Split off literals table into its own module

Author: cscott

bcompile.js

@@ -40,7 +40,7 @@
 //
 // C. Scott Ananian
 // 2011-05-10 / 2020-02-12
-define(["text!bcompile.js", "bytecode-table"], function make_bcompile(bcompile_source, bytecode_table) {
+define(["text!bcompile.js", "bytecode-table", "literal-map"], function make_bcompile(bcompile_source, bytecode_table, LiteralMap) {
     // helper function for debugging
     var assert = function(b, obj) {
         if (!b) {
@@ -56,40 +56,15 @@ define(["text!bcompile.js", "bytecode-table"], function make_bcompile(bcompile_s
         // We also need to count lexical scope nesting depth during compilation
         var state = {
             functions: [],
-            literals: [],
+            literals: null,
             // internal
             scope: 0,
             desugar_frame_get: !dont_desugar_frame_get
         };
         // literal symbol table.  Does string intern'ing too.
-        var ObjectIs = Object.is || function(a, b) {
-            if (typeof(a)==='number' && typeof(b)==='number') {
-                if (a!==a) { return (b!==b); } // NaN
-                if (a===0) { return (b===0) && (1/a === 1/b); } // +/- 0
-            }
-            return (a===b);
-        };
-        var literalMap = Object.create(null);
-        state.literal = function(val) {
-            var i, pair, key, entries;
-            key = typeof(val) + ':' + val; // very basic hash key
-            entries = literalMap[key];
-            if (entries!==undefined) {
-                i = 0;
-                while (i < entries.length) {
-                    pair = entries[i];
-                    if (ObjectIs(pair[0], val)) { return pair[1]; }
-                    i += 1;
-                }
-            } else {
-                entries = [];
-                literalMap[key] = entries;
-            }
-            i = this.literals.length;
-            this.literals[i] = val;
-            entries.push([val, i]);
-            return i;
-        };
+        var lm = LiteralMap.New();
+        state.literals = lm.list;
+        state.literal = function(val) { return lm.get(val); };
         // create a function representation
         state.new_function = function(nargs) {
             var newf = {
@@ -755,7 +730,7 @@ define(["text!bcompile.js", "bytecode-table"], function make_bcompile(bcompile_s
     };
     bcompile.__module_name__ = "bcompile";
     bcompile.__module_init__ = make_bcompile;
-    bcompile.__module_deps__ = ["bytecode-table"];
+    bcompile.__module_deps__ = ["bytecode-table", "literal-map"];
     bcompile.__module_source__ = bcompile_source;
     return bcompile;
 });

binterp.js

@@ -111,13 +111,20 @@ define(["text!binterp.js", "bytecode-table"/*, "!html-escape"*/], function make_
         this.stack.push(na);
     };
     dispatch.new_function = function(idx) {
+        // See 14.1.20 InstantiateFunctionObject
+        // OrdinaryFunctionCreate
         var f = Object.create(MyFunction);
         // hidden fields of function object
         f.parent_frame = this.frame;
         f.module = this.module;
         f.func_id = idx;
-        f[SLOT_PREFIX+"name"] = this.module.functions[idx].name;
         f[SLOT_PREFIX+"length"] = this.module.functions[idx].nargs;
+        // MakeConstructor(f)
+        var prototype = Object.create(MyObject);
+        prototype[SLOT_PREFIX+"constructor"] = f;
+        f[SLOT_PREFIX+"prototype"] = prototype;
+        // SetFunctionName
+        f[SLOT_PREFIX+"name"] = this.module.functions[idx].name;
         this.stack.push(f);
     };
     var get_slot = function(obj, name) {

ctiles.js

@@ -15,6 +15,7 @@ add_demo('JS parser', tests.lookup('parse'));
 add_demo('JS compiler', tests.lookup('jcompile'));
 add_demo('Tile renderer', tests.lookup('crender'));
 add_demo('Bytecode table', tests.lookup('bytecode-table'));
+add_demo('Literals map', tests.lookup('literal-map'));
 add_demo('Bytecode compiler', tests.lookup('bcompile'));
 add_demo('Bytecode interpreter', tests.lookup('binterp'));
 add_demo('Standard library', tests.lookup('stdlib'));

