[OpenCL] C++ for OpenCL version 2021 introduced to command line.

Introduces language standard `lang_openclcpp2021` and allows
`clc++2021` as a version flag for `-cl-std` in command line.
Defines macros related to C++ for OpenCL version 2021.

C++ for OpenCL version 2021 has been proposed in an RFC:
https://lists.llvm.org/pipermail/cfe-dev/2021-August/068593.html

Differential Revision: https://reviews.llvm.org/D108038

clang/include/clang/Basic/LangStandards.def

@@ -180,12 +180,18 @@ LANGSTANDARD(opencl20, "cl2.0",
 LANGSTANDARD(opencl30, "cl3.0",
              OpenCL, "OpenCL 3.0",
              LineComment | C99 | Digraphs | HexFloat | OpenCL)
+
 LANGSTANDARD(openclcpp10, "clc++1.0",
              OpenCL, "C++ for OpenCL 1.0",
              LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | CPlusPlus17 |
              Digraphs | HexFloat | OpenCL)
 LANGSTANDARD_ALIAS(openclcpp10, "clc++")
 
+LANGSTANDARD(openclcpp2021, "clc++2021",
+             OpenCL, "C++ for OpenCL 2021",
+             LineComment | CPlusPlus | CPlusPlus11 | CPlusPlus14 | CPlusPlus17 |
+             Digraphs | HexFloat | OpenCL)
+
 LANGSTANDARD_ALIAS_DEPR(opencl10, "CL")
 LANGSTANDARD_ALIAS_DEPR(opencl11, "CL1.1")
 LANGSTANDARD_ALIAS_DEPR(opencl12, "CL1.2")
@@ -193,6 +199,7 @@ LANGSTANDARD_ALIAS_DEPR(opencl20, "CL2.0")
 LANGSTANDARD_ALIAS_DEPR(opencl30, "CL3.0")
 LANGSTANDARD_ALIAS_DEPR(openclcpp10, "CLC++")
 LANGSTANDARD_ALIAS_DEPR(openclcpp10, "CLC++1.0")
+LANGSTANDARD_ALIAS_DEPR(openclcpp2021, "CLC++2021")
 
 // CUDA
 LANGSTANDARD(cuda, "cuda", CUDA, "NVIDIA CUDA(tm)",

clang/include/clang/Driver/Options.td

@@ -866,7 +866,7 @@ def cl_no_signed_zeros : Flag<["-"], "cl-no-signed-zeros">, Group<opencl_Group>,
   MarshallingInfoFlag<LangOpts<"CLNoSignedZero">>;
 def cl_std_EQ : Joined<["-"], "cl-std=">, Group<opencl_Group>, Flags<[CC1Option]>,
   HelpText<"OpenCL language standard to compile for.">,
-  Values<"cl,CL,cl1.0,CL1.0,cl1.1,CL1.1,cl1.2,CL1.2,cl2.0,CL2.0,cl3.0,CL3.0,clc++,CLC++,clc++1.0,CLC++1.0">;
+  Values<"cl,CL,cl1.0,CL1.0,cl1.1,CL1.1,cl1.2,CL1.2,cl2.0,CL2.0,cl3.0,CL3.0,clc++,CLC++,clc++1.0,CLC++1.0,clc++2021,CLC++2021">;
 def cl_denorms_are_zero : Flag<["-"], "cl-denorms-are-zero">, Group<opencl_Group>,
   HelpText<"OpenCL only. Allow denormals to be flushed to zero.">;
 def cl_fp32_correctly_rounded_divide_sqrt : Flag<["-"], "cl-fp32-correctly-rounded-divide-sqrt">, Group<opencl_Group>, Flags<[CC1Option]>,

clang/lib/Frontend/CompilerInvocation.cpp

@@ -3165,6 +3165,8 @@ void CompilerInvocation::setLangDefaults(LangOptions &Opts, InputKind IK,
     Opts.OpenCLVersion = 300;
   else if (LangStd == LangStandard::lang_openclcpp10)
     Opts.OpenCLCPlusPlusVersion = 100;
+  else if (LangStd == LangStandard::lang_openclcpp2021)
+    Opts.OpenCLCPlusPlusVersion = 202100;
 
