| /* |
| * Copyright (c) 1999, 2016, Oracle and/or its affiliates. All rights reserved. |
| * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. |
| * |
| * This code is free software; you can redistribute it and/or modify it |
| * under the terms of the GNU General Public License version 2 only, as |
| * published by the Free Software Foundation. Oracle designates this |
| * particular file as subject to the "Classpath" exception as provided |
| * by Oracle in the LICENSE file that accompanied this code. |
| * |
| * This code is distributed in the hope that it will be useful, but WITHOUT |
| * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or |
| * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License |
| * version 2 for more details (a copy is included in the LICENSE file that |
| * accompanied this code). |
| * |
| * You should have received a copy of the GNU General Public License version |
| * 2 along with this work; if not, write to the Free Software Foundation, |
| * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. |
| * |
| * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA |
| * or visit www.oracle.com if you need additional information or have any |
| * questions. |
| */ |
| |
| package com.sun.tools.javac.jvm; |
| |
| import com.sun.tools.javac.util.*; |
| import com.sun.tools.javac.util.JCDiagnostic.DiagnosticPosition; |
| import com.sun.tools.javac.util.List; |
| import com.sun.tools.javac.code.*; |
| import com.sun.tools.javac.code.Attribute.TypeCompound; |
| import com.sun.tools.javac.code.Symbol.VarSymbol; |
| import com.sun.tools.javac.comp.*; |
| import com.sun.tools.javac.tree.*; |
| |
| import com.sun.tools.javac.code.Symbol.*; |
| import com.sun.tools.javac.code.Type.*; |
| import com.sun.tools.javac.jvm.Code.*; |
| import com.sun.tools.javac.jvm.Items.*; |
| import com.sun.tools.javac.tree.EndPosTable; |
| import com.sun.tools.javac.tree.JCTree.*; |
| |
| import static com.sun.tools.javac.code.Flags.*; |
| import static com.sun.tools.javac.code.Kinds.Kind.*; |
| import static com.sun.tools.javac.code.TypeTag.*; |
| import static com.sun.tools.javac.jvm.ByteCodes.*; |
| import static com.sun.tools.javac.jvm.CRTFlags.*; |
| import static com.sun.tools.javac.main.Option.*; |
| import static com.sun.tools.javac.tree.JCTree.Tag.*; |
| |
| /** This pass maps flat Java (i.e. without inner classes) to bytecodes. |
| * |
| * <p><b>This is NOT part of any supported API. |
| * If you write code that depends on this, you do so at your own risk. |
| * This code and its internal interfaces are subject to change or |
| * deletion without notice.</b> |
| */ |
| public class Gen extends JCTree.Visitor { |
| protected static final Context.Key<Gen> genKey = new Context.Key<>(); |
| |
| private final Log log; |
| private final Symtab syms; |
| private final Check chk; |
| private final Resolve rs; |
| private final TreeMaker make; |
| private final Names names; |
| private final Target target; |
| private Name accessDollar; |
| private final Types types; |
| private final Lower lower; |
| private final Flow flow; |
| private final Annotate annotate; |
| private final StringConcat concat; |
| |
| /** Format of stackmap tables to be generated. */ |
| private final Code.StackMapFormat stackMap; |
| |
| /** A type that serves as the expected type for all method expressions. |
| */ |
| private final Type methodType; |
| |
| /** |
| * Are we presently traversing a let expression ? Yes if depth != 0 |
| */ |
| private int letExprDepth; |
| |
| public static Gen instance(Context context) { |
| Gen instance = context.get(genKey); |
| if (instance == null) |
| instance = new Gen(context); |
| return instance; |
| } |
| |
| /** Constant pool, reset by genClass. |
| */ |
| private Pool pool; |
| |
| protected Gen(Context context) { |
| context.put(genKey, this); |
| |
| names = Names.instance(context); |
| log = Log.instance(context); |
| syms = Symtab.instance(context); |
| chk = Check.instance(context); |
| rs = Resolve.instance(context); |
| make = TreeMaker.instance(context); |
| target = Target.instance(context); |
| types = Types.instance(context); |
| concat = StringConcat.instance(context); |
| |
| methodType = new MethodType(null, null, null, syms.methodClass); |
| accessDollar = names. |
| fromString("access" + target.syntheticNameChar()); |
| flow = Flow.instance(context); |
| lower = Lower.instance(context); |
| |
| Options options = Options.instance(context); |
| lineDebugInfo = |
| options.isUnset(G_CUSTOM) || |
| options.isSet(G_CUSTOM, "lines"); |
| varDebugInfo = |
| options.isUnset(G_CUSTOM) |
| ? options.isSet(G) |
| : options.isSet(G_CUSTOM, "vars"); |
| genCrt = options.isSet(XJCOV); |
| debugCode = options.isSet("debugcode"); |
| allowBetterNullChecks = target.hasObjects(); |
| pool = new Pool(types); |
| |
| // ignore cldc because we cannot have both stackmap formats |
| this.stackMap = StackMapFormat.JSR202; |
| annotate = Annotate.instance(context); |
| } |
| |
| /** Switches |
| */ |
| private final boolean lineDebugInfo; |
| private final boolean varDebugInfo; |
| private final boolean genCrt; |
| private final boolean debugCode; |
| private final boolean allowBetterNullChecks; |
| |
| /** Code buffer, set by genMethod. |
| */ |
| private Code code; |
| |
| /** Items structure, set by genMethod. |
| */ |
| private Items items; |
| |
| /** Environment for symbol lookup, set by genClass |
| */ |
| private Env<AttrContext> attrEnv; |
| |
| /** The top level tree. |
| */ |
| private JCCompilationUnit toplevel; |
| |
| /** The number of code-gen errors in this class. |
| */ |
| private int nerrs = 0; |
| |
| /** An object containing mappings of syntax trees to their |
| * ending source positions. |
| */ |
| EndPosTable endPosTable; |
| |
| /** Generate code to load an integer constant. |
| * @param n The integer to be loaded. |
| */ |
| void loadIntConst(int n) { |
| items.makeImmediateItem(syms.intType, n).load(); |
| } |
| |
| /** The opcode that loads a zero constant of a given type code. |
| * @param tc The given type code (@see ByteCode). |
| */ |
| public static int zero(int tc) { |
| switch(tc) { |
| case INTcode: case BYTEcode: case SHORTcode: case CHARcode: |
| return iconst_0; |
| case LONGcode: |
| return lconst_0; |
| case FLOATcode: |
| return fconst_0; |
| case DOUBLEcode: |
| return dconst_0; |
| default: |
| throw new AssertionError("zero"); |
| } |
| } |
| |
| /** The opcode that loads a one constant of a given type code. |
| * @param tc The given type code (@see ByteCode). |
| */ |
| public static int one(int tc) { |
| return zero(tc) + 1; |
| } |
| |
| /** Generate code to load -1 of the given type code (either int or long). |
| * @param tc The given type code (@see ByteCode). |
| */ |
| void emitMinusOne(int tc) { |
| if (tc == LONGcode) { |
| items.makeImmediateItem(syms.longType, Long.valueOf(-1)).load(); |
| } else { |
| code.emitop0(iconst_m1); |
| } |
| } |
| |
| /** Construct a symbol to reflect the qualifying type that should |
| * appear in the byte code as per JLS 13.1. |
| * |
| * For {@literal target >= 1.2}: Clone a method with the qualifier as owner (except |
| * for those cases where we need to work around VM bugs). |
| * |
| * For {@literal target <= 1.1}: If qualified variable or method is defined in a |
| * non-accessible class, clone it with the qualifier class as owner. |
| * |
| * @param sym The accessed symbol |
| * @param site The qualifier's type. |
| */ |
| Symbol binaryQualifier(Symbol sym, Type site) { |
| |
| if (site.hasTag(ARRAY)) { |
| if (sym == syms.lengthVar || |
| sym.owner != syms.arrayClass) |
| return sym; |
| // array clone can be qualified by the array type in later targets |
| Symbol qualifier = new ClassSymbol(Flags.PUBLIC, site.tsym.name, |
| site, syms.noSymbol); |
| return sym.clone(qualifier); |
| } |
| |
| if (sym.owner == site.tsym || |
| (sym.flags() & (STATIC | SYNTHETIC)) == (STATIC | SYNTHETIC)) { |
| return sym; |
| } |
| |
| // leave alone methods inherited from Object |
| // JLS 13.1. |
| if (sym.owner == syms.objectType.tsym) |
| return sym; |
| |
| return sym.clone(site.tsym); |
| } |
| |
| /** Insert a reference to given type in the constant pool, |
| * checking for an array with too many dimensions; |
| * return the reference's index. |
| * @param type The type for which a reference is inserted. |
| */ |
| int makeRef(DiagnosticPosition pos, Type type) { |
| checkDimension(pos, type); |
| if (type.isAnnotated()) { |
| return pool.put((Object)type); |
| } else { |
| return pool.put(type.hasTag(CLASS) ? (Object)type.tsym : (Object)type); |
| } |
| } |
| |
| /** Check if the given type is an array with too many dimensions. |
| */ |
| private void checkDimension(DiagnosticPosition pos, Type t) { |
| switch (t.getTag()) { |
| case METHOD: |
| checkDimension(pos, t.getReturnType()); |
| for (List<Type> args = t.getParameterTypes(); args.nonEmpty(); args = args.tail) |
| checkDimension(pos, args.head); |
| break; |
| case ARRAY: |
| if (types.dimensions(t) > ClassFile.MAX_DIMENSIONS) { |
| log.error(pos, "limit.dimensions"); |
| nerrs++; |
| } |
| break; |
| default: |
| break; |
| } |
| } |
| |
| /** Create a tempory variable. |
| * @param type The variable's type. |
| */ |
