begin testing and make grammar more spec-compliant

7 files changed, 226 insertions, 175 deletions

diff --git a/src/parser/grammar.jison b/src/parser/grammar.jison
index edcca5c..4f4a433 100644
--- a/src/parser/grammar.jison
+++ b/src/parser/grammar.jison
@@ -110,46 +110,80 @@ row
 
 
 op
-	: opcode address "," address
-	{ $$ = { opcode: $opcode, a: $address1, b: $address2 }; }
-	| opcode address
-	{ 
+	: op_immediate_a { $$ = $1; }
+	| op_immediate_b { $$ = $1; }
+	| DAT dat_addr "," dat_addr { $$ = { opcode: $1, a: $dat_addr1, b: $dat_addr2 }; }
+	| DAT dat_addr              { $$ = { opcode: $1, a: $dat_addr1, b: { mode: 'immediate', value: 0 } }; }
+	;
+
+
+op_immediate_a
+	: opcode_immediate_a address "," non_immediate_addr
+	{ $$ = { opcode: $1, a: $2, b: $4 }; }
+	;
+
+op_immediate_b
+	: opcode_immediate_b non_immediate_addr "," address
+	{ $$ = { opcode: $1, a: $2, b: $4 }; }
+	| opcode_immediate_b non_immediate_addr 
+	{
 		$$ = {
-			opcode: $opcode,
-			a: $address,
+			opcode: $1,
+			a: $2,
 			b: { mode: 'direct', value: 0 },
 		};
 	}
 	;
 
 
-opcode
+
+opcode_immediate_a
 	: MOV { $$ = $1; }
 	| ADD { $$ = $1; }
 	| SUB { $$ = $1; }
 	| CMP { $$ = $1; }
 	| SLT { $$ = $1; }
-	| JMP { $$ = $1; }
+	;
+opcode_immediate_b
+	: JMP { $$ = $1; }
 	| JMZ { $$ = $1; }
 	| JMN { $$ = $1; }
 	| DJN { $$ = $1; }
 	| SPL { $$ = $1; }
-	| DAT { $$ = $1; }
 	;
 
 
 address
-	: address_mode e { $$ = { mode: $1, value: $2 }; }
-	| e              { $$ = { mode: 'direct', value: $1 }; }
+	: immediate_addr     { $$ = $1; }
+	| non_immediate_addr { $$ = $1; }
 	;
 
 
-address_mode
-	: "#" { $$ = 'immediate';    }
-	| "@" { $$ = 'indirect';     }
-	| "<" { $$ = 'predecrement'; }
-	| "$" { $$ = 'direct';       }
+non_immediate_addr
+	: direct_addr       { $$ = $1; }
+	| indirect_addr     { $$ = $1; }
+	| predecrement_addr { $$ = $1; }
 	;
+dat_addr
+	: immediate_addr    { $$ = $1; }
+	| predecrement_addr { $$ = $1; }
+	;
+
+immediate_addr
+	: "#" e { $$ = { mode: 'immediate', value: $e }; }
+	;
+direct_addr
+	: "$" e { $$ = { mode: 'direct', value: $e }; }
+	| e     { $$ = { mode: 'direct', value: $e }; }
+	;
+indirect_addr
+	: "@" e { $$ = { mode: 'indirect', value: $e }; }
+	;
+predecrement_addr
+	: "<" e { $$ = { mode: 'predecrement', value: $e }; }
+	;
+
+
 
 
 e
diff --git a/src/parser/grammar.js b/src/parser/grammar.js
index 6d055c7..6fa53b7 100644
--- a/src/parser/grammar.js
+++ b/src/parser/grammar.js
