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[RFA/pa-risc] Correct incorrect frame base


hello,

I noticed a problem trying to print the value of a variable with
a program compiled with GNAT (based on GCC 3.2.3). The problem
comes from the fact that GDB does not compute the correct frame
base. I think this is related to the fact that the function frame
is larger than usual. Here is the what the assembly code looks
like:

    _ada_dbtest
            .PROC
            .CALLINFO FRAME=18880,CALLS,SAVE_RP,ENTRY_GR=3
            .ENTRY
            stw %r2,-20(%r30)
            copy %r3,%r1
            copy %r30,%r3
            stwm %r1,8128(%r30)
            addil L'10752,%r30
            ldo R'10752(%r1),%r30


As you see, the frame size as published in the unwind record
is 18880 bytes, and the frame is setup in 3 instructions:

            stwm %r1,8128(%r30)
            addil L'10752,%r30
            ldo R'10752(%r1),%r30

Unfortunately, a little oops in prologue_inst_adjust_sp()
made it miss the second instruction:

  /* addil high21,%r1; ldo low11,(%r1),%r30)
     save high bits in save_high21 for later use.  */
  if ((inst & 0xffe00000) == 0x28200000)

There is a small confusion in the source register for the addil
instruction. The actual sequence should be

            addil high21,%r30
            ldo low11(%r1),%r30

I think the confusion comes from the fact that the result of
the sum is stored in %r1.

Anyway, I replaced r1 by r30 in the check above, and that fixed
the problem.

2004-12-31  Joel Brobecker  <brobecker@gnat.com>

        * hppa-tdep.c (prologue_inst_adjust_sp): Fix small confusion
        in register number for ldil instruction.

Tested on HP/UX 11.00, no regression.
OK to apply?
-- 
Joel

PS: I will be away for 3 weeks starting Jan 3rd, so please apply this
    change for me if approved after I leave. Thank you!

Attachment: ldil.diff
Description: Text document


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