Track prologue offset of Code and use for more precise return addresses

runtime/vm/object.cc

 // Copyright (c) 2012, the Dart project authors.  Please see the AUTHORS file
 // for details. All rights reserved. Use of this source code is governed by a
 // BSD-style license that can be found in the LICENSE file.
 
 #include "vm/object.h"
 
 #include "include/dart_api.h"
 #include "platform/assert.h"
 #include "vm/assembler.h"
 #include "vm/cpu.h"
@@ skipping 12252 matching lines @@
   return *comments;
 }
 
 
 void Code::set_comments(const Code::Comments& comments) const {
   ASSERT(comments.comments_.IsOld());
   StorePointer(&raw_ptr()->comments_, comments.comments_.raw());
 }
 
 
-void Code::set_inlined_intervals(const Array& value) const {
-  ASSERT(value.IsOld());
-  StorePointer(&raw_ptr()->inlined_intervals_, value.raw());
+void Code::SetPrologueOffset(intptr_t offset) const {
+  ASSERT(offset >= 0);
+  StoreSmi(
+      reinterpret_cast<RawSmi* const *>(&raw_ptr()->return_address_metadata_),
+      Smi::New(offset));
 }
 
 
-void Code::set_inlined_id_to_function(const Array& value) const {
-  ASSERT(value.IsOld());
-  StorePointer(&raw_ptr()->inlined_id_to_function_, value.raw());
+intptr_t Code::GetPrologueOffset() const {
+  const Object& object = Object::Handle(raw_ptr()->return_address_metadata_);
+  // In the future we may put something other than a smi in
+  // |return_address_metadata_|.
+  if (object.IsNull() || !object.IsSmi()) {
+    return -1;
+  }
+  return Smi::Cast(object).Value();
 }
 
 
+RawArray* Code::GetInlinedIntervals() const {
+  const Array& metadata = Array::Handle(raw_ptr()->inlined_metadata_);
+  if (metadata.IsNull()) {
+    return metadata.raw();
+  }
+  return reinterpret_cast<RawArray*>(
+      metadata.At(RawCode::kInlinedIntervalsIndex));
+}
+
+
+void Code::SetInlinedIntervals(const Array& value) const {
+  if (raw_ptr()->inlined_metadata_ == Array::null()) {
+    StorePointer(&raw_ptr()->inlined_metadata_,
+                 Array::New(RawCode::kInlinedMetadataSize, Heap::kOld));
+  }
+  const Array& metadata = Array::Handle(raw_ptr()->inlined_metadata_);
+  ASSERT(!metadata.IsNull());
+  ASSERT(metadata.IsOld());
+  ASSERT(value.IsOld());
+  metadata.SetAt(RawCode::kInlinedIntervalsIndex, value);
+}
+
+
+RawArray* Code::GetInlinedIdToFunction() const {
+  const Array& metadata = Array::Handle(raw_ptr()->inlined_metadata_);
+  if (metadata.IsNull()) {
+    return metadata.raw();
+  }
+  return reinterpret_cast<RawArray*>(
+      metadata.At(RawCode::kInlinedIdToFunctionIndex));
+}
+
+
+void Code::SetInlinedIdToFunction(const Array& value) const {
+  if (raw_ptr()->inlined_metadata_ == Array::null()) {
+    StorePointer(&raw_ptr()->inlined_metadata_,
+                 Array::New(RawCode::kInlinedMetadataSize, Heap::kOld));
+  }
+  const Array& metadata = Array::Handle(raw_ptr()->inlined_metadata_);
+  ASSERT(!metadata.IsNull());
+  ASSERT(metadata.IsOld());
+  ASSERT(value.IsOld());
+  metadata.SetAt(RawCode::kInlinedIdToFunctionIndex, value);
+}
+
+
 RawCode* Code::New(intptr_t pointer_offsets_length) {
   if (pointer_offsets_length < 0 || pointer_offsets_length > kMaxElements) {
     // This should be caught before we reach here.
     FATAL1("Fatal error in Code::New: invalid pointer_offsets_length %" Pd "\n",
            pointer_offsets_length);
   }
   ASSERT(Object::code_class() != Class::null());
   Code& result = Code::Handle();
   {
     uword size = Code::InstanceSize(pointer_offsets_length);
@@ skipping 82 matching lines @@
     if (FLAG_write_protect_code) {
       uword address = RawObject::ToAddr(instrs.raw());
       bool status = VirtualMemory::Protect(
           reinterpret_cast<void*>(address),
           instrs.raw()->Size(),
           VirtualMemory::kReadExecute);
       ASSERT(status);
     }
   }
   code.set_comments(assembler->GetCodeComments());
+  if (assembler->prologue_offset() >= 0) {
+    code.SetPrologueOffset(assembler->prologue_offset());
+  } else {
+    // No prologue was ever entered, optimistically assume nothing was ever
+    // pushed onto the stack.
+    code.SetPrologueOffset(assembler->CodeSize());
+  }
   INC_STAT(Isolate::Current(),
            total_code_size, code.comments().comments_.Length());
   return code.raw();
 }
 
