1 //===- Main.cpp - Top-Level TableGen implementation -----------------------===//
2 //
3 // The LLVM Compiler Infrastructure
4 //
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
7 //
8 //===----------------------------------------------------------------------===//
9 //
10 // TableGen is a tool which can be used to build up a description of something,
11 // then invoke one or more "tablegen backends" to emit information about the
12 // description in some predefined format. In practice, this is used by the LLVM
13 // code generators to automate generation of a code generator through a
14 // high-level description of the target.
15 //
16 //===----------------------------------------------------------------------===//
17
18 #include "llvm/TableGen/Main.h"
19 #include "TGParser.h"
20 #include "llvm/Support/CommandLine.h"
21 #include "llvm/Support/FileSystem.h"
22 #include "llvm/Support/MemoryBuffer.h"
23 #include "llvm/Support/ToolOutputFile.h"
24 #include "llvm/TableGen/Error.h"
25 #include "llvm/TableGen/Record.h"
26 #include <algorithm>
27 #include <cstdio>
28 #include <system_error>
29 using namespace llvm;
30
31 static cl::opt<std::string>
32 OutputFilename("o", cl::desc("Output filename"), cl::value_desc("filename"),
33 cl::init("-"));
34
35 static cl::opt<std::string>
36 DependFilename("d",
37 cl::desc("Dependency filename"),
38 cl::value_desc("filename"),
39 cl::init(""));
40
41 static cl::opt<std::string>
42 InputFilename(cl::Positional, cl::desc("<input file>"), cl::init("-"));
43
44 static cl::list<std::string>
45 IncludeDirs("I", cl::desc("Directory of include files"),
46 cl::value_desc("directory"), cl::Prefix);
47
48 /// \brief Create a dependency file for `-d` option.
49 ///
50 /// This functionality is really only for the benefit of the build system.
51 /// It is similar to GCC's `-M*` family of options.
createDependencyFile(const TGParser & Parser,const char * argv0)52 static int createDependencyFile(const TGParser &Parser, const char *argv0) {
53 if (OutputFilename == "-") {
54 errs() << argv0 << ": the option -d must be used together with -o\n";
55 return 1;
56 }
57 std::error_code EC;
58 tool_output_file DepOut(DependFilename, EC, sys::fs::F_Text);
59 if (EC) {
60 errs() << argv0 << ": error opening " << DependFilename << ":"
61 << EC.message() << "\n";
62 return 1;
63 }
64 DepOut.os() << OutputFilename << ":";
65 for (const auto &Dep : Parser.getDependencies()) {
66 DepOut.os() << ' ' << Dep.first;
67 }
68 DepOut.os() << "\n";
69 DepOut.keep();
70 return 0;
71 }
72
TableGenMain(char * argv0,TableGenMainFn * MainFn)73 int llvm::TableGenMain(char *argv0, TableGenMainFn *MainFn) {
74 RecordKeeper Records;
75
76 // Parse the input file.
77 ErrorOr<std::unique_ptr<MemoryBuffer>> FileOrErr =
78 MemoryBuffer::getFileOrSTDIN(InputFilename);
79 if (std::error_code EC = FileOrErr.getError()) {
80 errs() << "Could not open input file '" << InputFilename
81 << "': " << EC.message() << "\n";
82 return 1;
83 }
84
85 // Tell SrcMgr about this buffer, which is what TGParser will pick up.
86 SrcMgr.AddNewSourceBuffer(std::move(*FileOrErr), SMLoc());
87
88 // Record the location of the include directory so that the lexer can find
89 // it later.
90 SrcMgr.setIncludeDirs(IncludeDirs);
91
92 TGParser Parser(SrcMgr, Records);
93
94 if (Parser.ParseFile())
95 return 1;
96
97 std::error_code EC;
98 tool_output_file Out(OutputFilename, EC, sys::fs::F_Text);
99 if (EC) {
100 errs() << argv0 << ": error opening " << OutputFilename << ":"
101 << EC.message() << "\n";
102 return 1;
103 }
104 if (!DependFilename.empty()) {
105 if (int Ret = createDependencyFile(Parser, argv0))
106 return Ret;
107 }
108
109 if (MainFn(Out.os(), Records))
110 return 1;
111
112 if (ErrorsPrinted > 0) {
113 errs() << argv0 << ": " << ErrorsPrinted << " errors.\n";
114 return 1;
115 }
116
117 // Declare success.
118 Out.keep();
119 return 0;
120 }
121