instructions.html
来自「MIPS Simulator assembly languge.」· HTML 代码 · 共 873 行 · 第 1/2 页
HTML
873 行
<!-- File: Instructions.html
----
---- Author: Dr. D. Hunkins
---- Date: October 2004
---- Modified: 6 June 2005
---->
<html>
<head>
<LINK HREF="pathsim.css" REL="stylesheet" type="text/css">
<title>Instructions</title>
<script language="JavaScript">
// An address as communicated between this and the Java applet is
// a logical address (i.e., a multiple of 4) and it is a
// hex string
function valueOf(c) {
if (("0" <= c) && (c <= "9")) return (c-"0");
switch (c) {
case "A" :
case "a" : return 10;
case "B" :
case "b" : return 11;
case "C" :
case "c" : return 12;
case "D" :
case "d" : return 13;
case "E" :
case "e" : return 14;
case "F" :
case "f" : return 15;
}
}
function hexStringToUnsigned(address) {
var value = 0;
for (var i=0; i<address.length; i++)
value = 16*value + valueOf(address.charAt(i));
return value;
}
function unsignedToHexString(number, numberOfDigits) {
var result = "";
var intermediateValue = number;
var digitValue;
var digitCount = 0;
var temp;
while (true){
digitValue = (intermediateValue % 16);
switch (digitValue){
case 0: result = "0" + result;
break;
case 1: result = "1" + result;
break;
case 2: result = "2" + result;
break;
case 3: result = "3" + result;
break;
case 4: result = "4" + result;
break;
case 5: result = "5" + result;
break;
case 6: result = "6" + result;
break;
case 7: result = "7" + result;
break;
case 8: result = "8" + result;
break;
case 9: result = "9" + result;
break;
case 10: result = "A" + result;
break;
case 11: result = "B" + result;
break;
case 12: result = "C" + result;
break;
case 13: result = "D" + result;
break;
case 14: result = "E" + result;
break;
case 15: result = "F" + result;
break;
}
digitCount++;
temp = "" + (intermediateValue /= 16);
if (temp.indexOf(".") == 0)
intermediateValue = 0;
else
if (temp.indexOf(".") == -1) {
temp = temp.substr(0);
intermediateValue = Number(temp);
}
else {
temp = temp.substr(0, temp.indexOf("."));
intermediateValue = Number(temp);
}
if ((intermediateValue == 0) || (digitCount == numberOfDigits)) break;
}
while (result.length < numberOfDigits)
result = "0" + result;
return result;
}
function isLetter(c) {
return ( ("a" <= c) && (c <= "z") );
}
function isDecimalDigit(c) {
return ( ("0" <= c) && (c <= "9") );
}
function isHexDigit(c) {
return ( (("0" <= c) && (c <= "9")) ||
(("A" <= c) && (c <= "F")) );
}
function isHexNumber(token, numberOfDigits) {
token = token.toUpperCase();
if (token.length == 0) return false;
for (var i=0; i<token.length; i++)
if (!isHexDigit(token.charAt(i))) return false;
if (token.length > numberOfDigits) return false;
return true;
}
function isRegister(token) {
return ( (token == "$at") || (token == "$v0") || (token == "$v1") || (token == "$a0") || (token == "$a1") ||
(token == "$a2") || (token == "$a3") || (token == "$t0") || (token == "$t1") || (token == "$t2") ||
(token == "$t3") || (token == "$t4") || (token == "$t5") || (token == "$t6") || (token == "$t7") ||
(token == "$s0") || (token == "$s1") || (token == "$s2") || (token == "$s3") || (token == "$s4") ||
(token == "$s5") || (token == "$s6") || (token == "$s7") || (token == "$t8") || (token == "$t9") ||
(token == "$k0") || (token == "$s1") || (token == "$gp") || (token == "$sp") || (token == "$fp") ||
(token == "$ra") || (token == "$zero") );
}
function isConstantRegister(token) {
return (token == "$zero");
}
function getRegisterNumber(token) {
switch (token) {
case "$at" : return "01";
break;
case "$v0" : return "02";
break;
case "$v1" : return "03";
break;
case "$a0" : return "04";
break;
case "$a1" : return "05";
break;
case "$a2" : return "06";
break;
case "$a3" : return "07";
break;
case "$t0" : return "08";
