45 lines
900 B
PHP
45 lines
900 B
PHP
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<?php
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declare(strict_types=1);
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namespace SimAVRPHP;
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use SimAVRPHP\Exceptions\InvalidAddressException;
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class ProgramCounter
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{
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private const int RESET_PC_VALUE = 0;
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private int $programCounter = self::RESET_PC_VALUE;
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public function get(): int
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{
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return $this->programCounter;
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}
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public function jump(int $address): void
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{
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if (($address % 2) != 0) {
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throw new InvalidAddressException("Invalid address", $address);
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}
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$this->programCounter = $address;
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}
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public function relativeJump(int $address): void
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{
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$this->jump($this->programCounter + $address);
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}
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public function stepWords(int $word): int
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{
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$this->programCounter += ($word << 1);
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return $this->programCounter;
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}
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public function reset(): void
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{
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$this->programCounter = self::RESET_PC_VALUE;
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}
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}
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