softfp broken in gnu-classpath on ARM EABI? Was: Re: [kaffe] ARM EABI fixed cache_flush but broken VMDouble.toString

[Steven Newbury]

--- Steven Newbury <s_j_newbury at yahoo.co.uk> wrote:


> zaurus java # java HelloWorldApp       
> Internal error: caught an unexpected exception.
> Please check your CLASSPATH and your installation.
> java/lang/UnsatisfiedLinkError: Failed to locate native function:      
> java/lang/VMDouble.toString(DZ)Ljava/lang/String;
>    at java.lang.ClassLoader.getSystemClassLoader (ClassLoader.java:799)
> Aborted
> 
> I'm working against a checkout of the current kaffe CVS.
> 
> My target machine is a PXA270 with a iwmmxt native gcc-4.3 toolchain (using
> -ftree-vectorize), so softfloat only.  Disassembly of libkaffevm-1.1.8-pre.so
> shows the functions handling doubles etc using 64bit iWMMXt registers which
> is
> nice.
> 
> I'm going to do more digging and see if I can figure it out.
> 

I've been doing more testing.  I built jamvm and while it runs I get:
import java.io.*;

public class FloatTest
{
  public static void main (String[]args)
  {
    System.err.println ((float) 100000000);
  }
}

zaurus bugs # java FloatTest
NaN

While with kaffe I get:
zaurus bugs # java FloatTest
Internal error: caught an unexpected exception.
Please check your CLASSPATH and your installation.
java/lang/UnsatisfiedLinkError: Failed to locate native function:      
java/lang/VMDouble.toString(DZ)Ljava/lang/String;
   at java.lang.ClassLoader.getSystemClassLoader (ClassLoader.java:799)
Aborted

...or sometimes...

zaurus bugs # java FloatTest
Illegal instruction

Unfortunately when I tried to use KAFFE_DEBUG=gdb

zaurus bugs # KAFFE_DEBUG=gdb java FloatTest
GNU gdb 6.6
Copyright (C) 2006 Free Software Foundation, Inc.
GDB is free software, covered by the GNU General Public License, and you are
welcome to change it and/or distribute copies of it under certain conditions.
Type "show copying" to see the conditions.
There is absolutely no warranty for GDB.  Type "show warranty" for details.
This GDB was configured as "arm-iwmmxt-linux-gnueabi"...
(no debugging symbols found)
Using host libthread_db library "/lib/libthread_db.so.1".
(gdb) run
Starting program: /usr/opt/kaffe-9999/jre/bin/kaffe-bin FloatTest
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
(no debugging symbols found)
[Thread debugging using libthread_db enabled]
[New Thread 1073873152 (LWP 21821)]

Program received signal SIGSEGV, Segmentation fault.
[Switching to Thread 1073873152 (LWP 21821)]
0x4008cba8 in KaffePThread_detectStackBoundaries () from
/opt/kaffe-9999/jre/lib/arm/libkaffevm-1.1.8-pre.so
(gdb) cont
Continuing.

Program received signal SIGILL, Illegal instruction.
0x0018ef54 in ?? ()
(gdb) bt
#0  0x0018ef54 in ?? ()
(gdb) disassemble
No function contains program counter for selected frame.
(gdb)

I'm using Gentoo portage and it strips the binaries by default, I'm going to
try it without and see if it makes a difference.

I'm leaning towards a classpath bug, I'm just a bit surprised it hasn't come up
previously...???

This is an experimental toolchain, but I have built a full system with it,
including KDE(!), so while not impossible a bug there seems less likely.


Steve


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