Remove special-casing of EAGER and SOFT deoptimization calling conventions, allowing calling addres…

src/mips/deoptimizer-mips.cc

 
 // Copyright 2011 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
@@ skipping 439 matching lines @@
       __ sw(ToRegister(i), MemOperand(sp, kPointerSize * i));
     }
   }
 
   const int kSavedRegistersAreaSize =
       (kNumberOfRegisters * kPointerSize) + kDoubleRegsSize;
 
   // Get the bailout id from the stack.
   __ lw(a2, MemOperand(sp, kSavedRegistersAreaSize));
 
-  // Get the address of the location in the code object if possible (a3) (return
+  // Get the address of the location in the code object (a3) (return
   // address for lazy deoptimization) and compute the fp-to-sp delta in
   // register t0.
-  if (type() == EAGER || type() == SOFT) {
-    __ mov(a3, zero_reg);
-    // Correct one word for bailout id.
-    __ Addu(t0, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize)));
-  } else if (type() == OSR) {
-    __ mov(a3, ra);
-    // Correct one word for bailout id.
-    __ Addu(t0, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize)));
-  } else {
-    __ mov(a3, ra);
-    // Correct two words for bailout id and return address.
-    __ Addu(t0, sp, Operand(kSavedRegistersAreaSize + (2 * kPointerSize)));
-  }
+  __ mov(a3, ra);
+  // Correct one word for bailout id.
+  __ Addu(t0, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize)));
 
   __ Subu(t0, fp, t0);
 
   // Allocate a new deoptimizer object.
   // Pass four arguments in a0 to a3 and fifth & sixth arguments on stack.
   __ PrepareCallCFunction(6, t1);
   __ lw(a0, MemOperand(fp, JavaScriptFrameConstants::kFunctionOffset));
   __ li(a1, Operand(type()));  // bailout type,
   // a2: bailout id already loaded.
   // a3: code address or 0 already loaded.
@@ skipping 28 matching lines @@
   int double_regs_offset = FrameDescription::double_registers_offset();
   // Copy FPU registers to
   // double_registers_[DoubleRegister::kNumAllocatableRegisters]
   for (int i = 0; i < FPURegister::NumAllocatableRegisters(); ++i) {
     int dst_offset = i * kDoubleSize + double_regs_offset;
     int src_offset = i * kDoubleSize + kNumberOfRegisters * kPointerSize;
     __ ldc1(f0, MemOperand(sp, src_offset));
     __ sdc1(f0, MemOperand(a1, dst_offset));
   }
 
-  // Remove the bailout id, eventually return address, and the saved registers
-  // from the stack.
-  if (type() == EAGER || type() == SOFT || type() == OSR) {
-    __ Addu(sp, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize)));
-  } else {
-    __ Addu(sp, sp, Operand(kSavedRegistersAreaSize + (2 * kPointerSize)));
-  }
+  // Remove the bailout id and the saved registers from the stack.
+  __ Addu(sp, sp, Operand(kSavedRegistersAreaSize + (1 * kPointerSize)));
 
   // Compute a pointer to the unwinding limit in register a2; that is
   // the first stack slot not part of the input frame.
   __ lw(a2, MemOperand(a1, FrameDescription::frame_size_offset()));
   __ Addu(a2, a2, sp);
 
   // Unwind the stack down to - but not including - the unwinding
   // limit and copy the contents of the activation frame to the input
   // frame description.
   __ Addu(a3, a1, Operand(FrameDescription::frame_content_offset()));
@@ skipping 80 matching lines @@
   __ InitializeRootRegister();
 
   __ pop(at);  // Get continuation, leave pc on stack.
   __ pop(ra);
   __ Jump(at);
   __ stop("Unreachable.");
 }
 
 
 // Maximum size of a table entry generated below.
-const int Deoptimizer::table_entry_size_ = 9 * Assembler::kInstrSize;
+const int Deoptimizer::table_entry_size_ = 6 * Assembler::kInstrSize;
 
 void Deoptimizer::TableEntryGenerator::GeneratePrologue() {
   Assembler::BlockTrampolinePoolScope block_trampoline_pool(masm());
 
-  // Create a sequence of deoptimization entries. Note that any
-  // registers may be still live.
+  // Create a sequence of deoptimization entries.
+  // Note that registers are still live when jumping to an entry.
   Label table_start;
   __ bind(&table_start);
   for (int i = 0; i < count(); i++) {
     Label start;
     __ bind(&start);
-    if (type() != EAGER && type() != SOFT) {
-      // Emulate ia32 like call by pushing return address to stack.
-      __ addiu(sp, sp, -2 * kPointerSize);
-      __ sw(ra, MemOperand(sp, 1 * kPointerSize));
-    } else {
-      __ addiu(sp, sp, -1 * kPointerSize);
-    }
+    __ addiu(sp, sp, -1 * kPointerSize);
     // Jump over the remaining deopt entries (including this one).
     // This code is always reached by calling Jump, which puts the target (label
     // start) into t9.
     const int remaining_entries = (count() - i) * table_entry_size_;
     __ Addu(t9, t9, remaining_entries);
     // 'at' was clobbered so we can only load the current entry value here.
     __ li(at, i);
     __ jr(t9);  // Expose delay slot.
     __ sw(at, MemOperand(sp, 0 * kPointerSize));  // In the delay slot.
 
     // Pad the rest of the code.
     while (table_entry_size_ > (masm()->SizeOfCodeGeneratedSince(&start))) {
       __ nop();
     }
 
     ASSERT_EQ(table_entry_size_, masm()->SizeOfCodeGeneratedSince(&start));
   }
 
   ASSERT_EQ(masm()->SizeOfCodeGeneratedSince(&table_start),
       count() * table_entry_size_);
 }
 
 #undef __
 
 
 } }  // namespace v8::internal