Make deoptimization architecture dependent (it depends on the frame layout).

runtime/vm/code_generator.cc

 // Copyright (c) 2013, 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/code_generator.h"
 
 #include "vm/assembler.h"
 #include "vm/ast.h"
 #include "vm/bigint_operations.h"
 #include "vm/code_patcher.h"
@@ skipping 1471 matching lines @@
 
 // Copy optimized frame into the isolate buffer.
 // The first incoming argument is stored at the last entry in the
 // copied frame buffer.
 static void CopyFrame(const Code& optimized_code, const StackFrame& frame) {
   const Function& function = Function::Handle(optimized_code.function());
   // Do not copy incoming arguments if there are optional arguments (they
   // are copied into local space at method entry).
   const intptr_t num_args =
       function.HasOptionalParameters() ? 0 : function.num_fixed_parameters();
-  // FP, PC-marker and return-address will be copied as well.
+  // The fixed size section of the (fake) Dart frame called via a stub by the
+  // optimized function contains FP, PP (ARM and MIPS only), PC-marker and
+  // return-address. This section is copied as well, so that its contained
+  // values can be updated before returning to the deoptimized function.
   const intptr_t frame_copy_size =
-      // Deoptimized function's return address: caller_frame->pc().
-      - kSavedPcSlotFromSp
-      + ((frame.fp() - frame.sp()) / kWordSize)
+      + kDartFrameFixedSize  // For saved values below sp.
+      + ((frame.fp() - frame.sp()) / kWordSize)  // For frame size incl. sp.
       + 1  // For fp.
-      + kParamEndSlotFromFp
-      + num_args;
+      + kParamEndSlotFromFp  // For saved values above fp.
+      + num_args;  // For arguments.
   intptr_t* frame_copy = new intptr_t[frame_copy_size];
   ASSERT(frame_copy != NULL);
-  // Include the return address of optimized code.
   intptr_t* start = reinterpret_cast<intptr_t*>(
-      frame.sp() + (kSavedPcSlotFromSp * kWordSize));
+      frame.sp() - (kDartFrameFixedSize * kWordSize));
   for (intptr_t i = 0; i < frame_copy_size; i++) {
     frame_copy[i] = *(start + i);
   }
   Isolate::Current()->SetDeoptFrameCopy(frame_copy, frame_copy_size);
 }
 
 
 // Copies saved registers and caller's frame into temporary buffers.
 // Returns the stack size of unoptimized frame.
 DEFINE_LEAF_RUNTIME_ENTRY(intptr_t, DeoptimizeCopyFrame,
                           uword saved_registers_address) {
   Isolate* isolate = Isolate::Current();
   StackZone zone(isolate);
   HANDLESCOPE(isolate);
 
-  // All registers have been saved below last-fp.
-  // Note that the deopt stub is not allowed to save any other values (pc
-  // marker, pool pointer, alignment, etc...) below last-fp.
-  const uword last_fp = saved_registers_address +
-                        kNumberOfCpuRegisters * kWordSize +
-                        kNumberOfFpuRegisters * kFpuRegisterSize;
+  // All registers have been saved below last-fp as if they were locals.
+  const uword last_fp = saved_registers_address
+                        + (kNumberOfCpuRegisters * kWordSize)
+                        + (kNumberOfFpuRegisters * kFpuRegisterSize)
+                        - ((kFirstLocalSlotFromFp + 1) * kWordSize);
   CopySavedRegisters(saved_registers_address);
 
   // Get optimized code and frame that need to be deoptimized.
   DartFrameIterator iterator(last_fp);
   StackFrame* caller_frame = iterator.NextFrame();
   ASSERT(caller_frame != NULL);
   const Code& optimized_code = Code::Handle(caller_frame->LookupDartCode());
   ASSERT(optimized_code.is_optimized());
 
   intptr_t deopt_reason = kDeoptUnknown;
@@ skipping 12 matching lines @@
         function.ToFullyQualifiedCString(),
         function.deoptimization_counter());
   }
 