literal-map.js

@@ -0,0 +1,52 @@
+// # literal-map.js
+//
+// A simple table of (literal) values
+//
+// Uses a simple hashtable lookup, but uses SameValue for identity
+// (ie, NaN, +0, and -0 are all treated as distinct)
+// Maps any given value into an integer index.
+define(["text!literal-map.js"], function make_literal_map(literal_map_source) {
+
+    var ObjectIs = Object.is || function(a, b) {
+        if (typeof(a)==='number' && typeof(b)==='number') {
+            if (a!==a) { return (b!==b); } // NaN
+            if (a===0) { return (b===0) && (1/a === 1/b); } // +/- 0
+        }
+        return (a===b);
+    };
+
+    var LiteralMap = function(items) {
+        this.map = Object.create(null);
+        this.list = [];
+        if (items!==undefined) {
+            items.forEach(function(v) { this.get(v); }, this);
+        }
+    };
+    // This next line isn't required, but it makes bootstrapping easier.
+    LiteralMap.prototype = { constructor: LiteralMap };
+    LiteralMap.prototype.get = function(val) {
+        var i, pair, key, entries;
+        key = typeof(val) + ':' + val; // very basic hash key
+        entries = this.map[key];
+        if (entries!==undefined) {
+            i = 0;
+            while (i < entries.length) {
+                pair = entries[i];
+                if (ObjectIs(pair[0], val)) { return pair[1]; }
+                i += 1;
+            }
+        } else {
+            entries = [];
+            this.map[key] = entries;
+        }
+        i = this.list.length;
+        this.list[i] = val;
+        entries.push([val, i]);
+        return i;
+    };
+    LiteralMap.__module_name__ = "literal-map";
+    LiteralMap.__module_init__ = make_literal_map;
+    LiteralMap.__module_deps__ = [];
+    LiteralMap.__module_source__ = literal_map_source;
+    return LiteralMap;
+});

nodemain.js

@@ -22,7 +22,7 @@ module.exports = Object.create(null);
 // Things to export.
 ['parse', 'jcompile',
  // Bytecode compiler-interpreter.
- 'bytecode-table', 'bcompile', 'binterp', 'stdlib',
+ 'bytecode-table', 'literal-map', 'bcompile', 'binterp', 'stdlib',
  // `asm.js` project.
  'asm-llvm',
  // FRS-style event system.

tdop.js

@@ -63,6 +63,7 @@ function do_it() {
         tests.lookup("tokenize")+"\n"+
         tests.lookup("parse")+"\n"+
         tests.lookup("bytecode-table")+"\n"+
+        tests.lookup("literal-map")+"\n"+
         tests.lookup("bcompile")+"\n"+
         tests.lookup("binterp")+"\n"+
         top_level_source+"\n"+

test/binterp-tests.js

@@ -33,6 +33,7 @@ var metainterpreter = (function() {
         tests.lookup("tokenize")+"\n"+
         tests.lookup("parse")+"\n"+
         tests.lookup("bytecode-table")+"\n"+
+        tests.lookup("literal-map")+"\n"+
         tests.lookup("bcompile")+"\n"+
         tests.lookup("binterp")+"\n"+
         top_level_source+"\n"+

tests.js

@@ -2,13 +2,15 @@
 define(["text!tests.js", "str-escape",
         /* These modules are just imported to make test cases out of them. */
         "tokenize", "parse", "jcompile", "crender", "bytecode-table",
-        "bcompile", "binterp", "stdlib", "events", "asm-llvm"],
+        "literal-map", "bcompile", "binterp", "stdlib", "events", "asm-llvm"],
        function make_tests(tests_source, str_escape,
                            tokenize, parse, jcompile, crender, bytecode_table,
-                           bcompile, binterp, stdlib, events, asm_llvm) {
+                           LiteralMap, bcompile, binterp, stdlib, events,
+                           asm_llvm) {
     var deps = ["tests_source", "str-escape",
                 "tokenize", "parse", "jcompile", "crender", "bytecode-table",
-                "bcompile", "binterp", "stdlib", "events", "asm-llvm"];
+                "literal-map", "bcompile", "binterp", "stdlib", "events",
+                "asm-llvm"];
     var test=[], i=2/* skip tests_source and str_escape */;
     // The first tests are our own source code, from the module arguments.
     while (i < arguments.length) {

write-lua-bytecode.js

@@ -40,6 +40,7 @@ define(['./parse', './bcompile', './bytecode-table', './top-level', './str-escap
         tests.lookup("tokenize")+"\n"+
         tests.lookup("parse")+"\n"+
         tests.lookup("bytecode-table")+"\n"+
+        tests.lookup("literal-map")+"\n"+
         tests.lookup("bcompile")+"\n"+
         top_level_source+"\n"+
         cfs_source + '\n' +

write-php-bytecode.js

@@ -40,6 +40,7 @@ define(['./parse', './bcompile', './bytecode-table', './top-level', './str-escap
         tests.lookup("tokenize")+"\n"+
         tests.lookup("parse")+"\n"+
         tests.lookup("bytecode-table")+"\n"+
+        tests.lookup("literal-map")+"\n"+
         tests.lookup("bcompile")+"\n"+
         top_level_source+"\n"+
         cfs_source + '\n' +