[SYCL][Driver] Add off value for device code split option

This will help disable device code split if some previous option enabled
it.

Signed-off-by: Mariya Podchishchaeva <[email protected]>

Author: Fznamznon

clang/include/clang/Driver/Options.td

@@ -1821,8 +1821,8 @@ def fsycl_link_targets_EQ : CommaJoined<["-"], "fsycl-link-targets=">, Flags<[Dr
   HelpText<"Specify comma-separated list of triples SYCL offloading targets to produce linked device images">;
 def fsycl_device_code_split_EQ : Joined<["-"], "fsycl-device-code-split=">,
    Flags<[CC1Option, CoreOption]>, HelpText<"Perform SYCL device code split: per_kernel (device code module is "
-  "created for each SYCL kernel) | per_source (device code module is created for each source (translation unit)). "
-  "Default is no device code split - all kernels go into a single module`">, Values<"per_source,per_kernel">;
+  "created for each SYCL kernel) | per_source (device code module is created for each source (translation unit)) | off (no device code split). "
+  "Default is 'off' - all kernels go into a single module`">, Values<"per_source, per_kernel, off">;
 def fsycl_device_code_split : Flag<["-"], "fsycl-device-code-split">, Alias<fsycl_device_code_split_EQ>,
   AliasArgs<["per_source"]>, Flags<[CC1Option, CoreOption]>,
   HelpText<"Perform SYCL device code split in the per_source mode i.e. create a device code module for each source (translation unit)">;

clang/lib/Driver/Driver.cpp

@@ -3575,7 +3575,10 @@ class OffloadingActionBuilder final {
       Arg *SYCLLinkTargets = Args.getLastArg(
                                   options::OPT_fsycl_link_targets_EQ);
       WrapDeviceOnlyBinary = Args.hasArg(options::OPT_fsycl_link_EQ);
-      DeviceCodeSplit = Args.hasArg(options::OPT_fsycl_device_code_split);
+      auto *DeviceCodeSplitArg =
+          Args.getLastArg(options::OPT_fsycl_device_code_split_EQ);
+      DeviceCodeSplit = DeviceCodeSplitArg &&
+                        DeviceCodeSplitArg->getValue() != StringRef("off");
       // Device only compilation for -fsycl-link (no FPGA) and
       // -fsycl-link-targets
       CompileDeviceOnly =