   // OpenCL has some additional defaults.
   if (Opts.OpenCL) {
@@ -3314,6 +3316,7 @@ void CompilerInvocation::GenerateLangArgs(const LangOptions &Opts,
   case LangStandard::lang_opencl20:
   case LangStandard::lang_opencl30:
   case LangStandard::lang_openclcpp10:
+  case LangStandard::lang_openclcpp2021:
     StdOpt = OPT_cl_std_EQ;
     break;
   default:
@@ -3612,6 +3615,7 @@ bool CompilerInvocation::ParseLangArgs(LangOptions &Opts, ArgList &Args,
         .Cases("cl3.0", "CL3.0", LangStandard::lang_opencl30)
         .Cases("clc++", "CLC++", LangStandard::lang_openclcpp10)
         .Cases("clc++1.0", "CLC++1.0", LangStandard::lang_openclcpp10)
+        .Cases("clc++2021", "CLC++2021", LangStandard::lang_openclcpp2021)
         .Default(LangStandard::lang_unspecified);
 
     if (OpenCLLangStd == LangStandard::lang_unspecified) {

clang/lib/Frontend/InitPreprocessor.cpp

@@ -433,11 +433,18 @@ static void InitializeStandardPredefinedMacros(const TargetInfo &TI,
   // OpenCL v1.0/1.1 s6.9, v1.2/2.0 s6.10: Preprocessor Directives and Macros.
   if (LangOpts.OpenCL) {
     if (LangOpts.CPlusPlus) {
-      if (LangOpts.OpenCLCPlusPlusVersion == 100)
+      switch (LangOpts.OpenCLCPlusPlusVersion) {
+      case 100:
         Builder.defineMacro("__OPENCL_CPP_VERSION__", "100");
-      else
+        break;
+      case 202100:
+        Builder.defineMacro("__OPENCL_CPP_VERSION__", "202100");
+        break;
+      default:
         llvm_unreachable("Unsupported C++ version for OpenCL");
+      }
       Builder.defineMacro("__CL_CPP_VERSION_1_0__", "100");
+      Builder.defineMacro("__CL_CPP_VERSION_2021__", "202100");
     } else {
       // OpenCL v1.0 and v1.1 do not have a predefined macro to indicate the
       // language standard with which the program is compiled. __OPENCL_VERSION__

clang/test/Driver/autocomplete.c

@@ -51,6 +51,8 @@
 // CLSTDALL-NEXT: CLC++
 // CLSTDALL-NEXT: clc++1.0
 // CLSTDALL-NEXT: CLC++1.0
+// CLSTDALL-NEXT: clc++2021
+// CLSTDALL-NEXT: CLC++2021
 // RUN: %clang --autocomplete=-fno-sanitize-coverage=,f | FileCheck %s -check-prefix=FNOSANICOVER
 // FNOSANICOVER: func
 // RUN: %clang --autocomplete=-fno-sanitize-coverage= | FileCheck %s -check-prefix=FNOSANICOVERALL

clang/test/Driver/unknown-std.cl

@@ -12,6 +12,7 @@
 // CHECK-NEXT: note: use 'cl2.0' for 'OpenCL 2.0' standard
 // CHECK-NEXT: note: use 'cl3.0' for 'OpenCL 3.0' standard
 // CHECK-NEXT: note: use 'clc++1.0' or 'clc++' for 'C++ for OpenCL 1.0' standard
+// CHECK-NEXT: note: use 'clc++2021' for 'C++ for OpenCL 2021' standard
 
 // Make sure that no other output is present.
 // CHECK-NOT: {{^.+$}}

clang/test/Frontend/stdlang.c

@@ -7,12 +7,16 @@
 // RUN: %clang_cc1 -x cl -cl-std=cl2.0 -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=cl3.0 -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=clc++ -DOPENCL %s
+// RUN: %clang_cc1 -x cl -cl-std=clc++1.0 -DOPENCL %s
+// RUN: %clang_cc1 -x cl -cl-std=clc++2021 -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=CL -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=CL1.1 -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=CL1.2 -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=CL2.0 -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=CL3.0 -DOPENCL %s
 // RUN: %clang_cc1 -x cl -cl-std=CLC++ -DOPENCL %s
+// RUN: %clang_cc1 -x cl -cl-std=CLC++1.0 -DOPENCL %s
+// RUN: %clang_cc1 -x cl -cl-std=CLC++2021 -DOPENCL %s
 // RUN: not %clang_cc1 -x cl -std=c99 -DOPENCL %s 2>&1 | FileCheck --check-prefix=CHECK-C99 %s
 // RUN: not %clang_cc1 -x cl -cl-std=invalid -DOPENCL %s 2>&1 | FileCheck --check-prefix=CHECK-INVALID %s
 // CHECK-C99: error: invalid argument '-std=c99' not allowed with 'OpenCL'