@@ -72,12 +72,12 @@
   }
 */
 var grammar = (function(){
-var o=function(k,v,o,l){for(o=o||{},l=k.length;l--;o[k[l]]=v);return o},$V0=[1,5],$V1=[1,10],$V2=[1,11],$V3=[1,12],$V4=[1,13],$V5=[1,14],$V6=[1,15],$V7=[1,16],$V8=[1,17],$V9=[1,18],$Va=[1,19],$Vb=[1,20],$Vc=[1,9],$Vd=[5,10,19,20,21,22,23,24,25,26,27,28,29,42],$Ve=[1,29],$Vf=[1,30],$Vg=[1,31],$Vh=[1,32],$Vi=[1,34],$Vj=[1,33],$Vk=[1,35],$Vl=[31,32,33,34,36,39,41,42],$Vm=[1,40],$Vn=[1,41],$Vo=[10,18],$Vp=[1,45],$Vq=[1,46],$Vr=[1,47],$Vs=[1,48],$Vt=[36,39,41,42],$Vu=[10,18,35,36,37,38,40],$Vv=[9,10],$Vw=[10,18,35,36,40];
+var o=function(k,v,o,l){for(o=o||{},l=k.length;l--;o[k[l]]=v);return o},$V0=[1,5],$V1=[1,10],$V2=[1,14],$V3=[1,15],$V4=[1,16],$V5=[1,17],$V6=[1,18],$V7=[1,19],$V8=[1,20],$V9=[1,21],$Va=[1,22],$Vb=[1,23],$Vc=[1,11],$Vd=[5,10,18,25,26,27,28,29,30,31,32,33,34,50],$Ve=[1,32],$Vf=[1,33],$Vg=[1,40],$Vh=[1,42],$Vi=[1,44],$Vj=[1,43],$Vk=[1,45],$Vl=[39,40,41,42,44,47,49,50],$Vm=[40,41,42,44,47,49,50],$Vn=[1,51],$Vo=[1,52],$Vp=[10,20],$Vq=[1,59],$Vr=[1,60],$Vs=[1,61],$Vt=[1,62],$Vu=[10,20,43,44,45,46,48],$Vv=[9,10],$Vw=[10,20,43,44,48];
 var parser = {trace: function trace () { },
 yy: {},
-symbols_: {"error":2,"program":3,"lines":4,"END":5,"coda":6,"label":7,"newlines":8,"EOF":9,"NEWLINE":10,"line":11,"row":12,"op":13,"EQU":14,"e":15,"opcode":16,"address":17,",":18,"MOV":19,"ADD":20,"SUB":21,"CMP":22,"SLT":23,"JMP":24,"JMZ":25,"JMN":26,"DJN":27,"SPL":28,"DAT":29,"address_mode":30,"#":31,"@":32,"<":33,"$":34,"+":35,"-":36,"*":37,"/":38,"(":39,")":40,"NUMBER":41,"LABEL":42,"$accept":0,"$end":1},
-terminals_: {2:"error",5:"END",9:"EOF",10:"NEWLINE",14:"EQU",18:",",19:"MOV",20:"ADD",21:"SUB",22:"CMP",23:"SLT",24:"JMP",25:"JMZ",26:"JMN",27:"DJN",28:"SPL",29:"DAT",31:"#",32:"@",33:"<",34:"$",35:"+",36:"-",37:"*",38:"/",39:"(",40:")",41:"NUMBER",42:"LABEL"},
-productions_: [0,[3,3],[3,4],[6,2],[6,1],[8,2],[8,1],[4,2],[4,1],[11,2],[11,1],[12,1],[12,2],[12,3],[13,4],[13,2],[16,1],[16,1],[16,1],[16,1],[16,1],[16,1],[16,1],[16,1],[16,1],[16,1],[16,1],[17,2],[17,1],[30,1],[30,1],[30,1],[30,1],[15,3],[15,3],[15,3],[15,3],[15,3],[15,2],[15,1],[15,1],[7,1]],
+symbols_: {"error":2,"program":3,"lines":4,"END":5,"coda":6,"label":7,"newlines":8,"EOF":9,"NEWLINE":10,"line":11,"row":12,"op":13,"EQU":14,"e":15,"op_immediate_a":16,"op_immediate_b":17,"DAT":18,"dat_addr":19,",":20,"opcode_immediate_a":21,"address":22,"non_immediate_addr":23,"opcode_immediate_b":24,"MOV":25,"ADD":26,"SUB":27,"CMP":28,"SLT":29,"JMP":30,"JMZ":31,"JMN":32,"DJN":33,"SPL":34,"immediate_addr":35,"direct_addr":36,"indirect_addr":37,"predecrement_addr":38,"#":39,"$":40,"@":41,"<":42,"+":43,"-":44,"*":45,"/":46,"(":47,")":48,"NUMBER":49,"LABEL":50,"$accept":0,"$end":1},