| LocalItem makeTemp(Type type) { |
| VarSymbol v = new VarSymbol(Flags.SYNTHETIC, |
| names.empty, |
| type, |
| env.enclMethod.sym); |
| code.newLocal(v); |
| return items.makeLocalItem(v); |
| } |
| |
| /** Generate code to call a non-private method or constructor. |
| * @param pos Position to be used for error reporting. |
| * @param site The type of which the method is a member. |
| * @param name The method's name. |
| * @param argtypes The method's argument types. |
| * @param isStatic A flag that indicates whether we call a |
| * static or instance method. |
| */ |
| void callMethod(DiagnosticPosition pos, |
| Type site, Name name, List<Type> argtypes, |
| boolean isStatic) { |
| Symbol msym = rs. |
| resolveInternalMethod(pos, attrEnv, site, name, argtypes, null); |
| if (isStatic) items.makeStaticItem(msym).invoke(); |
| else items.makeMemberItem(msym, name == names.init).invoke(); |
| } |
| |
| /** Is the given method definition an access method |
| * resulting from a qualified super? This is signified by an odd |
| * access code. |
| */ |
| private boolean isAccessSuper(JCMethodDecl enclMethod) { |
| return |
| (enclMethod.mods.flags & SYNTHETIC) != 0 && |
| isOddAccessName(enclMethod.name); |
| } |
| |
| /** Does given name start with "access$" and end in an odd digit? |
| */ |
| private boolean isOddAccessName(Name name) { |
| return |
| name.startsWith(accessDollar) && |
| (name.getByteAt(name.getByteLength() - 1) & 1) == 1; |
| } |
| |
| /* ************************************************************************ |
| * Non-local exits |
| *************************************************************************/ |
| |
| /** Generate code to invoke the finalizer associated with given |
| * environment. |
| * Any calls to finalizers are appended to the environments `cont' chain. |
| * Mark beginning of gap in catch all range for finalizer. |
| */ |
| void genFinalizer(Env<GenContext> env) { |
| if (code.isAlive() && env.info.finalize != null) |
| env.info.finalize.gen(); |
| } |
| |
| /** Generate code to call all finalizers of structures aborted by |
| * a non-local |
| * exit. Return target environment of the non-local exit. |
| * @param target The tree representing the structure that's aborted |
| * @param env The environment current at the non-local exit. |
| */ |
| Env<GenContext> unwind(JCTree target, Env<GenContext> env) { |
| Env<GenContext> env1 = env; |
| while (true) { |
| genFinalizer(env1); |
| if (env1.tree == target) break; |
| env1 = env1.next; |
| } |
| return env1; |
| } |
| |
| /** Mark end of gap in catch-all range for finalizer. |
| * @param env the environment which might contain the finalizer |
| * (if it does, env.info.gaps != null). |
| */ |
| void endFinalizerGap(Env<GenContext> env) { |
| if (env.info.gaps != null && env.info.gaps.length() % 2 == 1) |
| env.info.gaps.append(code.curCP()); |
| } |
| |
| /** Mark end of all gaps in catch-all ranges for finalizers of environments |
| * lying between, and including to two environments. |
| * @param from the most deeply nested environment to mark |
| * @param to the least deeply nested environment to mark |
| */ |
| void endFinalizerGaps(Env<GenContext> from, Env<GenContext> to) { |
| Env<GenContext> last = null; |
| while (last != to) { |
| endFinalizerGap(from); |
| last = from; |
| from = from.next; |
| } |
| } |
| |
| /** Do any of the structures aborted by a non-local exit have |
| * finalizers that require an empty stack? |
| * @param target The tree representing the structure that's aborted |
| * @param env The environment current at the non-local exit. |
| */ |
| boolean hasFinally(JCTree target, Env<GenContext> env) { |
| while (env.tree != target) { |
| if (env.tree.hasTag(TRY) && env.info.finalize.hasFinalizer()) |
| return true; |
| env = env.next; |
| } |
| return false; |
| } |
| |
| /* ************************************************************************ |
| * Normalizing class-members. |
| *************************************************************************/ |
| |
| /** Distribute member initializer code into constructors and {@code <clinit>} |
| * method. |
| * @param defs The list of class member declarations. |
| * @param c The enclosing class. |
| */ |
| List<JCTree> normalizeDefs(List<JCTree> defs, ClassSymbol c) { |
| ListBuffer<JCStatement> initCode = new ListBuffer<>(); |
| ListBuffer<Attribute.TypeCompound> initTAs = new ListBuffer<>(); |
| ListBuffer<JCStatement> clinitCode = new ListBuffer<>(); |
| ListBuffer<Attribute.TypeCompound> clinitTAs = new ListBuffer<>(); |
| ListBuffer<JCTree> methodDefs = new ListBuffer<>(); |
| // Sort definitions into three listbuffers: |
| // - initCode for instance initializers |
| // - clinitCode for class initializers |
| // - methodDefs for method definitions |
| for (List<JCTree> l = defs; l.nonEmpty(); l = l.tail) { |
| JCTree def = l.head; |
| switch (def.getTag()) { |
| case BLOCK: |
| JCBlock block = (JCBlock)def; |
| if ((block.flags & STATIC) != 0) |
| clinitCode.append(block); |
| else if ((block.flags & SYNTHETIC) == 0) |
| initCode.append(block); |
| break; |
| case METHODDEF: |
| methodDefs.append(def); |
| break; |
| case VARDEF: |
| JCVariableDecl vdef = (JCVariableDecl) def; |
| VarSymbol sym = vdef.sym; |
| checkDimension(vdef.pos(), sym.type); |
| if (vdef.init != null) { |
| if ((sym.flags() & STATIC) == 0) { |
| // Always initialize instance variables. |
| JCStatement init = make.at(vdef.pos()). |
| Assignment(sym, vdef.init); |
| initCode.append(init); |
| endPosTable.replaceTree(vdef, init); |
| initTAs.addAll(getAndRemoveNonFieldTAs(sym)); |
| } else if (sym.getConstValue() == null) { |
| // Initialize class (static) variables only if |
| // they are not compile-time constants. |
| JCStatement init = make.at(vdef.pos). |
| Assignment(sym, vdef.init); |
| clinitCode.append(init); |
| endPosTable.replaceTree(vdef, init); |
| clinitTAs.addAll(getAndRemoveNonFieldTAs(sym)); |
| } else { |
| checkStringConstant(vdef.init.pos(), sym.getConstValue()); |
| /* if the init contains a reference to an external class, add it to the |
| * constant's pool |
| */ |
| vdef.init.accept(classReferenceVisitor); |
| } |
| } |
| break; |
| default: |
| Assert.error(); |
| } |
| } |
| // Insert any instance initializers into all constructors. |
| if (initCode.length() != 0) { |
| List<JCStatement> inits = initCode.toList(); |
| initTAs.addAll(c.getInitTypeAttributes()); |
| List<Attribute.TypeCompound> initTAlist = initTAs.toList(); |
| for (JCTree t : methodDefs) { |
| normalizeMethod((JCMethodDecl)t, inits, initTAlist); |
| } |
| } |
| // If there are class initializers, create a <clinit> method |
| // that contains them as its body. |
| if (clinitCode.length() != 0) { |
| MethodSymbol clinit = new MethodSymbol( |
| STATIC | (c.flags() & STRICTFP), |
| names.clinit, |
| new MethodType( |
| List.<Type>nil(), syms.voidType, |
| List.<Type>nil(), syms.methodClass), |
| c); |
| c.members().enter(clinit); |
| List<JCStatement> clinitStats = clinitCode.toList(); |
| JCBlock block = make.at(clinitStats.head.pos()).Block(0, clinitStats); |
| block.endpos = TreeInfo.endPos(clinitStats.last()); |
| methodDefs.append(make.MethodDef(clinit, block)); |
| |
| if (!clinitTAs.isEmpty()) |
| clinit.appendUniqueTypeAttributes(clinitTAs.toList()); |
| if (!c.getClassInitTypeAttributes().isEmpty()) |
| clinit.appendUniqueTypeAttributes(c.getClassInitTypeAttributes()); |
| } |
| // Return all method definitions. |
| return methodDefs.toList(); |
| } |
| |
| private List<Attribute.TypeCompound> getAndRemoveNonFieldTAs(VarSymbol sym) { |
| List<TypeCompound> tas = sym.getRawTypeAttributes(); |
| ListBuffer<Attribute.TypeCompound> fieldTAs = new ListBuffer<>(); |
| ListBuffer<Attribute.TypeCompound> nonfieldTAs = new ListBuffer<>(); |
| for (TypeCompound ta : tas) { |
| Assert.check(ta.getPosition().type != TargetType.UNKNOWN); |
| if (ta.getPosition().type == TargetType.FIELD) { |
| fieldTAs.add(ta); |
| } else { |
| nonfieldTAs.add(ta); |
| } |
| } |
| sym.setTypeAttributes(fieldTAs.toList()); |
| return nonfieldTAs.toList(); |
| } |
| |
| /** Check a constant value and report if it is a string that is |
| * too large. |
| */ |
| private void checkStringConstant(DiagnosticPosition pos, Object constValue) { |
| if (nerrs != 0 || // only complain about a long string once |
| constValue == null || |
| !(constValue instanceof String) || |
| ((String)constValue).length() < Pool.MAX_STRING_LENGTH) |
| return; |
| log.error(pos, "limit.string"); |
| nerrs++; |
| } |
| |
| /** Insert instance initializer code into initial constructor. |
| * @param md The tree potentially representing a |
| * constructor's definition. |
| * @param initCode The list of instance initializer statements. |
| * @param initTAs Type annotations from the initializer expression. |
| */ |
| void normalizeMethod(JCMethodDecl md, List<JCStatement> initCode, List<TypeCompound> initTAs) { |
| if (md.name == names.init && TreeInfo.isInitialConstructor(md)) { |
| // We are seeing a constructor that does not call another |
| // constructor of the same class. |
| List<JCStatement> stats = md.body.stats; |
| ListBuffer<JCStatement> newstats = new ListBuffer<>(); |
| |
| if (stats.nonEmpty()) { |
