Equivalent .class fields should share the same symbol

[B. Blaser]

Is there something left to do with this?
Tier1 seems OK (jdk & langtools are successful and hotspot looks quite
good modulo some unrelated issues on my system [1]).

Thanks,
Bernard

[1] http://mail.openjdk.java.net/pipermail/amber-dev/2018-April/003031.html

On 17 April 2018 at 00:28, B. Blaser <bsrbnd at gmail.com> wrote:
> On 16 April 2018 at 19:40, Jan Lahoda <jan.lahoda at oracle.com> wrote:
>> On 16.4.2018 19:31, B. Blaser wrote:
>>>
>>> Hi Jan,
>>>
>>> On 16 April 2018 at 17:02, Jan Lahoda <jan.lahoda at oracle.com> wrote:
>>>>
>>>> Hi Bernard,
>>>>
>>>> [...]
>>>>
>>>> -should there be a method in Symtab managing the map? Something like:
>>>> Symtab.getClassField(TypeSymbol tsym) {/*create the VarSymbol is
>>>> needed*/}
>>>
>>>
>>> I'll take a look if you think it's worth adding a method for this.
>>
>>
>> I think it would be nicer than maintaining the map from another class, if
>> possible/doable.
>>
>> Thanks,
>>     Jan
>
> Here it is, javac tests are OK.
> Cheers,
> Bernard
>
> diff -r 8c85a1855e10
> src/jdk.compiler/share/classes/com/sun/tools/javac/code/Symtab.java
> --- a/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Symtab.java
> Fri Apr 13 11:14:49 2018 -0700
> +++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/code/Symtab.java
> Mon Apr 16 23:33:02 2018 +0200
> @@ -1,5 +1,5 @@
>  /*
> - * Copyright (c) 1999, 2017, Oracle and/or its affiliates. All rights reserved.
> + * Copyright (c) 1999, 2018, 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
> @@ -51,6 +51,7 @@
>  import com.sun.tools.javac.code.Type.JCVoidType;
>  import com.sun.tools.javac.code.Type.MethodType;
>  import com.sun.tools.javac.code.Type.UnknownType;
> +import com.sun.tools.javac.code.Types.UniqueType;
>  import com.sun.tools.javac.comp.Modules;
>  import com.sun.tools.javac.util.Assert;
>  import com.sun.tools.javac.util.Context;
> @@ -247,6 +248,26 @@
>       */
>      private final Map<Name, ModuleSymbol> modules = new LinkedHashMap<>();
>
> +    private final Map<Types.UniqueType, VarSymbol> classFields = new
> HashMap<>();
> +
> +    public VarSymbol getClassField(Type type, Types types) {
> +        return classFields.computeIfAbsent(
> +            new UniqueType(type, types), k -> {
> +                Type arg = null;
> +                if (type.getTag() == ARRAY || type.getTag() == CLASS)
> +                    arg = types.erasure(type);
> +                else if (type.isPrimitiveOrVoid())
> +                    arg = types.boxedClass(type).type;
> +                else
> +                    throw new AssertionError(type);
> +
> +                Type t = new ClassType(
> +                    classType.getEnclosingType(), List.of(arg),
> classType.tsym);
> +                return new VarSymbol(
> +                    STATIC | PUBLIC | FINAL, names._class, t, type.tsym);
> +            });
> +    }
> +
>      public void initType(Type type, ClassSymbol c) {
>          type.tsym = c;
>          typeOfTag[type.getTag().ordinal()] = type;
> diff -r 8c85a1855e10
> src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java
> --- a/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java
> Fri Apr 13 11:14:49 2018 -0700
> +++ b/src/jdk.compiler/share/classes/com/sun/tools/javac/comp/Attr.java
> Mon Apr 16 23:33:02 2018 +0200
> @@ -3731,11 +3731,7 @@
>                  } else if (name == names._class) {
>                      // In this case, we have already made sure in
>                      // visitSelect that qualifier expression is a type.
> -                    Type t = syms.classType;
> -                    List<Type> typeargs = List.of(types.erasure(site));
> -                    t = new ClassType(t.getEnclosingType(), typeargs, t.tsym);
> -                    return new VarSymbol(
> -                        STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
> +                    return syms.getClassField(site, types);
>                  } else {
>                      // We are seeing a plain identifier as selector.
>                      Symbol sym = rs.findIdentInType(env, site, name,
> resultInfo.pkind);
> @@ -3773,11 +3769,7 @@
>                  if (name == names._class) {
>                      // In this case, we have already made sure in Select that
>                      // qualifier expression is a type.
> -                    Type t = syms.classType;
> -                    Type arg = types.boxedClass(site).type;
> -                    t = new ClassType(t.getEnclosingType(),
> List.of(arg), t.tsym);
> -                    return new VarSymbol(
> -                        STATIC | PUBLIC | FINAL, names._class, t, site.tsym);
> +                    return syms.getClassField(site, types);
>                  } else {
>                      log.error(pos, Errors.CantDeref(site));
>                      return syms.errSymbol;
> diff -r 8c85a1855e10
> test/langtools/tools/javac/lambda/deduplication/Deduplication.java
> --- a/test/langtools/tools/javac/lambda/deduplication/Deduplication.java
> Fri Apr 13 11:14:49 2018 -0700
> +++ b/test/langtools/tools/javac/lambda/deduplication/Deduplication.java
> Mon Apr 16 23:33:02 2018 +0200
> @@ -38,6 +38,31 @@
>                  (Runnable) () -> { ( (Runnable) () -> {} ).run(); }
>          );
>
> +        group(
> +                (Runnable) () -> { Deduplication.class.toString(); },
> +                (Runnable) () -> { Deduplication.class.toString(); }
> +        );
> +
> +        group(
> +                (Runnable) () -> { Integer[].class.toString(); },
> +                (Runnable) () -> { Integer[].class.toString(); }
> +        );
> +
> +        group(
> +                (Runnable) () -> { char.class.toString(); },
> +                (Runnable) () -> { char.class.toString(); }
> +        );
> +
> +        group(
> +                (Runnable) () -> { Void.class.toString(); },
> +                (Runnable) () -> { Void.class.toString(); }
> +        );
> +
> +        group(
> +                (Runnable) () -> { void.class.toString(); },
> +                (Runnable) () -> { void.class.toString(); }
> +        );
> +
>          group((Function<String, Integer>) x -> x.hashCode());
>          group((Function<Object, Integer>) x -> x.hashCode());