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

[Tom Honermann 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");
----------------
tahonermann wrote:

I think we should work this out with the SYCL library folks before making this change then since duplicate paths in the header search path can be problematic and, when they are, difficult to work around.

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