hphp/runtime/vm/debug/dwarf.h

   1 /*
   2    +----------------------------------------------------------------------+
   3    | HipHop for PHP                                                       |
   4    +----------------------------------------------------------------------+
   5    | Copyright (c) 2010-present Facebook, Inc. (http://www.facebook.com)  |
   6    +----------------------------------------------------------------------+
   7    | This source file is subject to version 3.01 of the PHP license,      |
   8    | that is bundled with this package in the file LICENSE, and is        |
   9    | available through the world-wide-web at the following url:           |
  10    | http://www.php.net/license/3_01.txt                                  |
  11    | If you did not receive a copy of the PHP license and are unable to   |
  12    | obtain it through the world-wide-web, please send a note to          |
  13    | license@php.net so we can mail you a copy immediately.               |
  14    +----------------------------------------------------------------------+
  15 */
  16
  17 #ifndef HPHP_DWARF_H_
  18 #define HPHP_DWARF_H_
  19
  20 #include "hphp/runtime/vm/jit/translator.h"
  21 #include "hphp/util/eh-frame.h"
  22
  23 #include <folly/Optional.h>
  24
  25 #include <string>
  26 #include <vector>
  27
  28 namespace HPHP { namespace Debug {
  29
  30 using jit::TCA;
  31
  32 typedef enum {
  33   RAX,
  34   RDX,
  35   RCX,
  36   RBX,
  37   RSI,
  38   RDI,
  39   RBP,
  40   RSP,
  41   R8,
  42   R9,
  43   R10,
  44   R11,
  45   R12,
  46   R13,
  47   R14,
  48   R15,
  49   RIP
  50 } x86_64_regnum_t;
  51
  52 const int DWARF_CODE_ALIGN = 1;
  53 const int DWARF_DATA_ALIGN = 8;
  54
  55 #if (defined(FACEBOOK) || defined(LIBDWARF_CONST_NAME))
  56 #define LIBDWARF_CALLBACK_NAME_TYPE const char*
  57 #else
  58 #define LIBDWARF_CALLBACK_NAME_TYPE char*
  59 #endif
  60
  61 extern int g_dwarfCallback(
  62   LIBDWARF_CALLBACK_NAME_TYPE name, int size, Dwarf_Unsigned type,
  63   Dwarf_Unsigned flags, Dwarf_Unsigned link, Dwarf_Unsigned info,
  64   Dwarf_Unsigned *sect_name_index, Dwarf_Ptr handle, int *error);
  65
  66 struct TCRange {
  67   TCRange() : m_start(nullptr), m_end(nullptr), m_isAcold(false) {
  68     assert(!isValid());
  69   }
  70   TCRange(const TCA start, const TCA end, bool isAcold) :
  71     m_start(start), m_end(end), m_isAcold(isAcold) { V(); }
  72
  73   TCRange& operator=(const TCRange& r) {
  74     m_start = r.m_start;
  75     m_end = r.m_end;
  76     m_isAcold = r.m_isAcold;
  77     V();
  78     return *this;
  79   }
  80
  81   bool isValid() const {
  82     assert(bool(m_start) == bool(m_end));
  83     assert(!m_start || m_start < m_end);
  84     assert(!m_start || (m_end - m_start) < (1ll << 32));
  85     return bool(m_start);
  86   }
  87   bool isAcold() const { return m_isAcold; }
  88   TCA begin() const { V(); return m_start; }
  89   TCA end() const   { V(); return m_end; };
  90   uint32_t size() const   { V(); return m_end - m_start; }
  91
  92   void extend(const TCA newEnd) {
  93     assert(newEnd >= m_end);
  94     m_end = newEnd;
  95     V();
  96   }
  97
  98 private:
  99   void V() const { assert(isValid()); }
 100
 101 private:
 102   TCA m_start, m_end;
 103   bool m_isAcold;
 104 };
 105
 106 struct DwarfBuf {
 107   void byte(uint8_t c);
 108
 109   void clear();
 110   int size();
 111   uint8_t *getBuf();
 112   void print();
 113
 114   void dwarf_cfa_def_cfa(uint8_t reg, uint8_t offset);
 115   void dwarf_cfa_same_value(uint8_t reg);
 116   void dwarf_cfa_offset_extended_sf(uint8_t reg, int8_t offset);
 117
 118 private:
 119   std::vector<uint8_t> m_buf;
 120 };
 121
 122 struct LineEntry {
 123   TCRange range;
 124   int lineNumber;
 125   LineEntry(TCRange r, int l) : range(r), lineNumber(l) {}
 126 };
 127
 128 struct DwarfChunk;
 129
 130 struct FunctionInfo {
 131   std::string name;
 132   const char *file;
 133   TCRange range;
 134   bool exit;
 135   bool m_perfSynced;
 136   std::vector<LineEntry> m_lineTable;
 137   std::vector<std::string> m_namedLocals;
 138   DwarfChunk* m_chunk;
 139   FunctionInfo() : m_chunk(nullptr) { }
 140   FunctionInfo(TCRange r, bool ex)
 141     : range(r), exit(ex), m_perfSynced(false),
 142     m_namedLocals(std::vector<std::string>()), m_chunk(nullptr) {}
 143   void setPerfSynced() { m_perfSynced = true; }
 144   void clearPerfSynced() { m_perfSynced = false; }
 145   bool perfSynced() const { return m_perfSynced; }
 146 };
 147
 148 struct DwarfChunk {
 149   DwarfBuf m_buf;
 150   std::vector<FunctionInfo *> m_functions;
 151   char *m_symfile;
 152   bool m_synced;
 153   DwarfChunk() : m_symfile(nullptr), m_synced(false) {}
 154   void setSynced() { m_synced = true; }
 155   void clearSynced() { m_synced = false; }
 156   bool isSynced() const { return m_synced; }
 157 };
 158
 159 typedef std::map<TCA, FunctionInfo* > FuncDB;
 160 typedef std::vector<FunctionInfo* > FuncPtrDB;
 161
 162 struct DwarfInfo {
 163   typedef std::map<TCA, jit::TransRec> TransDB;
 164
 165   std::vector<DwarfChunk*> m_dwarfChunks;
 166   /* Array of chunks indexed by lg(#functions in chunk) + 1.
 167    * i.e. m_dwarfChunk[i] = pointer to chunk with
 168    * 2^(i-1) * RuntimeOption::EvalGdbSyncChunks functions, or NULL if
 169    * there is no such chunk. The first chunk m_dwarfChunks[0] is special in
 170    * that it can be partially full. All other chunks are completely full.
 171    */
 172   FuncDB m_functions;
 173
 174   const char *lookupFile(const Unit *unit);
 175   void addLineEntries(TCRange range, const Unit *unit,
 176                       PC instr, FunctionInfo* f);
 177   void transferFuncs(DwarfChunk* from, DwarfChunk* to);
 178   void compactChunks();
 179   DwarfChunk* addTracelet(TCRange range,
 180                           folly::Optional<std::string> name,
 181                           const Func* func,
 182                           PC instr,
 183                           bool exit,
 184                           bool inPrologue);
 185   void syncChunks();
 186 };
 187
 188 }}
 189
 190 #endif