IntelLLVM: Add support for Intel LLVM-based compilers

Using a single ID 'IntelLLVM' for the suite of Intel compilers based on
the LLVM backend.  The 'IntelLLVM' ID are used for C, C++, and Fortran.
Data Parallel C++ will be handled in a separate commit.

The C and C++ definitions are based on the Clang definitions.  The Intel
LLVM-based C and C++ compilers are based on the Clang front end, so
existing Clang options are more likely to be a good match than options
for the older Intel compilers.

Fortran is based on the older Fortran front end with the LLVM backend.
It has a similar interface to the older versions, though many options
are shared with the C and C++ compilers.

Fixes: #21561
Signed-off-by: William R. Dieter <william.r.dieter@intel.com>

1 files changed, 55 insertions, 0 deletions

diff --git a/Modules/Platform/Linux-IntelLLVM.cmake b/Modules/Platform/Linux-IntelLLVM.cmake
new file mode 100644
index 0000000..1363b44
--- /dev/null
+++ b/Modules/Platform/Linux-IntelLLVM.cmake
@@ -0,0 +1,55 @@
+# Distributed under the OSI-approved BSD 3-Clause License.  See accompanying
+# file Copyright.txt or https://cmake.org/licensing for details.
+
+
+# This module is shared by multiple languages; use include blocker.
+if(__LINUX_COMPILER_INTEL_LLVM)
+  return()
+endif()
+set(__LINUX_COMPILER_INTEL_LLVM 1)
+
+if(NOT XIAR)
+  set(_intel_xiar_hints)
+  foreach(lang C CXX Fortran)
+    if(IS_ABSOLUTE "${CMAKE_${lang}_COMPILER}")
+      get_filename_component(_hint "${CMAKE_${lang}_COMPILER}" PATH)
+      list(APPEND _intel_xiar_hints ${_hint})
+    endif()
+  endforeach()
+  find_program(XIAR NAMES xiar HINTS ${_intel_xiar_hints})
+  mark_as_advanced(XIAR)
+endif()
+
+macro(__linux_compiler_intel_llvm lang)
+  set(CMAKE_${lang}_COMPILE_OPTIONS_PIC "-fPIC")
+  set(CMAKE_${lang}_COMPILE_OPTIONS_PIE "-fPIE")
+  set(_CMAKE_${lang}_PIE_MAY_BE_SUPPORTED_BY_LINKER NO)
+  set(_CMAKE_${lang}_PIE_MAY_BE_SUPPORTED_BY_LINKER YES)
+  set(CMAKE_${lang}_LINK_OPTIONS_PIE ${CMAKE_${lang}_COMPILE_OPTIONS_PIE} "-pie")
+  set(CMAKE_${lang}_LINK_OPTIONS_NO_PIE "-no-pie")
+  set(CMAKE_SHARED_LIBRARY_${lang}_FLAGS "-fPIC")
+  set(CMAKE_SHARED_LIBRARY_CREATE_${lang}_FLAGS "-shared")
+
+  # We pass this for historical reasons.  Projects may have
+  # executables that use dlopen but do not set ENABLE_EXPORTS.
+  set(CMAKE_SHARED_LIBRARY_LINK_${lang}_FLAGS "-rdynamic")
+
+  set(CMAKE_${lang}_LINKER_WRAPPER_FLAG "-Wl,")
+  set(CMAKE_${lang}_LINKER_WRAPPER_FLAG_SEP ",")
+
+  set(_CMAKE_${lang}_IPO_SUPPORTED_BY_CMAKE YES)
+
+  if(XIAR)
+    # INTERPROCEDURAL_OPTIMIZATION
+    set(CMAKE_${lang}_COMPILE_OPTIONS_IPO -ipo)
+    set(CMAKE_${lang}_CREATE_STATIC_LIBRARY_IPO
+      "${XIAR} cr <TARGET> <LINK_FLAGS> <OBJECTS> "
+      "${XIAR} -s <TARGET> ")
+    set(_CMAKE_${lang}_IPO_MAY_BE_SUPPORTED_BY_COMPILER YES)
+    set(_CMAKE_${lang}_IPO_LEGACY_BEHAVIOR YES)
+  else()
+    set(_CMAKE_${lang}_IPO_MAY_BE_SUPPORTED_BY_COMPILER NO)
+  endif()
+
+  set(CMAKE_${lang}_COMPILE_OPTIONS_VISIBILITY "-fvisibility=")
+endmacro()