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
37 // FIXME: All of this stuff should be part of the target interface
38 // somehow. It is currently here because it is not clear how to factor
39 // the targets to support this, since the Targets currently live in a
40 // layer below types n'stuff.
41
42
43 /// ABIInfo - Target specific hooks for defining how a type should be
44 /// passed or returned from functions.
45 class ABIInfo {
46 protected:
47 CodeGen::CodeGenTypes &CGT;
48 llvm::CallingConv::ID RuntimeCC;
49 public:
50 ABIInfo(CodeGen::CodeGenTypes &cgt)
51 : CGT(cgt), RuntimeCC(llvm::CallingConv::C) {}
52
53 virtual ~ABIInfo();
54
55 virtual bool allowBFloatArgsAndRet() const { return false; }
56
57 CodeGen::CGCXXABI &getCXXABI() const;
58 ASTContext &getContext() const;
59 llvm::LLVMContext &getVMContext() const;
60 const llvm::DataLayout &getDataLayout() const;
61 const TargetInfo &getTarget() const;
62 const CodeGenOptions &getCodeGenOpts() const;
63
64 /// Return the calling convention to use for system runtime
65 /// functions.
66 llvm::CallingConv::ID getRuntimeCC() const {
67 return RuntimeCC;
68 }
69
70 virtual void computeInfo(CodeGen::CGFunctionInfo &FI) const = 0;
71
72 /// EmitVAArg - Emit the target dependent code to load a value of
73 /// \arg Ty from the va_list pointed to by \arg VAListAddr.
74
75 // FIXME: This is a gaping layering violation if we wanted to drop
76 // the ABI information any lower than CodeGen. Of course, for
77 // VAArg handling it has to be at this level; there is no way to
78 // abstract this out.
79 virtual CodeGen::Address EmitVAArg(CodeGen::CodeGenFunction &CGF,
80 CodeGen::Address VAListAddr,
81 QualType Ty) const = 0;
82
83 bool isAndroid() const;
84
85 /// Emit the target dependent code to load a value of
86 /// \arg Ty from the \c __builtin_ms_va_list pointed to by \arg VAListAddr.
87 virtual CodeGen::Address EmitMSVAArg(CodeGen::CodeGenFunction &CGF,
88 CodeGen::Address VAListAddr,
89 QualType Ty) const;
90
91 virtual bool isHomogeneousAggregateBaseType(QualType Ty) const;
92
93 virtual bool isHomogeneousAggregateSmallEnough(const Type *Base,
94 uint64_t Members) const;
95 virtual bool isZeroLengthBitfieldPermittedInHomogeneousAggregate() const;
96
97 bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
98 uint64_t &Members) const;
99
100 // Implement the Type::IsPromotableIntegerType for ABI specific needs. The
101 // only difference is that this considers bit-precise integer types as well.
102 bool isPromotableIntegerTypeForABI(QualType Ty) const;
103
104 /// A convenience method to return an indirect ABIArgInfo with an
105 /// expected alignment equal to the ABI alignment of the given type.
106 CodeGen::ABIArgInfo
107 getNaturalAlignIndirect(QualType Ty, bool ByVal = true,
108 bool Realign = false,
109 llvm::Type *Padding = nullptr) const;
110
111 CodeGen::ABIArgInfo
112 getNaturalAlignIndirectInReg(QualType Ty, bool Realign = false) const;
113 };
114
115 /// Target specific hooks for defining how a type should be passed or returned
116 /// from functions with one of the Swift calling conventions.
117 class SwiftABIInfo {
118 protected:
119 CodeGenTypes &CGT;
120 bool SwiftErrorInRegister;
121
122 public:
123 SwiftABIInfo(CodeGen::CodeGenTypes &CGT, bool SwiftErrorInRegister)
124 : CGT(CGT), SwiftErrorInRegister(SwiftErrorInRegister) {}
125
126 virtual ~SwiftABIInfo();
127
128 /// Returns true if an aggregate which expands to the given type sequence
129 /// should be passed / returned indirectly.
130 virtual bool shouldPassIndirectly(ArrayRef<llvm::Type *> ComponentTys,
131 bool AsReturnValue) const;
132
133 /// Returns true if the given vector type is legal from Swift's calling
134 /// convention perspective.
135 virtual bool isLegalVectorType(CharUnits VectorSize, llvm::Type *EltTy,
136 unsigned NumElts) const;
137
138 /// Returns true if swifterror is lowered to a register by the target ABI.
139 bool isSwiftErrorInRegister() const { return SwiftErrorInRegister; };
140 };
141} // end namespace CodeGen
142} // end namespace clang
143
144#endif
145

source code of clang/lib/CodeGen/ABIInfo.h