+terminals_: {2:"error",5:"END",9:"EOF",10:"NEWLINE",14:"EQU",18:"DAT",20:",",25:"MOV",26:"ADD",27:"SUB",28:"CMP",29:"SLT",30:"JMP",31:"JMZ",32:"JMN",33:"DJN",34:"SPL",39:"#",40:"$",41:"@",42:"<",43:"+",44:"-",45:"*",46:"/",47:"(",48:")",49:"NUMBER",50:"LABEL"},
+productions_: [0,[3,3],[3,4],[6,2],[6,1],[8,2],[8,1],[4,2],[4,1],[11,2],[11,1],[12,1],[12,2],[12,3],[13,1],[13,1],[13,4],[13,2],[16,4],[17,4],[17,2],[21,1],[21,1],[21,1],[21,1],[21,1],[24,1],[24,1],[24,1],[24,1],[24,1],[22,1],[22,1],[23,1],[23,1],[23,1],[19,1],[19,1],[35,2],[36,2],[36,1],[37,2],[38,2],[15,3],[15,3],[15,3],[15,3],[15,3],[15,2],[15,1],[15,1],[7,1]],
 performAction: function anonymous(yytext, yyleng, yylineno, yy, yystate /* action[1] */, $$ /* vstack */, _$ /* lstack */) {
 /* this == yyval */
 
@@ -131,11 +131,17 @@ case 13:
 		this.$ = null;
 	
 break;
-case 14:
+case 14: case 15: case 21: case 22: case 23: case 24: case 25: case 26: case 27: case 28: case 29: case 30: case 31: case 32: case 33: case 34: case 35: case 36: case 37:
+ this.$ = $$[$0]; 
+break;
+case 16: case 18: case 19:
  this.$ = { opcode: $$[$0-3], a: $$[$0-2], b: $$[$0] }; 
 break;
-case 15:
- 
+case 17:
+ this.$ = { opcode: $$[$0-1], a: $$[$0], b: { mode: 'immediate', value: 0 } }; 
+break;
+case 20:
+
 		this.$ = {
 			opcode: $$[$0-1],
 			a: $$[$0],
@@ -143,60 +149,51 @@ case 15:
 		};
 	
 break;
-case 16: case 17: case 18: case 19: case 20: case 21: case 22: case 23: case 24: case 25: case 26:
- this.$ = $$[$0]; 
-break;
-case 27:
- this.$ = { mode: $$[$0-1], value: $$[$0] }; 
+case 38:
+ this.$ = { mode: 'immediate', value: $$[$0] }; 
 break;
-case 28:
+case 39: case 40:
  this.$ = { mode: 'direct', value: $$[$0] }; 
 break;
-case 29:
- this.$ = 'immediate';    
-break;
-case 30:
- this.$ = 'indirect';     
-break;
-case 31:
- this.$ = 'predecrement'; 
+case 41:
+ this.$ = { mode: 'indirect', value: $$[$0] }; 
 break;
-case 32:
- this.$ = 'direct';       
+case 42:
+ this.$ = { mode: 'predecrement', value: $$[$0] }; 
 break;
-case 33:
+case 43:
  this.$ = Math.floor($$[$0-2] + $$[$0]); 
 break;
-case 34:
+case 44:
  this.$ = Math.floor($$[$0-2] - $$[$0]); 
 break;