   // Compute the stack size of the unoptimized frame.  For functions with
   // optional arguments the deoptimization info does not describe the
   // incoming arguments.
   const Function& function = Function::Handle(optimized_code.function());
   const intptr_t num_args =
       function.HasOptionalParameters() ? 0 : function.num_fixed_parameters();
-  intptr_t unoptimized_stack_size =
+  const intptr_t unoptimized_stack_size =
       + deopt_info.FrameSize()
+      - kDartFrameFixedSize
       - num_args
       - kParamEndSlotFromFp
       - 1;  // For fp.
-  return unoptimized_stack_size * kWordSize;
+  return unoptimized_stack_size * kWordSize;  // Stack size (FP - SP) in bytes.
 }
 END_LEAF_RUNTIME_ENTRY
 
 
-static intptr_t DeoptimizeWithDeoptInfo(const Code& code,
-                                        const DeoptInfo& deopt_info,
-                                        const StackFrame& caller_frame,
-                                        intptr_t deopt_reason) {
+static void DeoptimizeWithDeoptInfo(const Code& code,
+                                    const DeoptInfo& deopt_info,
+                                    const StackFrame& caller_frame,
+                                    intptr_t deopt_reason) {
   const intptr_t len = deopt_info.TranslationLength();
   GrowableArray<DeoptInstr*> deopt_instructions(len);
   const Array& deopt_table = Array::Handle(code.deopt_info_array());
   ASSERT(!deopt_table.IsNull());
   deopt_info.ToInstructions(deopt_table, &deopt_instructions);
 
   intptr_t* start = reinterpret_cast<intptr_t*>(
-      caller_frame.sp() + (kSavedPcSlotFromSp * kWordSize));
+      caller_frame.sp() - (kDartFrameFixedSize * kWordSize));
   const Function& function = Function::Handle(code.function());
   const intptr_t num_args =
       function.HasOptionalParameters() ? 0 : function.num_fixed_parameters();
   const intptr_t to_frame_size =
-      - kSavedPcSlotFromSp  // Deoptimized function's return address.
+      + kDartFrameFixedSize  // For saved values below sp.
       + (caller_frame.fp() - caller_frame.sp()) / kWordSize
       + 1  // For fp.
       + kParamEndSlotFromFp
       + num_args;
   DeoptimizationContext deopt_context(start,
                                       to_frame_size,
                                       Array::Handle(code.object_table()),
                                       num_args,
                                       static_cast<DeoptReasonId>(deopt_reason));
   const intptr_t frame_size = deopt_info.FrameSize();
 
   // All kMaterializeObject instructions are emitted before the instructions
   // that describe stack frames. Skip them and defer materialization of
   // objects until the frame is fully reconstructed and it is safe to perform
   // GC.
   // Arguments (class of the instance to allocate and field-value pairs) are
   // described as part of the expression stack for the bottom-most deoptimized
   // frame. They will be used during materialization and removed from the stack
   // right before control switches to the unoptimized code.
   const intptr_t num_materializations = len - frame_size;
   Isolate::Current()->PrepareForDeferredMaterialization(num_materializations);
-  for (intptr_t from_index = 0, to_index = 1;
+  for (intptr_t from_index = 0, to_index = kDartFrameFixedSize;
        from_index < num_materializations;
        from_index++) {
     const intptr_t field_count =
         DeoptInstr::GetFieldCount(deopt_instructions[from_index]);
     intptr_t* args = deopt_context.GetToFrameAddressAt(to_index);
     DeferredObject* obj = new DeferredObject(field_count, args);
     Isolate::Current()->SetDeferredObjectAt(from_index, obj);
     to_index += obj->ArgumentCount();
   }
 