| // Copy initializers of synthetic variables generated in |
| // the translation of inner classes. |
| while (TreeInfo.isSyntheticInit(stats.head)) { |
| newstats.append(stats.head); |
| stats = stats.tail; |
| } |
| // Copy superclass constructor call |
| newstats.append(stats.head); |
| stats = stats.tail; |
| // Copy remaining synthetic initializers. |
| while (stats.nonEmpty() && |
| TreeInfo.isSyntheticInit(stats.head)) { |
| newstats.append(stats.head); |
| stats = stats.tail; |
| } |
| // Now insert the initializer code. |
| newstats.appendList(initCode); |
| // And copy all remaining statements. |
| while (stats.nonEmpty()) { |
| newstats.append(stats.head); |
| stats = stats.tail; |
| } |
| } |
| md.body.stats = newstats.toList(); |
| if (md.body.endpos == Position.NOPOS) |
| md.body.endpos = TreeInfo.endPos(md.body.stats.last()); |
| |
| md.sym.appendUniqueTypeAttributes(initTAs); |
| } |
| } |
| |
| /* ************************************************************************ |
| * Traversal methods |
| *************************************************************************/ |
| |
| /** Visitor argument: The current environment. |
| */ |
| Env<GenContext> env; |
| |
| /** Visitor argument: The expected type (prototype). |
| */ |
| Type pt; |
| |
| /** Visitor result: The item representing the computed value. |
| */ |
| Item result; |
| |
| /** Visitor method: generate code for a definition, catching and reporting |
| * any completion failures. |
| * @param tree The definition to be visited. |
| * @param env The environment current at the definition. |
| */ |
| public void genDef(JCTree tree, Env<GenContext> env) { |
| Env<GenContext> prevEnv = this.env; |
| try { |
| this.env = env; |
| tree.accept(this); |
| } catch (CompletionFailure ex) { |
| chk.completionError(tree.pos(), ex); |
| } finally { |
| this.env = prevEnv; |
| } |
| } |
| |
| /** Derived visitor method: check whether CharacterRangeTable |
| * should be emitted, if so, put a new entry into CRTable |
| * and call method to generate bytecode. |
| * If not, just call method to generate bytecode. |
| * @see #genStat(JCTree, Env) |
| * |
| * @param tree The tree to be visited. |
| * @param env The environment to use. |
| * @param crtFlags The CharacterRangeTable flags |
| * indicating type of the entry. |
| */ |
| public void genStat(JCTree tree, Env<GenContext> env, int crtFlags) { |
| if (!genCrt) { |
| genStat(tree, env); |
| return; |
| } |
| int startpc = code.curCP(); |
| genStat(tree, env); |
| if (tree.hasTag(Tag.BLOCK)) crtFlags |= CRT_BLOCK; |
| code.crt.put(tree, crtFlags, startpc, code.curCP()); |
| } |
| |
| /** Derived visitor method: generate code for a statement. |
| */ |
| public void genStat(JCTree tree, Env<GenContext> env) { |
| if (code.isAlive()) { |
| code.statBegin(tree.pos); |
| genDef(tree, env); |
| } else if (env.info.isSwitch && tree.hasTag(VARDEF)) { |
| // variables whose declarations are in a switch |
| // can be used even if the decl is unreachable. |
| code.newLocal(((JCVariableDecl) tree).sym); |
| } |
| } |
| |
| /** Derived visitor method: check whether CharacterRangeTable |
| * should be emitted, if so, put a new entry into CRTable |
| * and call method to generate bytecode. |
| * If not, just call method to generate bytecode. |
| * @see #genStats(List, Env) |
| * |
| * @param trees The list of trees to be visited. |
| * @param env The environment to use. |
| * @param crtFlags The CharacterRangeTable flags |
| * indicating type of the entry. |
| */ |
| public void genStats(List<JCStatement> trees, Env<GenContext> env, int crtFlags) { |
| if (!genCrt) { |
| genStats(trees, env); |
| return; |
| } |
| if (trees.length() == 1) { // mark one statement with the flags |
| genStat(trees.head, env, crtFlags | CRT_STATEMENT); |
| } else { |
| int startpc = code.curCP(); |
| genStats(trees, env); |
| code.crt.put(trees, crtFlags, startpc, code.curCP()); |
| } |
| } |
| |
| /** Derived visitor method: generate code for a list of statements. |
| */ |
| public void genStats(List<? extends JCTree> trees, Env<GenContext> env) { |
| for (List<? extends JCTree> l = trees; l.nonEmpty(); l = l.tail) |
| genStat(l.head, env, CRT_STATEMENT); |
| } |
| |
| /** Derived visitor method: check whether CharacterRangeTable |
| * should be emitted, if so, put a new entry into CRTable |
| * and call method to generate bytecode. |
| * If not, just call method to generate bytecode. |
| * @see #genCond(JCTree,boolean) |
| * |
| * @param tree The tree to be visited. |
| * @param crtFlags The CharacterRangeTable flags |
| * indicating type of the entry. |
| */ |
| public CondItem genCond(JCTree tree, int crtFlags) { |
| if (!genCrt) return genCond(tree, false); |
| int startpc = code.curCP(); |
| CondItem item = genCond(tree, (crtFlags & CRT_FLOW_CONTROLLER) != 0); |
| code.crt.put(tree, crtFlags, startpc, code.curCP()); |
| return item; |
| } |
| |
| /** Derived visitor method: generate code for a boolean |
| * expression in a control-flow context. |
| * @param _tree The expression to be visited. |
| * @param markBranches The flag to indicate that the condition is |
| * a flow controller so produced conditions |
| * should contain a proper tree to generate |
| * CharacterRangeTable branches for them. |
| */ |
| public CondItem genCond(JCTree _tree, boolean markBranches) { |
| JCTree inner_tree = TreeInfo.skipParens(_tree); |
| if (inner_tree.hasTag(CONDEXPR)) { |
| JCConditional tree = (JCConditional)inner_tree; |
| CondItem cond = genCond(tree.cond, CRT_FLOW_CONTROLLER); |
| if (cond.isTrue()) { |
| code.resolve(cond.trueJumps); |
| CondItem result = genCond(tree.truepart, CRT_FLOW_TARGET); |
| if (markBranches) result.tree = tree.truepart; |
| return result; |
| } |
| if (cond.isFalse()) { |
| code.resolve(cond.falseJumps); |
| CondItem result = genCond(tree.falsepart, CRT_FLOW_TARGET); |
| if (markBranches) result.tree = tree.falsepart; |
| return result; |
| } |
| Chain secondJumps = cond.jumpFalse(); |
| code.resolve(cond.trueJumps); |
| CondItem first = genCond(tree.truepart, CRT_FLOW_TARGET); |
| if (markBranches) first.tree = tree.truepart; |
| Chain falseJumps = first.jumpFalse(); |
| code.resolve(first.trueJumps); |
| Chain trueJumps = code.branch(goto_); |
| code.resolve(secondJumps); |
| CondItem second = genCond(tree.falsepart, CRT_FLOW_TARGET); |
| CondItem result = items.makeCondItem(second.opcode, |
| Code.mergeChains(trueJumps, second.trueJumps), |
| Code.mergeChains(falseJumps, second.falseJumps)); |
| if (markBranches) result.tree = tree.falsepart; |
| return result; |
| } else { |
| CondItem result = genExpr(_tree, syms.booleanType).mkCond(); |
| if (markBranches) result.tree = _tree; |
| return result; |
| } |
| } |
| |
| public Code getCode() { |
| return code; |
| } |
| |
| public Items getItems() { |
| return items; |
| } |
| |
| public Env<AttrContext> getAttrEnv() { |
| return attrEnv; |
| } |
| |
| /** Visitor class for expressions which might be constant expressions. |
| * This class is a subset of TreeScanner. Intended to visit trees pruned by |
| * Lower as long as constant expressions looking for references to any |
| * ClassSymbol. Any such reference will be added to the constant pool so |
| * automated tools can detect class dependencies better. |
| */ |
| class ClassReferenceVisitor extends JCTree.Visitor { |
| |
| @Override |
| public void visitTree(JCTree tree) {} |
| |
| @Override |
| public void visitBinary(JCBinary tree) { |
| tree.lhs.accept(this); |
| tree.rhs.accept(this); |
| } |
| |
| @Override |
| public void visitSelect(JCFieldAccess tree) { |
| if (tree.selected.type.hasTag(CLASS)) { |
| makeRef(tree.selected.pos(), tree.selected.type); |
| } |
| } |
| |
| @Override |
| public void visitIdent(JCIdent tree) { |
| if (tree.sym.owner instanceof ClassSymbol) { |
| pool.put(tree.sym.owner); |
| } |
| } |
| |
| @Override |
| public void visitConditional(JCConditional tree) { |
| tree.cond.accept(this); |
| tree.truepart.accept(this); |
| tree.falsepart.accept(this); |
| } |
| |
| @Override |
| public void visitUnary(JCUnary tree) { |
| tree.arg.accept(this); |
| } |
| |
| @Override |
| public void visitParens(JCParens tree) { |
| tree.expr.accept(this); |
| } |
| |
| @Override |
| public void visitTypeCast(JCTypeCast tree) { |
| tree.expr.accept(this); |
| } |
| } |
| |
| private ClassReferenceVisitor classReferenceVisitor = new ClassReferenceVisitor(); |
| |
| /** Visitor method: generate code for an expression, catching and reporting |
| * any completion failures. |
| * @param tree The expression to be visited. |
| * @param pt The expression's expected type (proto-type). |
| */ |
| public Item genExpr(JCTree tree, Type pt) { |
| Type prevPt = this.pt; |
| try { |
| if (tree.type.constValue() != null) { |
| // Short circuit any expressions which are constants |
| tree.accept(classReferenceVisitor); |
| checkStringConstant(tree.pos(), tree.type.constValue()); |
| result = items.makeImmediateItem(tree.type, tree.type.constValue()); |
| } else { |
| this.pt = pt; |
| tree.accept(this); |
| } |
| return result.coerce(pt); |
| } catch (CompletionFailure ex) { |
| chk.completionError(tree.pos(), ex); |
| code.state.stacksize = 1; |
| return items.makeStackItem(pt); |