-case 35:
+case 45:
  this.$ = Math.floor($$[$0-2] * $$[$0]); 
 break;
-case 36:
+case 46:
  this.$ = Math.floor($$[$0-2] / $$[$0]); 
 break;
-case 37:
+case 47:
  this.$ = Math.floor($$[$0-1]); 
 break;
-case 38:
+case 48:
  this.$ = - $$[$0]; 
 break;
-case 39:
+case 49:
  this.$ = Math.floor(Number(yytext)); 
 break;
-case 40:
+case 50:
 
 		this.$ = yy.getLabel($$[$0]);
 	
 break;
-case 41:
+case 51:
  this.$ = yytext; 
 break;
 }
 },
-table: [{3:1,4:2,7:7,10:$V0,11:3,12:4,13:6,16:8,19:$V1,20:$V2,21:$V3,22:$V4,23:$V5,24:$V6,25:$V7,26:$V8,27:$V9,28:$Va,29:$Vb,42:$Vc},{1:[3]},{5:[1,21],7:7,10:$V0,11:22,12:4,13:6,16:8,19:$V1,20:$V2,21:$V3,22:$V4,23:$V5,24:$V6,25:$V7,26:$V8,27:$V9,28:$Va,29:$Vb,42:$Vc},o($Vd,[2,8]),{10:[1,23]},o($Vd,[2,10]),{10:[2,11]},{13:24,14:[1,25],16:8,19:$V1,20:$V2,21:$V3,22:$V4,23:$V5,24:$V6,25:$V7,26:$V8,27:$V9,28:$Va,29:$Vb},{7:36,15:28,17:26,30:27,31:$Ve,32:$Vf,33:$Vg,34:$Vh,36:$Vi,39:$Vj,41:$Vk,42:$Vc},o([9,10,14,18,19,20,21,22,23,24,25,26,27,28,29,35,36,37,38,40],[2,41]),o($Vl,[2,16]),o($Vl,[2,17]),o($Vl,[2,18]),o($Vl,[2,19]),o($Vl,[2,20]),o($Vl,[2,21]),o($Vl,[2,22]),o($Vl,[2,23]),o($Vl,[2,24]),o($Vl,[2,25]),o($Vl,[2,26]),{6:37,7:38,8:39,9:$Vm,10:$Vn,42:$Vc},o($Vd,[2,7]),o($Vd,[2,9]),{10:[2,12]},{7:36,15:42,36:$Vi,39:$Vj,41:$Vk,42:$Vc},{10:[2,15],18:[1,43]},{7:36,15:44,36:$Vi,39:$Vj,41:$Vk,42:$Vc},o($Vo,[2,28],{35:$Vp,36:$Vq,37:$Vr,38:$Vs}),o($Vt,[2,29]),o($Vt,[2,30]),o($Vt,[2,31]),o($Vt,[2,32]),{7:36,15:49,36:$Vi,39:$Vj,41:$Vk,42:$Vc},{7:36,15:50,36:$Vi,39:$Vj,41:$Vk,42:$Vc},o($Vu,[2,39]),o($Vu,[2,40]),{1:[2,1]},{6:51,8:39,9:$Vm,10:$Vn},{9:[1,52],10:[1,53]},{1:[2,4]},o($Vv,[2,6]),{10:[2,13],35:$Vp,36:$Vq,37:$Vr,38:$Vs},{7:36,15:28,17:54,30:27,31:$Ve,32:$Vf,33:$Vg,34:$Vh,36:$Vi,39:$Vj,41:$Vk,42:$Vc},o($Vo,[2,27],{35:$Vp,36:$Vq,37:$Vr,38:$Vs}),{7:36,15:55,36:$Vi,39:$Vj,41:$Vk,42:$Vc},{7:36,15:56,36:$Vi,39:$Vj,41:$Vk,42:$Vc},{7:36,15:57,36:$Vi,39:$Vj,41:$Vk,42:$Vc},{7:36,15:58,36:$Vi,39:$Vj,41:$Vk,42:$Vc},{35:$Vp,36:$Vq,37:$Vr,38:$Vs,40:[1,59]},o($Vu,[2,38]),{1:[2,2]},{1:[2,3]},o($Vv,[2,5]),{10:[2,14]},o($Vw,[2,33],{37:$Vr,38:$Vs}),o($Vw,[2,34],{37:$Vr,38:$Vs}),o($Vu,[2,35]),o($Vu,[2,36]),o($Vu,[2,37])],
-defaultActions: {6:[2,11],24:[2,12],37:[2,1],40:[2,4],51:[2,2],52:[2,3],54:[2,14]},
