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 /// Code generation optimization level.
54 enum class CodeGenOptLevel {
55 None = 0, ///< -O0
56 Less = 1, ///< -O1
57 Default = 2, ///< -O2, -Os
58 Aggressive = 3 ///< -O3
59 };
60
61 namespace CodeGenOpt {
62 /// Get the \c Level identified by the integer \p OL.
63 ///
64 /// Returns std::nullopt if \p OL is invalid.
65 inline std::optional<CodeGenOptLevel> getLevel(int OL) {
66 if (OL < 0 || OL > 3)
67 return std::nullopt;
68 return static_cast<CodeGenOptLevel>(OL);
69 }
70 /// Parse \p C as a single digit integer and get matching \c CodeGenLevel.
71 ///
72 /// Returns std::nullopt if the input is not a valid optimization level.
73 inline std::optional<CodeGenOptLevel> parseLevel(char C) {
74 if (C < '0')
75 return std::nullopt;
76 return getLevel(OL: static_cast<int>(C - '0'));
77 }
78 } // namespace CodeGenOpt
79
80 /// These enums are meant to be passed into addPassesToEmitFile to indicate
81 /// what type of file to emit, and returned by it to indicate what type of
82 /// file could actually be made.
83 enum class CodeGenFileType {
84 AssemblyFile,
85 ObjectFile,
86 Null // Do not emit any output.
87 };
88
89 // Specify what functions should keep the frame pointer.
90 enum class FramePointerKind { None, NonLeaf, All };
91
92 // Specify what type of zeroing callee-used registers.
93 namespace ZeroCallUsedRegs {
94 const unsigned ONLY_USED = 1U << 1;
95 const unsigned ONLY_GPR = 1U << 2;
96 const unsigned ONLY_ARG = 1U << 3;
97
98 enum class ZeroCallUsedRegsKind : unsigned int {
99 // Don't zero any call-used regs.
100 Skip = 1U << 0,
101 // Only zeros call-used GPRs used in the fn and pass args.
102 UsedGPRArg = ONLY_USED | ONLY_GPR | ONLY_ARG,
103 // Only zeros call-used GPRs used in the fn.
104 UsedGPR = ONLY_USED | ONLY_GPR,
105 // Only zeros call-used regs used in the fn and pass args.
106 UsedArg = ONLY_USED | ONLY_ARG,
107 // Only zeros call-used regs used in the fn.
108 Used = ONLY_USED,
109 // Zeros all call-used GPRs that pass args.
110 AllGPRArg = ONLY_GPR | ONLY_ARG,
111 // Zeros all call-used GPRs.
112 AllGPR = ONLY_GPR,
113 // Zeros all call-used regs that pass args.
114 AllArg = ONLY_ARG,
115 // Zeros all call-used regs.
116 All = 0,
117 };
118 } // namespace ZeroCallUsedRegs
119
120 enum class UWTableKind {
121 None = 0, ///< No unwind table requested
122 Sync = 1, ///< "Synchronous" unwind tables
123 Async = 2, ///< "Asynchronous" unwind tables (instr precise)
124 Default = 2,
125 };
126
127 enum class FunctionReturnThunksKind : unsigned int {
128 Keep = 0, ///< No function return thunk.
129 Extern = 1, ///< Replace returns with jump to thunk, don't emit thunk.
130 Invalid = 2, ///< Not used.
131 };
132
133 } // namespace llvm
134
135#endif
136

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