| } finally { |
| this.pt = prevPt; |
| } |
| } |
| |
| /** Derived visitor method: generate code for a list of method arguments. |
| * @param trees The argument expressions to be visited. |
| * @param pts The expression's expected types (i.e. the formal parameter |
| * types of the invoked method). |
| */ |
| public void genArgs(List<JCExpression> trees, List<Type> pts) { |
| for (List<JCExpression> l = trees; l.nonEmpty(); l = l.tail) { |
| genExpr(l.head, pts.head).load(); |
| pts = pts.tail; |
| } |
| // require lists be of same length |
| Assert.check(pts.isEmpty()); |
| } |
| |
| /* ************************************************************************ |
| * Visitor methods for statements and definitions |
| *************************************************************************/ |
| |
| /** Thrown when the byte code size exceeds limit. |
| */ |
| public static class CodeSizeOverflow extends RuntimeException { |
| private static final long serialVersionUID = 0; |
| public CodeSizeOverflow() {} |
| } |
| |
| public void visitMethodDef(JCMethodDecl tree) { |
| // Create a new local environment that points pack at method |
| // definition. |
| Env<GenContext> localEnv = env.dup(tree); |
| localEnv.enclMethod = tree; |
| // The expected type of every return statement in this method |
| // is the method's return type. |
| this.pt = tree.sym.erasure(types).getReturnType(); |
| |
| checkDimension(tree.pos(), tree.sym.erasure(types)); |
| genMethod(tree, localEnv, false); |
| } |
| //where |
| /** Generate code for a method. |
| * @param tree The tree representing the method definition. |
| * @param env The environment current for the method body. |
| * @param fatcode A flag that indicates whether all jumps are |
| * within 32K. We first invoke this method under |
| * the assumption that fatcode == false, i.e. all |
| * jumps are within 32K. If this fails, fatcode |
| * is set to true and we try again. |
| */ |
| void genMethod(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) { |
| MethodSymbol meth = tree.sym; |
| int extras = 0; |
| // Count up extra parameters |
| if (meth.isConstructor()) { |
| extras++; |
| if (meth.enclClass().isInner() && |
| !meth.enclClass().isStatic()) { |
| extras++; |
| } |
| } else if ((tree.mods.flags & STATIC) == 0) { |
| extras++; |
| } |
| // System.err.println("Generating " + meth + " in " + meth.owner); //DEBUG |
| if (Code.width(types.erasure(env.enclMethod.sym.type).getParameterTypes()) + extras > |
| ClassFile.MAX_PARAMETERS) { |
| log.error(tree.pos(), "limit.parameters"); |
| nerrs++; |
| } |
| |
| else if (tree.body != null) { |
| // Create a new code structure and initialize it. |
| int startpcCrt = initCode(tree, env, fatcode); |
| |
| try { |
| genStat(tree.body, env); |
| } catch (CodeSizeOverflow e) { |
| // Failed due to code limit, try again with jsr/ret |
| startpcCrt = initCode(tree, env, fatcode); |
| genStat(tree.body, env); |
| } |
| |
| if (code.state.stacksize != 0) { |
| log.error(tree.body.pos(), "stack.sim.error", tree); |
| throw new AssertionError(); |
| } |
| |
| // If last statement could complete normally, insert a |
| // return at the end. |
| if (code.isAlive()) { |
| code.statBegin(TreeInfo.endPos(tree.body)); |
| if (env.enclMethod == null || |
| env.enclMethod.sym.type.getReturnType().hasTag(VOID)) { |
| code.emitop0(return_); |
| } else { |
| // sometime dead code seems alive (4415991); |
| // generate a small loop instead |
| int startpc = code.entryPoint(); |
| CondItem c = items.makeCondItem(goto_); |
| code.resolve(c.jumpTrue(), startpc); |
| } |
| } |
| if (genCrt) |
| code.crt.put(tree.body, |
| CRT_BLOCK, |
| startpcCrt, |
| code.curCP()); |
| |
| code.endScopes(0); |
| |
| // If we exceeded limits, panic |
| if (code.checkLimits(tree.pos(), log)) { |
| nerrs++; |
| return; |
| } |
| |
| // If we generated short code but got a long jump, do it again |
| // with fatCode = true. |
| if (!fatcode && code.fatcode) genMethod(tree, env, true); |
| |
| // Clean up |
| if(stackMap == StackMapFormat.JSR202) { |
| code.lastFrame = null; |
| code.frameBeforeLast = null; |
| } |
| |
| // Compress exception table |
| code.compressCatchTable(); |
| |
| // Fill in type annotation positions for exception parameters |
| code.fillExceptionParameterPositions(); |
| } |
| } |
| |
| private int initCode(JCMethodDecl tree, Env<GenContext> env, boolean fatcode) { |
| MethodSymbol meth = tree.sym; |
| |
| // Create a new code structure. |
| meth.code = code = new Code(meth, |
| fatcode, |
| lineDebugInfo ? toplevel.lineMap : null, |
| varDebugInfo, |
| stackMap, |
| debugCode, |
| genCrt ? new CRTable(tree, env.toplevel.endPositions) |
| : null, |
| syms, |
| types, |
| pool); |
| items = new Items(pool, code, syms, types); |
| if (code.debugCode) { |
| System.err.println(meth + " for body " + tree); |
| } |
| |
| // If method is not static, create a new local variable address |
| // for `this'. |
| if ((tree.mods.flags & STATIC) == 0) { |
| Type selfType = meth.owner.type; |
| if (meth.isConstructor() && selfType != syms.objectType) |
| selfType = UninitializedType.uninitializedThis(selfType); |
| code.setDefined( |
| code.newLocal( |
| new VarSymbol(FINAL, names._this, selfType, meth.owner))); |
| } |
| |
| // Mark all parameters as defined from the beginning of |
| // the method. |
| for (List<JCVariableDecl> l = tree.params; l.nonEmpty(); l = l.tail) { |
| checkDimension(l.head.pos(), l.head.sym.type); |
| code.setDefined(code.newLocal(l.head.sym)); |
| } |
| |
| // Get ready to generate code for method body. |
| int startpcCrt = genCrt ? code.curCP() : 0; |
| code.entryPoint(); |
| |
| // Suppress initial stackmap |
| code.pendingStackMap = false; |
| |
| return startpcCrt; |
| } |
| |
| public void visitVarDef(JCVariableDecl tree) { |
| VarSymbol v = tree.sym; |
| code.newLocal(v); |
| if (tree.init != null) { |
| checkStringConstant(tree.init.pos(), v.getConstValue()); |
| if (v.getConstValue() == null || varDebugInfo) { |
| Assert.check(letExprDepth != 0 || code.state.stacksize == 0); |
| genExpr(tree.init, v.erasure(types)).load(); |
| items.makeLocalItem(v).store(); |
| Assert.check(letExprDepth != 0 || code.state.stacksize == 0); |
| } |
| } |
| checkDimension(tree.pos(), v.type); |
| } |
| |
| public void visitSkip(JCSkip tree) { |
| } |
| |
| public void visitBlock(JCBlock tree) { |
| int limit = code.nextreg; |
| Env<GenContext> localEnv = env.dup(tree, new GenContext()); |
| genStats(tree.stats, localEnv); |
| // End the scope of all block-local variables in variable info. |
| if (!env.tree.hasTag(METHODDEF)) { |
| code.statBegin(tree.endpos); |
| code.endScopes(limit); |
| code.pendingStatPos = Position.NOPOS; |
| } |
| } |
| |
| public void visitDoLoop(JCDoWhileLoop tree) { |
| genLoop(tree, tree.body, tree.cond, List.<JCExpressionStatement>nil(), false); |
| } |
| |
| public void visitWhileLoop(JCWhileLoop tree) { |
| genLoop(tree, tree.body, tree.cond, List.<JCExpressionStatement>nil(), true); |
| } |
| |
| public void visitForLoop(JCForLoop tree) { |
| int limit = code.nextreg; |
| genStats(tree.init, env); |
| genLoop(tree, tree.body, tree.cond, tree.step, true); |
| code.endScopes(limit); |
| } |
| //where |
| /** Generate code for a loop. |
| * @param loop The tree representing the loop. |
| * @param body The loop's body. |
| * @param cond The loop's controling condition. |
| * @param step "Step" statements to be inserted at end of |
| * each iteration. |
| * @param testFirst True if the loop test belongs before the body. |
| */ |
| private void genLoop(JCStatement loop, |
| JCStatement body, |
| JCExpression cond, |
| List<JCExpressionStatement> step, |
| boolean testFirst) { |
| Env<GenContext> loopEnv = env.dup(loop, new GenContext()); |
| int startpc = code.entryPoint(); |
| if (testFirst) { //while or for loop |
| CondItem c; |
| if (cond != null) { |
| code.statBegin(cond.pos); |
| Assert.check(code.state.stacksize == 0); |
| c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER); |
| } else { |
| c = items.makeCondItem(goto_); |
| } |
| Chain loopDone = c.jumpFalse(); |
| code.resolve(c.trueJumps); |
| Assert.check(code.state.stacksize == 0); |
| genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET); |
| code.resolve(loopEnv.info.cont); |
| genStats(step, loopEnv); |
| code.resolve(code.branch(goto_), startpc); |
| code.resolve(loopDone); |
| } else { |
| genStat(body, loopEnv, CRT_STATEMENT | CRT_FLOW_TARGET); |
| code.resolve(loopEnv.info.cont); |
| genStats(step, loopEnv); |
| CondItem c; |
| if (cond != null) { |
| code.statBegin(cond.pos); |
| Assert.check(code.state.stacksize == 0); |
| c = genCond(TreeInfo.skipParens(cond), CRT_FLOW_CONTROLLER); |
| } else { |
| c = items.makeCondItem(goto_); |
| } |
| code.resolve(c.jumpTrue(), startpc); |
| Assert.check(code.state.stacksize == 0); |
| code.resolve(c.falseJumps); |
| } |
| Chain exit = loopEnv.info.exit; |
| if (exit != null) { |
| code.resolve(exit); |
| exit.state.defined.excludeFrom(code.nextreg); |
| } |
| } |
| |
| public void visitForeachLoop(JCEnhancedForLoop tree) { |
| throw new AssertionError(); // should have been removed by Lower. |
| } |
| |
| public void visitLabelled(JCLabeledStatement tree) { |