 
 RawCode* Code::FinalizeCode(const Function& function,
                             Assembler* assembler,
                             bool optimized) {
   // Calling ToLibNamePrefixedQualifiedCString is very expensive,
@@ skipping 211 matching lines @@
       // Only disassemble alive code objects.
       DisassembleToJSONStream formatter(jsarr);
       Disassemble(&formatter);
     }
   }
   const PcDescriptors& descriptors = PcDescriptors::Handle(pc_descriptors());
   if (!descriptors.IsNull()) {
     JSONObject desc(&jsobj, "_descriptors");
     descriptors.PrintToJSONObject(&desc, false);
   }
-  const Array& inlined_function_table = Array::Handle(inlined_id_to_function());
+  const Array& inlined_function_table = Array::Handle(GetInlinedIdToFunction());
   if (!inlined_function_table.IsNull() &&
       (inlined_function_table.Length() > 0)) {
     JSONArray inlined_functions(&jsobj, "_inlinedFunctions");
     Function& function = Function::Handle();
     for (intptr_t i = 0; i < inlined_function_table.Length(); i++) {
       function ^= inlined_function_table.At(i);
       ASSERT(!function.IsNull());
       inlined_functions.AddValue(function);
     }
   }
-  const Array& intervals = Array::Handle(inlined_intervals());
+  const Array& intervals = Array::Handle(GetInlinedIntervals());
   if (!intervals.IsNull() && (intervals.Length() > 0)) {
     Smi& start = Smi::Handle();
     Smi& end = Smi::Handle();
     Smi& temp_smi = Smi::Handle();
     JSONArray inline_intervals(&jsobj, "_inlinedIntervals");
     for (intptr_t i = 0; i < intervals.Length() - Code::kInlIntNumEntries;
          i += Code::kInlIntNumEntries) {
       start ^= intervals.At(i + Code::kInlIntStart);
       if (start.IsNull()) {
         continue;
@@ skipping 59 matching lines @@
       return map->raw();  // We found a stack map for this frame.
     }
   }
   ASSERT(!is_optimized());
   return Stackmap::null();
 }
 
 
 intptr_t Code::GetCallerId(intptr_t inlined_id) const {
   if (inlined_id < 0) return -1;
-  const Array& intervals = Array::Handle(inlined_intervals());
+  const Array& intervals = Array::Handle(GetInlinedIntervals());
   if (intervals.IsNull() || (intervals.Length() == 0)) return -1;
   Smi& temp_smi = Smi::Handle();
   for (intptr_t i = 0; i < intervals.Length() - Code::kInlIntNumEntries;
        i += Code::kInlIntNumEntries) {
     temp_smi ^= intervals.At(i + Code::kInlIntInliningId);
     if (temp_smi.Value() == inlined_id) {
       temp_smi ^= intervals.At(i + Code::kInlIntCallerId);
       return temp_smi.Value();
     }
   }
   return -1;
 }
 
