[SYCL] Enable FPGA memory attributes

This patch introduces the following FPGA memory attributes:
* register
* memory
* numbanks
* bankwidth

Signed-off-by: Vladimir Lazarev <vladimir.lazarev@intel.com>
Signed-off-by: Viktoria Maksimova <viktoria.maksimova@intel.com>

clang/include/clang/Basic/Attr.td

@@ -1387,6 +1387,93 @@ def Mode : Attr {
   let PragmaAttributeSupport = 0;
 }
 
+def IntelFPGAConstVar : SubsetSubject<Var,
+                      [{S->getKind() != Decl::ImplicitParam &&
+                        S->getKind() != Decl::ParmVar &&
+                        S->getKind() != Decl::NonTypeTemplateParm &&
+                        (S->getType().isConstQualified() ||
+                         S->getType().getAddressSpace() ==
+                            LangAS::opencl_constant)}],
+                      "constant variables">;
+
+def IntelFPGALocalStaticSlaveMemVar : SubsetSubject<Var,
+      [{S->getKind() != Decl::ImplicitParam &&
+        S->getKind() != Decl::NonTypeTemplateParm &&
+        (S->getStorageClass() == SC_Static ||
+         S->hasLocalStorage())}],
+         "local variables, static variables, slave memory arguments">;
+
+def IntelFPGALocalOrStaticVar : SubsetSubject<Var,
+                              [{S->getKind() != Decl::ImplicitParam &&
+                                S->getKind() != Decl::ParmVar &&
+                                S->getKind() != Decl::NonTypeTemplateParm &&
+                                (S->getStorageClass() == SC_Static ||
+                                 S->hasLocalStorage())}],
+                              "local variables, static variables">;
+
+def IntelFPGAMemory : Attr {
+  let Spellings = [GNU<"memory">, CXX11<"intelfpga", "memory">];
+  let Args = [EnumArgument<"Kind", "MemoryKind",
+                           ["MLAB", "BLOCK_RAM", ""],
+                           ["MLAB", "BlockRAM", "Default"], 1>];
+  let AdditionalMembers = [{
+    static void generateValidStrings(SmallString<256> &Str) {
+      auto Last = BlockRAM;
+      for (int I = 0; I <= Last; ++I) {
+        Str += ConvertMemoryKindToStr(static_cast<MemoryKind>(I));
+        if (I != Last) Str += " ";
+      }
+    }
+  }];
+  let Subjects = SubjectList<[IntelFPGAConstVar, IntelFPGALocalStaticSlaveMemVar,
+                              Field], ErrorDiag>;
+  let LangOpts = [SYCL];
+  let Documentation = [IntelFPGAMemoryAttrDocs];
+}
+
+def IntelFPGARegister : Attr {
+  let Spellings = [GNU<"register">, CXX11<"intelfpga", "register">];
+  let Subjects = SubjectList<[IntelFPGAConstVar, IntelFPGALocalOrStaticVar,
+                              Field], ErrorDiag>;
+  let LangOpts = [SYCL];
+  let Documentation = [IntelFPGARegisterAttrDocs];
+}
+
+// One integral argument.
+def IntelFPGABankWidth : Attr {
+  let Spellings = [GNU<"bankwidth">, CXX11<"intelfpga","bankwidth">];
+  let Args = [ExprArgument<"Value">];
+  let Subjects = SubjectList<[IntelFPGAConstVar, IntelFPGALocalStaticSlaveMemVar,
+                              Field], ErrorDiag>;
+  let LangOpts = [SYCL];
+  let Documentation = [IntelFPGABankWidthAttrDocs];
+  let AdditionalMembers = [{
+    static unsigned getMinValue() {
+      return 1;
+    }
+    static unsigned getMaxValue() {
+      return 1024*1024;
+    }
+  }];
+}
+
+def IntelFPGANumBanks : Attr {
+  let Spellings = [GNU<"numbanks">, CXX11<"intelfpga","numbanks">];
+  let Args = [ExprArgument<"Value">];
+  let Subjects = SubjectList<[IntelFPGAConstVar, IntelFPGALocalStaticSlaveMemVar,
+                              Field], ErrorDiag>;
+  let LangOpts = [SYCL];
+  let Documentation = [IntelFPGANumBanksAttrDocs];
+  let AdditionalMembers = [{
+    static unsigned getMinValue() {
+      return 1;
+    }
+    static unsigned getMaxValue() {
+      return 1024*1024;
+    }
+  }];
+}
+
 def Naked : InheritableAttr {
   let Spellings = [GCC<"naked">, Declspec<"naked">];
   let Subjects = SubjectList<[Function]>;

