clang-tools  15.0.0git
CompileCommands.h
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1 //===--- CompileCommands.h - Manipulation of compile flags -------*- 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 #ifndef LLVM_CLANG_TOOLS_EXTRA_CLANGD_COMPILECOMMANDS_H
9 #define LLVM_CLANG_TOOLS_EXTRA_CLANGD_COMPILECOMMANDS_H
10 
11 #include "support/Threading.h"
12 #include "clang/Tooling/ArgumentsAdjusters.h"
13 #include "llvm/ADT/StringMap.h"
14 #include "llvm/ADT/StringRef.h"
15 #include <deque>
16 #include <string>
17 #include <vector>
18 
19 namespace clang {
20 namespace clangd {
21 
22 // CommandMangler transforms compile commands from some external source
23 // for use in clangd. This means:
24 // - running the frontend only, stripping args regarding output files etc
25 // - forcing the use of clangd's builtin headers rather than clang's
26 // - resolving argv0 as cc1 expects
27 // - injecting -isysroot flags on mac as the system clang does
29  // Absolute path to clang.
30  llvm::Optional<std::string> ClangPath;
31  // Directory containing builtin headers.
32  llvm::Optional<std::string> ResourceDir;
33  // Root for searching for standard library (passed to -isysroot).
34  llvm::Optional<std::string> Sysroot;
35 
36  // A command-mangler that doesn't know anything about the system.
37  // This is hermetic for unit-tests, but won't work well in production.
38  static CommandMangler forTests();
39  // Probe the system and build a command-mangler that knows the toolchain.
40  // - try to find clang on $PATH, otherwise fake a path near clangd
41  // - find the resource directory installed near clangd
42  // - on mac, find clang and isysroot by querying the `xcrun` launcher
43  static CommandMangler detect();
44 
45  void adjust(std::vector<std::string> &Cmd, llvm::StringRef File) const;
46  explicit operator clang::tooling::ArgumentsAdjuster() &&;
47 
48 private:
49  CommandMangler() = default;
50  Memoize<llvm::StringMap<std::string>> ResolvedDrivers;
51  Memoize<llvm::StringMap<std::string>> ResolvedDriversNoFollow;
52 };
53 
54 // Removes args from a command-line in a semantically-aware way.
55 //
56 // Internally this builds a large (0.5MB) table of clang options on first use.
57 // Both strip() and process() are fairly cheap after that.
58 //
59 // FIXME: this reimplements much of OptTable, it might be nice to expose more.
60 // The table-building strategy may not make sense outside clangd.
61 class ArgStripper {
62 public:
63  ArgStripper() = default;
64  ArgStripper(ArgStripper &&) = default;
65  ArgStripper(const ArgStripper &) = delete;
66  ArgStripper &operator=(ArgStripper &&) = default;
67  ArgStripper &operator=(const ArgStripper &) = delete;
68 
69  // Adds the arg to the set which should be removed.
70  //
71  // Recognized clang flags are stripped semantically. When "-I" is stripped:
72  // - so is its value (either as -Ifoo or -I foo)
73  // - aliases like --include-directory=foo are also stripped
74  // - CL-style /Ifoo will be removed if the args indicate MS-compatible mode
75  // Compile args not recognized as flags are removed literally, except:
76  // - strip("ABC*") will remove any arg with an ABC prefix.
77  //
78  // In either case, the -Xclang prefix will be dropped if present.
79  void strip(llvm::StringRef Arg);
80  // Remove the targets from a compile command, in-place.
81  void process(std::vector<std::string> &Args) const;
82 
83 private:
84  // Deletion rules, to be checked for each arg.
85  struct Rule {
86  llvm::StringRef Text; // Rule applies only if arg begins with Text.
87  unsigned char Modes = 0; // Rule applies only in specified driver modes.
88  uint16_t Priority = 0; // Lower is better.
89  uint16_t ExactArgs = 0; // Num args consumed when Arg == Text.
90  uint16_t PrefixArgs = 0; // Num args consumed when Arg starts with Text.
91  };
92  static llvm::ArrayRef<Rule> rulesFor(llvm::StringRef Arg);
93  const Rule *matchingRule(llvm::StringRef Arg, unsigned Mode,
94  unsigned &ArgCount) const;
95  llvm::SmallVector<Rule> Rules;
96  std::deque<std::string> Storage; // Store strings not found in option table.
97 };
98 
99 // Renders an argv list, with arguments separated by spaces.
100 // Where needed, arguments are "quoted" and escaped.
101 std::string printArgv(llvm::ArrayRef<llvm::StringRef> Args);
102 std::string printArgv(llvm::ArrayRef<std::string> Args);
103 
104 } // namespace clangd
105 } // namespace clang
106 
107 #endif
clang::clangd::printArgv
std::string printArgv(llvm::ArrayRef< llvm::StringRef > Args)
Definition: CompileCommands.cpp:628
clang::clangd::ArgStripper::strip
void strip(llvm::StringRef Arg)
Definition: CompileCommands.cpp:547
clang::clangd::ArgStripper::process
void process(std::vector< std::string > &Args) const
Definition: CompileCommands.cpp:587
Text
std::string Text
Definition: HTMLGenerator.cpp:80
clang::clangd::CommandMangler
Definition: CompileCommands.h:28
clang::clangd::CommandMangler::ResourceDir
llvm::Optional< std::string > ResourceDir
Definition: CompileCommands.h:32
clang::clangd::ArgStripper::ArgStripper
ArgStripper()=default
clang::clangd::CommandMangler::detect
static CommandMangler detect()
Definition: CompileCommands.cpp:188
clang::clangd::ArgStripper::operator=
ArgStripper & operator=(ArgStripper &&)=default
Args
llvm::json::Object Args
Definition: Trace.cpp:138
Threading.h
clang::clangd::CommandMangler::adjust
void adjust(std::vector< std::string > &Cmd, llvm::StringRef File) const
Definition: CompileCommands.cpp:198
clang::clangd::CommandMangler::Sysroot
llvm::Optional< std::string > Sysroot
Definition: CompileCommands.h:34
clang::clangd::ArgStripper
Definition: CompileCommands.h:61
clang::clangd::CommandMangler::ClangPath
llvm::Optional< std::string > ClangPath
Definition: CompileCommands.h:30
clang::clangd::Memoize
Memoize is a cache to store and reuse computation results based on a key.
Definition: Threading.h:146
clang
===– Representation.cpp - ClangDoc Representation --------—*- C++ -*-===//
Definition: ApplyReplacements.h:27
clang::clangd::CommandMangler::forTests
static CommandMangler forTests()
Definition: CompileCommands.cpp:196