[clang] [llvm] [Driver][SYCL] Add initial SYCL offload compilation support (PR #107493)

[Tom Honermann via cfe-commits]

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@@ -0,0 +1,183 @@
+//===--- 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) : D(D) {
+  InstallationCandidates.emplace_back(D.Dir + "/..");
+}
+
+void SYCLInstallationDetector::AddSYCLIncludeArgs(
+    const ArgList &DriverArgs, ArgStringList &CC1Args) const {
+  // 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");
+  // This is used to provide our wrappers around STL headers that provide
+  // additional functions/template specializations when the user includes those
+  // STL headers in their programs (e.g., <complex>).
+  SmallString<128> STLWrappersPath(IncludePath);
+  llvm::sys::path::append(STLWrappersPath, "sycl");
+  llvm::sys::path::append(STLWrappersPath, "stl_wrappers");
+  CC1Args.push_back("-internal-isystem");
+  CC1Args.push_back(DriverArgs.MakeArgString(STLWrappersPath));
+  CC1Args.push_back("-internal-isystem");
+  CC1Args.push_back(DriverArgs.MakeArgString(IncludePath));
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tahonermann wrote:

Should these additions be contingent on `--nobuiltininc` having not been specified?

https://github.com/llvm/llvm-project/pull/107493