xref: /llvm-project/flang/lib/Optimizer/Transforms/AddDebugInfo.cpp (revision 7740e933c41f07444ead12fd0417c5e53c6a4c1a)
1 //===-------------- AddDebugInfo.cpp -- add debug info -------------------===//
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 //===----------------------------------------------------------------------===//
10 /// \file
11 /// This pass populates some debug information for the module and functions.
12 //===----------------------------------------------------------------------===//
13 
14 #include "flang/Optimizer/Builder/FIRBuilder.h"
15 #include "flang/Optimizer/Builder/Todo.h"
16 #include "flang/Optimizer/Dialect/FIRDialect.h"
17 #include "flang/Optimizer/Dialect/FIROps.h"
18 #include "flang/Optimizer/Dialect/FIRType.h"
19 #include "flang/Optimizer/Dialect/Support/FIRContext.h"
20 #include "flang/Optimizer/Transforms/Passes.h"
21 #include "mlir/Dialect/Func/IR/FuncOps.h"
22 #include "mlir/Dialect/LLVMIR/LLVMDialect.h"
23 #include "mlir/IR/Matchers.h"
24 #include "mlir/IR/TypeUtilities.h"
25 #include "mlir/Pass/Pass.h"
26 #include "mlir/Transforms/DialectConversion.h"
27 #include "mlir/Transforms/GreedyPatternRewriteDriver.h"
28 #include "mlir/Transforms/RegionUtils.h"
29 #include "llvm/BinaryFormat/Dwarf.h"
30 #include "llvm/Support/Debug.h"
31 #include "llvm/Support/Path.h"
32 #include "llvm/Support/raw_ostream.h"
33 
34 namespace fir {
35 #define GEN_PASS_DEF_ADDDEBUGINFO
36 #define GEN_PASS_DECL_ADDDEBUGINFO
37 #include "flang/Optimizer/Transforms/Passes.h.inc"
38 } // namespace fir
39 
40 #define DEBUG_TYPE "flang-add-debug-foundation"
41 
42 namespace {
43 
44 class AddDebugInfoPass : public fir::impl::AddDebugInfoBase<AddDebugInfoPass> {
45 public:
46   void runOnOperation() override;
47 };
48 
49 } // namespace
50 
51 void AddDebugInfoPass::runOnOperation() {
52   mlir::ModuleOp module = getOperation();
53   mlir::MLIRContext *context = &getContext();
54   mlir::OpBuilder builder(context);
55   std::string inputFilePath("-");
56   if (auto fileLoc = module.getLoc().dyn_cast<mlir::FileLineColLoc>())
57     inputFilePath = fileLoc.getFilename().getValue();
58 
59   auto getFileAttr = [context](llvm::StringRef path) -> mlir::LLVM::DIFileAttr {
60     return mlir::LLVM::DIFileAttr::get(context, llvm::sys::path::filename(path),
61                                        llvm::sys::path::parent_path(path));
62   };
63 
64   mlir::LLVM::DIFileAttr fileAttr = getFileAttr(inputFilePath);
65   mlir::StringAttr producer = mlir::StringAttr::get(context, "Flang");
66   mlir::LLVM::DICompileUnitAttr cuAttr = mlir::LLVM::DICompileUnitAttr::get(
67       mlir::DistinctAttr::create(mlir::UnitAttr::get(context)),
68       llvm::dwarf::getLanguage("DW_LANG_Fortran95"), fileAttr, producer,
69       /*isOptimized=*/false, mlir::LLVM::DIEmissionKind::LineTablesOnly);
70 
71   module.walk([&](mlir::func::FuncOp funcOp) {
72     mlir::Location l = funcOp->getLoc();
73     // If fused location has already been created then nothing to do
74     // Otherwise, create a fused location.
75     if (l.dyn_cast<mlir::FusedLoc>())
76       return;
77 
78     llvm::StringRef funcFilePath;
79     if (l.dyn_cast<mlir::FileLineColLoc>())
80       funcFilePath =
81           l.dyn_cast<mlir::FileLineColLoc>().getFilename().getValue();
82     else
83       funcFilePath = inputFilePath;
84 
85     mlir::StringAttr funcName =
86         mlir::StringAttr::get(context, funcOp.getName());
87     mlir::LLVM::DIBasicTypeAttr bT = mlir::LLVM::DIBasicTypeAttr::get(
88         context, llvm::dwarf::DW_TAG_base_type, "void", /*sizeInBits=*/0,
89         /*encoding=*/1);
90     mlir::LLVM::DISubroutineTypeAttr subTypeAttr =
91         mlir::LLVM::DISubroutineTypeAttr::get(
92             context, llvm::dwarf::getCallingConvention("DW_CC_normal"),
93             {bT, bT});
94     mlir::LLVM::DIFileAttr funcFileAttr = getFileAttr(funcFilePath);
95 
96     // Only definitions need a distinct identifier and a compilation unit.
97     mlir::DistinctAttr id;
98     mlir::LLVM::DICompileUnitAttr compilationUnit;
99     auto subprogramFlags = mlir::LLVM::DISubprogramFlags::Optimized;
100     if (!funcOp.isExternal()) {
101       id = mlir::DistinctAttr::create(mlir::UnitAttr::get(context));
102       compilationUnit = cuAttr;
103       subprogramFlags =
104           subprogramFlags | mlir::LLVM::DISubprogramFlags::Definition;
105     }
106     auto spAttr = mlir::LLVM::DISubprogramAttr::get(
107         context, id, compilationUnit, fileAttr, funcName, funcName,
108         funcFileAttr,
109         /*line=*/1,
110         /*scopeline=*/1, subprogramFlags, subTypeAttr);
111     funcOp->setLoc(builder.getFusedLoc({funcOp->getLoc()}, spAttr));
112   });
113 }
114 
115 std::unique_ptr<mlir::Pass> fir::createAddDebugInfoPass() {
116   return std::make_unique<AddDebugInfoPass>();
117 }
118