Start working on supporting the Z-Machine version 3 (#19)

curiousdannii · Jul 27, 2016 · 6ede6f3 · 6ede6f3
1 parent 68be937
commit 6ede6f3
Show file tree

Hide file tree

Showing 4 changed files with 28 additions and 12 deletions.
diff --git a/src/zvm.js b/src/zvm.js
@@ -1,6 +1,6 @@
 /*
 
-ZVM - the ifvms.js Z-Machine (versions 5 and 8)
+ZVM - the ifvms.js Z-Machine (versions 3, 5 and 8)
 ===============================================
 
 Copyright (c) 2016 The ifvms.js team

diff --git a/src/zvm/disassembler.js b/src/zvm/disassembler.js
@@ -19,13 +19,13 @@ TODO:
 
 */
 
-var AST = require( '../common/ast.js' ),
-opcodes = require( './opcodes.js' );
+var AST = require( '../common/ast.js' );
 
 module.exports.disassemble = function()
 {
 	var pc, offset, // Set in the loop below
 	memory = this.m,
+	opcodes = this.opcodes,
 	temp,
 	code,
 	opcode_class,

diff --git a/src/zvm/opcodes.js b/src/zvm/opcodes.js
@@ -33,14 +33,15 @@ opcode_builder = AST.opcode_builder,
 simple_func = function( a ) { return '' + a; },
 
 // Common opcodes
-alwaysbranch = opcode_builder( AST.Brancher, function() { return 1; } ),
+alwaysbranch = opcode_builder( Brancher, function() { return 1; } ),
+not = opcode_builder( Storer, function( a ) { return 'e.S2U(~' + a + ')'; } ),
 
 // Indirect storer opcodes - rather non-generic I'm afraid
 // Not used for inc/dec
 // @load (variable) -> (result)
 // @pull (variable)
 // @store (variable) value
-Indirect = AST.Storer.subClass({
+Indirect = Storer.subClass({
 	storer: 0,
 
 	post: function()
@@ -89,7 +90,10 @@ Incdec = Opcode.subClass({
 /*eslint brace-style: "off" */
 /*eslint indent: "off" */
 
-module.exports = {
+module.exports = function( version )
+{
+
+return {
 
 /* je */ 1: opcode_builder( Brancher, function() { return arguments.length === 2 ? this.args( '===' ) : 'e.jeq(' + this.args() + ')'; } ),
 /* jl */ 2: opcode_builder( Brancher, function( a, b ) { return a.U2S() + '<' + b.U2S(); } ),
@@ -135,18 +139,25 @@ module.exports = {
 /* jump */ 140: opcode_builder( Stopper, function( a ) { return 'e.pc=' + a.U2S() + '+' + ( this.next - 2 ); } ),
 /* print_paddr */ 141: opcode_builder( Opcode, function( addr ) { return 'e.print(2,' + addr + '*' + this.e.addr_multipler + ')'; } ),
 /* load */ 142: Indirect.subClass( { storer: 1 } ),
-/* call_1n */ 143: Caller,
+143: version === 3 ?
+	/* not (v3) */ not :
+	/* call_1n (v5/8) */ Caller,
 /* rtrue */ 176: opcode_builder( Stopper, function() { return 'return 1'; } ),
 /* rfalse */ 177: opcode_builder( Stopper, function() { return 'return 0'; } ),
 // Reconsider a generalised class for @print/@print_ret?
 /* print */ 178: opcode_builder( Opcode, function( text ) { return 'e.print(2,' + text + ')'; }, { printer: 1 } ),
 /* print_ret */ 179: opcode_builder( Stopper, function( text ) { return 'e.print(2,' + text + ');e.print(1,13);return 1'; }, { printer: 1 } ),
 /* nop */ 180: Opcode,
+/* save (v3) */
+/* restore (v3) */
 /* restart */ 183: opcode_builder( Stopper, function() { return 'e.act(183)'; } ),
 /* ret_popped */ 184: opcode_builder( Stopper, function( a ) { return 'return ' + a; }, { post: function() { this.operands.push( new Variable( this.e, 0 ) ); } } ),
-/* catch */ 185: opcode_builder( Storer, function() { return 'e.call_stack.length'; } ),
+185: version === 3 ?
+	/* pop (v3) */ 0 : // TODO :
+	/* catch (v5/8) */ opcode_builder( Storer, function() { return 'e.call_stack.length'; } ),
 /* quit */ 186: opcode_builder( Stopper, function() { return 'e.act(186)'; } ),
 /* new_line */ 187: opcode_builder( Opcode, function() { return 'e.print(1,13)'; } ),
+/* show_status (v3) */
 /* verify */ 189: alwaysbranch, // Actually check??
 /* piracy */ 191: alwaysbranch,
 /* call_vs */ 224: CallerStorer,
@@ -173,7 +184,7 @@ module.exports = {
 /* sound_effect */ 245: Opcode, // We don't support sounds
 /* read_char */ 246: opcode_builder( Pauser, function() { return 'e.read_char(' + ( this.args() || '1' ) + ',' + this.storer.v + ')'; } ),
 /* scan_table */ 247: opcode_builder( BrancherStorer, function() { return 'e.scan_table(' + this.args() + ')'; } ),
-/* not */ 248: opcode_builder( Storer, function( a ) { return 'e.S2U(~' + a + ')'; } ),
+/* not (v5/8) */ 248: not,
 /* call_vn */ 249: Caller,
 /* call_vn2 */ 250: Caller,
 /* tokenise */ 251: opcode_builder( Opcode, function() { return 'e.tokenise(' + this.args() + ')'; } ),
@@ -198,3 +209,5 @@ module.exports = {
 /* parchment */ //1031: opcode_builder( Storer, function() { return 'e.op_parchment(' + this.args() + ')'; } ),
 
 };
+
+};
diff --git a/src/zvm/runtime.js b/src/zvm/runtime.js
@@ -445,7 +445,7 @@ module.exports = {
 		// Try to find the property
 		addr = this.find_prop( object, property );
 
-		( memory.getUint8( addr - 1 ) & 0x40 ? memory.setUint16 : memory.setUint8 )( addr, value );
+		memory[ memory.getUint8( addr - 1 ) & 0x40 ? 'setUint16' : 'setUint8' ]( addr, value );
 	},
 
 	random: function( range )
@@ -560,12 +560,12 @@ module.exports = {
 		var memory = utils.MemoryView( this.data ),
 
 		version = memory.getUint8( 0x00 ),
-		addr_multipler = version === 5 ? 4 : 8,
+		addr_multipler = version === 3 ? 2 : ( version === 5 ? 4 : 8 ),
 		property_defaults = memory.getUint16( 0x0A ),
 		extension = memory.getUint16( 0x36 );
 
 		// Check if the version is supported
-		if ( version !== 5 && version !== 8 )
+		if ( version !== 3 && version !== 5 && version !== 8 )
 		{
 			throw new Error( 'Unsupported Z-Machine version: ' + version );
 		}
@@ -603,6 +603,9 @@ module.exports = {
 			// Routine and string multiplier
 			addr_multipler: addr_multipler,
 
+			// Opcodes for this version of the Z-Machine
+			opcodes: require( './opcodes.js' )( version ),
+
 		});
 
 		this.ui = new ( require( './ui.js' ) )( this, memory.getUint8( 0x11 ) & 0x02 );