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 #include "llvm/ADT/StringRef.h"
19 
20 namespace llvm {
21 class Function;
22 class GlobalVariable;
23 }
24 
25 namespace clang {
26 
27 class CUDAKernelCallExpr;
28 class VarDecl;
29 
30 namespace CodeGen {
31 
32 class CodeGenFunction;
33 class CodeGenModule;
34 class FunctionArgList;
35 class ReturnValueSlot;
36 class RValue;
37 
38 class CGCUDARuntime {
39 protected:
40   CodeGenModule &CGM;
41 
42 public:
43   // Global variable properties that must be passed to CUDA runtime.
44   enum DeviceVarFlags {
45     ExternDeviceVar = 0x01,   // extern
46     ConstantDeviceVar = 0x02, // __constant__
47   };
48 
CGCUDARuntime(CodeGenModule & CGM)49   CGCUDARuntime(CodeGenModule &CGM) : CGM(CGM) {}
50   virtual ~CGCUDARuntime();
51 
52   virtual RValue EmitCUDAKernelCallExpr(CodeGenFunction &CGF,
53                                         const CUDAKernelCallExpr *E,
54                                         ReturnValueSlot ReturnValue);
55 
56   /// Emits a kernel launch stub.
57   virtual void emitDeviceStub(CodeGenFunction &CGF, FunctionArgList &Args) = 0;
58   virtual void registerDeviceVar(const VarDecl *VD, llvm::GlobalVariable &Var,
59                                  unsigned Flags) = 0;
60 
61   /// Constructs and returns a module initialization function or nullptr if it's
62   /// not needed. Must be called after all kernels have been emitted.
63   virtual llvm::Function *makeModuleCtorFunction() = 0;
64 
65   /// Returns a module cleanup function or nullptr if it's not needed.
66   /// Must be called after ModuleCtorFunction
67   virtual llvm::Function *makeModuleDtorFunction() = 0;
68 
69   /// Construct and return the stub name of a kernel.
70   virtual std::string getDeviceStubName(llvm::StringRef Name) const = 0;
71 };
72 
73 /// Creates an instance of a CUDA runtime class.
74 CGCUDARuntime *CreateNVCUDARuntime(CodeGenModule &CGM);
75 
76 }
77 }
78 
79 #endif
80