+table: [{3:1,4:2,7:7,10:$V0,11:3,12:4,13:6,16:8,17:9,18:$V1,21:12,24:13,25:$V2,26:$V3,27:$V4,28:$V5,29:$V6,30:$V7,31:$V8,32:$V9,33:$Va,34:$Vb,50:$Vc},{1:[3]},{5:[1,24],7:7,10:$V0,11:25,12:4,13:6,16:8,17:9,18:$V1,21:12,24:13,25:$V2,26:$V3,27:$V4,28:$V5,29:$V6,30:$V7,31:$V8,32:$V9,33:$Va,34:$Vb,50:$Vc},o($Vd,[2,8]),{10:[1,26]},o($Vd,[2,10]),{10:[2,11]},{13:27,14:[1,28],16:8,17:9,18:$V1,21:12,24:13,25:$V2,26:$V3,27:$V4,28:$V5,29:$V6,30:$V7,31:$V8,32:$V9,33:$Va,34:$Vb},{10:[2,14]},{10:[2,15]},{19:29,35:30,38:31,39:$Ve,42:$Vf},o([9,10,14,18,20,25,26,27,28,29,30,31,32,33,34,43,44,45,46,48],[2,51]),{7:46,15:41,22:34,23:36,35:35,36:37,37:38,38:39,39:$Ve,40:$Vg,41:$Vh,42:$Vf,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{7:46,15:41,23:47,36:37,37:38,38:39,40:$Vg,41:$Vh,42:$Vf,44:$Vi,47:$Vj,49:$Vk,50:$Vc},o($Vl,[2,21]),o($Vl,[2,22]),o($Vl,[2,23]),o($Vl,[2,24]),o($Vl,[2,25]),o($Vm,[2,26]),o($Vm,[2,27]),o($Vm,[2,28]),o($Vm,[2,29]),o($Vm,[2,30]),{6:48,7:49,8:50,9:$Vn,10:$Vo,50:$Vc},o($Vd,[2,7]),o($Vd,[2,9]),{10:[2,12]},{7:46,15:53,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{10:[2,17],20:[1,54]},o($Vp,[2,36]),o($Vp,[2,37]),{7:46,15:55,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{7:46,15:56,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{20:[1,57]},o($Vp,[2,31]),o($Vp,[2,32]),o($Vp,[2,33]),o($Vp,[2,34]),o($Vp,[2,35]),{7:46,15:58,44:$Vi,47:$Vj,49:$Vk,50:$Vc},o($Vp,[2,40],{43:$Vq,44:$Vr,45:$Vs,46:$Vt}),{7:46,15:63,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{7:46,15:64,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{7:46,15:65,44:$Vi,47:$Vj,49:$Vk,50:$Vc},o($Vu,[2,49]),o($Vu,[2,50]),{10:[2,20],20:[1,66]},{1:[2,1]},{6:67,8:50,9:$Vn,10:$Vo},{9:[1,68],10:[1,69]},{1:[2,4]},o($Vv,[2,6]),{10:[2,13],43:$Vq,44:$Vr,45:$Vs,46:$Vt},{19:70,35:30,38:31,39:$Ve,42:$Vf},o($Vp,[2,38],{43:$Vq,44:$Vr,45:$Vs,46:$Vt}),o($Vp,[2,42],{43:$Vq,44:$Vr,45:$Vs,46:$Vt}),{7:46,15:41,23:71,36:37,37:38,38:39,40:$Vg,41:$Vh,42:$Vf,44:$Vi,47:$Vj,49:$Vk,50:$Vc},o($Vp,[2,39],{43:$Vq,44:$Vr,45:$Vs,46:$Vt}),{7:46,15:72,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{7:46,15:73,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{7:46,15:74,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{7:46,15:75,44:$Vi,47:$Vj,49:$Vk,50:$Vc},o($Vp,[2,41],{43:$Vq,44:$Vr,45:$Vs,46:$Vt}),{43:$Vq,44:$Vr,45:$Vs,46:$Vt,48:[1,76]},o($Vu,[2,48]),{7:46,15:41,22:77,23:36,35:35,36:37,37:38,38:39,39:$Ve,40:$Vg,41:$Vh,42:$Vf,44:$Vi,47:$Vj,49:$Vk,50:$Vc},{1:[2,2]},{1:[2,3]},o($Vv,[2,5]),{10:[2,16]},{10:[2,18]},o($Vw,[2,43],{45:$Vs,46:$Vt}),o($Vw,[2,44],{45:$Vs,46:$Vt}),o($Vu,[2,45]),o($Vu,[2,46]),o($Vu,[2,47]),{10:[2,19]}],