| Env<GenContext> localEnv = env.dup(tree, new GenContext()); |
| genStat(tree.body, localEnv, CRT_STATEMENT); |
| Chain exit = localEnv.info.exit; |
| if (exit != null) { |
| code.resolve(exit); |
| exit.state.defined.excludeFrom(code.nextreg); |
| } |
| } |
| |
| public void visitSwitch(JCSwitch tree) { |
| int limit = code.nextreg; |
| Assert.check(!tree.selector.type.hasTag(CLASS)); |
| int startpcCrt = genCrt ? code.curCP() : 0; |
| Assert.check(code.state.stacksize == 0); |
| Item sel = genExpr(tree.selector, syms.intType); |
| List<JCCase> cases = tree.cases; |
| if (cases.isEmpty()) { |
| // We are seeing: switch <sel> {} |
| sel.load().drop(); |
| if (genCrt) |
| code.crt.put(TreeInfo.skipParens(tree.selector), |
| CRT_FLOW_CONTROLLER, startpcCrt, code.curCP()); |
| } else { |
| // We are seeing a nonempty switch. |
| sel.load(); |
| if (genCrt) |
| code.crt.put(TreeInfo.skipParens(tree.selector), |
| CRT_FLOW_CONTROLLER, startpcCrt, code.curCP()); |
| Env<GenContext> switchEnv = env.dup(tree, new GenContext()); |
| switchEnv.info.isSwitch = true; |
| |
| // Compute number of labels and minimum and maximum label values. |
| // For each case, store its label in an array. |
| int lo = Integer.MAX_VALUE; // minimum label. |
| int hi = Integer.MIN_VALUE; // maximum label. |
| int nlabels = 0; // number of labels. |
| |
| int[] labels = new int[cases.length()]; // the label array. |
| int defaultIndex = -1; // the index of the default clause. |
| |
| List<JCCase> l = cases; |
| for (int i = 0; i < labels.length; i++) { |
| if (l.head.pat != null) { |
| int val = ((Number)l.head.pat.type.constValue()).intValue(); |
| labels[i] = val; |
| if (val < lo) lo = val; |
| if (hi < val) hi = val; |
| nlabels++; |
| } else { |
| Assert.check(defaultIndex == -1); |
| defaultIndex = i; |
| } |
| l = l.tail; |
| } |
| |
| // Determine whether to issue a tableswitch or a lookupswitch |
| // instruction. |
| long table_space_cost = 4 + ((long) hi - lo + 1); // words |
| long table_time_cost = 3; // comparisons |
| long lookup_space_cost = 3 + 2 * (long) nlabels; |
| long lookup_time_cost = nlabels; |
| int opcode = |
| nlabels > 0 && |
| table_space_cost + 3 * table_time_cost <= |
| lookup_space_cost + 3 * lookup_time_cost |
| ? |
| tableswitch : lookupswitch; |
| |
| int startpc = code.curCP(); // the position of the selector operation |
| code.emitop0(opcode); |
| code.align(4); |
| int tableBase = code.curCP(); // the start of the jump table |
| int[] offsets = null; // a table of offsets for a lookupswitch |
| code.emit4(-1); // leave space for default offset |
| if (opcode == tableswitch) { |
| code.emit4(lo); // minimum label |
| code.emit4(hi); // maximum label |
| for (long i = lo; i <= hi; i++) { // leave space for jump table |
| code.emit4(-1); |
| } |
| } else { |
| code.emit4(nlabels); // number of labels |
| for (int i = 0; i < nlabels; i++) { |
| code.emit4(-1); code.emit4(-1); // leave space for lookup table |
| } |
| offsets = new int[labels.length]; |
| } |
| Code.State stateSwitch = code.state.dup(); |
| code.markDead(); |
| |
| // For each case do: |
| l = cases; |
| for (int i = 0; i < labels.length; i++) { |
| JCCase c = l.head; |
| l = l.tail; |
| |
| int pc = code.entryPoint(stateSwitch); |
| // Insert offset directly into code or else into the |
| // offsets table. |
| if (i != defaultIndex) { |
| if (opcode == tableswitch) { |
| code.put4( |
| tableBase + 4 * (labels[i] - lo + 3), |
| pc - startpc); |
| } else { |
| offsets[i] = pc - startpc; |
| } |
| } else { |
| code.put4(tableBase, pc - startpc); |
| } |
| |
| // Generate code for the statements in this case. |
| genStats(c.stats, switchEnv, CRT_FLOW_TARGET); |
| } |
| |
| // Resolve all breaks. |
| Chain exit = switchEnv.info.exit; |
| if (exit != null) { |
| code.resolve(exit); |
| exit.state.defined.excludeFrom(code.nextreg); |
| } |
| |
| // If we have not set the default offset, we do so now. |
| if (code.get4(tableBase) == -1) { |
| code.put4(tableBase, code.entryPoint(stateSwitch) - startpc); |
| } |
| |
| if (opcode == tableswitch) { |
| // Let any unfilled slots point to the default case. |
| int defaultOffset = code.get4(tableBase); |
| for (long i = lo; i <= hi; i++) { |
| int t = (int)(tableBase + 4 * (i - lo + 3)); |
| if (code.get4(t) == -1) |
| code.put4(t, defaultOffset); |
| } |
| } else { |
| // Sort non-default offsets and copy into lookup table. |
| if (defaultIndex >= 0) |
| for (int i = defaultIndex; i < labels.length - 1; i++) { |
| labels[i] = labels[i+1]; |
| offsets[i] = offsets[i+1]; |
| } |
| if (nlabels > 0) |
| qsort2(labels, offsets, 0, nlabels - 1); |
| for (int i = 0; i < nlabels; i++) { |
| int caseidx = tableBase + 8 * (i + 1); |
| code.put4(caseidx, labels[i]); |
| code.put4(caseidx + 4, offsets[i]); |
| } |
| } |
| } |
| code.endScopes(limit); |
| } |
| //where |
| /** Sort (int) arrays of keys and values |
| */ |
| static void qsort2(int[] keys, int[] values, int lo, int hi) { |
| int i = lo; |
| int j = hi; |
| int pivot = keys[(i+j)/2]; |
| do { |
| while (keys[i] < pivot) i++; |
| while (pivot < keys[j]) j--; |
| if (i <= j) { |
| int temp1 = keys[i]; |
| keys[i] = keys[j]; |
| keys[j] = temp1; |
| int temp2 = values[i]; |
| values[i] = values[j]; |
| values[j] = temp2; |
| i++; |
| j--; |
| } |
| } while (i <= j); |
| if (lo < j) qsort2(keys, values, lo, j); |
| if (i < hi) qsort2(keys, values, i, hi); |
| } |
| |
| public void visitSynchronized(JCSynchronized tree) { |
| int limit = code.nextreg; |
| // Generate code to evaluate lock and save in temporary variable. |
| final LocalItem lockVar = makeTemp(syms.objectType); |
| Assert.check(code.state.stacksize == 0); |
| genExpr(tree.lock, tree.lock.type).load().duplicate(); |
| lockVar.store(); |
| |
| // Generate code to enter monitor. |
| code.emitop0(monitorenter); |
| code.state.lock(lockVar.reg); |
| |
| // Generate code for a try statement with given body, no catch clauses |
| // in a new environment with the "exit-monitor" operation as finalizer. |
| final Env<GenContext> syncEnv = env.dup(tree, new GenContext()); |
| syncEnv.info.finalize = new GenFinalizer() { |
| void gen() { |
| genLast(); |
| Assert.check(syncEnv.info.gaps.length() % 2 == 0); |
| syncEnv.info.gaps.append(code.curCP()); |
| } |
| void genLast() { |
| if (code.isAlive()) { |
| lockVar.load(); |
| code.emitop0(monitorexit); |
| code.state.unlock(lockVar.reg); |
| } |
| } |
| }; |
| syncEnv.info.gaps = new ListBuffer<>(); |
| genTry(tree.body, List.<JCCatch>nil(), syncEnv); |
| code.endScopes(limit); |
| } |
| |
| public void visitTry(final JCTry tree) { |
| // Generate code for a try statement with given body and catch clauses, |
| // in a new environment which calls the finally block if there is one. |
| final Env<GenContext> tryEnv = env.dup(tree, new GenContext()); |
| final Env<GenContext> oldEnv = env; |
| tryEnv.info.finalize = new GenFinalizer() { |
| void gen() { |
| Assert.check(tryEnv.info.gaps.length() % 2 == 0); |
| tryEnv.info.gaps.append(code.curCP()); |
| genLast(); |
| } |
| void genLast() { |
| if (tree.finalizer != null) |
| genStat(tree.finalizer, oldEnv, CRT_BLOCK); |
| } |
| boolean hasFinalizer() { |
| return tree.finalizer != null; |
| } |
| }; |
| tryEnv.info.gaps = new ListBuffer<>(); |
| genTry(tree.body, tree.catchers, tryEnv); |
| } |
| //where |
| /** Generate code for a try or synchronized statement |
| * @param body The body of the try or synchronized statement. |
| * @param catchers The lis of catch clauses. |
| * @param env the environment current for the body. |
| */ |
| void genTry(JCTree body, List<JCCatch> catchers, Env<GenContext> env) { |
| int limit = code.nextreg; |
| int startpc = code.curCP(); |
| Code.State stateTry = code.state.dup(); |
| genStat(body, env, CRT_BLOCK); |
| int endpc = code.curCP(); |
| boolean hasFinalizer = |
| env.info.finalize != null && |
| env.info.finalize.hasFinalizer(); |
| List<Integer> gaps = env.info.gaps.toList(); |
| code.statBegin(TreeInfo.endPos(body)); |
| genFinalizer(env); |
| code.statBegin(TreeInfo.endPos(env.tree)); |
| Chain exitChain = code.branch(goto_); |
| endFinalizerGap(env); |
| if (startpc != endpc) for (List<JCCatch> l = catchers; l.nonEmpty(); l = l.tail) { |
| // start off with exception on stack |
| code.entryPoint(stateTry, l.head.param.sym.type); |
| genCatch(l.head, env, startpc, endpc, gaps); |
| genFinalizer(env); |
| if (hasFinalizer || l.tail.nonEmpty()) { |
| code.statBegin(TreeInfo.endPos(env.tree)); |
| exitChain = Code.mergeChains(exitChain, |
| code.branch(goto_)); |
| } |
| endFinalizerGap(env); |
| } |
| if (hasFinalizer) { |
| // Create a new register segement to avoid allocating |
| // the same variables in finalizers and other statements. |
| code.newRegSegment(); |
| |
| // Add a catch-all clause. |
| |
| // start off with exception on stack |
| int catchallpc = code.entryPoint(stateTry, syms.throwableType); |
| |
| // Register all exception ranges for catch all clause. |
| // The range of the catch all clause is from the beginning |
| // of the try or synchronized block until the present |
| // code pointer excluding all gaps in the current |
| // environment's GenContext. |
| int startseg = startpc; |
| while (env.info.gaps.nonEmpty()) { |
