1 //===----- CGCUDARuntime.h - Interface to CUDA Runtimes ---------*- C++ -*-===//
2 //
3 // Part of the LLVM Project, under the Apache License v2.0 with LLVM Exceptions.
4 // See https://llvm.org/LICENSE.txt for license information.
5 // SPDX-License-Identifier: Apache-2.0 WITH LLVM-exception
6 //
7 //===----------------------------------------------------------------------===//
8 //
9 // This provides an abstract class for CUDA code generation.  Concrete
10 // subclasses of this implement code generation for specific CUDA
11 // runtime libraries.
12 //
13 //===----------------------------------------------------------------------===//
14 
15 #ifndef LLVM_CLANG_LIB_CODEGEN_CGCUDARUNTIME_H
16 #define LLVM_CLANG_LIB_CODEGEN_CGCUDARUNTIME_H
17 
18 namespace llvm {
19 class Function;
20 class GlobalVariable;
21 }
22 
23 namespace clang {
24 
25 class CUDAKernelCallExpr;
26 class VarDecl;
27 
28 namespace CodeGen {
29 
30 class CodeGenFunction;
31 class CodeGenModule;
32 class FunctionArgList;
33 class ReturnValueSlot;
34 class RValue;
35 
36 class CGCUDARuntime {
37 protected:
38   CodeGenModule &CGM;
39 
40 public:
41   // Global variable properties that must be passed to CUDA runtime.
42   enum DeviceVarFlags {
43     ExternDeviceVar = 0x01,   // extern
44     ConstantDeviceVar = 0x02, // __constant__
45   };
46 
47   CGCUDARuntime(CodeGenModule &CGM) : CGM(CGM) {}
48   virtual ~CGCUDARuntime();
49 
50   virtual RValue EmitCUDAKernelCallExpr(CodeGenFunction &CGF,
51                                         const CUDAKernelCallExpr *E,
52                                         ReturnValueSlot ReturnValue);
53 
54   /// Emits a kernel launch stub.
55   virtual void emitDeviceStub(CodeGenFunction &CGF, FunctionArgList &Args) = 0;
56   virtual void registerDeviceVar(const VarDecl *VD, llvm::GlobalVariable &Var,
57                                  unsigned Flags) = 0;
58 
59   /// Constructs and returns a module initialization function or nullptr if it's
60   /// not needed. Must be called after all kernels have been emitted.
61   virtual llvm::Function *makeModuleCtorFunction() = 0;
62 
63   /// Returns a module cleanup function or nullptr if it's not needed.
64   /// Must be called after ModuleCtorFunction
65   virtual llvm::Function *makeModuleDtorFunction() = 0;
66 };
67 
68 /// Creates an instance of a CUDA runtime class.
69 CGCUDARuntime *CreateNVCUDARuntime(CodeGenModule &CGM);
70 
71 }
72 }
73 
74 #endif
75