Merge from 'main' to 'sycl-web' (#2)

  CONFLICT (content): Merge conflict in clang/test/Misc/nvptx.languageOptsOpenCL.cl

Author: asudarsa

clang/docs/LanguageExtensions.rst

@@ -1741,6 +1741,34 @@ OpenCL Features
 
 Clang supports internal OpenCL extensions documented below.
 
+``__cl_clang_bitfields``
+--------------------------------
+
+With this extension it is possible to enable bitfields in structs
+or unions using the OpenCL extension pragma mechanism detailed in
+`the OpenCL Extension Specification, section 1.2
+<https://www.khronos.org/registry/OpenCL/specs/3.0-unified/html/OpenCL_Ext.html#extensions-overview>`_.
+
+Use of bitfields in OpenCL kernels can result in reduced portability as struct
+layout is not guaranteed to be consistent when compiled by different compilers.
+If structs with bitfields are used as kernel function parameters, it can result
+in incorrect functionality when the layout is different between the host and
+device code.
+
+**Example of Use**:
+
+.. code-block:: c++
+
+  #pragma OPENCL EXTENSION __cl_clang_bitfields : enable
+  struct with_bitfield {
+    unsigned int i : 5; // compiled - no diagnostic generated
+  };
+
+  #pragma OPENCL EXTENSION __cl_clang_bitfields : disable
+  struct without_bitfield {
+    unsigned int i : 5; // error - bitfields are not supported
+  };
+
 ``__cl_clang_function_pointers``
 --------------------------------
 

clang/include/clang/Basic/OpenCLExtensions.def

@@ -88,6 +88,7 @@ OPENCL_EXTENSION(cl_clang_storage_class_specifiers, true, 100)
 OPENCL_EXTENSION(__cl_clang_function_pointers, true, 100)
 OPENCL_EXTENSION(__cl_clang_variadic_functions, true, 100)
 OPENCL_EXTENSION(__cl_clang_non_portable_kernel_param_types, true, 100)
+OPENCL_EXTENSION(__cl_clang_bitfields, true, 100)
 
 // AMD OpenCL extensions
 OPENCL_EXTENSION(cl_amd_media_ops, true, 100)

clang/lib/Analysis/CFG.cpp

@@ -1456,6 +1456,13 @@ void CFGBuilder::findConstructionContexts(
     // TODO: Handle other cases. For now, fail to find construction contexts.
     break;
   }
+  case Stmt::ParenExprClass: {
+    // If expression is placed into parenthesis we should propagate the parent
+    // construction context to subexpressions.
+    auto *PE = cast<ParenExpr>(Child);
+    findConstructionContexts(Layer, PE->getSubExpr());
+    break;
+  }
   default:
     break;
   }

clang/lib/Basic/Targets/AMDGPU.h

@@ -288,6 +288,7 @@ class LLVM_LIBRARY_VISIBILITY AMDGPUTargetInfo final : public TargetInfo {
     Opts["__cl_clang_variadic_functions"] = true;
     Opts["__cl_clang_function_pointers"] = true;
     Opts["__cl_clang_non_portable_kernel_param_types"] = true;
+    Opts["__cl_clang_bitfields"] = true;
 
     bool IsAMDGCN = isAMDGCN(getTriple());
 

clang/lib/Basic/Targets/NVPTX.h

@@ -136,6 +136,7 @@ class LLVM_LIBRARY_VISIBILITY NVPTXTargetInfo : public TargetInfo {
     Opts["__cl_clang_function_pointers"] = true;
     Opts["__cl_clang_variadic_functions"] = true;
     Opts["__cl_clang_non_portable_kernel_param_types"] = true;
+    Opts["__cl_clang_bitfields"] = true;
 
     Opts["cl_khr_fp64"] = true;
     Opts["__opencl_c_fp64"] = true;

clang/lib/CodeGen/CGDebugInfo.cpp

@@ -2996,8 +2996,13 @@ llvm::DIType *CGDebugInfo::CreateType(const LValueReferenceType *Ty,
 
 llvm::DIType *CGDebugInfo::CreateType(const RValueReferenceType *Ty,
                                       llvm::DIFile *Unit) {
-  return CreatePointerLikeType(llvm::dwarf::DW_TAG_rvalue_reference_type, Ty,
-                               Ty->getPointeeType(), Unit);
+  llvm::dwarf::Tag Tag = llvm::dwarf::DW_TAG_rvalue_reference_type;
+  // DW_TAG_rvalue_reference_type was introduced in DWARF 4.
+  if (CGM.getCodeGenOpts().DebugStrictDwarf &&
+      CGM.getCodeGenOpts().DwarfVersion < 4)
+    Tag = llvm::dwarf::DW_TAG_reference_type;
+
+  return CreatePointerLikeType(Tag, Ty, Ty->getPointeeType(), Unit);
 }
 
 llvm::DIType *CGDebugInfo::CreateType(const MemberPointerType *Ty,

clang/lib/Parse/ParseStmtAsm.cpp

@@ -577,20 +577,22 @@ StmtResult Parser::ParseMicrosoftAsmStatement(SourceLocation AsmLoc) {
       TheTarget->createMCAsmInfo(*MRI, TT, MCOptions));
   // Get the instruction descriptor.
   std::unique_ptr<llvm::MCInstrInfo> MII(TheTarget->createMCInstrInfo());
-  std::unique_ptr<llvm::MCObjectFileInfo> MOFI(new llvm::MCObjectFileInfo());
   std::unique_ptr<llvm::MCSubtargetInfo> STI(
       TheTarget->createMCSubtargetInfo(TT, TO.CPU, FeaturesStr));
   // Target MCTargetDesc may not be linked in clang-based tools.
-  if (!MAI || !MII || !MOFI || !STI) {
+
+  if (!MAI || !MII || !STI) {
     Diag(AsmLoc, diag::err_msasm_unable_to_create_target)
         << "target MC unavailable";
     return EmptyStmt();
   }
 
   llvm::SourceMgr TempSrcMgr;
-  llvm::MCContext Ctx(TheTriple, MAI.get(), MRI.get(), MOFI.get(), STI.get(),
-                      &TempSrcMgr);
-  MOFI->initMCObjectFileInfo(Ctx, /*PIC=*/false);
+  llvm::MCContext Ctx(TheTriple, MAI.get(), MRI.get(), STI.get(), &TempSrcMgr);
+  std::unique_ptr<llvm::MCObjectFileInfo> MOFI(
+      TheTarget->createMCObjectFileInfo(Ctx, /*PIC=*/false));
+  Ctx.setObjectFileInfo(MOFI.get());
+
   std::unique_ptr<llvm::MemoryBuffer> Buffer =
       llvm::MemoryBuffer::getMemBuffer(AsmString, "<MS inline asm>");
 

clang/lib/Sema/SemaDecl.cpp

@@ -16881,8 +16881,10 @@ FieldDecl *Sema::CheckFieldDecl(DeclarationName Name, QualType T,
       Record->setInvalidDecl();
       InvalidDecl = true;
     }
-    // OpenCL v1.2 s6.9.c: bitfields are not supported.
-    if (BitWidth) {
+    // OpenCL v1.2 s6.9.c: bitfields are not supported, unless Clang extension
+    // is enabled.
+    if (BitWidth && !getOpenCLOptions().isAvailableOption(
+                        "__cl_clang_bitfields", LangOpts)) {
       Diag(Loc, diag::err_opencl_bitfields);
       InvalidDecl = true;
     }