| int endseg = env.info.gaps.next().intValue(); |
| registerCatch(body.pos(), startseg, endseg, |
| catchallpc, 0); |
| startseg = env.info.gaps.next().intValue(); |
| } |
| code.statBegin(TreeInfo.finalizerPos(env.tree)); |
| code.markStatBegin(); |
| |
| Item excVar = makeTemp(syms.throwableType); |
| excVar.store(); |
| genFinalizer(env); |
| excVar.load(); |
| registerCatch(body.pos(), startseg, |
| env.info.gaps.next().intValue(), |
| catchallpc, 0); |
| code.emitop0(athrow); |
| code.markDead(); |
| |
| // If there are jsr's to this finalizer, ... |
| if (env.info.cont != null) { |
| // Resolve all jsr's. |
| code.resolve(env.info.cont); |
| |
| // Mark statement line number |
| code.statBegin(TreeInfo.finalizerPos(env.tree)); |
| code.markStatBegin(); |
| |
| // Save return address. |
| LocalItem retVar = makeTemp(syms.throwableType); |
| retVar.store(); |
| |
| // Generate finalizer code. |
| env.info.finalize.genLast(); |
| |
| // Return. |
| code.emitop1w(ret, retVar.reg); |
| code.markDead(); |
| } |
| } |
| // Resolve all breaks. |
| code.resolve(exitChain); |
| |
| code.endScopes(limit); |
| } |
| |
| /** Generate code for a catch clause. |
| * @param tree The catch clause. |
| * @param env The environment current in the enclosing try. |
| * @param startpc Start pc of try-block. |
| * @param endpc End pc of try-block. |
| */ |
| void genCatch(JCCatch tree, |
| Env<GenContext> env, |
| int startpc, int endpc, |
| List<Integer> gaps) { |
| if (startpc != endpc) { |
| List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypeExprs |
| = catchTypesWithAnnotations(tree); |
| while (gaps.nonEmpty()) { |
| for (Pair<List<Attribute.TypeCompound>, JCExpression> subCatch1 : catchTypeExprs) { |
| JCExpression subCatch = subCatch1.snd; |
| int catchType = makeRef(tree.pos(), subCatch.type); |
| int end = gaps.head.intValue(); |
| registerCatch(tree.pos(), |
| startpc, end, code.curCP(), |
| catchType); |
| for (Attribute.TypeCompound tc : subCatch1.fst) { |
| tc.position.setCatchInfo(catchType, startpc); |
| } |
| } |
| gaps = gaps.tail; |
| startpc = gaps.head.intValue(); |
| gaps = gaps.tail; |
| } |
| if (startpc < endpc) { |
| for (Pair<List<Attribute.TypeCompound>, JCExpression> subCatch1 : catchTypeExprs) { |
| JCExpression subCatch = subCatch1.snd; |
| int catchType = makeRef(tree.pos(), subCatch.type); |
| registerCatch(tree.pos(), |
| startpc, endpc, code.curCP(), |
| catchType); |
| for (Attribute.TypeCompound tc : subCatch1.fst) { |
| tc.position.setCatchInfo(catchType, startpc); |
| } |
| } |
| } |
| VarSymbol exparam = tree.param.sym; |
| code.statBegin(tree.pos); |
| code.markStatBegin(); |
| int limit = code.nextreg; |
| code.newLocal(exparam); |
| items.makeLocalItem(exparam).store(); |
| code.statBegin(TreeInfo.firstStatPos(tree.body)); |
| genStat(tree.body, env, CRT_BLOCK); |
| code.endScopes(limit); |
| code.statBegin(TreeInfo.endPos(tree.body)); |
| } |
| } |
| // where |
| List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypesWithAnnotations(JCCatch tree) { |
| return TreeInfo.isMultiCatch(tree) ? |
| catchTypesWithAnnotationsFromMulticatch((JCTypeUnion)tree.param.vartype, tree.param.sym.getRawTypeAttributes()) : |
| List.of(new Pair<>(tree.param.sym.getRawTypeAttributes(), tree.param.vartype)); |
| } |
| // where |
| List<Pair<List<Attribute.TypeCompound>, JCExpression>> catchTypesWithAnnotationsFromMulticatch(JCTypeUnion tree, List<TypeCompound> first) { |
| List<JCExpression> alts = tree.alternatives; |
| List<Pair<List<TypeCompound>, JCExpression>> res = List.of(new Pair<>(first, alts.head)); |
| alts = alts.tail; |
| |
| while(alts != null && alts.head != null) { |
| JCExpression alt = alts.head; |
| if (alt instanceof JCAnnotatedType) { |
| JCAnnotatedType a = (JCAnnotatedType)alt; |
| res = res.prepend(new Pair<>(annotate.fromAnnotations(a.annotations), alt)); |
| } else { |
| res = res.prepend(new Pair<>(List.nil(), alt)); |
| } |
| alts = alts.tail; |
| } |
| return res.reverse(); |
| } |
| |
| /** Register a catch clause in the "Exceptions" code-attribute. |
| */ |
| void registerCatch(DiagnosticPosition pos, |
| int startpc, int endpc, |
| int handler_pc, int catch_type) { |
| char startpc1 = (char)startpc; |
| char endpc1 = (char)endpc; |
| char handler_pc1 = (char)handler_pc; |
| if (startpc1 == startpc && |
| endpc1 == endpc && |
| handler_pc1 == handler_pc) { |
| code.addCatch(startpc1, endpc1, handler_pc1, |
| (char)catch_type); |
| } else { |
| log.error(pos, "limit.code.too.large.for.try.stmt"); |
| nerrs++; |
| } |
| } |
| |
| public void visitIf(JCIf tree) { |
| int limit = code.nextreg; |
| Chain thenExit = null; |
| Assert.check(code.state.stacksize == 0); |
| CondItem c = genCond(TreeInfo.skipParens(tree.cond), |
| CRT_FLOW_CONTROLLER); |
| Chain elseChain = c.jumpFalse(); |
| Assert.check(code.state.stacksize == 0); |
| if (!c.isFalse()) { |
| code.resolve(c.trueJumps); |
| genStat(tree.thenpart, env, CRT_STATEMENT | CRT_FLOW_TARGET); |
| thenExit = code.branch(goto_); |
| } |
| if (elseChain != null) { |
| code.resolve(elseChain); |
| if (tree.elsepart != null) { |
| genStat(tree.elsepart, env,CRT_STATEMENT | CRT_FLOW_TARGET); |
| } |
| } |
| code.resolve(thenExit); |
| code.endScopes(limit); |
| Assert.check(code.state.stacksize == 0); |
| } |
| |
| public void visitExec(JCExpressionStatement tree) { |
| // Optimize x++ to ++x and x-- to --x. |
| JCExpression e = tree.expr; |
| switch (e.getTag()) { |
| case POSTINC: |
| ((JCUnary) e).setTag(PREINC); |
| break; |
| case POSTDEC: |
| ((JCUnary) e).setTag(PREDEC); |
| break; |
| } |
| Assert.check(code.state.stacksize == 0); |
| genExpr(tree.expr, tree.expr.type).drop(); |
| Assert.check(code.state.stacksize == 0); |
| } |
| |
| public void visitBreak(JCBreak tree) { |
| Env<GenContext> targetEnv = unwind(tree.target, env); |
| Assert.check(code.state.stacksize == 0); |
| targetEnv.info.addExit(code.branch(goto_)); |
| endFinalizerGaps(env, targetEnv); |
| } |
| |
| public void visitContinue(JCContinue tree) { |
| Env<GenContext> targetEnv = unwind(tree.target, env); |
| Assert.check(code.state.stacksize == 0); |
| targetEnv.info.addCont(code.branch(goto_)); |
| endFinalizerGaps(env, targetEnv); |
| } |
| |
| public void visitReturn(JCReturn tree) { |
| int limit = code.nextreg; |
| final Env<GenContext> targetEnv; |
| |
| /* Save and then restore the location of the return in case a finally |
| * is expanded (with unwind()) in the middle of our bytecodes. |
| */ |
| int tmpPos = code.pendingStatPos; |
| if (tree.expr != null) { |
| Assert.check(code.state.stacksize == 0); |
| Item r = genExpr(tree.expr, pt).load(); |
| if (hasFinally(env.enclMethod, env)) { |
| r = makeTemp(pt); |
| r.store(); |
| } |
| targetEnv = unwind(env.enclMethod, env); |
| code.pendingStatPos = tmpPos; |
| r.load(); |
| code.emitop0(ireturn + Code.truncate(Code.typecode(pt))); |
| } else { |
| targetEnv = unwind(env.enclMethod, env); |
| code.pendingStatPos = tmpPos; |
| code.emitop0(return_); |
| } |
| endFinalizerGaps(env, targetEnv); |
| code.endScopes(limit); |
| } |
| |
| public void visitThrow(JCThrow tree) { |
| Assert.check(code.state.stacksize == 0); |
| genExpr(tree.expr, tree.expr.type).load(); |
| code.emitop0(athrow); |
| Assert.check(code.state.stacksize == 0); |
| } |
| |
| /* ************************************************************************ |
| * Visitor methods for expressions |
| *************************************************************************/ |
| |
| public void visitApply(JCMethodInvocation tree) { |
| setTypeAnnotationPositions(tree.pos); |
| // Generate code for method. |
| Item m = genExpr(tree.meth, methodType); |
| // Generate code for all arguments, where the expected types are |
| // the parameters of the method's external type (that is, any implicit |
| // outer instance of a super(...) call appears as first parameter). |
| MethodSymbol msym = (MethodSymbol)TreeInfo.symbol(tree.meth); |
| genArgs(tree.args, |
| msym.externalType(types).getParameterTypes()); |
| if (!msym.isDynamic()) { |
| code.statBegin(tree.pos); |
| } |
| result = m.invoke(); |
| } |
| |
| public void visitConditional(JCConditional tree) { |
| Chain thenExit = null; |
| CondItem c = genCond(tree.cond, CRT_FLOW_CONTROLLER); |
| Chain elseChain = c.jumpFalse(); |
| if (!c.isFalse()) { |
| code.resolve(c.trueJumps); |
| int startpc = genCrt ? code.curCP() : 0; |
| code.statBegin(tree.truepart.pos); |
| genExpr(tree.truepart, pt).load(); |
| code.state.forceStackTop(tree.type); |
| if (genCrt) code.crt.put(tree.truepart, CRT_FLOW_TARGET, |
| startpc, code.curCP()); |
| thenExit = code.branch(goto_); |
| } |
| if (elseChain != null) { |
| code.resolve(elseChain); |
| int startpc = genCrt ? code.curCP() : 0; |
| code.statBegin(tree.falsepart.pos); |
| genExpr(tree.falsepart, pt).load(); |
| code.state.forceStackTop(tree.type); |
| if (genCrt) code.crt.put(tree.falsepart, CRT_FLOW_TARGET, |
| startpc, code.curCP()); |
| } |
| code.resolve(thenExit); |
| result = items.makeStackItem(pt); |
| } |
| |
| private void setTypeAnnotationPositions(int treePos) { |
| MethodSymbol meth = code.meth; |
| boolean initOrClinit = code.meth.getKind() == javax.lang.model.element.ElementKind.CONSTRUCTOR |
