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/Attr.h"
13#include "clang/AST/CharUnits.h"
14#include "clang/AST/Type.h"
15#include "llvm/IR/CallingConv.h"
16#include "llvm/IR/Type.h"
17
18namespace llvm {
19class Value;
20class LLVMContext;
21class DataLayout;
22class Type;
23class FixedVectorType;
24} // namespace llvm
25
26namespace clang {
27class ASTContext;
28class CodeGenOptions;
29class FunctionDecl;
30class TargetInfo;
31
32namespace CodeGen {
33class ABIArgInfo;
34class Address;
35class CGCXXABI;
36class CGFunctionInfo;
37class CodeGenFunction;
38class CodeGenTypes;
39class RValue;
40class AggValueSlot;
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/// ABIInfo - Target specific hooks for defining how a type should be
48/// passed or returned from functions.
49class ABIInfo {
50protected:
51 CodeGen::CodeGenTypes &CGT;
52 llvm::CallingConv::ID RuntimeCC;
53
54public:
55 ABIInfo(CodeGen::CodeGenTypes &cgt)
56 : CGT(cgt), RuntimeCC(llvm::CallingConv::C) {}
57
58 virtual ~ABIInfo();
59
60 virtual bool allowBFloatArgsAndRet() const { return false; }
61
62 CodeGen::CGCXXABI &getCXXABI() const;
63 ASTContext &getContext() const;
64 llvm::LLVMContext &getVMContext() const;
65 const llvm::DataLayout &getDataLayout() const;
66 const TargetInfo &getTarget() const;
67 const CodeGenOptions &getCodeGenOpts() const;
68
69 /// Return the calling convention to use for system runtime
70 /// functions.
71 llvm::CallingConv::ID getRuntimeCC() const { return RuntimeCC; }
72
73 // Get X86ABIAVXLevel for the given FunctionDecl and ExtInfo.
74 // This can be different than the global / module level X86ABIAVXLevel
75 // due to function attributes.
76 virtual unsigned getX86ABIAVXLevel(const FunctionDecl *,
77 const FunctionType::ExtInfo &) const {
78 return 0;
79 }
80
81 virtual void computeInfo(CodeGen::CGFunctionInfo &FI) const = 0;
82
83 /// EmitVAArg - Emit the target dependent code to load a value of
84 /// \arg Ty from the va_list pointed to by \arg VAListAddr.
85
86 // FIXME: This is a gaping layering violation if we wanted to drop
87 // the ABI information any lower than CodeGen. Of course, for
88 // VAArg handling it has to be at this level; there is no way to
89 // abstract this out.
90 virtual RValue EmitVAArg(CodeGen::CodeGenFunction &CGF,
91 CodeGen::Address VAListAddr, QualType Ty,
92 AggValueSlot Slot) const = 0;
93
94 bool isAndroid() const;
95 bool isOHOSFamily() const;
96
97 /// Emit the target dependent code to load a value of
98 /// \arg Ty from the \c __builtin_ms_va_list pointed to by \arg VAListAddr.
99 virtual RValue EmitMSVAArg(CodeGen::CodeGenFunction &CGF,
100 CodeGen::Address VAListAddr, QualType Ty,
101 AggValueSlot Slot) const;
102
103 /// Emit the target dependent code to load a value of
104 /// \arg Ty from the \c __builtin_zos_va_list pointed to by \arg VAListAddr.
105 virtual RValue EmitZOSVAArg(CodeGen::CodeGenFunction &CGF,
106 CodeGen::Address VAListAddr, QualType Ty,
107 AggValueSlot Slot) const;
108
109 virtual bool isHomogeneousAggregateBaseType(QualType Ty) const;
110
111 virtual bool isHomogeneousAggregateSmallEnough(const Type *Base,
112 uint64_t Members) const;
113 virtual bool isZeroLengthBitfieldPermittedInHomogeneousAggregate() const;
114
115 /// isHomogeneousAggregate - Return true if a type is an ELFv2 homogeneous
116 /// aggregate. Base is set to the base element type, and Members is set
117 /// to the number of base elements.
118 bool isHomogeneousAggregate(QualType Ty, const Type *&Base,
119 uint64_t &Members) const;
120
121 // Implement the Type::IsPromotableIntegerType for ABI specific needs. The
122 // only difference is that this considers bit-precise integer types as well.
123 bool isPromotableIntegerTypeForABI(QualType Ty) const;
124
125 /// A convenience method to return an indirect ABIArgInfo with an
126 /// expected alignment equal to the ABI alignment of the given type.
127 CodeGen::ABIArgInfo
128 getNaturalAlignIndirect(QualType Ty, unsigned AddrSpace, bool ByVal = true,
129 bool Realign = false,
130 llvm::Type *Padding = nullptr) const;
131
132 CodeGen::ABIArgInfo getNaturalAlignIndirectInReg(QualType Ty,
133 bool Realign = false) const;
134
135 virtual void appendAttributeMangling(TargetAttr *Attr,
136 raw_ostream &Out) const;
137 virtual void appendAttributeMangling(TargetVersionAttr *Attr,
138 raw_ostream &Out) const;
139 virtual void appendAttributeMangling(TargetClonesAttr *Attr, unsigned Index,
140 raw_ostream &Out) const;
141 virtual void appendAttributeMangling(StringRef AttrStr,
142 raw_ostream &Out) const;
143
144 /// Returns the optimal vector memory type based on the given vector type. For
145 /// example, on certain targets, a vector with 3 elements might be promoted to
146 /// one with 4 elements to improve performance.
147 virtual llvm::FixedVectorType *
148 getOptimalVectorMemoryType(llvm::FixedVectorType *T,
149 const LangOptions &Opt) const;
150
151 virtual llvm::Value *createCoercedLoad(Address SrcAddr, const ABIArgInfo &AI,
152 CodeGenFunction &CGF) const;
153 virtual void createCoercedStore(llvm::Value *Val, Address DstAddr,
154 const ABIArgInfo &AI, bool DestIsVolatile,
155 CodeGenFunction &CGF) const;
156
157 /// Used by Arm64EC calling convention code to call into x86 calling
158 /// convention code for varargs function.
159 virtual ABIArgInfo classifyArgForArm64ECVarArg(QualType Ty) const;
160};
161
162/// Target specific hooks for defining how a type should be passed or returned
163/// from functions with one of the Swift calling conventions.
164class SwiftABIInfo {
165protected:
166 CodeGenTypes &CGT;
167 bool SwiftErrorInRegister;
168
169 bool occupiesMoreThan(ArrayRef<llvm::Type *> scalarTypes,
170 unsigned maxAllRegisters) const;
171
172public:
173 SwiftABIInfo(CodeGen::CodeGenTypes &CGT, bool SwiftErrorInRegister)
174 : CGT(CGT), SwiftErrorInRegister(SwiftErrorInRegister) {}
175
176 virtual ~SwiftABIInfo();
177
178 /// Returns true if an aggregate which expands to the given type sequence
179 /// should be passed / returned indirectly.
180 virtual bool shouldPassIndirectly(ArrayRef<llvm::Type *> ComponentTys,
181 bool AsReturnValue) const;
182
183 /// Returns true if the given vector type is legal from Swift's calling
184 /// convention perspective.
185 virtual bool isLegalVectorType(CharUnits VectorSize, llvm::Type *EltTy,
186 unsigned NumElts) const;
187
188 /// Returns true if swifterror is lowered to a register by the target ABI.
189 bool isSwiftErrorInRegister() const { return SwiftErrorInRegister; };
190};
191} // end namespace CodeGen
192} // end namespace clang
193
194#endif
195