Diab: Add tests covering the Diab toolchains

Run the tests only if enabled explicitly by an undocumented cache
entry.  We will enable it on hosts known to have the toolchains.

Closes: #26735

Tests/RunCMake/CMakeLists.txt

@@ -1369,3 +1369,7 @@ if(CMake_TEST_TICLANG_TOOLCHAINS)
   add_RunCMake_test(TIClang "-DCMake_TEST_TICLANG_TOOLCHAINS=${TOOLCHAINS}")
   set_property(TEST RunCMake.TIClang APPEND PROPERTY LABELS "TIClang")
 endif()
+if(CMake_TEST_Diab_TOOLCHAINS)
+  add_RunCMake_test(Diab -DCMake_TEST_Diab_TOOLCHAINS=${CMake_TEST_Diab_TOOLCHAINS})
+  set_property(TEST RunCMake.Diab APPEND PROPERTY LABELS "Diab")
+endif()

Tests/RunCMake/Diab/CMakeLists.txt

@@ -0,0 +1,3 @@
+cmake_minimum_required(VERSION 4.0)
+project(${RunCMake_TEST} NONE)
+include(${RunCMake_TEST}.cmake)

Tests/RunCMake/Diab/RunCMakeTest.cmake

@@ -0,0 +1,42 @@
+include(RunCMake)
+
+# Locate Diab toolchain
+if(RunCMake_GENERATOR MATCHES "Makefile|Ninja")
+  file(GLOB _diab_toolchains
+    "${CMake_TEST_Diab_TOOLCHAINS}/*/*/bin/dcc*" )
+  if(_diab_toolchains STREQUAL "")
+    message(FATAL_ERROR "Could not find any Diab toolchains at: ${CMake_TEST_Diab_TOOLCHAINS}.")
+  endif()
+endif()
+
+function(run_toolchain case)
+  set(RunCMake_TEST_BINARY_DIR ${RunCMake_BINARY_DIR}/${case}-build)
+  run_cmake_with_options(${case} ${ARGN})
+  set(RunCMake_TEST_NO_CLEAN 1)
+  run_cmake_command(${case}-build ${CMAKE_COMMAND} --build .)
+endfunction()
+
+
+foreach(_diab_toolchain IN LISTS _diab_toolchains)
+  message(STATUS "Found Diab toolchain: ${_diab_toolchain}")
+  cmake_path(GET _diab_toolchain PARENT_PATH BIN_DIR)
+  set(c_comp ${BIN_DIR}/dcc)
+  set(cxx_comp ${BIN_DIR}/dplus)
+
+  # Create an executable from .c sources only.
+  run_toolchain(diab-c
+    -DCMAKE_C_COMPILER=${c_comp}
+  )
+
+  # Create an executale from .c and .cxx sources.
+  run_toolchain(diab-cxx
+    -DCMAKE_C_COMPILER=${c_comp}
+    -DCMAKE_CXX_COMPILER=${cxx_comp}
+  )
+
+  # Create an executable from mixed, c, cxx and assembly.
+  run_toolchain(diab-asm
+    -DCMAKE_C_COMPILER=${c_comp}
+    -DCMAKE_CXX_COMPILER=${cxx_comp}
+  )
+endforeach()

Tests/RunCMake/Diab/diab-asm.cmake

@@ -0,0 +1,2 @@
+enable_language(ASM)
+add_executable(exec-asm module.s)

Tests/RunCMake/Diab/diab-c.cmake

@@ -0,0 +1,2 @@
+enable_language(C)
+add_executable(exec-c module.c)

Tests/RunCMake/Diab/diab-cxx.cmake

@@ -0,0 +1,2 @@
+enable_language(CXX)
+add_executable(exec-cxx module.cxx)

Tests/RunCMake/Diab/diab-lib.cmake

@@ -0,0 +1,7 @@
+enable_language(C)
+add_library(diab-test-lib libmod.c)
+
+add_executable(exec-lib-c module.c)
+target_compile_options(exec-lib-c)
+target_compile_definitions(exec-lib-c PRIVATE __USE_LIBFUN)
+target_link_libraries(exec-lib-c PRIVATE diab-test-lib)

Tests/RunCMake/Diab/libmod.c

@@ -0,0 +1,4 @@
+int diab_libfun()
+{
+  return 42;
+}

Tests/RunCMake/Diab/module.c

@@ -0,0 +1,15 @@
+#include "module.h"
+#if defined(__USE_LIBFUN)
+extern int diab_libfun();
+#endif
+
+int i;
+int main()
+{
+#if defined(__USE_LIBFUN)
+  i = diab_libfun();
+#else
+  i = INTERNAL;
+#endif
+  return i;
+}

Tests/RunCMake/Diab/module.cxx

@@ -0,0 +1,7 @@
+#include "module.h"
+int i;
+int main()
+{
+  i = INTERNAL;
+  return i;
+}

Tests/RunCMake/Diab/module.h

@@ -0,0 +1,12 @@
+#ifndef __MODULE_H__
+#define __MODULE_H__
+
+#if defined(__cplusplus)
+#  define INTERNAL 64
+#elif !defined(__cplusplus)
+#  define INTERNAL 32
+#else
+#  error "Unable to determine INTERNAL symbol."
+#endif
+
+#endif /* __MODULE_H__ */

Tests/RunCMake/Diab/module.s

@@ -0,0 +1,10 @@
+; module.s: assembly "main" function returns 32.
+;
+        .name           "module.s"
+        .text
+        .align          2
+
+        .globl          main
+main:
+        diab.li         r3,32
+        blr