| || code.meth.getKind() == javax.lang.model.element.ElementKind.STATIC_INIT; |
| |
| for (Attribute.TypeCompound ta : meth.getRawTypeAttributes()) { |
| if (ta.hasUnknownPosition()) |
| ta.tryFixPosition(); |
| |
| if (ta.position.matchesPos(treePos)) |
| ta.position.updatePosOffset(code.cp); |
| } |
| |
| if (!initOrClinit) |
| return; |
| |
| for (Attribute.TypeCompound ta : meth.owner.getRawTypeAttributes()) { |
| if (ta.hasUnknownPosition()) |
| ta.tryFixPosition(); |
| |
| if (ta.position.matchesPos(treePos)) |
| ta.position.updatePosOffset(code.cp); |
| } |
| |
| ClassSymbol clazz = meth.enclClass(); |
| for (Symbol s : new com.sun.tools.javac.model.FilteredMemberList(clazz.members())) { |
| if (!s.getKind().isField()) |
| continue; |
| |
| for (Attribute.TypeCompound ta : s.getRawTypeAttributes()) { |
| if (ta.hasUnknownPosition()) |
| ta.tryFixPosition(); |
| |
| if (ta.position.matchesPos(treePos)) |
| ta.position.updatePosOffset(code.cp); |
| } |
| } |
| } |
| |
| public void visitNewClass(JCNewClass tree) { |
| // Enclosing instances or anonymous classes should have been eliminated |
| // by now. |
| Assert.check(tree.encl == null && tree.def == null); |
| setTypeAnnotationPositions(tree.pos); |
| |
| code.emitop2(new_, makeRef(tree.pos(), tree.type)); |
| code.emitop0(dup); |
| |
| // Generate code for all arguments, where the expected types are |
| // the parameters of the constructor's external type (that is, |
| // any implicit outer instance appears as first parameter). |
| genArgs(tree.args, tree.constructor.externalType(types).getParameterTypes()); |
| |
| items.makeMemberItem(tree.constructor, true).invoke(); |
| result = items.makeStackItem(tree.type); |
| } |
| |
| public void visitNewArray(JCNewArray tree) { |
| setTypeAnnotationPositions(tree.pos); |
| |
| if (tree.elems != null) { |
| Type elemtype = types.elemtype(tree.type); |
| loadIntConst(tree.elems.length()); |
| Item arr = makeNewArray(tree.pos(), tree.type, 1); |
| int i = 0; |
| for (List<JCExpression> l = tree.elems; l.nonEmpty(); l = l.tail) { |
| arr.duplicate(); |
| loadIntConst(i); |
| i++; |
| genExpr(l.head, elemtype).load(); |
| items.makeIndexedItem(elemtype).store(); |
| } |
| result = arr; |
| } else { |
| for (List<JCExpression> l = tree.dims; l.nonEmpty(); l = l.tail) { |
| genExpr(l.head, syms.intType).load(); |
| } |
| result = makeNewArray(tree.pos(), tree.type, tree.dims.length()); |
| } |
| } |
| //where |
| /** Generate code to create an array with given element type and number |
| * of dimensions. |
| */ |
| Item makeNewArray(DiagnosticPosition pos, Type type, int ndims) { |
| Type elemtype = types.elemtype(type); |
| if (types.dimensions(type) > ClassFile.MAX_DIMENSIONS) { |
| log.error(pos, "limit.dimensions"); |
| nerrs++; |
| } |
| int elemcode = Code.arraycode(elemtype); |
| if (elemcode == 0 || (elemcode == 1 && ndims == 1)) { |
| code.emitAnewarray(makeRef(pos, elemtype), type); |
| } else if (elemcode == 1) { |
| code.emitMultianewarray(ndims, makeRef(pos, type), type); |
| } else { |
| code.emitNewarray(elemcode, type); |
| } |
| return items.makeStackItem(type); |
| } |
| |
| public void visitParens(JCParens tree) { |
| result = genExpr(tree.expr, tree.expr.type); |
| } |
| |
| public void visitAssign(JCAssign tree) { |
| Item l = genExpr(tree.lhs, tree.lhs.type); |
| genExpr(tree.rhs, tree.lhs.type).load(); |
| if (tree.rhs.type.hasTag(BOT)) { |
| /* This is just a case of widening reference conversion that per 5.1.5 simply calls |
| for "regarding a reference as having some other type in a manner that can be proved |
| correct at compile time." |
| */ |
| code.state.forceStackTop(tree.lhs.type); |
| } |
| result = items.makeAssignItem(l); |
| } |
| |
| public void visitAssignop(JCAssignOp tree) { |
| OperatorSymbol operator = (OperatorSymbol) tree.operator; |
| Item l; |
| if (operator.opcode == string_add) { |
| l = concat.makeConcat(tree); |
| } else { |
| // Generate code for first expression |
| l = genExpr(tree.lhs, tree.lhs.type); |
| |
| // If we have an increment of -32768 to +32767 of a local |
| // int variable we can use an incr instruction instead of |
| // proceeding further. |
| if ((tree.hasTag(PLUS_ASG) || tree.hasTag(MINUS_ASG)) && |
| l instanceof LocalItem && |
| tree.lhs.type.getTag().isSubRangeOf(INT) && |
| tree.rhs.type.getTag().isSubRangeOf(INT) && |
| tree.rhs.type.constValue() != null) { |
| int ival = ((Number) tree.rhs.type.constValue()).intValue(); |
| if (tree.hasTag(MINUS_ASG)) ival = -ival; |
| ((LocalItem)l).incr(ival); |
| result = l; |
| return; |
| } |
| // Otherwise, duplicate expression, load one copy |
| // and complete binary operation. |
| l.duplicate(); |
| l.coerce(operator.type.getParameterTypes().head).load(); |
| completeBinop(tree.lhs, tree.rhs, operator).coerce(tree.lhs.type); |
| } |
| result = items.makeAssignItem(l); |
| } |
| |
| public void visitUnary(JCUnary tree) { |
| OperatorSymbol operator = (OperatorSymbol)tree.operator; |
| if (tree.hasTag(NOT)) { |
| CondItem od = genCond(tree.arg, false); |
| result = od.negate(); |
| } else { |
| Item od = genExpr(tree.arg, operator.type.getParameterTypes().head); |
| switch (tree.getTag()) { |
| case POS: |
| result = od.load(); |
| break; |
| case NEG: |
| result = od.load(); |
| code.emitop0(operator.opcode); |
| break; |
| case COMPL: |
| result = od.load(); |
| emitMinusOne(od.typecode); |
| code.emitop0(operator.opcode); |
| break; |
| case PREINC: case PREDEC: |
| od.duplicate(); |
| if (od instanceof LocalItem && |
| (operator.opcode == iadd || operator.opcode == isub)) { |
| ((LocalItem)od).incr(tree.hasTag(PREINC) ? 1 : -1); |
| result = od; |
| } else { |
| od.load(); |
| code.emitop0(one(od.typecode)); |
| code.emitop0(operator.opcode); |
| // Perform narrowing primitive conversion if byte, |
| // char, or short. Fix for 4304655. |
| if (od.typecode != INTcode && |
| Code.truncate(od.typecode) == INTcode) |
| code.emitop0(int2byte + od.typecode - BYTEcode); |
| result = items.makeAssignItem(od); |
| } |
| break; |
| case POSTINC: case POSTDEC: |
| od.duplicate(); |
| if (od instanceof LocalItem && |
| (operator.opcode == iadd || operator.opcode == isub)) { |
| Item res = od.load(); |
| ((LocalItem)od).incr(tree.hasTag(POSTINC) ? 1 : -1); |
| result = res; |
| } else { |
| Item res = od.load(); |
| od.stash(od.typecode); |
| code.emitop0(one(od.typecode)); |
| code.emitop0(operator.opcode); |
| // Perform narrowing primitive conversion if byte, |
| // char, or short. Fix for 4304655. |
| if (od.typecode != INTcode && |
| Code.truncate(od.typecode) == INTcode) |
| code.emitop0(int2byte + od.typecode - BYTEcode); |
| od.store(); |
| result = res; |
| } |
| break; |
| case NULLCHK: |
| result = od.load(); |
| code.emitop0(dup); |
| genNullCheck(tree.pos()); |
| break; |
| default: |
| Assert.error(); |
| } |
| } |
| } |
| |
| /** Generate a null check from the object value at stack top. */ |
| private void genNullCheck(DiagnosticPosition pos) { |
| if (allowBetterNullChecks) { |
| callMethod(pos, syms.objectsType, names.requireNonNull, |
| List.of(syms.objectType), true); |
| } else { |
| callMethod(pos, syms.objectType, names.getClass, |
| List.<Type>nil(), false); |
| } |
| code.emitop0(pop); |
| } |
| |
| public void visitBinary(JCBinary tree) { |
| OperatorSymbol operator = (OperatorSymbol)tree.operator; |
| if (operator.opcode == string_add) { |
| result = concat.makeConcat(tree); |
| } else if (tree.hasTag(AND)) { |
| CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER); |
| if (!lcond.isFalse()) { |
| Chain falseJumps = lcond.jumpFalse(); |
| code.resolve(lcond.trueJumps); |
| CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET); |
| result = items. |
| makeCondItem(rcond.opcode, |
| rcond.trueJumps, |
| Code.mergeChains(falseJumps, |
| rcond.falseJumps)); |
| } else { |
| result = lcond; |
| } |
| } else if (tree.hasTag(OR)) { |
| CondItem lcond = genCond(tree.lhs, CRT_FLOW_CONTROLLER); |
| if (!lcond.isTrue()) { |
| Chain trueJumps = lcond.jumpTrue(); |
| code.resolve(lcond.falseJumps); |
| CondItem rcond = genCond(tree.rhs, CRT_FLOW_TARGET); |
| result = items. |
| makeCondItem(rcond.opcode, |
| Code.mergeChains(trueJumps, rcond.trueJumps), |
| rcond.falseJumps); |
| } else { |
| result = lcond; |
| } |
| } else { |
| Item od = genExpr(tree.lhs, operator.type.getParameterTypes().head); |
| od.load(); |
| result = completeBinop(tree.lhs, tree.rhs, operator); |
| } |
| } |
| |
| |
| /** Complete generating code for operation, with left operand |
| * already on stack. |
| * @param lhs The tree representing the left operand. |
| * @param rhs The tree representing the right operand. |
| * @param operator The operator symbol. |
| */ |
| Item completeBinop(JCTree lhs, JCTree rhs, OperatorSymbol operator) { |
| MethodType optype = (MethodType)operator.type; |
| int opcode = operator.opcode; |
| if (opcode >= if_icmpeq && opcode <= if_icmple && |
| rhs.type.constValue() instanceof Number && |
| ((Number) rhs.type.constValue()).intValue() == 0) { |
| opcode = opcode + (ifeq - if_icmpeq); |
| } else if (opcode >= if_acmpeq && opcode <= if_acmpne && |
| TreeInfo.isNull(rhs)) { |
| opcode = opcode + (if_acmp_null - if_acmpeq); |
| } else { |