+defaultActions: {6:[2,11],8:[2,14],9:[2,15],27:[2,12],48:[2,1],51:[2,4],67:[2,2],68:[2,3],70:[2,16],71:[2,18],77:[2,19]},
 parseError: function parseError (str, hash) {
     if (hash.recoverable) {
         this.trace(str);
diff --git a/src/parser/parser.js b/src/parser/parser.js
index 8672832..3434fee 100644
--- a/src/parser/parser.js
+++ b/src/parser/parser.js
@@ -33,19 +33,19 @@ parser.yy = {
 };
 
 
-//if (process.argv[1] === 'parser.js' && process.argv.length >= 3) {
-	fs.readFile(process.argv[2], 'utf8', (err, data) => {
-		if (err) throw err;
-		let result = parser.parse(data.toUpperCase());
-		if (typeof(result.start) === "string") {
-			result.start = parser.yy.line[result.start];
-		}
-		for (let pc=0; pc<result.program.length; pc += 1) {
-			parser.yy.tidyAddress(pc, result.program[pc].a);
-			parser.yy.tidyAddress(pc, result.program[pc].b);
-		}
-		console.log(result.start);
-		console.log(result.program);
-		console.log(parser.yy);
-	});
-//}
+exports.assemble = function(sourceCode) {
+	let result = parser.parse(sourceCode.toUpperCase());
+
+	// set start point
+	if (typeof(result.start) === "string") {
+		result.start = parser.yy.line[result.start];
+	}
+
+	// convert line labels to actual numbers
+	for (let pc=0; pc<result.program.length; pc += 1) {
+		parser.yy.tidyAddress(pc, result.program[pc].a);
+		parser.yy.tidyAddress(pc, result.program[pc].b);
+	}
+
+	return result;
+}
diff --git a/src/parser/parser.test.js b/src/parser/parser.test.js
new file mode 100644
index 0000000..b496cdc
--- /dev/null
+++ b/src/parser/parser.test.js
@@ -0,0 +1,109 @@
+'use strict';
+
+const { assemble } = require('./parser.js');
+
+
+test('assemble the imp', () => {
+	expect(assemble(`
+		mov 0, 1
+		end
+	`)).toEqual({
+		start: 0,
+		program: [
+			{
+				opcode: 'MOV',
+				a: { mode: 'direct', value: 0 },
+				b: { mode: 'direct', value: 1 },
+			},
+		],
+	});
+});
+
+
+test('assemble dwarf', () => {
+	expect(assemble(`
+		bomb  dat #0
+		dwarf add #4, bomb
+		      mov bomb, @bomb
+		      jmp dwarf
+		end dwarf
+	`)).toEqual({
+		start: 1,
+		program: [
+			{ opcode: 'DAT',
+			  a: { mode: 'immediate', value: 0 },
+			  b: { mode: 'immediate', value: 0 },
+			},
+			{ opcode: 'ADD',
+			  a: { mode: 'immediate', value: 4 },
+			  b: { mode: 'direct', value: -1 },
+			},
+			{ opcode: 'MOV',
+			  a: { mode: 'direct', value: -2 },
+			  b: { mode: 'indirect', value: -2 },
+			},
