[kaffe] Kaffe JIT on Alpha

Kapil Vaswani kapil at csa.iisc.ernet.in
Tue Apr 22 12:43:02 PDT 2003

Hi Dalibor,

Thanks for your response. I actually managed to compile rt.jar on an x86 
and use it to proceed in the build. This has atleast allowed me to try 
and understand the problem.

There is something I came across during debugging the code generated by 
the JIT. Here is a sample prolog generated by the jit.

0:      lda     gp,0(pv)
4:      lda     sp,0(sp)
8:      stq     ra,0(sp)
24:     stq     fp,56(sp)
48:     lda     fp,0(sp)

My question is: shouldnt the stack pointer be decremented with the 
framesize before various registers are saved? The relevent piece of code 
I attach below seems to not update sp at all. I find this to be the case 
on mips as well. The push instructions on x86 take care of updating the 
sp there. Or am I missing something here??

        /* Calling Standard for Alpha Systems
         *    Entry Code Sequence
         * 2. If stack space is allocated (PDSC_RPD_FRAME_SIZE is not 
0), set
         *    register SP to SP - PDSC_RPD_FRAME_SIZE.
         *    After any necessary calculations and stack limit checks, this
         *    step must be completed in exactly one instruction that 
         *    SP.  This instruction must be the one specified by
         *    PDSC_RPD_SP_SET.  */

        alpha_jit_info.sp_set = CODEPC / 4;
        L->type = Lnegframe|Labsolute|Lgeneral;
        L->at = (uintp)CODEPC;
        op_lda(REG_sp, REG_sp, 0);

Thanks again....


Dalibor Topic wrote:

>Hi Kapil,
>--- Kapil Vaswani <kapil at csa.iisc.ernet.in> wrote:
>>config.frag still seems to be using libexec; wonder whats the status on 
>It should use libexc only if you say --with-libexc to ./configure.
>On a side note, last time I looked into getting kaffe to run on Alphas, I saw a
>very high number of compiler warnings. See 
>>>I'm busy dealing with non-Java, non-kaffe stuff for the next several
>>>weeks, but I'll be watching this with some interest.
>>>Note that Dalibor has been able to get the MIPS JIT under IRIX
>>>from CVS sources past the @essential files build failure by using
>>>Jikes instead of kaffe to build the class libraries. 
>>Not sure if using Jikes is an option for me. Any recourse?? I would love 
>>to get the kaffe jit going one way or the other.
>I'll make a jikes-compiled class library jar file available online and post a
>link to it. Then you can use --with-precompiled-rt-jar to tell kaffe not to
>bother compiling the class library, and concentrate on fixing the regression
>test failures.
>dalibor topic
>Do you Yahoo!?
>The New Yahoo! Search - Faster. Easier. Bingo
>kaffe mailing list
>kaffe at kaffe.org

-------------- next part --------------
An HTML attachment was scrubbed...
URL: http://kaffe.org/pipermail/kaffe/attachments/20030422/a8c28d8a/attachment-0008.htm 

More information about the kaffe mailing list