Synchronize with r15701.

src/a64/deoptimizer-a64.cc

 // Copyright 2013 the V8 project authors. All rights reserved.
 // Redistribution and use in source and binary forms, with or without
 // modification, are permitted provided that the following conditions are
 // met:
 //
 //     * Redistributions of source code must retain the above copyright
 //       notice, this list of conditions and the following disclaimer.
 //     * Redistributions in binary form must reproduce the above
 //       copyright notice, this list of conditions and the following
 //       disclaimer in the documentation and/or other materials provided
@@ skipping 415 matching lines @@
       (saved_registers.Count() * kXRegSizeInBytes) +
       (saved_fp_registers.Count() * kDRegSizeInBytes);
 
   // Floating point registers are saved on the stack above core registers.
   const int kFPRegistersOffset = saved_registers.Count() * kXRegSizeInBytes;
 
   // Get the bailout id from the stack.
   Register bailout_id = x2;
   __ Peek(bailout_id, kSavedRegistersAreaSize);
 
-  // Get the address of the location in the code object if possible
-  // and compute the fp-to-sp delta.
   Register code_object = x3;
   Register fp_to_sp = x4;
-  if ((type() == EAGER) || (type() == SOFT)) {
-    __ Mov(code_object, 0);
-    // Correct one word for bailout id.
-    __ Add(fp_to_sp,
-           masm()->StackPointer(),
-           kSavedRegistersAreaSize + (1 * kPointerSize));
-  } else if (type() == OSR) {
-    __ Mov(code_object, lr);
-    // Correct one word for bailout id.
-    __ Add(fp_to_sp,
-           masm()->StackPointer(),
-           kSavedRegistersAreaSize + (1 * kPointerSize));
-  } else {
-    __ Mov(code_object, lr);
-    // Correct two words for bailout id and return address.
-    __ Add(fp_to_sp,
-           masm()->StackPointer(),
-           kSavedRegistersAreaSize + (2 * kPointerSize));
-  }
+  // Get the address of the location in the code object. This is the return
+  // address for lazy deoptimization.
+  __ Mov(code_object, lr);
+  // Compute the fp-to-sp delta, and correct one word for bailout id.
+  __ Add(fp_to_sp, masm()->StackPointer(),
+         kSavedRegistersAreaSize + (1 * kPointerSize));
   __ Sub(fp_to_sp, fp, fp_to_sp);
 
   // Allocate a new deoptimizer object.
   __ Ldr(x0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
   __ Mov(x1, type());
   // Following arguments are already loaded:
   //  - x2: bailout id
   //  - x3: code object address
   //  - x4: fp-to-sp delta
   __ Mov(x5, Operand(ExternalReference::isolate_address(isolate())));
@@ skipping 24 matching lines @@
   // Copy FP registers to the input frame.
   for (int i = 0; i < saved_fp_registers.Count(); i++) {
     // TODO(all): Look for opportunities to optimize this by using ldp/stp.
     int dst_offset = FrameDescription::double_registers_offset() +
         (i * kDoubleSize);
     int src_offset = kFPRegistersOffset + (i * kDoubleSize);
     __ Peek(x2, src_offset);
     __ Str(x2, MemOperand(x1, dst_offset));
   }
 
-  // Remove the bailout id, eventually return address, and the saved registers
-  // from the stack.
-  if ((type() == EAGER) || (type() == SOFT) || (type() == OSR)) {
-    __ Drop(1 + (kSavedRegistersAreaSize / kXRegSizeInBytes));
-  } else {
-    // Also remove return address for lazy deopt.
-    __ Drop(2 + (kSavedRegistersAreaSize / kXRegSizeInBytes));
-  }
+  // Remove the bailout id and the saved registers from the stack.
+  __ Drop(1 + (kSavedRegistersAreaSize / kXRegSizeInBytes));
 
   // Compute a pointer to the unwinding limit in register x2; that is
   // the first stack slot not part of the input frame.
   Register unwind_limit = x2;
   __ Ldr(unwind_limit, MemOperand(x1, FrameDescription::frame_size_offset()));
   __ Add(unwind_limit, unwind_limit, __ StackPointer());
 
   // Unwind the stack down to - but not including - the unwinding
   // limit and copy the contents of the activation frame to the input
   // frame description.
@@ skipping 83 matching lines @@
   __ Ldr(continuation, MemOperand(last_output_frame,
                                   FrameDescription::continuation_offset()));
   __ Ldr(lr, MemOperand(last_output_frame, FrameDescription::pc_offset()));
   __ InitializeRootRegister();
   __ Br(continuation);
 }
 
 
 // Size of an entry of the second level deopt table.
 // This is the code size generated by GeneratePrologue for one entry.
-const int Deoptimizer::table_entry_size_ = 4 * kInstructionSize;
+const int Deoptimizer::table_entry_size_ = 2 * kInstructionSize;
 
 
 void Deoptimizer::TableEntryGenerator::GeneratePrologue() {
   // Create a sequence of deoptimization entries.
-  // Note that any registers may be still live.
+  // Note that registers are still live when jumping to an entry.
   Label done;
   {
     InstructionAccurateScope scope(masm());
 
     // The number of entry will never exceed kMaxNumberOfEntries.
     // As long as kMaxNumberOfEntries is a valid 16 bits immediate you can use
     // a movz instruction to load the entry id.
     ASSERT(is_uint16(Deoptimizer::kMaxNumberOfEntries));
 
     for (int i = 0; i < count(); i++) {
       int start = masm()->pc_offset();
       USE(start);
-      if ((type() == EAGER) || (type() == SOFT)) {
-        // These nops are fillers; all entries must be the same size.
-        __ nop();
-        __ nop();
-      } else {
-        // Push lr on the stack.
-        // We cannot use Push from the MacroAssembler here since we are in an
-        // instruction accurate scope.
-        __ sub(csp, jssp, kPointerSize);
-        __ str(lr, MemOperand(jssp, -kPointerSize, PreIndex));
-      }
-
       __ movz(masm()->Tmp0(), i);
       __ b(&done);
       ASSERT(masm()->pc_offset() - start == table_entry_size_);
     }
   }
   __ Bind(&done);
   // TODO(all): We need to add some kind of assertion to verify that Tmp0()
   // is not clobbered by Push.
   __ Push(masm()->Tmp0());
 }
 
 #undef __
 
 } }  // namespace v8::internal