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Added more tests, function calls work

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Fixed a bunch of bugs in other opcodes, too
This commit is contained in:
Mitchell Plamann
2015-03-28 19:14:10 -04:00
parent 6774610569
commit 9159cf1389
28 changed files with 412 additions and 28 deletions
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74
src/c0vm.js
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@@ -1,10 +1,17 @@
op = require("./opcodes");
var INT_MIN = 0x80000000;
var INT_MAX = 0x7FFFFFFF;
var verbose = false;
function log(message) {
if (verbose) console.log(message);
}
function c0_assertion_failure(val) {
throw "c0 assertion failure: " + val;
}
var StackFrame = function(file, f) {
log("Creating stack frame");
this.stack = [];
@@ -12,7 +19,7 @@ var StackFrame = function(file, f) {
this.program = f.code;
this.variables = [];
for (var i = 0; i < f.num_vars; i++)
variables.push(0);
this.variables.push(0);
this.file = file;
}
@@ -21,7 +28,7 @@ var ProgramState = function(parsed_file) {
var main_function = parsed_file.function_pool[0];
this.frame = new StackFrame(parsed_file, parsed_file.function_pool[0]);
this.call_stack = [this.frame];
this.call_stack = [];
this.file = parsed_file;
}
@@ -33,13 +40,23 @@ ProgramState.prototype.pop = function() {
return this.frame.stack.pop();
}
ProgramState.prototype.goto_offset = function() {
var c1 = this.frame.program[this.frame.pc+1];
var c2 = this.frame.program[this.frame.pc+2]
var address_offset = (c1 << 8) + c2;
// Handle negative values
if ((address_offset & 0x8000) != 0)
address_offset = -0x8000 + (address_offset & 0x7FFF);
this.frame.pc += address_offset;
}
ProgramState.prototype.doIf = function(f) {
var y = this.pop();
var x = this.pop();
if (f(x,y)) {
var address_offset = (this.frame.program[this.frame.pc+1] * 0x1000) +
this.frame.program[this.frame.pc+2];
this.frame.pc += address_offset;
this.goto_offset();
} else {
this.frame.pc += 3;
}
@@ -47,7 +64,7 @@ ProgramState.prototype.doIf = function(f) {
ProgramState.prototype.step = function() {
var opcode = this.frame.program[this.frame.pc]
log("Running opcode " +
log("0x" + this.frame.pc.toString(16) + " Running opcode " +
op.lookup_table[opcode]);
switch (opcode) {
// Stack manipulation
@@ -81,8 +98,13 @@ ProgramState.prototype.step = function() {
// Returning from a function
case op.RETURN:
var retVal = this.pop();
throw retVal;
if (this.call_stack.length == 0)
throw retVal;
this.frame = this.call_stack.pop();
this.push(retVal);
break;
// Arithmetic
case op.IADD:
this.frame.pc++;
@@ -200,20 +222,20 @@ ProgramState.prototype.step = function() {
case op.IF_CMPNE:
this.doIf(function (x,y) {return y != x;});
break;
case op.IF_CMPLT:
case op.IF_ICMPLT:
this.doIf(function (x,y) {return y > x;});
break;
case op.IF_CMPGE:
case op.IF_ICMPGE:
this.doIf(function (x,y) {return y <= x;});
break;
case op.IF_CMPGT:
case op.IF_ICMPGT:
this.doIf(function (x,y) {return y < x;});
break;
case op.IF_CMPLE:
case op.IF_ICMPLE:
this.doIf(function (x,y) {return y >= x;});
break;
case op.GOTO:
this.doIf(function (x,y) {return true;});
this.goto_offset();
break;
case op.ATHROW:
this.frame.pc++;
@@ -226,8 +248,34 @@ ProgramState.prototype.step = function() {
c0_assertion_failure(a);
break;
// Function call operations
case op.INVOKESTATIC:
var c1 = this.frame.program[this.frame.pc+1];
var c2 = this.frame.program[this.frame.pc+2];
this.frame.pc += 3;
var index = (c1 << 8) + c2;
var f = this.file.function_pool[index];
var newFrame = new StackFrame(this.file, f);
for (var i = f.num_args - 1; i >= 0; i--) {
newFrame.variables[i] = this.pop();
}
this.call_stack.push(this.frame);
this.frame = newFrame;
break;
default:
console.log("Error: Unknown opcode: 0x" + opcode.toString(16) + "\n");
var opcode_name;
try {
opcode_name = op.lookup_table[opcode];
} catch (ignored) {
opcode_name = "UNKNOWN";
}
console.log("Error: Unknown opcode: 0x" + opcode.toString(16) +
" (" + opcode_name + ")\n");
throw "Error - unknown opcode";
}
return false;