[Vm-dev] CogVM/StackVM fail to read in image, fine on Squeak 4.2.1 MacVM

[Stefan Marr]

Hi:

On 18/07/11 15:01, Stefan Marr wrote:
>
> Hi Dave:
>
> On 18/07/11 14:34, David T. Lewis wrote:
>>
>> On Mon, Jul 18, 2011 at 02:02:10PM +0200, Stefan Marr wrote:
>>> However, now I noticed that the CogVM/StackVM crash when they are asked
>>> to load an image which is saved by our RoarVM.
>>>
>>> The Cog/StackVM fail to open it with an error in "0
>>> org.squeakfoundation.Squeak       0x00033462
>>> readImageFromFileHeapSizeStartingAt + 3058"
>>>
>>> [1] http://soft.vub.ac.be/~smarr/roarvm/squeak-saved-with-rvm.zip
> I took the standard stock Squeak 4.2 image, which is as far as I can 
> tell published as 6504.
>
> Now, I open and save it with the RoarVM, and then try to open it with 
> Stack/CogVM, which crashes.
I tried to dig into this a bit more.

The latest StackInterpreterSimulator in the image provided by Eliot on 
the Cog branch seems to read the image [1] just fine.
It seems to hang, but might also be that I am to inpatient.

Anyway, a debug build of 
http://www.squeakvm.org/unix/release/Squeak-4.4.7.2357-src.tar.gz loads 
the image, too.

The available 5.x mac releases fail to load it: http://www.squeakvm.org/mac/

So, I took the Cog branch and the CoreVM.xcodeproj and got a VM compiled:

#0  0x00104f80 in initializeInterpreter (bytesToShift=339693560) at 
/tmp/Cog/macbuild/../src/vm/gcc3x-cointerp.c:17479
     ccIndex = 0
     cct = 394155372
     classArrayClass = 401932980
     classArrayObj = 400674088
     header = 317718813
     i = 17402624
     i1 = 1
     i11 = 411556616
     i2 = 317431
     i3 = -1073746952
     i4 = 11
     index = -2
     oop = 10

#1  0x00123fc0 in readImageFromFileHeapSizeStartingAt (f=0xa064d8e0, 
desiredHeapSize=536870912, imageOffset=0) at 
/tmp/Cog/macbuild/../src/vm/gcc3x-cointerp.c:39218
#2  0x000652dc in main (argc=1, argv=0xbffff278, envp=0xbffff280) at 
/tmp/Cog/macbuild/../platforms/Mac OS/vm/sqMacMain.c:445


Where the code is:

17474                GIV(thisClassIndex) = i4;
17475            }
17476        }
17477        for (i4 = (InstanceSpecificationIndex + 1); i4 <= 
(lengthOf(classArrayObj)); i4 += 1) {
17478            oop = longAt((classArrayObj + BaseHeaderSize) + (i4 << 
ShiftForWord));
-> 17479            if ((((oop & 1) == 0)
17480 && (((((usqInt) (longAt(oop))) >> 8) & 15) >= 8))
17481 && (((lengthOf(oop)) == 5)
17482 && ((strncmp("Array", firstFixedField(oop), 5)) == 0))) {
17483                GIV(classNameIndex) = i4;
17484            }
17485        }


Any guesses what is going on here?

Thanks
Stefan