ABI-checker: add an option to dump generated baselines into a directory. NFC

Using a directory instead of an exact file name for the generated
baseline allows the tool to use target triple as file name, which is
expected by the diagnostic phase.

Author: nkcsgexi

test/api-digester/compare-dump-abi.swift

@@ -2,12 +2,15 @@
 // RUN: %empty-directory(%t.mod2)
 // RUN: %empty-directory(%t.sdk)
 // RUN: %empty-directory(%t.module-cache)
-// RUN: %swift -emit-module -o %t.mod1/cake.swiftmodule %S/Inputs/cake_baseline/cake.swift -parse-as-library -enable-library-evolution -I %S/Inputs/APINotesLeft %clang-importer-sdk-nosource -emit-module-source-info -emit-module-source-info-path %t.mod1/cake.swiftsourceinfo
+// RUN: %empty-directory(%t.baseline)
+// RUN: %empty-directory(%t.baseline/ABI)
+
+// RUN: %swift -emit-module -o %t.mod1/cake.swiftmodule %S/Inputs/cake_baseline/cake.swift -parse-as-library -enable-library-evolution -I %S/Inputs/APINotesLeft %clang-importer-sdk-nosource -emit-module-source-info -emit-module-source-info-path %t.mod1/cake.swiftsourceinfo 2> %t.compiler-diags
 // RUN: %swift -emit-module -o %t.mod2/cake.swiftmodule %S/Inputs/cake_current/cake.swift -parse-as-library -enable-library-evolution -I %S/Inputs/APINotesRight %clang-importer-sdk-nosource -emit-module-source-info -emit-module-source-info-path %t.mod2/cake.swiftsourceinfo
-// RUN: %api-digester -dump-sdk -module cake -o %t.dump1.json -module-cache-path %t.module-cache %clang-importer-sdk-nosource -I %t.mod1 -I %S/Inputs/APINotesLeft -abi
-// RUN: %api-digester -diagnose-sdk -print-module -baseline-path %t.dump1.json -module cake -I %t.mod2 -I %S/Inputs/APINotesLeft -module-cache-path %t.module-cache %clang-importer-sdk-nosource -abi -o %t.result
-// RUN: %clang -E -P -x c %S/Outputs/Cake-abi.txt -o - | sed '/^\s*$/d' > %t.abi.expected
-// RUN: %clang -E -P -x c %t.result -o - | sed '/^\s*$/d' > %t.abi.result.tmp
+// RUN: %api-digester -dump-sdk -module cake -output-dir %t.baseline -module-cache-path %t.module-cache %clang-importer-sdk-nosource -I %t.mod1 -I %S/Inputs/APINotesLeft -abi
+// RUN: %api-digester -diagnose-sdk -print-module -baseline-dir %t.baseline -module cake -I %t.mod2 -I %S/Inputs/APINotesLeft -module-cache-path %t.module-cache %clang-importer-sdk-nosource -abi -o %t.result
+// RUN: %clang -E -P -w -x c %S/Outputs/Cake-abi.txt -o - | sed '/^\s*$/d' > %t.abi.expected
+// RUN: %clang -E -P -w -x c %t.result -o - | sed '/^\s*$/d' > %t.abi.result.tmp
 // RUN: diff -u %t.abi.expected %t.abi.result.tmp
 
 // A compiler-style diag to ensure we have source locations associated with breakages.

tools/swift-api-digester/swift-api-digester.cpp

@@ -79,6 +79,10 @@ static llvm::cl::opt<std::string>
 OutputFile("o", llvm::cl::desc("Output file"),
            llvm::cl::cat(Category));
 
+static llvm::cl::opt<std::string>
+OutputDir("output-dir", llvm::cl::desc("Directory path to where we dump the generated Json files"),
+           llvm::cl::cat(Category));
+
 static llvm::cl::opt<std::string>
 SDK("sdk", llvm::cl::desc("path to the SDK to build against"),
     llvm::cl::cat(Category));
@@ -2713,8 +2717,10 @@ static std::string getDefaultBaselinePath(const char *Main, StringRef Module,
   return BaselinePath.str();
 }
 
-static std::string getCustomBaselinePath(llvm::Triple Triple) {
+static std::string getCustomBaselinePath(llvm::Triple Triple, bool ABI) {
   llvm::SmallString<128> BaselinePath(options::BaselineDirPath);
+  // Look for ABI or API baseline
+  llvm::sys::path::append(BaselinePath, ABI? "ABI": "API");
   llvm::sys::path::append(BaselinePath, getBaselineFilename(Triple));
   return BaselinePath.str();
 }
@@ -2736,7 +2742,8 @@ static SDKNodeRoot *getBaselineFromJson(const char *Main, SDKContext &Ctx) {
          "Cannot find builtin baseline for more than one module");
   std::string Path;
   if (!options::BaselineDirPath.empty()) {
-    Path = getCustomBaselinePath(Invok.getLangOptions().Target);
+    Path = getCustomBaselinePath(Invok.getLangOptions().Target,
+                                 Ctx.checkingABI());
   } else if (options::UseEmptyBaseline) {
     Path = getEmptyBaselinePath(Main);
   } else {
@@ -2755,6 +2762,24 @@ static SDKNodeRoot *getBaselineFromJson(const char *Main, SDKContext &Ctx) {
   return Collector.getSDKRoot();
 }
 
+static std::string getJsonOutputFilePath(llvm::Triple Triple, bool ABI) {
+  if (!options::OutputFile.empty())
+    return options::OutputFile;
+  if (!options::OutputDir.empty()) {
+    llvm::SmallString<128> OutputPath(options::OutputDir);
+    llvm::sys::path::append(OutputPath, ABI? "ABI": "API");
+    if (!llvm::sys::fs::exists(OutputPath.str())) {
+      llvm::errs() << "Baseline directory " << OutputPath.str()
+                   << " doesn't exist\n";
+      exit(1);
+    }
+    llvm::sys::path::append(OutputPath, getBaselineFilename(Triple));
+    return OutputPath.str();
+  }
+  llvm::errs() << "Unable to decide output file path\n";
+  exit(1);
+}
+
 int main(int argc, char *argv[]) {
   PROGRAM_START(argc, argv);
   INITIALIZE_LLVM();
@@ -2773,7 +2798,9 @@ int main(int argc, char *argv[]) {
   switch (options::Action) {
   case ActionType::DumpSDK:
     return (prepareForDump(argv[0], InitInvok, Modules)) ? 1 :
-      dumpSDKContent(InitInvok, Modules, options::OutputFile, Opts);
+      dumpSDKContent(InitInvok, Modules,
+                     getJsonOutputFilePath(InitInvok.getLangOptions().Target, Opts.ABI),
+                     Opts);
   case ActionType::MigratorGen:
   case ActionType::DiagnoseSDKs: {
     ComparisonInputMode Mode = checkComparisonInputMode();