Fix parsing of command line options for the SPIR-V Bakend API call

Author: VyacheslavLevytskyy

llvm/lib/Target/SPIRV/SPIRVAPI.cpp

@@ -47,12 +47,22 @@ static cl::opt<char> SpirvOptLevel("spirv-O", cl::Hidden, cl::Prefix,
 static cl::opt<std::string> SpirvTargetTriple("spirv-mtriple", cl::Hidden,
                                               cl::init(""));
 
+std::once_flag InitOnceOpts;
 // Utility to accept options in a command line style.
 void parseSPIRVCommandLineOptions(const std::vector<std::string> &Options,
                                   raw_ostream *Errs) {
   static constexpr const char *Origin = "SPIRVTranslateModule";
+  // Initialize command line parser dependencies just once and in a
+  // thread-safe manner.
+  std::call_once(InitOnceOpts, []() {
+    std::vector<const char *> Argv(1, Origin);
+    cl::ParseCommandLineOptions(Argv.size(), Argv.data(), Origin,
+                                &llvm::nulls());
+  });
+  cl::ResetAllOptionOccurrences();
   if (!Options.empty()) {
     std::vector<const char *> Argv(1, Origin);
+    // Parse options.
     for (const auto &Arg : Options)
       Argv.push_back(Arg.c_str());
     cl::ParseCommandLineOptions(Argv.size(), Argv.data(), Origin, Errs);

llvm/unittests/Target/SPIRV/SPIRVAPITest.cpp

@@ -92,18 +92,29 @@ TEST_F(SPIRVAPITest, checkTranslateOk) {
 }
 
 TEST_F(SPIRVAPITest, checkTranslateError) {
-  std::string Result, Error;
-  bool Status = toSpirv(OkAssembly, Result, Error, {},
-                        {"-mtriple=spirv32-unknown-unknown"});
-  EXPECT_FALSE(Status);
-  EXPECT_TRUE(Result.empty());
-  EXPECT_THAT(Error,
-              StartsWith("SPIRVTranslateModule: Unknown command line argument "
-                         "'-mtriple=spirv32-unknown-unknown'"));
-  Status = toSpirv(OkAssembly, Result, Error, {}, {"--spirv-O 5"});
-  EXPECT_FALSE(Status);
-  EXPECT_TRUE(Result.empty());
-  EXPECT_EQ(Error, "Invalid optimization level!");
+  {
+    std::string Result, Error;
+    bool Status = toSpirv(OkAssembly, Result, Error, {},
+                          {"-mtriple=spirv32-unknown-unknown"});
+    EXPECT_FALSE(Status);
+    EXPECT_TRUE(Result.empty());
+    EXPECT_THAT(
+        Error, StartsWith("SPIRVTranslateModule: Unknown command line argument "
+                          "'-mtriple=spirv32-unknown-unknown'"));
+  }
+  {
+    std::string Result, Error;
+    bool Status = toSpirv(OkAssembly, Result, Error, {}, {"--spirv-O 5"});
+    EXPECT_FALSE(Status);
+    EXPECT_TRUE(Result.empty());
+    EXPECT_EQ(Error, "Invalid optimization level!");
+  }
+  {
+    std::string Result, Error;
+    bool Status = toSpirv(OkAssembly, Result, Error, {}, {});
+    EXPECT_TRUE(Status && Error.empty() && !Result.empty());
+    EXPECT_EQ(identify_magic(Result), file_magic::spirv_object);
+  }
 }
 
 TEST_F(SPIRVAPITest, checkTranslateSupportExtensionByOpts) {