SquirrelJME/SquirrelJME

# 2015/11/03

***DISCLAIMER***: _These notes are from the defunct k8 project which_
_precedes SquirrelJME. The notes for SquirrelJME start on 2016/02/26!_
_The k8 project was effectively a Java SE 8 operating system and as such_
_all of the notes are in the context of that scope. That project is no_
_longer my goal as SquirrelJME is the spiritual successor to it._

## 10:34

Awake now.

## 13:10

I believe I am going to remove the boolean return type for the generation
arguments.

## 13:49

Also splitting the translator away from POITDynaRec into a new class makes it
much better also.

## 14:01

I dislike it when the last commit I want to make does not get committed so it
is delayed until I commit next. However, the refactoring of the base class is
much nicer now and there were massive import cleanups too. POITDynaRec is also
much simpler and easier to read with all of the translation stuff in another
class.

## 18:01

Found a bug in StandardBindings, was using int registers instead of float ones.
And I only found that out after a refactor because the new code is much more
strict.

## 21:05

Need stack map table handling for `synchronized (this)`.

## 21:59

RISC-V looks interesting. I do wonder though how I will handle synchronization
since I have never done that before. I can just setup a bunch of code that is
rather simple and then just look at the javap result of it.

Can see that the inner static does monitorenter on class Bar.

    public static void staticInner();
    descriptor: ()V
    flags: ACC_PUBLIC, ACC_STATIC
    Code:
    stack=3, locals=2, args_size=0
    0: ldc           #2      // class Bar
    2: dup
    3: astore_0
    4: monitorenter
    5: getstatic     #3      // Field java/lang/System.out:Ljava/io/PrintS
    8: ldc           #4      // String Static inner.
    10: invokevirtual #5      // Method java/io/PrintStream.println:(Ljava
    13: new           #6      // class java/lang/UnknownError
    16: dup
    17: ldc           #7      // String TODO
    19: invokespecial #8      // Method java/lang/UnknownError."<init>":(L
    22: athrow
    23: astore_1
    24: aload_0
    25: monitorexit
    26: aload_1
    27: athrow
    Exception table:
    from    to  target type
    5    26    23   any
    LineNumberTable:
    line 5: 0
    line 7: 5
    line 8: 13
    line 9: 23
    StackMapTable: number_of_entries = 1
    frame_type = 255 /* full_frame */
    offset_delta = 23
    locals = [ class java/lang/Object ]
    stack = [ class java/lang/Throwable ]

While the outer code has no monitor code at all.

    public static synchronized void staticOuter();
    descriptor: ()V
    flags: ACC_PUBLIC, ACC_STATIC, ACC_SYNCHRONIZED
    Code:
    stack=3, locals=0, args_size=0
    0: getstatic     #3      // Field java/lang/System.out:Ljava/io/PrintS
    3: ldc           #9      // String Static outer.
    5: invokevirtual #5      // Method java/io/PrintStream.println:(Ljava/
    8: new           #6      // class java/lang/UnknownError
    11: dup
    12: ldc           #7      // String TODO
    14: invokespecial #8      // Method java/lang/UnknownError."<init>":(L
    17: athrow
    LineNumberTable:
    line 14: 0
    line 15: 8

The outer lacks a stack map table also.

    public void instanceInner();
    descriptor: ()V
    flags: ACC_PUBLIC
    Code:
    stack=3, locals=3, args_size=1
    0: aload_0
    1: dup
    2: astore_1
    3: monitorenter
    4: getstatic     #3      // Field java/lang/System.out:Ljava/io/PrintS
    7: ldc           #10     // String Instance inner.
    9: invokevirtual #5      // Method java/io/PrintStream.println:(Ljava/
    12: new           #6      // class java/lang/UnknownError
    15: dup
    16: ldc           #7      // String TODO
    18: invokespecial #8      // Method java/lang/UnknownError."<init>":(L
    21: athrow
    22: astore_2
    23: aload_1
    24: monitorexit
    25: aload_2
    26: athrow
    Exception table:
    from    to  target type
    4    25    22   any
    LineNumberTable:
    line 20: 0
    line 22: 4
    line 23: 12
    line 24: 22
    StackMapTable: number_of_entries = 1
    frame_type = 255 /* full_frame */
    offset_delta = 22
    locals = [ class Bar, class java/lang/Object ]
    stack = [ class java/lang/Throwable ]

So the same is seen here also.

    public synchronized void instanceOuter();
    descriptor: ()V
    flags: ACC_PUBLIC, ACC_SYNCHRONIZED
    Code:
    stack=3, locals=1, args_size=1
    0: getstatic     #3      // Field java/lang/System.out:Ljava/io/PrintS
    3: ldc           #11     // String Instance outer.
    5: invokevirtual #5      // Method java/io/PrintStream.println:(Ljava/
    8: new           #6      // class java/lang/UnknownError
    11: dup
    12: ldc           #7      // String TODO
    14: invokespecial #8      // Method java/lang/UnknownError."<init>":(L
    17: athrow
    LineNumberTable:
    line 29: 0
    line 30: 8

I can either wrap it at run-time or I can just generate it as it. If I do have
it then I will need a global exception handler so monitorexit is called at
the very end of a method.

## 22:14

Would have been better if the language standard just had synchronized compiled
the same as `synchronized (this)`.