[flang] Skip `Fortran STOP:` before message when NO_STOP_MESSAGE is set

[jeanPerier]

Summary

In 'STOP bye bye', do not print 'Fortran STOP:` before 'bye bye' when
NO_STOP_MESSAGE environment variable is set at runtime.

Also only exit with code 1 in StopStatementText if this is an ERROR STOP.
This matches other compiler behaviors.

Move STOP related unit tests in their own test file and add new tests to
cover this change.

flang/runtime/stop.cpp

[[noreturn]] void RTNAME(StopStatement)(
   }
   std::exit(code);
 }
 
 [[noreturn]] void RTNAME(StopStatementText)(
     const char *code, std::size_t length, bool isErrorStop, bool quiet) {
   CloseAllExternalUnits("STOP statement");
   if (!quiet) {
+    if (Fortran::runtime::executionEnvironment.noStopMessage && !isErrorStop) {
+      std::fprintf(stderr, "%.*s\n", static_cast<int>(length), code);
+    } else {
       std::fprintf(stderr, "Fortran %s: %.*s\n",
           isErrorStop ? "ERROR STOP" : "STOP", static_cast<int>(length), code);
+    }
     DescribeIEEESignaledExceptions();
   }
+  if (isErrorStop) {
     std::exit(EXIT_FAILURE);
+  } else {
+    std::exit(EXIT_SUCCESS);
+  }
 }
 
 static bool StartPause() {
   if (Fortran::runtime::io::IsATerminal(0)) {
     Fortran::runtime::io::IoErrorHandler handler{"PAUSE statement"};
     Fortran::runtime::io::ExternalFileUnit::FlushAll(handler);
     return true;
   }

flang/unittests/Runtime/CMakeLists.txt

 add_flang_unittest(FlangRuntimeTests
   BufferTest.cpp
   CharacterTest.cpp
   CommandTest.cpp
   CrashHandlerFixture.cpp
   ExternalIOTest.cpp
   Format.cpp
   ListInputTest.cpp
   Matmul.cpp
   MiscIntrinsic.cpp
   Namelist.cpp
   Numeric.cpp
   NumericalFormatTest.cpp
   Random.cpp
   Reduction.cpp
   RuntimeCrashTest.cpp
+  Stop.cpp
   Time.cpp
   Transformational.cpp
 )
 
 target_link_libraries(FlangRuntimeTests
   PRIVATE
   FortranRuntime
 )

flang/unittests/Runtime/RuntimeCrashTest.cpp

 //===-- flang/unittests/RuntimeGTest/CrashHandlerFixture.cpp ----*- C++ -*-===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
 /// Selected APIs are tested here to support development of unit tests for other
 /// runtime components and ensure the test fixture handles crashes as we expect.
 //
 //===----------------------------------------------------------------------===//
 #include "CrashHandlerFixture.h"
 #include "../../runtime/terminator.h"
 #include "flang/Runtime/io-api.h"
-#include "flang/Runtime/stop.h"
 #include <gtest/gtest.h>
 
 using namespace Fortran::runtime;
 using namespace Fortran::runtime::io;
 
 //------------------------------------------------------------------------------
 /// Test crashes through direct calls to terminator methods
 //------------------------------------------------------------------------------
TEST(TestIOCrash, OverwriteBufferIntegerTest) {
   static char buffer[bufferSize];
   static const char *format{"(I1)"};
   auto *cookie{IONAME(BeginInternalFormattedOutput)(
       buffer, bufferSize, format, std::strlen(format))};
   IONAME(OutputInteger64)(cookie, 0xdeadbeef);
   ASSERT_DEATH(IONAME(OutputInteger64)(cookie, 0xdeadbeef),
       "Internal write overran available records");
 }
-
-TEST(TestIOCrash, StopTest) {
-  EXPECT_EXIT(RTNAME(StopStatement)(), testing::ExitedWithCode(EXIT_SUCCESS),
-      "Fortran STOP");
-}
-
-TEST(TestIOCrash, FailImageTest) {
-  EXPECT_EXIT(
-      RTNAME(FailImageStatement)(), testing::ExitedWithCode(EXIT_FAILURE), "");
-}
-
-TEST(TestIOCrash, ExitTest) {
-  EXPECT_EXIT(RTNAME(Exit)(), testing::ExitedWithCode(EXIT_SUCCESS), "");
-  EXPECT_EXIT(
-      RTNAME(Exit)(EXIT_FAILURE), testing::ExitedWithCode(EXIT_FAILURE), "");
-}
-
-TEST(TestIOCrash, AbortTest) { EXPECT_DEATH(RTNAME(Abort)(), ""); }

