Initial SIMDBC interpreter.

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 50 matching lines @@
   }
 }
 
 
 void ExitFrame::VisitObjectPointers(ObjectPointerVisitor* visitor) {
   // There are no objects to visit in this frame.
 }
 
 
 void EntryFrame::VisitObjectPointers(ObjectPointerVisitor* visitor) {
+#if !defined(TARGET_ARCH_DBC)
   ASSERT(thread() == Thread::Current());
   // Visit objects between SP and (FP - callee_save_area).
   ASSERT(visitor != NULL);
   RawObject** first = reinterpret_cast<RawObject**>(sp());
   RawObject** last = reinterpret_cast<RawObject**>(
       fp() + (kExitLinkSlotFromEntryFp - 1) * kWordSize);
   visitor->VisitPointers(first, last);
+#else
+  // On DBC stack is growing upwards which implies fp() <= sp().
+  RawObject** first = reinterpret_cast<RawObject**>(fp());
+  RawObject** last = reinterpret_cast<RawObject**>(sp());
+  visitor->VisitPointers(first, last);
+#endif
 }
 
 
 void StackFrame::VisitObjectPointers(ObjectPointerVisitor* visitor) {
+#if !defined(TARGET_ARCH_DBC)
   // NOTE: This code runs while GC is in progress and runs within
   // a NoHandleScope block. Hence it is not ok to use regular Zone or
   // Scope handles. We use direct stack handles, the raw pointers in
   // these handles are not traversed. The use of handles is mainly to
   // be able to reuse the handle based code and avoid having to add
   // helper functions to the raw object interface.
   ASSERT(thread() == Thread::Current());
   ASSERT(visitor != NULL);
   NoSafepointScope no_safepoint;
   Code code;
@@ skipping 58 matching lines @@
       visitor->VisitPointers(first, last);
       return;
     }
   }
   // For normal unoptimized Dart frames and Stub frames each slot
   // between the first and last included are tagged objects.
   RawObject** first = reinterpret_cast<RawObject**>(sp());
   RawObject** last = reinterpret_cast<RawObject**>(
       fp() + (kFirstObjectSlotFromFp * kWordSize));
   visitor->VisitPointers(first, last);
+#else
+  // On DBC stack grows upwards: fp() <= sp().
+  RawObject** first = reinterpret_cast<RawObject**>(
+      fp() + (kFirstObjectSlotFromFp * kWordSize));
+  RawObject** last = reinterpret_cast<RawObject**>(sp());
+  visitor->VisitPointers(first, last);
+#endif  // !defined(TARGET_ARCH_DBC)
 }
 
 
 RawFunction* StackFrame::LookupDartFunction() const {
   const Code& code = Code::Handle(LookupDartCode());
   if (!code.IsNull()) {
     return code.function();
   }
   return Function::null();
 }
@@ skipping 140 matching lines @@
       current_frame_(NULL),
       thread_(thread) {
   ASSERT((thread_ == Thread::Current()) ||
          OS::AllowStackFrameIteratorFromAnotherThread());
   frames_.fp_ = last_fp;
   frames_.sp_ = 0;
   frames_.pc_ = 0;
 }
 
 
+#if !defined(TARGET_ARCH_DBC)
 StackFrameIterator::StackFrameIterator(uword fp, uword sp, uword pc,
                                        bool validate, Thread* thread)
     : validate_(validate),
       entry_(thread),
       exit_(thread),
       frames_(thread),
       current_frame_(NULL),
       thread_(thread) {
   ASSERT((thread_ == Thread::Current()) ||
          OS::AllowStackFrameIteratorFromAnotherThread());
   frames_.fp_ = fp;
   frames_.sp_ = sp;
   frames_.pc_ = pc;
 }
+#endif
 
 
 StackFrame* StackFrameIterator::NextFrame() {
   // When we are at the start of iteration after having created an
   // iterator object, current_frame_ will be NULL as we haven't seen
   // any frames yet (unless we start iterating in the simulator from a given
   // triplet of fp, sp, and pc). At this point, if NextFrame is called, it tries
   // to set up the next exit frame by reading the top_exit_frame_info
   // from the isolate. If we do not have any dart invocations yet,
   // top_exit_frame_info will be 0 and so we would return NULL.
 
   // current_frame_ will also be NULL, when we are at the end of having
   // iterated through all the frames. If NextFrame is called at this
   // point, we will try and set up the next exit frame, but since we are
   // at the end of the iteration, fp_ will be 0 and we would return NULL.
   if (current_frame_ == NULL) {
     if (!HasNextFrame()) {
       return NULL;
     }
     UnpoisonStack(frames_.fp_);
+#if !defined(TARGET_ARCH_DBC)
     if (frames_.pc_ == 0) {
       // Iteration starts from an exit frame given by its fp.
       current_frame_ = NextExitFrame();
     } else if (*(reinterpret_cast<uword*>(
         frames_.fp_ + (kSavedCallerFpSlotFromFp * kWordSize))) == 0) {
       // Iteration starts from an entry frame given by its fp, sp, and pc.
       current_frame_ = NextEntryFrame();
     } else {
       // Iteration starts from a Dart or stub frame given by its fp, sp, and pc.
       current_frame_ = frames_.NextFrame(validate_);
     }
+#else
+    // Iteration starts from an exit frame given by its fp. This is the only
+    // mode supported on DBC.
+    ASSERT(frames_.pc_ == 0);
+    current_frame_ = NextExitFrame();
+#endif  // !defined(TARGET_ARCH_DBC)
     return current_frame_;
   }
   ASSERT((validate_ == kDontValidateFrames) || current_frame_->IsValid());
   if (current_frame_->IsEntryFrame()) {
     if (HasNextFrame()) {  // We have another chained block.
       current_frame_ = NextExitFrame();
       return current_frame_;
     }
     current_frame_ = NULL;  // No more frames.
     return current_frame_;
@@ skipping 115 matching lines @@
     if (deopt_instr->kind() == DeoptInstr::kCallerFp) {
       return (index - num_materializations_);
     }
   }
   UNREACHABLE();
   return 0;
 }
 
 
 }  // namespace dart