 
 void Code::GetInlinedFunctionsAt(
     intptr_t offset, GrowableArray<Function*>* fs) const {
   fs->Clear();
-  const Array& intervals = Array::Handle(inlined_intervals());
+  const Array& intervals = Array::Handle(GetInlinedIntervals());
   if (intervals.IsNull() || (intervals.Length() == 0)) {
     // E.g., for code stubs.
     return;
   }
   // First find the right interval. TODO(srdjan): use binary search since
   // intervals are sorted.
   Smi& start = Smi::Handle();
   Smi& end = Smi::Handle();
   intptr_t found_interval_ix = intervals.Length() - Code::kInlIntNumEntries;
   for (intptr_t i = 0; i < intervals.Length() - Code::kInlIntNumEntries;
        i += Code::kInlIntNumEntries) {
     start ^= intervals.At(i + Code::kInlIntStart);
     if (!start.IsNull()) {
       end ^= intervals.At(i + Code::kInlIntNumEntries + Code::kInlIntStart);
       if ((start.Value() <= offset) && (offset < end.Value())) {
         found_interval_ix = i;
         break;
       }
     }
   }
 
   // Find all functions.
-  const Array& id_map = Array::Handle(inlined_id_to_function());
+  const Array& id_map = Array::Handle(GetInlinedIdToFunction());
   Smi& temp_smi = Smi::Handle();
   temp_smi ^= intervals.At(found_interval_ix + Code::kInlIntInliningId);
   intptr_t inlining_id = temp_smi.Value();
   ASSERT(inlining_id >= 0);
   temp_smi ^= intervals.At(found_interval_ix + Code::kInlIntCallerId);
   intptr_t caller_id = temp_smi.Value();
   while (inlining_id >= 0) {
     Function& function = Function::ZoneHandle();
     function  ^= id_map.At(inlining_id);
     fs->Add(&function);
     inlining_id = caller_id;
     caller_id = GetCallerId(inlining_id);
   }
 }
 
 
 void Code::DumpInlinedIntervals() const {
   OS::Print("Inlined intervals:\n");
-  const Array& intervals = Array::Handle(inlined_intervals());
+  const Array& intervals = Array::Handle(GetInlinedIntervals());
   if (intervals.IsNull() || (intervals.Length() == 0)) return;
   Smi& start = Smi::Handle();
   Smi& inlining_id = Smi::Handle();
   Smi& caller_id = Smi::Handle();
   for (intptr_t i = 0; i < intervals.Length(); i += Code::kInlIntNumEntries) {
     start ^= intervals.At(i + Code::kInlIntStart);
     ASSERT(!start.IsNull());
     if (start.IsNull()) continue;
     inlining_id ^= intervals.At(i + Code::kInlIntInliningId);
     caller_id ^= intervals.At(i + Code::kInlIntCallerId);
     OS::Print("  %" Px " id: %" Pd " caller-id: %" Pd " \n",
         start.Value(), inlining_id.Value(), caller_id.Value());
   }
   OS::Print("Inlined ids:\n");
-  const Array& id_map = Array::Handle(inlined_id_to_function());
+  const Array& id_map = Array::Handle(GetInlinedIdToFunction());
   Function& function = Function::Handle();
   for (intptr_t i = 0; i < id_map.Length(); i++) {
     function ^= id_map.At(i);
     if (!function.IsNull()) {
       OS::Print("  %" Pd ": %s\n", i, function.ToQualifiedCString());
     }
   }
 }
 
 
@@ skipping 7935 matching lines @@
   return tag_label.ToCString();
 }
 
 
 void UserTag::PrintJSONImpl(JSONStream* stream, bool ref) const {
   Instance::PrintJSONImpl(stream, ref);
 }
 
 
 }  // namespace dart