1//===-- llvm/Support/CodeGen.h - CodeGen Concepts ---------------*- 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 file define some types which define code generation concepts. For
10// example, relocation model.
11//
12//===----------------------------------------------------------------------===//
13
14#ifndef LLVM_SUPPORT_CODEGEN_H
15#define LLVM_SUPPORT_CODEGEN_H
16
17#include <cstdint>
18#include <optional>
19
20namespace llvm {
21
22 // Relocation model types.
23 namespace Reloc {
24 // Cannot be named PIC due to collision with -DPIC
25 enum Model { Static, PIC_, DynamicNoPIC, ROPI, RWPI, ROPI_RWPI };
26 }
27
28 // Code model types.
29 namespace CodeModel {
30 // Sync changes with CodeGenCWrappers.h.
31 enum Model { Tiny, Small, Kernel, Medium, Large };
32 }
33
34 namespace PICLevel {
35 // This is used to map -fpic/-fPIC.
36 enum Level { NotPIC=0, SmallPIC=1, BigPIC=2 };
37 }
38
39 namespace PIELevel {
40 enum Level { Default=0, Small=1, Large=2 };
41 }
42
43 // TLS models.
44 namespace TLSModel {
45 enum Model {
46 GeneralDynamic,
47 LocalDynamic,
48 InitialExec,
49 LocalExec
50 };
51 }
52
53 namespace CodeGenOpt {
54 /// Type for the unique integer IDs of code generation optimization levels.
55 using IDType = int;
56 /// Code generation optimization level.
57 enum Level : IDType {
58 None = 0, ///< -O0
59 Less = 1, ///< -O1
60 Default = 2, ///< -O2, -Os
61 Aggressive = 3 ///< -O3
62 };
63 /// Get the \c Level identified by the integer \p ID.
64 ///
65 /// Returns std::nullopt if \p ID is invalid.
66 inline std::optional<Level> getLevel(IDType ID) {
67 if (ID < 0 || ID > 3)
68 return std::nullopt;
69 return static_cast<Level>(ID);
70 }
71 /// Parse \p C as a single digit integer ID and get matching \c Level.
72 ///
73 /// Returns std::nullopt if the input is not a valid digit or not a valid ID.
74 inline std::optional<Level> parseLevel(char C) {
75 if (C < '0')
76 return std::nullopt;
77 return getLevel(ID: static_cast<IDType>(C - '0'));
78 }
79 } // namespace CodeGenOpt
80
81 /// These enums are meant to be passed into addPassesToEmitFile to indicate
82 /// what type of file to emit, and returned by it to indicate what type of
83 /// file could actually be made.
84 enum CodeGenFileType {
85 CGFT_AssemblyFile,
86 CGFT_ObjectFile,
87 CGFT_Null // Do not emit any output.
88 };
89
90 // Specify what functions should keep the frame pointer.
91 enum class FramePointerKind { None, NonLeaf, All };
92
93 // Specify what type of zeroing callee-used registers.
94 namespace ZeroCallUsedRegs {
95 const unsigned ONLY_USED = 1U << 1;
96 const unsigned ONLY_GPR = 1U << 2;
97 const unsigned ONLY_ARG = 1U << 3;
98
99 enum class ZeroCallUsedRegsKind : unsigned int {
100 // Don't zero any call-used regs.
101 Skip = 1U << 0,
102 // Only zeros call-used GPRs used in the fn and pass args.
103 UsedGPRArg = ONLY_USED | ONLY_GPR | ONLY_ARG,
104 // Only zeros call-used GPRs used in the fn.
105 UsedGPR = ONLY_USED | ONLY_GPR,
106 // Only zeros call-used regs used in the fn and pass args.
107 UsedArg = ONLY_USED | ONLY_ARG,
108 // Only zeros call-used regs used in the fn.
109 Used = ONLY_USED,
110 // Zeros all call-used GPRs that pass args.
111 AllGPRArg = ONLY_GPR | ONLY_ARG,
112 // Zeros all call-used GPRs.
113 AllGPR = ONLY_GPR,
114 // Zeros all call-used regs that pass args.
115 AllArg = ONLY_ARG,
116 // Zeros all call-used regs.
117 All = 0,
118 };
119 } // namespace ZeroCallUsedRegs
120
121 enum class UWTableKind {
122 None = 0, ///< No unwind table requested
123 Sync = 1, ///< "Synchronous" unwind tables
124 Async = 2, ///< "Asynchronous" unwind tables (instr precise)
125 Default = 2,
126 };
127
128 enum class FunctionReturnThunksKind : unsigned int {
129 Keep = 0, ///< No function return thunk.
130 Extern = 1, ///< Replace returns with jump to thunk, don't emit thunk.
131 Invalid = 2, ///< Not used.
132 };
133
134 } // namespace llvm
135
136#endif
137

source code of include/llvm-17/llvm/Support/CodeGen.h