flang/unittests/Runtime/Stop.cpp

+//===-- flang/unittests/Runtime/Stop.cpp ----------------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+/// Test runtime API for STOP statement and runtime API to kill the program.
+//
+//===----------------------------------------------------------------------===//
+#include "flang/Runtime/stop.h"
+#include "CrashHandlerFixture.h"
+#include "../../runtime/environment.h"
+#include <cstdlib>
+#include <gtest/gtest.h>
+
+using namespace Fortran::runtime;
+
+struct TestProgramEnd : CrashHandlerFixture {};
+
+TEST(TestProgramEnd, StopTest) {
+  EXPECT_EXIT(RTNAME(StopStatement)(), testing::ExitedWithCode(EXIT_SUCCESS),
+      "Fortran STOP");
+}
+
+TEST(TestProgramEnd, StopTestNoStopMessage) {
+  putenv(const_cast<char *>("NO_STOP_MESSAGE=1"));
+  Fortran::runtime::executionEnvironment.Configure(0, nullptr, nullptr);
+  EXPECT_EXIT(
+      RTNAME(StopStatement)(), testing::ExitedWithCode(EXIT_SUCCESS), "");
+}
+
+TEST(TestProgramEnd, StopMessageTest) {
+  static const char *message{"bye bye"};
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/false, /*quiet=*/false),
+      testing::ExitedWithCode(EXIT_SUCCESS), "Fortran STOP: bye bye");
+
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/false, /*quiet=*/true),
+      testing::ExitedWithCode(EXIT_SUCCESS), "");
+
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/true, /*quiet=*/false),
+      testing::ExitedWithCode(EXIT_FAILURE), "Fortran ERROR STOP: bye bye");
+
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/true, /*quiet=*/true),
+      testing::ExitedWithCode(EXIT_FAILURE), "");
+}
+
+TEST(TestProgramEnd, NoStopMessageTest) {
+  putenv(const_cast<char *>("NO_STOP_MESSAGE=1"));
+  Fortran::runtime::executionEnvironment.Configure(0, nullptr, nullptr);
+  static const char *message{"bye bye"};
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/false, /*quiet=*/false),
+      testing::ExitedWithCode(EXIT_SUCCESS), "bye bye");
+
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/false, /*quiet=*/true),
+      testing::ExitedWithCode(EXIT_SUCCESS), "");
+
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/true, /*quiet=*/false),
+      testing::ExitedWithCode(EXIT_FAILURE), "Fortran ERROR STOP: bye bye");
+
+  EXPECT_EXIT(RTNAME(StopStatementText)(message, std::strlen(message),
+                  /*isErrorStop=*/true, /*quiet=*/true),
+      testing::ExitedWithCode(EXIT_FAILURE), "");
+}
+
+TEST(TestProgramEnd, FailImageTest) {
+  EXPECT_EXIT(
+      RTNAME(FailImageStatement)(), testing::ExitedWithCode(EXIT_FAILURE), "");
+}
+
+TEST(TestProgramEnd, ExitTest) {
+  EXPECT_EXIT(RTNAME(Exit)(), testing::ExitedWithCode(EXIT_SUCCESS), "");
+  EXPECT_EXIT(
+      RTNAME(Exit)(EXIT_FAILURE), testing::ExitedWithCode(EXIT_FAILURE), "");
+}
+
+TEST(TestProgramEnd, AbortTest) { EXPECT_DEATH(RTNAME(Abort)(), ""); }