break;
case "$t1" : return "09";
break;
case "$t2" : return "0A";
break;
case "$t3" : return "0B";
break;
case "$t4" : return "0C";
break;
case "$t5" : return "0D";
break;
case "$t6" : return "0E";
break;
case "$t7" : return "0F";
break;
case "$s0" : return "10";
break;
case "$s1" : return "11";
break;
case "$s2" : return "12";
break;
case "$s3" : return "13";
break;
case "$s4" : return "14";
break;
case "$s5" : return "15";
break;
case "$s6" : return "16";
break;
case "$s7" : return "17";
break;
case "$t8" : return "18";
break;
case "$t9" : return "19";
break;
case "$k0" : return "1A";
break;
case "$k1" : return "1B";
break;
case "$gp" : return "1C";
break;
case "$sp" : return "1D";
break;
case "$fp" : return "1E";
break;
case "$ra" : return "1F";
break;
case "$zero" : return "00";
break;
}
}
function fourFieldInstruction(instructionComponents) {
var temp = hexStringToUnsigned(instructionComponents[0]) & 60;
var word = unsignedToHexString(Math.floor(temp/4), 1);
temp = (hexStringToUnsigned(instructionComponents[0]) & 3)*4;
temp += Math.floor((hexStringToUnsigned(instructionComponents[1]) & 24)/8);
word += unsignedToHexString(temp, 1);
temp = (hexStringToUnsigned(instructionComponents[1]) & 7)*2;
temp += Math.floor((hexStringToUnsigned(instructionComponents[2]) & 16)/16);
word += unsignedToHexString(temp, 1);
temp = hexStringToUnsigned(instructionComponents[2]) & 15;
word += unsignedToHexString(temp, 1);
temp = hexStringToUnsigned(instructionComponents[3]);
word += unsignedToHexString(temp, 4);
return word;
}
function twoFieldInstruction(instructionComponents) {
var temp = hexStringToUnsigned(instructionComponents[0]) & 60;
var word = unsignedToHexString(Math.floor(temp/4), 1);
temp = (hexStringToUnsigned(instructionComponents[0]) & 3)*4;
word += unsignedToHexString(temp, 1);
temp = hexStringToUnsigned(instructionComponents[1]);
word += unsignedToHexString(temp, 6);
return word;
}
function sixFieldInstruction(instructionComponents) {
var temp = hexStringToUnsigned(instructionComponents[0]) & 60;
var word = unsignedToHexString(Math.floor(temp/4), 1);
temp = (hexStringToUnsigned(instructionComponents[0]) & 3)*4;
temp += Math.floor((hexStringToUnsigned(instructionComponents[1]) & 24)/8);
word += unsignedToHexString(temp, 1);
temp = (hexStringToUnsigned(instructionComponents[1]) & 7)*2;
temp += Math.floor((hexStringToUnsigned(instructionComponents[2]) & 16)/16);
word += unsignedToHexString(temp, 1);
temp = hexStringToUnsigned(instructionComponents[2]) & 15;
word += unsignedToHexString(temp, 1);
temp = Math.floor((hexStringToUnsigned(instructionComponents[3]) & 30)/2);
word += unsignedToHexString(temp, 1);
temp = (hexStringToUnsigned(instructionComponents[3]) & 1)*8;
temp += Math.floor((hexStringToUnsigned(instructionComponents[4]) & 28)/4);
word += unsignedToHexString(temp, 1);
temp = (hexStringToUnsigned(instructionComponents[4]) & 3)*4;
temp += Math.floor((hexStringToUnsigned(instructionComponents[5]) & 48)/16);
word += unsignedToHexString(temp, 1);
temp = hexStringToUnsigned(instructionComponents[5]) & 15;
word += unsignedToHexString(temp, 1);
return word;
}
function immediateType() {
try {
var instructionComponents = new Array();
var operation = this.tokenList.shift();
switch (operation) {
case "addi" : instructionComponents[0] = "08";
break;
case "andi" : instructionComponents[0] = "0C";
break;
case "ori" : instructionComponents[0] = "0D";
break;
case "xori" : instructionComponents[0] = "0E";
break;
}
var token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected in first!!");
if (isConstantRegister(token))
throw new Error("$zero Register Cannot Be Changed!!");
instructionComponents[2] = getRegisterNumber(token);
token = this.tokenList.shift();
