DBC: Fix reading locals out of a deopt frame.

runtime/vm/stack_frame.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/stack_frame.h"
 
 #include "platform/memory_sanitizer.h"
 #include "vm/assembler.h"
 #include "vm/deopt_instructions.h"
 #include "vm/isolate.h"
@@ skipping 471 matching lines @@
   entry_.pc_ = frames_.pc_;
   SetupNextExitFrameData();  // Setup data for next exit frame in chain.
   ASSERT(entry_.IsValid());
   return &entry_;
 }
 
 
 InlinedFunctionsIterator::InlinedFunctionsIterator(const Code& code, uword pc)
   : index_(0),
     num_materializations_(0),
+    dest_frame_size_(0),
     code_(Code::Handle(code.raw())),
     deopt_info_(TypedData::Handle()),
     function_(Function::Handle()),
     pc_(pc),
     deopt_instructions_(),
     object_table_(ObjectPool::Handle()) {
   ASSERT(code_.is_optimized());
   ASSERT(pc_ != 0);
   ASSERT(code.ContainsInstructionAt(pc));
   ICData::DeoptReasonId deopt_reason = ICData::kDeoptUnknown;
   uint32_t deopt_flags = 0;
   deopt_info_ = code_.GetDeoptInfoAtPc(pc, &deopt_reason, &deopt_flags);
   if (deopt_info_.IsNull()) {
     // This is the case when a call without deopt info in optimized code
     // throws an exception. (e.g. in the parameter copying prologue).
     // In that case there won't be any inlined frames.
     function_ = code_.function();
   } else {
     // Unpack deopt info into instructions (translate away suffixes).
     const Array& deopt_table = Array::Handle(code_.deopt_info_array());
     ASSERT(!deopt_table.IsNull());
     DeoptInfo::Unpack(deopt_table, deopt_info_, &deopt_instructions_);
     num_materializations_ = DeoptInfo::NumMaterializations(deopt_instructions_);
+    dest_frame_size_ = DeoptInfo::FrameSize(deopt_info_);
     object_table_ = code_.GetObjectPool();
     Advance();
   }
 }
 
 
 void InlinedFunctionsIterator::Advance() {
   // Iterate over the deopt instructions and determine the inlined
   // functions if any and iterate over them.
   ASSERT(!Done());
@@ skipping 18 matching lines @@
 
 // Finds the potential offset for the current function's FP if the
 // current frame were to be deoptimized.
 intptr_t InlinedFunctionsIterator::GetDeoptFpOffset() const {
   ASSERT(deopt_instructions_.length() != 0);
   for (intptr_t index = index_;
        index < deopt_instructions_.length();
        index++) {
     DeoptInstr* deopt_instr = deopt_instructions_[index];
     if (deopt_instr->kind() == DeoptInstr::kCallerFp) {
+#if defined(TARGET_ARCH_DBC)
+      // Stack on DBC is growing upwards but we record deopt commands
+      // in the same order we record them on other architectures as if
+      // the stack was growing downwards.
+      return dest_frame_size_ - index;
+#else
       return (index - num_materializations_);
+#endif
     }
   }
   UNREACHABLE();
   return 0;
 }
 
 
 }  // namespace dart