clang/include/clang/Basic/AttrDocs.td

@@ -1668,6 +1668,47 @@ as ``-mlong-calls`` and ``-mno-long-calls``.
   }];
 }
 
+def IntelFPGAMemoryAttrDocs : Documentation {
+  let Category = DocCatVariable;
+  let Heading = "memory (IntelFGPA)";
+  let Content = [{
+This attribute may be attached to a variable or struct member declaration and
+instructs the backend to implement the variable or struct member in memory
+rather than promoting to register(s).  If the optional parameter is specified
+it indicates what type of memory to use.
+  }];
+}
+
+def IntelFPGARegisterAttrDocs : Documentation {
+  let Category = DocCatVariable;
+  let Heading = "register (IntelFGPA)";
+  let Content = [{
+This attribute may be attached to a variable or struct member declaration and
+instructs the backend to promote the variable or struct member to register(s)
+if possible.
+  }];
+}
+
+def IntelFPGABankWidthAttrDocs : Documentation {
+  let Category = DocCatVariable;
+  let Heading = "bankwidth (IntelFGPA)";
+  let Content = [{
+This attribute may be attached to a variable or struct member declaration and
+instructs the backend to implement the variable or struct member in a memory
+with banks that are N bytes wide.
+  }];
+}
+
+def IntelFPGANumBanksAttrDocs : Documentation {
+  let Category = DocCatVariable;
+  let Heading = "numbanks (IntelFGPA)";
+  let Content = [{
+This attribute may be attached to a variable or struct member declaration and
+instructs the backend to implement the variable or struct member in a memory
+with N banks.
+  }];
+}
+
 def RISCVInterruptDocs : Documentation {
   let Category = DocCatFunction;
   let Heading = "interrupt (RISCV)";

clang/include/clang/Basic/DiagnosticSemaKinds.td

@@ -123,6 +123,12 @@ def warn_double_const_requires_fp64 : Warning<
 def err_half_const_requires_fp16 : Error<
   "half precision constant requires cl_khr_fp16">;
 
+// Intel FPGA extensions
+def err_attribute_argument_not_power_of_two : Error<
+  "%0 attribute argument must be a constant power of two greater than zero">;
+def err_intel_fpga_memory_arg_invalid : Error<
+  "%0 attribute requires either no argument or one of: %1">;
+
 // C99 variable-length arrays
 def ext_vla : Extension<"variable length arrays are a C99 feature">,
   InGroup<VLAExtension>;

clang/include/clang/Sema/Sema.h

@@ -8751,6 +8751,13 @@ class Sema {
   /// attribute to be added (usually because of a pragma).
   void AddOptnoneAttributeIfNoConflicts(FunctionDecl *FD, SourceLocation Loc);
 
+  template <typename AttrType>
+  bool checkRangedIntegralArgument(Expr *E, const AttrType *TmpAttr,
+                                   ExprResult &Result);
+  template <typename AttrType>
+  void AddOneConstantPowerTwoValueAttr(SourceRange AttrRange, Decl *D, Expr *E,
+                                       unsigned SpellingListIndex);
+
   /// AddAlignedAttr - Adds an aligned attribute to a particular declaration.
   void AddAlignedAttr(SourceRange AttrRange, Decl *D, Expr *E,
                       unsigned SpellingListIndex, bool IsPackExpansion);

clang/lib/CodeGen/CGDecl.cpp

@@ -1607,6 +1607,18 @@ CodeGenFunction::EmitAutoVarAlloca(const VarDecl &D) {
     (void)DI->EmitDeclareOfAutoVariable(&D, address.getPointer(), Builder);
   }
 
