Introduce SYCL 2020 mode

Currently, we have support for SYCL 1.2.1 (also known as SYCL 2017).
This patch introduces the start of support for SYCL 2020 mode, which is
the latest SYCL standard available at (https://www.khronos.org/registry/SYCL/specs/sycl-2020/html/sycl-2020.html).
This sets the default SYCL to be 2020 in the driver, and introduces the
notion of a "default" version (set to 2020) when cc1 is in SYCL mode
but there was no explicit -sycl-std= specified on the command line.

1 files changed, 10 insertions, 0 deletions

diff --git a/clang/lib/Frontend/CompilerInvocation.cpp b/clang/lib/Frontend/CompilerInvocation.cpp
index 9cb859f..809492a 100644
--- a/clang/lib/Frontend/CompilerInvocation.cpp
+++ b/clang/lib/Frontend/CompilerInvocation.cpp
@@ -3648,6 +3648,16 @@ bool CompilerInvocation::ParseLangArgs(LangOptions &Opts, ArgList &Args,
     }
   }
 
+  if ((Args.hasArg(OPT_fsycl_is_device) || Args.hasArg(OPT_fsycl_is_host)) &&
+      !Args.hasArg(OPT_sycl_std_EQ)) {
+    // If the user supplied -fsycl-is-device or -fsycl-is-host, but failed to
+    // provide -sycl-std=, we want to default it to whatever the default SYCL
+    // version is. I could not find a way to express this with the options
+    // tablegen because we still want this value to be SYCL_None when the user
+    // is not in device or host mode.
+    Opts.setSYCLVersion(LangOptions::SYCL_Default);
+  }
+
   if (Opts.ObjC) {
     if (Arg *arg = Args.getLastArg(OPT_fobjc_runtime_EQ)) {
       StringRef value = arg->getValue();