bool LDAAbsXInstr::exp(asmjit::X86Assembler& a, MemoryMapper& m) { auto temp = asmjit::x86::rax; a.mov(temp, this->base); a.add(temp, REG_X); auto tmpPtr = asmjit::x86::byte_ptr(temp); { auto NotZero = a.newLabel(); auto Exit = a.newLabel(); a.cmp(tmpPtr, 0); a.jne(NotZero); // Value was 0 a.bts(REG_S, S_ZERO); a.jmp(Exit); // Value was not 0 a.bind(NotZero); a.btr(REG_S, S_ZERO); //No jmp required, just fall though a.bind(Exit); } a.mov(REG_A, tmpPtr); return true; }
bool LDAImmInstr::exp(asmjit::X86Assembler& a, MemoryMapper& m) { a.mov(REG_A, this->value); // Immediate mode knows the value at compile time, so just emit the right // thing if(this->value == 0) a.bts(REG_S, S_ZERO); else a.btr(REG_S, S_ZERO); if((this->value & 0x80) == 0) a.btr(REG_S, S_NEGATIVE); else a.bts(REG_S, S_NEGATIVE); return true; }
bool CMPImm::exp(asmjit::X86Assembler& a, MemoryMapper& m) { a.cmp(REG_A, this->operand); { a.pushfd(); a.btr(REG_S, S_CARRY); a.popfd(); auto End = a.newLabel(); a.jnc(End); a.pushfd(); a.bts(REG_S, S_CARRY); a.popfd(); a.bind(End); } { a.pushfd(); a.btr(REG_S, S_ZERO); a.popfd(); auto End = a.newLabel(); a.jne(End); a.pushfd(); a.bts(REG_S, S_ZERO); a.popfd(); a.bind(End); } { a.pushfd(); a.btr(REG_S, S_NEGATIVE); a.popfd(); auto End = a.newLabel(); a.jns(End); a.pushfd(); a.bts(REG_S, S_NEGATIVE); a.popfd(); a.bind(End); } return true; }
bool BITZeroP::exp(asmjit::X86Assembler& a, MemoryMapper& m) { m.emitLoad(a, operand, asmjit::x86::al); // @COMPLETENESS: We should check and set the S_ flags here before the and a.push(asmjit::x86::rax); a.and_(asmjit::x86::al, REG_A); auto Zero = a.newLabel(); auto Exit = a.newLabel(); a.jz(Zero); //Not zero a.btr(REG_S, S_ZERO); a.jmp(Exit); a.bind(Zero); a.bts(REG_S, S_ZERO); a.bind(Exit); a.pop(asmjit::x86::rax); { a.btr(REG_S, S_OVERFLOW); a.bt(asmjit::x86::al, 6); auto End = a.newLabel(); a.jnc(End); a.bts(REG_S, S_OVERFLOW); a.bind(End); } { a.btr(REG_S, S_NEGATIVE); a.bt(asmjit::x86::al, 7); auto End = a.newLabel(); a.jnc(End); a.bts(REG_S, S_NEGATIVE); a.bind(End); } return true; }
bool CLC::exp(asmjit::X86Assembler& a, MemoryMapper& m) { a.btr(REG_S, S_CARRY); return true; }
bool CLD::exp(asmjit::X86Assembler& a, MemoryMapper& m) { a.btr(REG_S, S_DECIMAL); return true; }