[clang] [llvm] Reland - [Driver][SYCL] Add initial SYCL offload compilation support … (PR #117268)

[Michael Toguchi via llvm-commits]

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@@ -0,0 +1,179 @@
+//===--- SYCL.cpp - SYCL Tool and ToolChain Implementations -----*- 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
+//
+//===----------------------------------------------------------------------===//
+#include "SYCL.h"
+#include "CommonArgs.h"
+#include "llvm/Support/Path.h"
+
+using namespace clang::driver;
+using namespace clang::driver::toolchains;
+using namespace clang::driver::tools;
+using namespace clang;
+using namespace llvm::opt;
+
+SYCLInstallationDetector::SYCLInstallationDetector(
+    const Driver &D, const llvm::Triple &HostTriple,
+    const llvm::opt::ArgList &Args)
+    : D(D) {}
+
+void SYCLInstallationDetector::AddSYCLIncludeArgs(
+    const ArgList &DriverArgs, ArgStringList &CC1Args) const {
+  if (DriverArgs.hasArg(clang::driver::options::OPT_nobuiltininc))
+    return;
+
+  // Add the SYCL header search locations in the specified order.
+  //   ../include/sycl/stl_wrappers
+  //   ../include
+  SmallString<128> IncludePath(D.Dir);
+  llvm::sys::path::append(IncludePath, "..");
+  llvm::sys::path::append(IncludePath, "include");
----------------
mdtoguchi wrote:

I would guess this depends on how ultimately the `include/sycl` headers are installed and how we should point to them.  As the headers are not currently part of the build, this is basically just  a location in which to try and find the SYCL specific headers (this is what we are doing in intel/llvm).

https://github.com/llvm/llvm-project/pull/117268