From 0b76dcf4048533e1adc44ca4b67f3228e9719530 Mon Sep 17 00:00:00 2001 From: Cliff Click Date: Mon, 5 Aug 2024 16:15:27 -0700 Subject: Chapter 13: References Co-authored-by: Thalia Archibald Co-authored-by: Dibyendu Majumdar Co-authored-by: XmiliaH <45106915+XmiliaH@users.noreply.github.com> Co-authored-by: Robert Obkircher --- src/main/java/com/seaofnodes/simple/Parser.java | 59 ++++++++++++++++--------- 1 file changed, 38 insertions(+), 21 deletions(-) (limited to 'src/main/java/com/seaofnodes/simple/Parser.java') diff --git a/src/main/java/com/seaofnodes/simple/Parser.java b/src/main/java/com/seaofnodes/simple/Parser.java index 1a223726..71bd6d02 100644 --- a/src/main/java/com/seaofnodes/simple/Parser.java +++ b/src/main/java/com/seaofnodes/simple/Parser.java @@ -179,7 +179,7 @@ public class Parser { * type IDENTIFIER ; * */ - private Field parseField(String sname) { + private Field parseField() { Type t = type(); if( t==null ) throw errorSyntax("Requires a field type, found '"+_lexer.getAnyNextToken()+"'"); @@ -191,25 +191,26 @@ public class Parser { * Only allowed in top level scope. * Structs cannot be redefined. * - * @return The statement following the struct + * @return null */ private Node parseStruct() { if (_xScopes.size() > 1) throw errorSyntax("struct declarations can only appear in top level scope"); String typeName = requireId(); - if ( TYPES.containsKey(typeName)) throw errorSyntax("struct '" + typeName + "' cannot be redefined"); + Type t = TYPES.get(typeName); + if( t!=null && !(t instanceof TypeStruct ts && ts._fields==null) ) throw errorSyntax("struct '" + typeName + "' cannot be redefined"); ArrayList fields = new ArrayList<>(); require("{"); while (!peek('}') && !_lexer.isEOF()) { - Field field = parseField(typeName); + Field field = parseField(); if (fields.contains(field)) throw errorSyntax("Field '" + field + "' already defined in struct '" + typeName + "'"); fields.add(field); } require("}"); // Build and install the TypeStruct TypeStruct ts = TypeStruct.make(typeName, fields); - TYPES.put(typeName, ts); // Insert the struct name in the collection of all struct names + TYPES.put(typeName, ts); START.addMemProj(ts, _scope); // Insert memory edges - return parseStatement(); + return null; } /** @@ -350,8 +351,8 @@ public class Parser { // Parse the false side _scope = fScope; // Restore scope, then parse else block if any ctrl(ifF.unkeep()); // Ctrl token is now set to ifFalse projection + _scope.upcast(ifF,pred,true); // Up-cast predicate if (matchx("else")) { - _scope.upcast(ifF,pred,true); // Up-cast predicate parseStatement(); fScope = _scope; } @@ -433,24 +434,36 @@ public class Parser { // Auto-widen int to float if( expr._type instanceof TypeInteger && t instanceof TypeFloat ) expr = new ToFloatNode(expr).peephole(); + // Auto-deepen forward ref types + Type e = expr._type; + if( e instanceof TypeMemPtr tmp && tmp._obj._fields==null ) + e = tmp.make_from((TypeStruct)TYPES.get(tmp._obj._name)); // Type is sane - if( !expr._type.isa(t) ) - throw error("Type " + expr._type.str() + " is not of declared type " + t.str()); + if( !e.isa(t) ) + throw error("Type " + e.str() + " is not of declared type " + t.str()); return _scope.update(name,expr); } - // Parse a type-or-null + // Parse a "type id" and return "type" (and re-parse "id" in caller) or + // return null. private Type type() { int old = _lexer._position; String tname = _lexer.matchId(); if( tname==null ) return null; + boolean nullable = match("?"); Type t = TYPES.get(tname); + // Assume a forward-reference type if( t == null ) { - // Not a type; unwind the parse - _lexer._position = old; - return null; + int old2 = _lexer._position; + String id = _lexer.matchId(); + if( id==null ) { + _lexer._position = old; + return null; + } + TYPES.put(tname,t = TypeStruct.make(tname)); + _lexer._position = old2; // Reparse ID in caller } - return t instanceof TypeStruct obj ? TypeMemPtr.make(obj,match("?")) : t; + return t instanceof TypeStruct obj ? TypeMemPtr.make(obj,nullable) : t; } @@ -567,7 +580,8 @@ public class Parser { if( matchx("new") ) { String structName = requireId(); Type t = TYPES.get(structName); - if( t == null || !(t instanceof TypeStruct obj) ) throw errorSyntax("Unknown struct type '" + structName + "'"); + if( !(t instanceof TypeStruct obj) || obj._fields==null ) + throw error("Unknown struct type '" + structName + "'"); return newStruct(obj); } String name = _lexer.matchId(); @@ -584,7 +598,7 @@ public class Parser { Node n = new NewNode(TypeMemPtr.make(obj), ctrl()).peephole().keep(); int alias = START._aliasStarts.get(obj._name); for( Field field : obj._fields ) { - memAlias(alias, new StoreNode(field._fname, alias, ctrl(), memAlias(alias), n, ZERO).peephole()); + memAlias(alias, new StoreNode(field._fname, alias, field._type, ctrl(), memAlias(alias), n, new ConstantNode(field._type.makeInit()).peephole(),true).peephole()); alias++; } return n.unkeep(); @@ -614,7 +628,9 @@ public class Parser { String name = requireId().intern(); if( expr._type == TypeMemPtr.TOP ) throw error("Accessing field '" + name + "' from null"); - int idx = ptr._obj==null ? -1 : ptr._obj.find(name); + if( ptr._obj == null ) throw error("Accessing unknown field '" + name + "' from '" + ptr.str() + "'"); + TypeStruct base = (TypeStruct)TYPES.get(ptr._obj._name); + int idx = base==null ? -1 : base.find(name); if( idx == -1 ) throw error("Accessing unknown field '" + name + "' from '" + ptr.str() + "'"); int alias = START._aliasStarts.get(ptr._obj._name)+idx; @@ -623,13 +639,14 @@ public class Parser { if( peek('=') ) _lexer._position--; else { Node val = parseExpression(); - memAlias(alias, new StoreNode(name, alias, ctrl(), memAlias(alias), expr, val).peephole()); + Type glb = base._fields[idx]._type; + memAlias(alias, new StoreNode(name, alias,glb, ctrl(), memAlias(alias), expr, val, false).peephole()); return expr; // "obj.a = expr" returns the expression while updating memory } } - Type declaredType = ptr._obj._fields[idx]._type; - return parsePostfix(new LoadNode(name, alias, declaredType, memAlias(alias), expr).peephole()); + Type declaredType = base._fields[idx]._type; + return parsePostfix(new LoadNode(name, alias, declaredType.glb(), memAlias(alias), expr).peephole()); } /** @@ -637,7 +654,7 @@ public class Parser { * * 
      *     integerLiteral: [1-9][0-9]* | [0]
-     *     floatLiteral: [1-9][0-9]* | [0]
+     *     floatLiteral: [digits].[digits]?[e [digits]]?
      *
*/ private ConstantNode parseLiteral() { -- cgit v1.2.3