if (token != ",")
throw new Error("Comma Expected!!");
token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected in second!!");
instructionComponents[1] = getRegisterNumber(token);
token = this.tokenList.shift();
if (token != ",")
throw new Error("Comma Expected!!");
token = this.tokenList.shift();
if(!isHexNumber(token, 4))
throw new Error("Immediate Value of at most 4 Hex Digits Expected!!");
instructionComponents[3] = token.toUpperCase();
if (this.tokenList.length != 0)
throw new Error("Extra text follows instruction!!");
this.instructions.push(fourFieldInstruction(instructionComponents));
}
catch(ex) {
throw ex;
}
}
function immediateShift() {
try {
var instructionComponents = new Array();
var operation = this.tokenList.shift();
switch (operation) {
case "sll" : instructionComponents[5] = "00";
break;
case "sra" : instructionComponents[5] = "03";
break;
case "srl" : instructionComponents[5] = "02";
break;
}
instructionComponents[0] = "00";
instructionComponents[1] = "00";
var token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected!!");
if (isConstantRegister(token))
throw new Error("$zero Register Cannot Be Changed!!");
instructionComponents[3] = getRegisterNumber(token);
token = this.tokenList.shift();
if (token != ",")
throw new Error("Comma Expected!!");
token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected!");
instructionComponents[2] = getRegisterNumber(token);
token = this.tokenList.shift();
if (token != ",")
throw new Error("Comma Expected!!");
token = this.tokenList.shift();
if(!isHexNumber(token, 2))
throw new Error("Immediate Value of at most 2 Hex Digits Expected!!");
if (hexStringToUnsigned(token) > 31)
throw new Error("Shift amount must be in the range 0 to 31!!");
instructionComponents[4] = token.toUpperCase();
if (this.tokenList.length != 0)
throw new Error("Extra text follows instruction!!");
this.instructions.push(sixFieldInstruction(instructionComponents));
}
catch(ex) {
throw ex;
}
}
function variableShift() {
try {
var instructionComponents = new Array();
var operation = this.tokenList.shift();
switch (operation) {
case "sllv" : instructionComponents[5] = "04";
break;
case "srav" : instructionComponents[5] = "07";
break;
case "srlv" : instructionComponents[5] = "06";
break;
}
instructionComponents[0] = "00";
instructionComponents[4] = "00";
token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected!!");
if (isConstantRegister(token))
throw new Error("$zero Register Cannot Be Changed!!");
instructionComponents[3] = getRegisterNumber(token);
token = this.tokenList.shift();
if (token != ",")
throw new Error("Comma Expected!!");
token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected!");
instructionComponents[2] = getRegisterNumber(token);
token = this.tokenList.shift();
if (token != ",")
throw new Error("Comma Expected!!");
token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected!");
instructionComponents[1] = getRegisterNumber(token);
if (this.tokenList.length != 0)
throw new Error("Extra text follows instruction!!");
this.instructions.push(sixFieldInstruction(instructionComponents));
}
catch (ex) {
throw ex;
}
}
function dataTransfer() {
try {
var instructionComponents = new Array();
var operation = this.tokenList.shift();
if (operation == "lw")
instructionComponents[0] = "23";
else
instructionComponents[0] = "2B";
token = this.tokenList.shift();
if (!isRegister(token))
throw new Error("Register Expected!!");
if ((operation == "lw") && (isConstantRegister(token)))
throw new Error("$zero Register Cannot Be Changed!!");
instructionComponents[2] = getRegisterNumber(token);
token = this.tokenList.shift();
if (token != ",")
throw new Error("Comma Expected!!");
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