hphp/runtime/vm/jit/unwind-itanium.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 #pragma once
  18
  19 #include "hphp/runtime/base/types.h"
  20 #include "hphp/runtime/base/rds.h"
  21 #include "hphp/runtime/base/typed-value.h"
  22 #include "hphp/runtime/ext/asio/ext_static-wait-handle.h"
  23
  24 #include "hphp/runtime/vm/jit/types.h"
  25
  26 #include "hphp/util/asm-x64.h"
  27 #include "hphp/util/either.h"
  28
  29 #include <cstddef>
  30
  31 #ifndef _MSC_VER
  32 #include <unwind.h>
  33 #else
  34 #include "hphp/util/unwind-itanium-msvc.h"
  35 #endif
  36
  37 namespace HPHP {
  38
  39 struct ActRec;
  40 struct EHFrameWriter;
  41
  42 namespace jit {
  43
  44 ///////////////////////////////////////////////////////////////////////////////
  45
  46 /*
  47  * Information the unwinder needs stored in RDS, and the rds::Link for it.
  48  * Used to pass values between unwinder code and catch traces.
  49  */
  50 struct UnwindRDS {
  51   /* PHP/C++ exception or Failed Static WaitHandle, nullptr if SetM exception */
  52   union {
  53     Either<ObjectData*, Exception*> exn;
  54     c_StaticWaitHandle* fswh;
  55   };
  56   TYPE_SCAN_CONSERVATIVE_FIELD(exn);
  57
  58   /* Some helpers need to signal an error along with a TypedValue to be pushed
  59    * on the eval stack. When present, that value lives here. */
  60   TypedValue tv;
  61
  62   /* This will be true iff the currently executing catch trace should side exit
  63    * to somewhere else in the TC, rather than resuming the unwind process. */
  64   bool doSideExit;
  65
  66   /* Indicates that we entered tc_unwind_resume directly rather than through
  67    * itanium ABI
  68    */
  69   bool sideEnter;
  70
  71   /* Indicates whether this is the first frame the unwinder will unwind
  72    */
  73   bool isFirstFrame;
  74
  75   /* The instruction pointer that async functions will use to return to
  76    */
  77   TCA savedRip;
  78 };
  79 extern rds::Link<UnwindRDS, rds::Mode::Normal> g_unwind_rds;
  80
  81 #define IMPLEMENT_OFF(Name, member)                             \
  82   inline ptrdiff_t unwinder##Name##Off() {                      \
  83     return g_unwind_rds.handle() + offsetof(UnwindRDS, member); \
  84   }
  85 IMPLEMENT_OFF(Exn, exn)
  86 IMPLEMENT_OFF(FSWH, fswh)
  87 IMPLEMENT_OFF(TV, tv)
  88 IMPLEMENT_OFF(SideExit, doSideExit)
  89 IMPLEMENT_OFF(SideEnter, sideEnter)
  90 IMPLEMENT_OFF(SavedRip, savedRip)
  91 #undef IMPLEMENT_OFF
  92
  93 ///////////////////////////////////////////////////////////////////////////////
  94
  95 /*
  96  * The personality routine for code emitted by the jit.
  97  */
  98 _Unwind_Reason_Code
  99 tc_unwind_personality(int version,
 100                       _Unwind_Action actions,
 101                       uint64_t exceptionClass,
 102                       _Unwind_Exception* exceptionObj,
 103                       _Unwind_Context* context);
 104
 105 using PersonalityFunc = _Unwind_Reason_Code(*)(int, _Unwind_Action, uint64_t,
 106                                                _Unwind_Exception*,
 107                                                _Unwind_Context*);
 108
 109 /*
 110  * Resume unwinding of jitted PHP frames.
 111  *
 112  * This is called from the endCatchHelper stub, which is hit at the end of
 113  * every catch trace.  It returns the new value of vmfp(), as well as the catch
 114  * trace to jump to---or nullptr if there is none, in which case the native
 115  * unwinder should be invoked via _Unwind_Resume().
 116  */
 117 struct TCUnwindInfo {
 118   TCA catchTrace;
 119   ActRec* fp;
 120 };
 121 TCUnwindInfo tc_unwind_resume(ActRec* fp, bool teardown);
 122 TCUnwindInfo tc_unwind_resume_stublogue(ActRec* fp, TCA savedRip);
 123
 124 /*
 125  * Called to initialize the unwinder and register an .eh_frame that covers the
 126  * TC.
 127  */
 128 void initUnwinder(TCA base, size_t size, PersonalityFunc fn);
 129
 130 ///////////////////////////////////////////////////////////////////////////////
 131
 132 }}
 133