| // The expected type of the right operand is |
| // the second parameter type of the operator, except for |
| // shifts with long shiftcount, where we convert the opcode |
| // to a short shift and the expected type to int. |
| Type rtype = operator.erasure(types).getParameterTypes().tail.head; |
| if (opcode >= ishll && opcode <= lushrl) { |
| opcode = opcode + (ishl - ishll); |
| rtype = syms.intType; |
| } |
| // Generate code for right operand and load. |
| genExpr(rhs, rtype).load(); |
| // If there are two consecutive opcode instructions, |
| // emit the first now. |
| if (opcode >= (1 << preShift)) { |
| code.emitop0(opcode >> preShift); |
| opcode = opcode & 0xFF; |
| } |
| } |
| if (opcode >= ifeq && opcode <= if_acmpne || |
| opcode == if_acmp_null || opcode == if_acmp_nonnull) { |
| return items.makeCondItem(opcode); |
| } else { |
| code.emitop0(opcode); |
| return items.makeStackItem(optype.restype); |
| } |
| } |
| |
| public void visitTypeCast(JCTypeCast tree) { |
| result = genExpr(tree.expr, tree.clazz.type).load(); |
| setTypeAnnotationPositions(tree.pos); |
| // Additional code is only needed if we cast to a reference type |
| // which is not statically a supertype of the expression's type. |
| // For basic types, the coerce(...) in genExpr(...) will do |
| // the conversion. |
| if (!tree.clazz.type.isPrimitive() && |
| !types.isSameType(tree.expr.type, tree.clazz.type) && |
| types.asSuper(tree.expr.type, tree.clazz.type.tsym) == null) { |
| code.emitop2(checkcast, makeRef(tree.pos(), tree.clazz.type)); |
| } |
| } |
| |
| public void visitWildcard(JCWildcard tree) { |
| throw new AssertionError(this.getClass().getName()); |
| } |
| |
| public void visitTypeTest(JCInstanceOf tree) { |
| genExpr(tree.expr, tree.expr.type).load(); |
| setTypeAnnotationPositions(tree.pos); |
| code.emitop2(instanceof_, makeRef(tree.pos(), tree.clazz.type)); |
| result = items.makeStackItem(syms.booleanType); |
| } |
| |
| public void visitIndexed(JCArrayAccess tree) { |
| genExpr(tree.indexed, tree.indexed.type).load(); |
| genExpr(tree.index, syms.intType).load(); |
| result = items.makeIndexedItem(tree.type); |
| } |
| |
| public void visitIdent(JCIdent tree) { |
| Symbol sym = tree.sym; |
| if (tree.name == names._this || tree.name == names._super) { |
| Item res = tree.name == names._this |
| ? items.makeThisItem() |
| : items.makeSuperItem(); |
| if (sym.kind == MTH) { |
| // Generate code to address the constructor. |
| res.load(); |
| res = items.makeMemberItem(sym, true); |
| } |
| result = res; |
| } else if (sym.kind == VAR && sym.owner.kind == MTH) { |
| result = items.makeLocalItem((VarSymbol)sym); |
| } else if (isInvokeDynamic(sym)) { |
| result = items.makeDynamicItem(sym); |
| } else if ((sym.flags() & STATIC) != 0) { |
| if (!isAccessSuper(env.enclMethod)) |
| sym = binaryQualifier(sym, env.enclClass.type); |
| result = items.makeStaticItem(sym); |
| } else { |
| items.makeThisItem().load(); |
| sym = binaryQualifier(sym, env.enclClass.type); |
| result = items.makeMemberItem(sym, (sym.flags() & PRIVATE) != 0); |
| } |
| } |
| |
| public void visitSelect(JCFieldAccess tree) { |
| Symbol sym = tree.sym; |
| |
| if (tree.name == names._class) { |
| code.emitLdc(makeRef(tree.pos(), tree.selected.type)); |
| result = items.makeStackItem(pt); |
| return; |
| } |
| |
| Symbol ssym = TreeInfo.symbol(tree.selected); |
| |
| // Are we selecting via super? |
| boolean selectSuper = |
| ssym != null && (ssym.kind == TYP || ssym.name == names._super); |
| |
| // Are we accessing a member of the superclass in an access method |
| // resulting from a qualified super? |
| boolean accessSuper = isAccessSuper(env.enclMethod); |
| |
| Item base = (selectSuper) |
| ? items.makeSuperItem() |
| : genExpr(tree.selected, tree.selected.type); |
| |
| if (sym.kind == VAR && ((VarSymbol) sym).getConstValue() != null) { |
| // We are seeing a variable that is constant but its selecting |
| // expression is not. |
| if ((sym.flags() & STATIC) != 0) { |
| if (!selectSuper && (ssym == null || ssym.kind != TYP)) |
| base = base.load(); |
| base.drop(); |
| } else { |
| base.load(); |
| genNullCheck(tree.selected.pos()); |
| } |
| result = items. |
| makeImmediateItem(sym.type, ((VarSymbol) sym).getConstValue()); |
| } else { |
| if (isInvokeDynamic(sym)) { |
| result = items.makeDynamicItem(sym); |
| return; |
| } else { |
| sym = binaryQualifier(sym, tree.selected.type); |
| } |
| if ((sym.flags() & STATIC) != 0) { |
| if (!selectSuper && (ssym == null || ssym.kind != TYP)) |
| base = base.load(); |
| base.drop(); |
| result = items.makeStaticItem(sym); |
| } else { |
| base.load(); |
| if (sym == syms.lengthVar) { |
| code.emitop0(arraylength); |
| result = items.makeStackItem(syms.intType); |
| } else { |
| result = items. |
| makeMemberItem(sym, |
| (sym.flags() & PRIVATE) != 0 || |
| selectSuper || accessSuper); |
| } |
| } |
| } |
| } |
| |
| public boolean isInvokeDynamic(Symbol sym) { |
| return sym.kind == MTH && ((MethodSymbol)sym).isDynamic(); |
| } |
| |
| public void visitLiteral(JCLiteral tree) { |
| if (tree.type.hasTag(BOT)) { |
| code.emitop0(aconst_null); |
| result = items.makeStackItem(tree.type); |
| } |
| else |
| result = items.makeImmediateItem(tree.type, tree.value); |
| } |
| |
| public void visitLetExpr(LetExpr tree) { |
| letExprDepth++; |
| int limit = code.nextreg; |
| genStats(tree.defs, env); |
| result = genExpr(tree.expr, tree.expr.type).load(); |
| code.endScopes(limit); |
| letExprDepth--; |
| } |
| |
| private void generateReferencesToPrunedTree(ClassSymbol classSymbol, Pool pool) { |
| List<JCTree> prunedInfo = lower.prunedTree.get(classSymbol); |
| if (prunedInfo != null) { |
| for (JCTree prunedTree: prunedInfo) { |
| prunedTree.accept(classReferenceVisitor); |
| } |
| } |
| } |
| |
| /* ************************************************************************ |
| * main method |
| *************************************************************************/ |
| |
| /** Generate code for a class definition. |
| * @param env The attribution environment that belongs to the |
| * outermost class containing this class definition. |
| * We need this for resolving some additional symbols. |
| * @param cdef The tree representing the class definition. |
| * @return True if code is generated with no errors. |
| */ |
| public boolean genClass(Env<AttrContext> env, JCClassDecl cdef) { |
| try { |
| attrEnv = env; |
| ClassSymbol c = cdef.sym; |
| this.toplevel = env.toplevel; |
| this.endPosTable = toplevel.endPositions; |
| c.pool = pool; |
| pool.reset(); |
| /* method normalizeDefs() can add references to external classes into the constant pool |
| */ |
| cdef.defs = normalizeDefs(cdef.defs, c); |
| generateReferencesToPrunedTree(c, pool); |
| Env<GenContext> localEnv = new Env<>(cdef, new GenContext()); |
| localEnv.toplevel = env.toplevel; |
| localEnv.enclClass = cdef; |
| |
| for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) { |
| genDef(l.head, localEnv); |
| } |
| if (pool.numEntries() > Pool.MAX_ENTRIES) { |
| log.error(cdef.pos(), "limit.pool"); |
| nerrs++; |
| } |
| if (nerrs != 0) { |
| // if errors, discard code |
| for (List<JCTree> l = cdef.defs; l.nonEmpty(); l = l.tail) { |
| if (l.head.hasTag(METHODDEF)) |
| ((JCMethodDecl) l.head).sym.code = null; |
| } |
| } |
| cdef.defs = List.nil(); // discard trees |
| return nerrs == 0; |
| } finally { |
| // note: this method does NOT support recursion. |
| attrEnv = null; |
| this.env = null; |
| toplevel = null; |
| endPosTable = null; |
| nerrs = 0; |
| } |
| } |
| |
| /* ************************************************************************ |
| * Auxiliary classes |
| *************************************************************************/ |
| |
| /** An abstract class for finalizer generation. |
| */ |
| abstract class GenFinalizer { |
| /** Generate code to clean up when unwinding. */ |
| abstract void gen(); |
| |
| /** Generate code to clean up at last. */ |
| abstract void genLast(); |
| |
| /** Does this finalizer have some nontrivial cleanup to perform? */ |
| boolean hasFinalizer() { return true; } |
| } |
| |
| /** code generation contexts, |
| * to be used as type parameter for environments. |
| */ |
| static class GenContext { |
| |
| /** A chain for all unresolved jumps that exit the current environment. |
| */ |
| Chain exit = null; |
| |
| /** A chain for all unresolved jumps that continue in the |
| * current environment. |
| */ |
| Chain cont = null; |
| |
| /** A closure that generates the finalizer of the current environment. |
| * Only set for Synchronized and Try contexts. |
| */ |
| GenFinalizer finalize = null; |
| |
| /** Is this a switch statement? If so, allocate registers |
| * even when the variable declaration is unreachable. |
| */ |
| boolean isSwitch = false; |
| |
| /** A list buffer containing all gaps in the finalizer range, |
| * where a catch all exception should not apply. |
| */ |
| ListBuffer<Integer> gaps = null; |
| |
| /** Add given chain to exit chain. |
| */ |
| void addExit(Chain c) { |
| exit = Code.mergeChains(c, exit); |
| } |
| |
| /** Add given chain to cont chain. |
| */ |
| void addCont(Chain c) { |
| cont = Code.mergeChains(c, cont); |
| } |
| } |
| |
| } |