+			{ opcode: 'JMP',
+			  a: { mode: 'direct', value: -2 },
+			  b: { mode: 'direct', value: 0 },
+			},
+		],
+	});
+});
+
+
+test('assemble armadillo', () => {
+	expect(assemble(`
+		; armadillo
+		; author: stefan strack
+		
+		bomb    spl 0
+		loop    add #3039, ptr
+		ptr     mov bomb, 81
+		        jmp loop
+		        mov 1, <-1
+		end bomb
+	`)).toEqual({
+		start: 0,
+		program: [
+			{ opcode: 'SPL',
+			  a: { mode: 'direct', value: 0 },
+			  b: { mode: 'direct', value: 0 },
+			},
+			{ opcode: 'ADD',
+			  a: { mode: 'immediate', value: 3039 },
+			  b: { mode: 'direct', value: 1 },
+			},
+			{ opcode: 'MOV',
+			  a: { mode: 'direct', value: -2 },
+			  b: { mode: 'direct', value: 81 },
+			},
+			{ opcode: 'JMP',
+			  a: { mode: 'direct', value: -2 },
+			  b: { mode: 'direct', value: 0 },
+			},
+			{ opcode: 'MOV',
+			  a: { mode: 'direct', value: 1 },
+			  b: { mode: 'predecrement', value: -1 },
+			},
+		],
+	});
+});
+
+
+test('illegal instructions are not assembled', () => {
+	expect(() => assemble("dat 0, #0\nend")).toThrow();
+	expect(() => assemble("dat @0, #0\nend")).toThrow();
+
+	expect(() => assemble("mov 0, #0\nend")).toThrow();
+	expect(() => assemble("add 0, #0\nend")).toThrow();
+	expect(() => assemble("sub 0, #0\nend")).toThrow();
+	expect(() => assemble("cmp 0, #0\nend")).toThrow();
+	expect(() => assemble("slt 0, #0\nend")).toThrow();
+
+	expect(() => assemble("jmp #0, 0\nend")).toThrow();
+	expect(() => assemble("jmz #0, 0\nend")).toThrow();
+	expect(() => assemble("jmn #0, 0\nend")).toThrow();
+	expect(() => assemble("jmn #0, 0\nend")).toThrow();
+	expect(() => assemble("djn #0, 0\nend")).toThrow();
+	expect(() => assemble("spl #0, 0\nend")).toThrow();
+});
diff --git a/src/vm/core.js b/src/vm/core.js
index 292ceb0..399cfc6 100644
--- a/src/vm/core.js
+++ b/src/vm/core.js
@@ -49,3 +49,6 @@ class Core {
 		return this.data[this.getLocation(pc, address)];
 	}
 }
+
+
+exports.Core = Core;
diff --git a/src/vm/instruction.js b/src/vm/instruction.js
index 0fe922d..ac4cd83 100644
--- a/src/vm/instruction.js
+++ b/src/vm/instruction.js
@@ -3,114 +3,7 @@
 const { AddrMode } = require('./enum.js');
 
 
-function DoDat(core, pc, ins) {
-	// do nothing
+exports.DAT = function(core, pc, ins) {
+	// do nothing and die
 	return [];
 }
-
-
-function DoMov(core, pc, ins) {
-	if (ins.a.mode === AddrMode.Immediate) {
-		let mem = core.getValue(pc, ins.b);
-		mem.b.value = ins.a.value;
