[IR] Move support for dxil::TypedPointerType to LLVM core IR.

This allows the construct to be shared between different backends. However, it
still remains illegal to use TypedPointerType in LLVM IR--the type is intended
to remain an auxiliary type, not a real LLVM type. So no support is provided for
LLVM-C, nor bitcode, nor LLVM assembly (besides the bare minimum needed to make
Type->dump() work properly).

Reviewed By: beanz, nikic, aeubanks

Differential Revision: https://reviews.llvm.org/D130592

Author: jcranmer-intel

llvm/include/llvm/IR/LLVMContext.h

@@ -24,7 +24,6 @@
 
 namespace llvm {
 
-class Any;
 class DiagnosticInfo;
 enum DiagnosticSeverity : char;
 class Function;
@@ -323,10 +322,6 @@ class LLVMContext {
   /// Whether typed pointers are supported. If false, all pointers are opaque.
   bool supportsTypedPointers() const;
 
-  /// Optionally target-spcific data can be attached to the context for lifetime
-  /// management and bypassing layering restrictions.
-  llvm::Any &getTargetData() const;
-
 private:
   // Module needs access to the add/removeModule methods.
   friend class Module;

llvm/include/llvm/IR/Type.h

@@ -75,7 +75,7 @@ class Type {
     ArrayTyID,          ///< Arrays
     FixedVectorTyID,    ///< Fixed width SIMD vector type
     ScalableVectorTyID, ///< Scalable SIMD vector type
-    DXILPointerTyID,    ///< DXIL typed pointer used by DirectX target
+    TypedPointerTyID,   ///< Typed pointer used by some GPU targets
   };
 
 private:

llvm/lib/Target/DirectX/DXILPointerType.h renamed to llvm/include/llvm/IR/TypedPointerType.h

@@ -1,24 +1,27 @@
-//===- Target/DirectX/DXILPointerType.h - DXIL Typed Pointer Type ---------===//
+//===- llvm/IR/TypedPointerType.h - Typed Pointer Type --------------------===//
 //
 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
 // See https://llvm.org/LICENSE.txt for license information.
 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
 //
 //===----------------------------------------------------------------------===//
 //
+// This file contains typed pointer type information. It is separated out into
+// a separate file to make it less likely to accidentally use this type.
 //
 //===----------------------------------------------------------------------===//
 
-#ifndef LLVM_TARGET_DIRECTX_DXILPOINTERTYPE_H
-#define LLVM_TARGET_DIRECTX_DXILPOINTERTYPE_H
+#ifndef LLVM_IR_TYPEDPOINTERTYPE_H
+#define LLVM_IR_TYPEDPOINTERTYPE_H
 
 #include "llvm/IR/Type.h"
 
 namespace llvm {
-namespace dxil {
 
-// DXIL has typed pointers, this pointer type abstraction is used for tracking
-// in PointerTypeAnalysis and for the bitcode ValueEnumerator
+/// A few GPU targets, such as DXIL and SPIR-V, have typed pointers. This
+/// pointer type abstraction is used for tracking the types of these pointers.
+/// It is not legal to use this type, or derived types containing this type, in
+/// LLVM IR.
 class TypedPointerType : public Type {
   explicit TypedPointerType(Type *ElType, unsigned AddrSpace);
 
@@ -42,11 +45,10 @@ class TypedPointerType : public Type {
 
   /// Implement support type inquiry through isa, cast, and dyn_cast.
   static bool classof(const Type *T) {
-    return T->getTypeID() == DXILPointerTyID;
+    return T->getTypeID() == TypedPointerTyID;
   }
 };
 
-} // namespace dxil
 } // namespace llvm
 
-#endif // LLVM_TARGET_DIRECTX_DXILPOINTERTYPE_H
+#endif // LLVM_IR_TYPEDPOINTERTYPE_H

llvm/lib/Bitcode/Writer/BitcodeWriter.cpp

@@ -1029,8 +1029,8 @@ void ModuleBitcodeWriter::writeTypeTable() {
         TypeVals.push_back(true);
       break;
     }
-    case Type::DXILPointerTyID:
-      llvm_unreachable("DXIL pointers cannot be added to IR modules");
+    case Type::TypedPointerTyID:
+      llvm_unreachable("Typed pointers cannot be added to IR modules");
     }
 
     // Emit the finished record.

