1//===----- ABIInfo.h - ABI information access & encapsulation ---*- 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#ifndef LLVM_CLANG_LIB_CODEGEN_ABIINFO_H
10#define LLVM_CLANG_LIB_CODEGEN_ABIINFO_H
11
12#include "clang/AST/CharUnits.h"
13#include "clang/AST/Type.h"
14#include "llvm/IR/CallingConv.h"
15#include "llvm/IR/Type.h"
16
17namespace llvm {
18 class Value;
19 class LLVMContext;
20 class DataLayout;
21 class Type;
22}
23
24namespace clang {
25 class ASTContext;
26 class CodeGenOptions;
27 class TargetInfo;
28
29namespace CodeGen {
30 class ABIArgInfo;
31 class Address;
32 class CGCXXABI;
33 class CGFunctionInfo;
34 class CodeGenFunction;
35 class CodeGenTypes;
36 class SwiftABIInfo;
37
38namespace swiftcall {
39 class SwiftAggLowering;
40}
41
42 // FIXME: All of this stuff should be part of the target interface
43 // somehow. It is currently here because it is not clear how to factor
44 // the targets to support this, since the Targets currently live in a
45 // layer below types n'stuff.
46
47
48 /// ABIInfo - Target specific hooks for defining how a type should be
49 /// passed or returned from functions.
50 class ABIInfo {
51 public:
52 CodeGen::CodeGenTypes &CGT;
53 protected:
54 llvm::CallingConv::ID RuntimeCC;
55 public:
56 ABIInfo(CodeGen::CodeGenTypes &cgt)
57 : CGT(cgt), RuntimeCC(llvm::CallingConv::C) {}
58
59 virtual ~ABIInfo();
60
61 virtual bool supportsSwift() const { return false; }
62
63 virtual bool allowBFloatArgsAndRet() const { return false; }
64
65 CodeGen::CGCXXABI &getCXXABI() const;
66 ASTContext &getContext() const;
67 llvm::LLVMContext &getVMContext() const;
68 const llvm::DataLayout &getDataLayout() const;
69 const TargetInfo &getTarget() const;
70 const CodeGenOptions &getCodeGenOpts() const;
71
72 /// Return the calling convention to use for system runtime
73 /// functions.
74 llvm::CallingConv::ID getRuntimeCC() const {
75 return RuntimeCC;
76 }
77
78 virtual void computeInfo(CodeGen::CGFunctionInfo &FI) const = 0;
79
80 /// EmitVAArg - Emit the target dependent code to load a value of
81 /// \arg Ty from the va_list pointed to by \arg VAListAddr.
82
83 // FIXME: This is a gaping layering violation if we wanted to drop
84 // the ABI information any lower than CodeGen. Of course, for
85 // VAArg handling it has to be at this level; there is no way to
86 // abstract this out.
87 virtual CodeGen::Address EmitVAArg(CodeGen::CodeGenFunction &CGF,
88 CodeGen::Address VAListAddr,
89 QualType Ty) const = 0;
90
91 bool isAndroid() const;
92
93 /// Emit the target dependent code to load a value of
94 /// \arg Ty from the \c __builtin_ms_va_list pointed to by \arg VAListAddr.
95 virtual CodeGen::Address EmitMSVAArg(CodeGen::CodeGenFunction &CGF,
96 CodeGen::Address VAListAddr,
97 QualType Ty) const;
98
99 virtual bool isHomogeneousAggregateBaseType(QualType Ty) const;
100
101 virtual bool isHomogeneousAggregateSmallEnough(const Type *Base,
102 uint64_t Members) const;
103
104 bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
105 uint64_t &Members) const;
106
107 // Implement the Type::IsPromotableIntegerType for ABI specific needs. The
108 // only difference is that this considers _ExtInt as well.
109 bool isPromotableIntegerTypeForABI(QualType Ty) const;
110
111 /// A convenience method to return an indirect ABIArgInfo with an
112 /// expected alignment equal to the ABI alignment of the given type.
113 CodeGen::ABIArgInfo
114 getNaturalAlignIndirect(QualType Ty, bool ByVal = true,
115 bool Realign = false,
116 llvm::Type *Padding = nullptr) const;
117
118 CodeGen::ABIArgInfo
119 getNaturalAlignIndirectInReg(QualType Ty, bool Realign = false) const;
120
121
122 };
123
124 /// A refining implementation of ABIInfo for targets that support swiftcall.
125 ///
126 /// If we find ourselves wanting multiple such refinements, they'll probably
127 /// be independent refinements, and we should probably find another way
128 /// to do it than simple inheritance.
129 class SwiftABIInfo : public ABIInfo {
130 public:
131 SwiftABIInfo(CodeGen::CodeGenTypes &cgt) : ABIInfo(cgt) {}
132
133 bool supportsSwift() const final override { return true; }
134
135 virtual bool shouldPassIndirectlyForSwift(ArrayRef<llvm::Type*> types,
136 bool asReturnValue) const = 0;
137
138 virtual bool isLegalVectorTypeForSwift(CharUnits totalSize,
139 llvm::Type *eltTy,
140 unsigned elts) const;
141
142 virtual bool isSwiftErrorInRegister() const = 0;
143
144 static bool classof(const ABIInfo *info) {
145 return info->supportsSwift();
146 }
147 };
148} // end namespace CodeGen
149} // end namespace clang
150
151#endif
152