   // Populate stack frames.
   for (intptr_t to_index = frame_size - 1, from_index = len - 1;
        to_index >= 0;
        to_index--, from_index--) {
     intptr_t* to_addr = deopt_context.GetToFrameAddressAt(to_index);
     deopt_instructions[from_index]->Execute(&deopt_context, to_addr);
   }
 
   if (FLAG_trace_deoptimization_verbose) {
     for (intptr_t i = 0; i < frame_size; i++) {
       OS::PrintErr("*%"Pd". [%"Px"] %#014"Px" [%s]\n",
                    i,
                    reinterpret_cast<uword>(&start[i]),
                    start[i],
                    deopt_instructions[i + (len - frame_size)]->ToCString());
     }
   }
-  return deopt_context.GetCallerFp();
 }
 
 
 // The stack has been adjusted to fit all values for unoptimized frame.
 // Fill the unoptimized frame.
-DEFINE_LEAF_RUNTIME_ENTRY(intptr_t, DeoptimizeFillFrame, uword last_fp) {
+DEFINE_LEAF_RUNTIME_ENTRY(void, DeoptimizeFillFrame, uword last_fp) {
   Isolate* isolate = Isolate::Current();
   StackZone zone(isolate);
   HANDLESCOPE(isolate);
 
   DartFrameIterator iterator(last_fp);
   StackFrame* caller_frame = iterator.NextFrame();
   ASSERT(caller_frame != NULL);
   const Code& optimized_code = Code::Handle(caller_frame->LookupDartCode());
   const Function& function = Function::Handle(optimized_code.function());
   ASSERT(!function.IsNull());
   const Code& unoptimized_code = Code::Handle(function.unoptimized_code());
   ASSERT(!optimized_code.IsNull() && optimized_code.is_optimized());
   ASSERT(!unoptimized_code.IsNull() && !unoptimized_code.is_optimized());
 
   intptr_t* frame_copy = isolate->deopt_frame_copy();
   intptr_t* cpu_registers_copy = isolate->deopt_cpu_registers_copy();
   fpu_register_t* fpu_registers_copy = isolate->deopt_fpu_registers_copy();
 
   intptr_t deopt_reason = kDeoptUnknown;
   const DeoptInfo& deopt_info = DeoptInfo::Handle(
       optimized_code.GetDeoptInfoAtPc(caller_frame->pc(), &deopt_reason));
   ASSERT(!deopt_info.IsNull());
 
-  const intptr_t caller_fp = DeoptimizeWithDeoptInfo(optimized_code,
-                                                     deopt_info,
-                                                     *caller_frame,
-                                                     deopt_reason);
+  DeoptimizeWithDeoptInfo(optimized_code,
+                          deopt_info,
+                          *caller_frame,
+                          deopt_reason);
 
   isolate->SetDeoptFrameCopy(NULL, 0);
   isolate->set_deopt_cpu_registers_copy(NULL);
   isolate->set_deopt_fpu_registers_copy(NULL);
   delete[] frame_copy;
   delete[] cpu_registers_copy;
   delete[] fpu_registers_copy;
-
-  return caller_fp;
 }
 END_LEAF_RUNTIME_ENTRY
 
 
 // This is the last step in the deoptimization, GC can occur.
 // Returns number of bytes to remove from the expression stack of the
 // bottom-most deoptimized frame. Those arguments were artificially injected
 // under return address to keep them discoverable by GC that can occur during
 // materialization phase.
 DEFINE_RUNTIME_ENTRY(DeoptimizeMaterialize, 0) {
@@ skipping 72 matching lines @@
 //   Arg1: Value that is being stored.
 DEFINE_RUNTIME_ENTRY(UpdateFieldCid, 2) {
   ASSERT(arguments.ArgCount() == kUpdateFieldCidRuntimeEntry.argument_count());
   const Field& field = Field::CheckedHandle(arguments.ArgAt(0));
   const Object& value = Object::Handle(arguments.ArgAt(1));
 
   field.UpdateCid(Class::Handle(value.clazz()).id());
 }
 
 }  // namespace dart