llvm/lib/IR/AsmWriter.cpp

@@ -62,6 +62,7 @@
 #include "llvm/IR/Operator.h"
 #include "llvm/IR/Type.h"
 #include "llvm/IR/TypeFinder.h"
+#include "llvm/IR/TypedPointerType.h"
 #include "llvm/IR/Use.h"
 #include "llvm/IR/User.h"
 #include "llvm/IR/Value.h"
@@ -610,12 +611,13 @@ void TypePrinting::print(Type *Ty, raw_ostream &OS) {
     OS << '>';
     return;
   }
-  case Type::DXILPointerTyID:
-    // DXIL pointer types are only handled by the DirectX backend. To avoid
-    // extra dependencies we just print the pointer's address here.
-    OS << "dxil-ptr (" << Ty << ")";
+  case Type::TypedPointerTyID: {
+    TypedPointerType *TPTy = cast<TypedPointerType>(Ty);
+    OS << "typedptr(" << *TPTy->getElementType() << ", "
+       << TPTy->getAddressSpace() << ")";
     return;
   }
+  }
   llvm_unreachable("Invalid TypeID");
 }
 

llvm/lib/IR/CMakeLists.txt

@@ -57,6 +57,7 @@ add_llvm_component_library(LLVMCore
   Statepoint.cpp
   StructuralHash.cpp
   Type.cpp
+  TypedPointerType.cpp
   TypeFinder.cpp
   Use.cpp
   User.cpp

llvm/lib/IR/Core.cpp

@@ -541,8 +541,8 @@ LLVMTypeKind LLVMGetTypeKind(LLVMTypeRef Ty) {
     return LLVMTokenTypeKind;
   case Type::ScalableVectorTyID:
     return LLVMScalableVectorTypeKind;
-  case Type::DXILPointerTyID:
-    llvm_unreachable("DXIL pointers are unsupported via the C API");
+  case Type::TypedPointerTyID:
+    llvm_unreachable("Typed pointers are unsupported via the C API");
   }
   llvm_unreachable("Unhandled TypeID.");
 }

llvm/lib/IR/LLVMContext.cpp

@@ -374,7 +374,3 @@ void LLVMContext::setOpaquePointers(bool Enable) const {
 bool LLVMContext::supportsTypedPointers() const {
   return !pImpl->getOpaquePointers();
 }
-
-Any &LLVMContext::getTargetData() const {
-  return pImpl->TargetDataStorage;
-}

llvm/lib/IR/LLVMContextImpl.h

@@ -70,6 +70,7 @@ class RemarkStreamer;
 }
 template <typename T> class StringMapEntry;
 class StringRef;
+class TypedPointerType;
 class ValueHandleBase;
 
 using DenseMapAPIntKeyInfo = DenseMapInfo<APInt>;
@@ -1484,6 +1485,7 @@ class LLVMContextImpl {
   DenseMap<std::pair<Type *, ElementCount>, VectorType *> VectorTypes;
   DenseMap<Type *, PointerType *> PointerTypes; // Pointers in AddrSpace = 0
   DenseMap<std::pair<Type *, unsigned>, PointerType *> ASPointerTypes;
+  DenseMap<std::pair<Type *, unsigned>, TypedPointerType *> ASTypedPointerTypes;
 
   /// ValueHandles - This map keeps track of all of the value handles that are
   /// watching a Value*.  The Value::HasValueHandle bit is used to know
@@ -1571,8 +1573,6 @@ class LLVMContextImpl {
   bool hasOpaquePointersValue();
   void setOpaquePointers(bool OP);
 
-  llvm::Any TargetDataStorage;
-
 private:
   Optional<bool> OpaquePointers;
 };

llvm/lib/IR/TypedPointerType.cpp

@@ -0,0 +1,43 @@
+//===- TypedPointerType.cpp - Typed Pointer Type --------------------------===//
+//
+// Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
+// See https://llvm.org/LICENSE.txt for license information.
+// SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
+//
+//===----------------------------------------------------------------------===//
+//
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/IR/TypedPointerType.h"
+#include "LLVMContextImpl.h"
+
+using namespace llvm;
+
+TypedPointerType *TypedPointerType::get(Type *EltTy, unsigned AddressSpace) {
+  assert(EltTy && "Can't get a pointer to <null> type!");
+  assert(isValidElementType(EltTy) && "Invalid type for pointer element!");
+
+  LLVMContextImpl *CImpl = EltTy->getContext().pImpl;
+
+  // Since AddressSpace #0 is the common case, we special case it.
+  TypedPointerType *&Entry =
+      CImpl->ASTypedPointerTypes[std::make_pair(EltTy, AddressSpace)];
+
+  if (!Entry)
+    Entry = new (CImpl->Alloc) TypedPointerType(EltTy, AddressSpace);
+  return Entry;
+}
+
+TypedPointerType::TypedPointerType(Type *E, unsigned AddrSpace)
+    : Type(E->getContext(), TypedPointerTyID), PointeeTy(E) {
+  ContainedTys = &PointeeTy;
+  NumContainedTys = 1;
+  setSubclassData(AddrSpace);
+}
+
+bool TypedPointerType::isValidElementType(Type *ElemTy) {
+  return !ElemTy->isVoidTy() && !ElemTy->isLabelTy() &&
+         !ElemTy->isMetadataTy() && !ElemTy->isTokenTy() &&
+         !ElemTy->isX86_AMXTy();
+}