[llvm] [SYCL] Add libsycl, a SYCL RT library implementation project (PR #144372)

[Kseniya Tikhomirova via llvm-commits]

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@@ -0,0 +1,115 @@
+#===============================================================================
+# Setup Project
+#===============================================================================
+cmake_minimum_required(VERSION 3.20.0)
+
+set(LLVM_SUBPROJECT_TITLE "libsycl")
+
+set(LIBSYCL_SOURCE_DIR  ${CMAKE_CURRENT_SOURCE_DIR})
+set(LIBSYCL_BINARY_DIR  ${CMAKE_CURRENT_BINARY_DIR})
+
+set(CMAKE_CXX_STANDARD 17)
+set(CMAKE_CXX_STANDARD_REQUIRED YES)
+set(CMAKE_CXX_EXTENSIONS OFF)
+
+#===============================================================================
+# Limitations
+#===============================================================================
+
+if (CMAKE_SYSTEM_NAME STREQUAL Windows AND NOT MSVC)
+# Build with other compilers is not configured, not guaranteed and not tested.
+    message( FATAL_ERROR
+      "On Windows libsycl supports compiler which is some version of Microsoft"
+      " Visual C++ or another compiler simulating the Visual C++ cl"
+      " command-line syntax" )
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KseniyaTikhomirova wrote:

done in https://github.com/llvm/llvm-project/pull/144372/commits/e502190b210d7fc1738a7fec623694792dd3a64c

https://github.com/llvm/llvm-project/pull/144372