+  // Emit Intel FPGA attribute annotation for a local variable.
+  if (getLangOpts().SYCLIsDevice) {
+    SmallString<256> AnnotStr;
+    CGM.generateIntelFPGAAnnotation(&D, AnnotStr);
+    if (!AnnotStr.empty()) {
+      llvm::Value *V = address.getPointer();
+      EmitAnnotationCall(CGM.getIntrinsic(llvm::Intrinsic::var_annotation),
+                         Builder.CreateBitCast(V, CGM.Int8PtrTy, V->getName()),
+                         AnnotStr, D.getLocation());
+    }
+  }
+
   if (D.hasAttr<AnnotateAttr>() && HaveInsertPoint())
     EmitVarAnnotations(&D, address.getPointer());
 

clang/lib/CodeGen/CGExpr.cpp

@@ -3958,6 +3958,14 @@ LValue CodeGenFunction::EmitLValueForField(LValue base,
   if (field->hasAttr<AnnotateAttr>())
     addr = EmitFieldAnnotations(field, addr);
 
+  // Emit attribute annotation for a field.
+  if (getLangOpts().SYCLIsDevice) {
+    SmallString<256> AnnotStr;
+    CGM.generateIntelFPGAAnnotation(field, AnnotStr);
+    if (!AnnotStr.empty())
+      addr = EmitIntelFPGAFieldAnnotations(field, addr, AnnotStr);
+  }
+
   LValue LV = MakeAddrLValue(addr, FieldType, FieldBaseInfo, FieldTBAAInfo);
   LV.getQuals().addCVRQualifiers(RecordCVR);
 

clang/lib/CodeGen/CodeGenFunction.cpp

@@ -2293,6 +2293,23 @@ Address CodeGenFunction::EmitFieldAnnotations(const FieldDecl *D,
   return Address(V, Addr.getAlignment());
 }
 
+Address CodeGenFunction::EmitIntelFPGAFieldAnnotations(const FieldDecl *D,
+                                                       Address Addr,
+                                                       StringRef AnnotStr) {
+  llvm::Value *V = Addr.getPointer();
+  llvm::Type *VTy = V->getType();
+  llvm::Function *F =
+      CGM.getIntrinsic(llvm::Intrinsic::ptr_annotation, CGM.Int8PtrTy);
+  // FIXME Always emit the cast inst so we can differentiate between
+  // annotation on the first field of a struct and annotation on the struct
+  // itself.
+  if (VTy != CGM.Int8PtrTy)
+    V = Builder.CreateBitCast(V, CGM.Int8PtrTy);
+  V = EmitAnnotationCall(F, V, AnnotStr, D->getLocation());
+  V = Builder.CreateBitCast(V, VTy);
+  return Address(V, Addr.getAlignment());
+}
+
 CodeGenFunction::CGCapturedStmtInfo::~CGCapturedStmtInfo() { }
 
 CodeGenFunction::SanitizerScope::SanitizerScope(CodeGenFunction *CGF)

clang/lib/CodeGen/CodeGenFunction.h

@@ -4009,6 +4009,10 @@ class CodeGenFunction : public CodeGenTypeCache {
   /// annotation result.
   Address EmitFieldAnnotations(const FieldDecl *D, Address V);
 
+  /// Emit Intel FPGA field annotations for the given field and value. Returns
+  /// the annotation result.
+  Address EmitIntelFPGAFieldAnnotations(const FieldDecl *D, Address V,
+                                        StringRef AnnotStr);
   //===--------------------------------------------------------------------===//
   //                             Internal Helpers
   //===--------------------------------------------------------------------===//

clang/lib/CodeGen/CodeGenModule.cpp

@@ -3512,6 +3512,55 @@ void CodeGenModule::maybeSetTrivialComdat(const Decl &D,
   GO.setComdat(TheModule.getOrInsertComdat(GO.getName()));
 }
 
