader::isAcceptableASTFile is not
+    // used here since we're not interested in validating the PCH at this time,
+    // but only to check whether this is a file containing an AST.
+    if (!ASTReader::readASTFileControlBlock(
+            Dir->getName(), FileMgr, CI.getPCHContainerReader(),
+            /*FindModuleFileExtensions=*/false, Validator,
+            /*ValidateDiagnosticOptions=*/false))
+      MDC->addFile(Dir->getName());
+  }
+}
+
 // Diagnostics
 static void SetUpDiagnosticLog(DiagnosticOptions *DiagOpts,
                                const CodeGenOptions *CodeGenOpts,
@@ -379,6 +411,7 @@ void CompilerInstance::createPreprocessor(TranslationUnitKind TUKind) {
   if (ModuleDepCollector) {
     addDependencyCollector(ModuleDepCollector);
     collectHeaderMaps(PP->getHeaderSearchInfo(), ModuleDepCollector);
+    collectIncludePCH(*this, ModuleDepCollector);
   }
 
   for (auto &Listener : DependencyCollectors)

test/Modules/crash-vfs-include-pch.m

@@ -0,0 +1,43 @@
+// REQUIRES: crash-recovery, shell, system-darwin
+//
+// RUN: rm -rf %t
+// RUN: mkdir -p %t/m %t/out
+
+// RUN: %clang_cc1 -x objective-c-header -emit-pch %S/Inputs/pch-used.h \
+// RUN:     -o %t/out/pch-used.h.pch -fmodules -fimplicit-module-maps \
+// RUN:     -fmodules-cache-path=%t/cache -O0 \
+// RUN:     -isystem %S/Inputs/System/usr/include
+
+// RUN: not env FORCE_CLANG_DIAGNOSTICS_CRASH= TMPDIR=%t TEMP=%t TMP=%t \
+// RUN: %clang %s -E -include-pch %t/out/pch-used.h.pch -fmodules -nostdlibinc \
+// RUN:     -fimplicit-module-maps -fmodules-cache-path=%t/cache -O0 \
+// RUN:     -Xclang -fno-validate-pch -isystem %S/Inputs/System/usr/include \
+// RUN:     -o %t/output.E 2>&1 | FileCheck %s
+
+// RUN: FileCheck --check-prefix=CHECKSH %s -input-file %t/crash-vfs-*.sh
+// RUN: FileCheck --check-prefix=CHECKYAML %s -input-file \
+// RUN:   %t/crash-vfs-*.cache/vfs/vfs.yaml
+
+void f() { SPXTrace(); }
+void g() { double x = DBL_MAX; }
+
+// CHECK: Preprocessed source(s) and associated run script(s) are located at:
+// CHECK-NEXT: note: diagnostic msg: {{.*}}.m
+// CHECK-NEXT: note: diagnostic msg: {{.*}}.cache
+
+// CHECKSH: "-include-pch" "/[[INCPATH:.*]]/out/pch-used.h.pch"
+// CHECKSH: "crash-vfs-{{[^ ]*}}.m"
+// CHECKSH: "-ivfsoverlay" "crash-vfs-{{[^ ]*}}.cache/vfs/vfs.yaml"
+// CHECKSH: "-fmodules-cache-path=crash-vfs-{{[^ ]*}}.cache/repro-modules"
+
+// CHECKYAML: 'case-sensitive':
+// CHECKYAML-NEXT: 'use-external-names': 'false',
+// CHECKYAML-NEXT: 'overlay-relative': 'true',
+// CHECKYAML-NEXT: 'ignore-non-existent-contents': 'false'
+// CHECKYAML: 'type': 'directory'
+// CHECKYAML: 'name': "/[[PATH:.*]]/out",
+// CHECKYAML-NEXT: 'contents': [
+// CHECKYAML-NEXT:   {
+// CHECKYAML-NEXT:     'type': 'file',
+// CHECKYAML-NEXT:     'name': "pch-used.h.pch",
+// CHECKYAML-NEXT:     'external-contents': "/[[PATH]]/out/pch-used.h.pch"