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 boundries in dwarf
44 MCSymbol *PrevLabel = nullptr;
46 /// This location indicates end of function prologue and beginning of
48 DebugLoc PrologEndLoc;
50 /// If nonnull, stores the current machine instruction we're processing.
51 const MachineInstr *CurMI = nullptr;
53 LexicalScopes LScopes;
55 /// History of DBG_VALUE and clobber instructions for each user
56 /// variable. Variables are listed in order of appearance.
57 DbgValueHistoryMap DbgValues;
59 /// Maps instruction with label emitted before instruction.
60 /// FIXME: Make this private from DwarfDebug, we have the necessary accessors
62 DenseMap<const MachineInstr *, MCSymbol *> LabelsBeforeInsn;
64 /// Maps instruction with label emitted after instruction.
65 DenseMap<const MachineInstr *, MCSymbol *> LabelsAfterInsn;
67 /// Indentify instructions that are marking the beginning of or
68 /// ending of a scope.
69 void identifyScopeMarkers();
71 /// Ensure that a label will be emitted before MI.
72 void requestLabelBeforeInsn(const MachineInstr *MI) {
73 LabelsBeforeInsn.insert(std::make_pair(MI, nullptr));
76 /// Ensure that a label will be emitted after MI.
77 void requestLabelAfterInsn(const MachineInstr *MI) {
78 LabelsAfterInsn.insert(std::make_pair(MI, nullptr));
81 // AsmPrinterHandler overrides.
83 void beginInstruction(const MachineInstr *MI) override;
84 void endInstruction() override;
86 void beginFunction(const MachineFunction *MF) override;
87 void endFunction(const MachineFunction *MF) override;
89 /// Return Label preceding the instruction.
90 MCSymbol *getLabelBeforeInsn(const MachineInstr *MI);
92 /// Return Label immediately following the instruction.
93 MCSymbol *getLabelAfterInsn(const MachineInstr *MI);
95 /// Determine the relative position of the pieces described by P1 and P2.
96 /// Returns -1 if P1 is entirely before P2, 0 if P1 and P2 overlap,
97 /// 1 if P1 is entirely after P2.
98 static int pieceCmp(const DIExpression *P1, const DIExpression *P2);
100 /// Determine whether two variable pieces overlap.
101 static bool piecesOverlap(const DIExpression *P1, const DIExpression *P2);
103 /// If this type is derived from a base type then return base type size.
104 static uint64_t getBaseTypeSize(const DITypeRef TyRef);