MConstant* MBasicBlock::optimizedOutConstant(TempAllocator& alloc) { // If the first instruction is a MConstant(MagicValue(JS_OPTIMIZED_OUT)) // then reuse it. MInstruction* ins = *begin(); if (ins->type() == MIRType_MagicOptimizedOut) return ins->toConstant(); MConstant* constant = MConstant::New(alloc, MagicValue(JS_OPTIMIZED_OUT)); insertBefore(ins, constant); return constant; }