1//===- mlir-src-sharder.cpp - A tool for sharder generated source files ---===//
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#include "mlir/Support/FileUtilities.h"
10#include "mlir/Support/LLVM.h"
11#include "llvm/Support/CommandLine.h"
12#include "llvm/Support/InitLLVM.h"
13#include "llvm/Support/MemoryBuffer.h"
14#include "llvm/Support/ToolOutputFile.h"
15
16using namespace mlir;
17
18/// Create a dependency file for `-d` option.
19///
20/// This functionality is generally only for the benefit of the build system,
21/// and is modeled after the same option in TableGen.
22static LogicalResult createDependencyFile(StringRef outputFilename,
23 StringRef dependencyFile) {
24 if (outputFilename == "-") {
25 llvm::errs() << "error: the option -d must be used together with -o\n";
26 return failure();
27 }
28
29 std::string errorMessage;
30 std::unique_ptr<llvm::ToolOutputFile> outputFile =
31 openOutputFile(outputFilename: dependencyFile, errorMessage: &errorMessage);
32 if (!outputFile) {
33 llvm::errs() << errorMessage << "\n";
34 return failure();
35 }
36
37 outputFile->os() << outputFilename << ":\n";
38 outputFile->keep();
39 return success();
40}
41
42int main(int argc, char **argv) {
43 // FIXME: This is necessary because we link in TableGen, which defines its
44 // options as static variables.. some of which overlap with our options.
45 llvm::cl::ResetCommandLineParser();
46
47 llvm::cl::opt<unsigned> opShardIndex(
48 "op-shard-index", llvm::cl::desc("The current shard index"));
49 llvm::cl::opt<std::string> inputFilename(llvm::cl::Positional,
50 llvm::cl::desc("<input file>"),
51 llvm::cl::init(Val: "-"));
52 llvm::cl::opt<std::string> outputFilename(
53 "o", llvm::cl::desc("Output filename"), llvm::cl::value_desc("filename"),
54 llvm::cl::init(Val: "-"));
55 llvm::cl::list<std::string> includeDirs(
56 "I", llvm::cl::desc("Directory of include files"),
57 llvm::cl::value_desc("directory"), llvm::cl::Prefix);
58 llvm::cl::opt<std::string> dependencyFilename(
59 "d", llvm::cl::desc("Dependency filename"),
60 llvm::cl::value_desc("filename"), llvm::cl::init(Val: ""));
61 llvm::cl::opt<bool> writeIfChanged(
62 "write-if-changed",
63 llvm::cl::desc("Only write to the output file if it changed"));
64
65 // `ResetCommandLineParser` at the above unregistered the "D" option
66 // of `llvm-tblgen`, which caused `TestOps.cpp` to fail due to
67 // "Unknnown command line argument '-D...`" when a macros name is
68 // present. The following is a workaround to re-register it again.
69 llvm::cl::list<std::string> macroNames(
70 "D",
71 llvm::cl::desc(
72 "Name of the macro to be defined -- ignored by mlir-src-sharder"),
73 llvm::cl::value_desc("macro name"), llvm::cl::Prefix);
74
75 llvm::InitLLVM y(argc, argv);
76 llvm::cl::ParseCommandLineOptions(argc, argv);
77
78 // Open the input file.
79 std::string errorMessage;
80 std::unique_ptr<llvm::MemoryBuffer> inputFile =
81 openInputFile(inputFilename, errorMessage: &errorMessage);
82 if (!inputFile) {
83 llvm::errs() << errorMessage << "\n";
84 return 1;
85 }
86
87 // Write the output to a buffer.
88 std::string outputStr;
89 llvm::raw_string_ostream os(outputStr);
90 os << "#define GET_OP_DEFS_" << opShardIndex << "\n"
91 << inputFile->getBuffer();
92
93 // Determine whether we need to write the output file.
94 bool shouldWriteOutput = true;
95 if (writeIfChanged) {
96 // Only update the real output file if there are any differences. This
97 // prevents recompilation of all the files depending on it if there aren't
98 // any.
99 if (auto existingOrErr =
100 llvm::MemoryBuffer::getFile(Filename: outputFilename, /*IsText=*/true))
101 if (std::move(existingOrErr.get())->getBuffer() == outputStr)
102 shouldWriteOutput = false;
103 }
104
105 // Populate the output file if necessary.
106 if (shouldWriteOutput) {
107 std::unique_ptr<llvm::ToolOutputFile> outputFile =
108 openOutputFile(outputFilename, errorMessage: &errorMessage);
109 if (!outputFile) {
110 llvm::errs() << errorMessage << "\n";
111 return 1;
112 }
113 outputFile->os() << os.str();
114 outputFile->keep();
115 }
116
117 // Always write the depfile, even if the main output hasn't changed. If it's
118 // missing, Ninja considers the output dirty.
119 if (!dependencyFilename.empty())
120 if (failed(Result: createDependencyFile(outputFilename, dependencyFile: dependencyFilename)))
121 return 1;
122
123 return 0;
124}
125

source code of mlir/tools/mlir-src-sharder/mlir-src-sharder.cpp