1 //===-- llvm/lib/CodeGen/AsmPrinter/DebugHandlerBase.h --------*- C++ -*--===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // Common functionality for different debug information format backends.
11 // LLVM currently supports DWARF and CodeView.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_LIB_CODEGEN_ASMPRINTER_DEBUGHANDLERBASE_H
16 #define LLVM_LIB_CODEGEN_ASMPRINTER_DEBUGHANDLERBASE_H
18 #include "AsmPrinterHandler.h"
19 #include "DbgValueHistoryCalculator.h"
20 #include "llvm/CodeGen/LexicalScopes.h"
21 #include "llvm/CodeGen/MachineInstr.h"
26 class MachineModuleInfo;
28 /// Base class for debug information backends. Common functionality related to
29 /// tracking which variables and scopes are alive at a given PC live here.
30 class DebugHandlerBase : public AsmPrinterHandler {
32 DebugHandlerBase(AsmPrinter *A);
34 /// Target of debug info emission.
37 /// Collected machine module information.
38 MachineModuleInfo *MMI;
40 /// Previous instruction's location information. This is used to
41 /// determine label location to indicate scope boundaries in debug info.
42 /// We track the previous instruction's source location (if not line 0),
43 /// whether it was a label, and its parent BB.
45 MCSymbol *PrevLabel = nullptr;
46 const MachineBasicBlock *PrevInstBB = nullptr;
48 /// This location indicates end of function prologue and beginning of
50 DebugLoc PrologEndLoc;
52 /// If nonnull, stores the current machine instruction we're processing.
53 const MachineInstr *CurMI = nullptr;
55 LexicalScopes LScopes;
57 /// History of DBG_VALUE and clobber instructions for each user
58 /// variable. Variables are listed in order of appearance.
59 DbgValueHistoryMap DbgValues;
61 /// Maps instruction with label emitted before instruction.
62 /// FIXME: Make this private from DwarfDebug, we have the necessary accessors
64 DenseMap<const MachineInstr *, MCSymbol *> LabelsBeforeInsn;
66 /// Maps instruction with label emitted after instruction.
67 DenseMap<const MachineInstr *, MCSymbol *> LabelsAfterInsn;
69 /// Indentify instructions that are marking the beginning of or
70 /// ending of a scope.
71 void identifyScopeMarkers();
73 /// Ensure that a label will be emitted before MI.
74 void requestLabelBeforeInsn(const MachineInstr *MI) {
75 LabelsBeforeInsn.insert(std::make_pair(MI, nullptr));
78 /// Ensure that a label will be emitted after MI.
79 void requestLabelAfterInsn(const MachineInstr *MI) {
80 LabelsAfterInsn.insert(std::make_pair(MI, nullptr));
83 // AsmPrinterHandler overrides.
85 void beginInstruction(const MachineInstr *MI) override;
86 void endInstruction() override;
88 void beginFunction(const MachineFunction *MF) override;
89 void endFunction(const MachineFunction *MF) override;
91 /// Return Label preceding the instruction.
92 MCSymbol *getLabelBeforeInsn(const MachineInstr *MI);
94 /// Return Label immediately following the instruction.
95 MCSymbol *getLabelAfterInsn(const MachineInstr *MI);
97 /// Determine the relative position of the fragments described by P1 and P2.
98 /// Returns -1 if P1 is entirely before P2, 0 if P1 and P2 overlap, 1 if P1 is
99 /// entirely after P2.
100 static int fragmentCmp(const DIExpression *P1, const DIExpression *P2);
102 /// Determine whether two variable fragments overlap.
103 static bool fragmentsOverlap(const DIExpression *P1, const DIExpression *P2);
105 /// If this type is derived from a base type then return base type size.
106 static uint64_t getBaseTypeSize(const DITypeRef TyRef);