+void CodeGenModule::generateIntelFPGAAnnotation(
+    const Decl *D, llvm::SmallString<256> &AnnotStr) {
+  llvm::raw_svector_ostream Out(AnnotStr);
+  if (D->hasAttr<IntelFPGARegisterAttr>())
+    Out << "{register:1}";
+  if (auto const *MA = D->getAttr<IntelFPGAMemoryAttr>()) {
+    IntelFPGAMemoryAttr::MemoryKind Kind = MA->getKind();
+    Out << "{memory:";
+    switch (Kind) {
+    case IntelFPGAMemoryAttr::MLAB:
+    case IntelFPGAMemoryAttr::BlockRAM:
+      Out << IntelFPGAMemoryAttr::ConvertMemoryKindToStr(Kind);
+      break;
+    case IntelFPGAMemoryAttr::Default:
+      Out << "DEFAULT";
+      break;
+    }
+    Out << '}';
+  }
+  if (const auto *BWA = D->getAttr<IntelFPGABankWidthAttr>()) {
+    llvm::APSInt BWAInt = BWA->getValue()->EvaluateKnownConstInt(getContext());
+    Out << '{' << BWA->getSpelling() << ':' << BWAInt << '}';
+  }
+  if (const auto *NBA = D->getAttr<IntelFPGANumBanksAttr>()) {
+    llvm::APSInt BWAInt = NBA->getValue()->EvaluateKnownConstInt(getContext());
+    Out << '{' << NBA->getSpelling() << ':' << BWAInt << '}';
+  }
+}
+
+void CodeGenModule::addGlobalIntelFPGAAnnotation(const VarDecl *VD,
+                                                 llvm::GlobalValue *GV) {
+  SmallString<256> AnnotStr;
+  generateIntelFPGAAnnotation(VD, AnnotStr);
+  if (!AnnotStr.empty()) {
+    // Get the globals for file name, annotation, and the line number.
+    llvm::Constant *AnnoGV = EmitAnnotationString(AnnotStr),
+                   *UnitGV = EmitAnnotationUnit(VD->getLocation()),
+                   *LineNoCst = EmitAnnotationLineNo(VD->getLocation());
+
+    llvm::Constant *C =
+        llvm::ConstantExpr::getPointerBitCastOrAddrSpaceCast(GV, Int8PtrTy);
+    // Create the ConstantStruct for the global annotation.
+    llvm::Constant *Fields[4] = {
+        C, llvm::ConstantExpr::getBitCast(AnnoGV, Int8PtrTy),
+        llvm::ConstantExpr::getBitCast(UnitGV, Int8PtrTy), LineNoCst};
+    Annotations.push_back(llvm::ConstantStruct::getAnon(Fields));
+  }
+}
+
 /// Pass IsTentative as true if you want to create a tentative definition.
 void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
                                             bool IsTentative) {
@@ -3638,6 +3687,21 @@ void CodeGenModule::EmitGlobalVarDefinition(const VarDecl *D,
   if (D->hasAttr<AnnotateAttr>())
     AddGlobalAnnotations(D, GV);
 
+  // Emit Intel FPGA attribute annotation for a file-scope static variable.
+  if (getLangOpts().SYCLIsDevice)
+    addGlobalIntelFPGAAnnotation(D, GV);
+
+  if (D->getType().isRestrictQualified()) {
+    llvm::LLVMContext &Context = getLLVMContext();
+
+    // Common metadata nodes.
+    llvm::NamedMDNode *GlobalsRestrict =
+        getModule().getOrInsertNamedMetadata("globals.restrict");
+    llvm::Metadata *Args[] = {llvm::ValueAsMetadata::get(GV)};
+    llvm::MDNode *Node = llvm::MDNode::get(Context, Args);
+    GlobalsRestrict->addOperand(Node);
+  }
+
   // Set the llvm linkage type as appropriate.
   llvm::GlobalValue::LinkageTypes Linkage =
       getLLVMLinkageVarDefinition(D, GV->isConstant());

clang/lib/CodeGen/CodeGenModule.h

@@ -976,6 +976,10 @@ class CodeGenModule : public CodeGenTypeCache {
       llvm::FunctionType *FnType = nullptr, bool DontDefer = false,
       ForDefinition_t IsForDefinition = NotForDefinition);
 
+  void generateIntelFPGAAnnotation(const Decl *D,
+                                     llvm::SmallString<256> &AnnotStr);
+  void addGlobalIntelFPGAAnnotation(const VarDecl *VD, llvm::GlobalValue *GV);
+
   /// Given a builtin id for a function like "__builtin_fabsf", return a
   /// Function* for "fabsf".
   llvm::Constant *getBuiltinLibFunction(const FunctionDecl *FD,