MIPS: Use JIC/JIALC offset when possible

src/debug/mips/debug-mips.cc

 // Copyright 2012 the V8 project authors. All rights reserved.
 // Use of this source code is governed by a BSD-style license that can be
 // found in the LICENSE file.
 
 #if V8_TARGET_ARCH_MIPS
 
 #include "src/debug/debug.h"
 
 #include "src/codegen.h"
 #include "src/debug/liveedit.h"
@@ skipping 35 matching lines @@
   DCHECK(code->is_debug_stub());
   CodePatcher patcher(isolate, pc, Assembler::kDebugBreakSlotInstructions);
   // Patch the code changing the debug break slot code from:
   //   nop(DEBUG_BREAK_NOP) - nop(1) is sll(zero_reg, zero_reg, 1)
   //   nop(DEBUG_BREAK_NOP)
   //   nop(DEBUG_BREAK_NOP)
   //   nop(DEBUG_BREAK_NOP)
   // to a call to the debug break slot code.
   //   li t9, address   (lui t9 / ori t9 instruction pair)
   //   call t9          (jalr t9 / nop instruction pair)
+
+  // Add a label for checking the size of the code used for returning.
+  Label check_codesize;
+  patcher.masm()->bind(&check_codesize);
   patcher.masm()->li(v8::internal::t9,
                      Operand(reinterpret_cast<int32_t>(code->entry())));
   patcher.masm()->Call(v8::internal::t9);
+
+  // Check that the size of the code generated is as expected.
+  DCHECK_EQ(Assembler::kDebugBreakSlotLength,
+            patcher.masm()->SizeOfCodeGeneratedSince(&check_codesize));
 }
 
 bool DebugCodegen::DebugBreakSlotIsPatched(Address pc) {
   Instr current_instr = Assembler::instr_at(pc);
   return !Assembler::IsNop(current_instr, Assembler::DEBUG_BREAK_NOP);
 }
 
 void DebugCodegen::GenerateDebugBreakStub(MacroAssembler* masm,
                                           DebugBreakCallHelperMode mode) {
   __ RecordComment("Debug break");
@@ skipping 70 matching lines @@
 
 
 const bool LiveEdit::kFrameDropperSupported = true;
 
 #undef __
 
 }  // namespace internal
 }  // namespace v8
 
 #endif  // V8_TARGET_ARCH_MIPS