-	} else {
-		const src = core.getValue(pc, ins.a);
-		const dstLoc = core.getLocation(pc, ins.b);
-
-		// hacky deep copy
-		core.data[dstLoc] = JSON.parse(JSON.stringify(src));
-	}
-	return [pc + 1];
-}
-
-
-function DoAdd(core, pc, ins) {
-	if (ins.a.mode === AddrMode.Immediate) {
-		let dst = core.getValue(pc, ins.b);
-		dst.b += ins.a.value;
-	} else {
-		let src = core.getValue(pc, ins.a);
-		let dst = core.getValue(pc, ins.b);
-		dst.a.value += src.a.value;
-		dst.b.value += src.b.value;
-	}
-	return [pc + 1];
-}
-
-
-function DoSub(core, pc, ins) {
-	if (ins.a.mode === AddrMode.Immediate) {
-		let dst = core.getValue(pc, ins.b);
-		dst.b -= ins.a.value;
-	} else {
-		let src = core.getValue(pc, ins.a);
-		let dst = core.getValue(pc, ins.b);
-		dst.a.value -= src.a.value;
-		dst.b.value -= src.b.value;
-	}
-	return [pc + 1];
-}
-
-
-function DoJmp(core, pc, ins) {
-	return [core.getLocation(pc, ins.a)];
-}
-
-
-function DoJmz(core, pc, ins) {
-	let test
-	if (ins.b.mode === AddrMode.Immediate) {
-		test = ins;
-	} else {
-		test = core.getValue(pc, ins.b);
-	}
-
-	if (test.b.value === 0) {
-		return [core.getLocation(pc, ins.a)];
-	} else {
-		return [pc + 1];
-	}
-}
-
-
-function DoJmn(core, pc, ins) {
-	let test
-	if (ins.b.mode === AddrMode.Immediate) {
-		test = ins;
-	} else {
-		test = core.getValue(pc, ins.b);
-	}
-
-	if (test.b.value !== 0) {
-		return [core.getLocation(pc, ins.a)];
-	} else {
-		return [pc + 1];
-	}
-}
-
-
-function DoCmp(core, pc, ins) {
-	if (ins.a.mode === AddrMode.Immediate) {
-		const test = core.getValue(pc, ins.b);
-		if (ins.a.value === test.b.value) {
-			return [pc + 2];
-		} else {
-			return [pc + 1];
-		}
-	} else {
-		const a = core.getValue(pc, ins.a);
-		const b = core.getValue(pc, ins.b);
-
-		if (
-			a.opcode === b.opcode &&
-			a.a.value === b.a.value &&
-			a.b.value === b.b.value)
-		) {
-			return [pc + 2];
-		} else {
-			return [pc + 1];
-		}
-	}
-}
-
-
diff --git a/src/vm/instruction.test.js b/src/vm/instruction.test.js
new file mode 100644
index 0000000..5dc7eea
--- /dev/null
+++ b/src/vm/instruction.test.js
@@ -0,0 +1,15 @@
+'use strict';
+
+const { Core } = require('./core.js');
+const { DAT } = require('./instruction.js');
+
+
+const CORESIZE = 8000;
+
+
+test('DAT does nothing and kills the program', () => {
+	const core = new Core(CORESIZE);
+	const pc = 0;
+	const ins = core.data[pc];
+	expect(DAT(core, pc, ins)).toEqual([]);
+});