[M3devel] FW: bad code on PPC_LINUX?

Jay jayk123 at hotmail.com
Thu Jan 10 10:28:31 CET 2008


My emails keep getting truncated for some reason.. :(


> From: jayk123 at hotmail.com
> To: m3devel at elegosoft.com
> Subject: bad code on PPC_LINUX?
> Date: Thu, 10 Jan 2008 07:11:11 +0000
> 
> 
> Something is screwy I think.
> My gdb skills are um not good.
> 
> On PPC_LINUX.
> 
> /dev2/cm3/m3-sys/cm3/src/Utils.m3
> 
> PROCEDURE WriteFile (file: TEXT;  proc: Emitter;  append := FALSE) =
>   VAR wr: Wr.T;
>   BEGIN
>     IF (append)
>       THEN wr := AppendWriter (file, fatal := TRUE);
>       ELSE wr := OpenWriter (file, fatal := TRUE);
>     END;
>     TRY           (* line 78 *)
>       TRY
>         proc (wr);
>       EXCEPT
>       | Wr.Failure (ec) =>
>           Msg.FatalError (ec, "write failed on ", file);
>       | Thread.Alerted =>
>           Msg.FatalError (NIL, "interrupted while writing ", file);
>       END;
>     FINALLY
>       CloseWriter (wr, file);
>     END;
>   END WriteFile;
> 
> I get a SEGV on line 78.
> 
> I'm willing to believe, sadly, that some of these huge offsets
> are the price of TRY and saving the register context on anything
> other than x86 (for registers that aren't even used by the function?),
> however it crashes just after the call and notice there the huge 32k offset.
> 
> And really? A 720 byte frame for any function with a TRY on PowerPC?
> Really?
> I guess I should look at what PPC_DARWIN does.
> 
> If someone can give me a quick run down on PowerPC ABI, thanks.
> I'll search the web. Or maybe check my Mac docs.
> register 0 is 0 or general purpose?
> Stack is register ?
> I know that return address is in the link register.
> bl is branch and link -- call -- jump and save pc in link register.
> 
> The code is:
> (gdb) disassemble
> Dump of assembler code for function Utils__WriteFile:
> 0x10024fbc :        stwu    r1,-720(r1)
> 0x10024fc0 :        mflr    r0
> 0x10024fc4 :        mfcr    r12
> 0x10024fc8 :       stfd    f14,576(r1)
> 0x10024fcc :       stfd    f15,584(r1)
> 0x10024fd0 :       stfd    f16,592(r1)
> 0x10024fd4 :       stfd    f17,600(r1)
> 0x10024fd8 :       stfd    f18,608(r1)
> 0x10024fdc :       stfd    f19,616(r1)
> 0x10024fe0 :       stfd    f20,624(r1)
> 0x10024fe4 :       stfd    f21,632(r1)
> 0x10024fe8 :       stfd    f22,640(r1)
> 0x10024fec :       stfd    f23,648(r1)
> 0x10024ff0 :       stfd    f24,656(r1)
> 0x10024ff4 :       stfd    f25,664(r1)
> 0x10024ff8 :       stfd    f26,672(r1)
> 0x10024ffc :       stfd    f27,680(r1)
> 0x10025000 :       stfd    f28,688(r1)
> 0x10025004 :       stfd    f29,696(r1)
> 0x10025008 :       stfd    f30,704(r1)
> 0x1002500c :       stfd    f31,712(r1)
> 0x10025010 :       stw     r14,504(r1)
> 0x10025014 :       stw     r15,508(r1)
> 0x10025018 :       stw     r16,512(r1)
> 0x1002501c :       stw     r17,516(r1)
> 0x10025020 :      stw     r18,520(r1)
> 0x10025024 :      stw     r19,524(r1)
> 0x10025028 :      stw     r20,528(r1)
> 0x1002502c :      stw     r21,532(r1)
> ---Type  to continue, or q  to quit---
> 0x10025030 :      stw     r22,536(r1)
> 0x10025034 :      stw     r23,540(r1)
> 0x10025038 :      stw     r24,544(r1)
> 0x1002503c :      stw     r25,548(r1)
> 0x10025040 :      stw     r26,552(r1)
> 0x10025044 :      stw     r27,556(r1)
> 0x10025048 :      stw     r28,560(r1)
> 0x1002504c :      stw     r29,564(r1)
> 0x10025050 :      stw     r30,568(r1)
> 0x10025054 :      stw     r31,572(r1)
> 0x10025058 :      stw     r0,724(r1)
> 0x1002505c :      stw     r12,500(r1)
> 0x10025060 :      mr      r31,r1
> 0x10025064 :      bl      0x10025068 
> 0x10025068 :      mflr    r30
> 0x1002506c :      lwz     r0,-176(r30)
> 0x10025070 :      add     r30,r0,r30
> 0x10025074 :      stw     r3,8(r31)
> 0x10025078 :      stw     r4,12(r31)
> 0x1002507c :      mr      r0,r5
> 0x10025080 :      stb     r0,16(r31)
> 0x10025084 :      li      r0,0
> 0x10025088 :      stw     r0,20(r31)
> 0x1002508c :      lbz     r0,16(r31)
> 0x10025090 :      clrlwi  r0,r0,24
> 0x10025094 :      cmpwi   r0,0
> 0x10025098 :      beq-    0x100250b8 
> 0x1002509c :      lwz     r3,8(r31)
> 0x100250a0 :      li      r4,1
> 0x100250a4 :      bl      0x100248a4 
> ---Type  to continue, or q  to quit---
> 0x100250a8 :      stw     r3,476(r31)
> 0x100250ac :      lwz     r9,476(r31)
> 0x100250b0 :      stw     r9,20(r31)
> 0x100250b4 :      b       0x100250d0 
> 0x100250b8 :      lwz     r3,8(r31)
> 0x100250bc :      li      r4,1
> 0x100250c0 :      bl      0x10024658 
> 0x100250c4 :      stw     r3,476(r31)
> 0x100250c8 :      lwz     r9,476(r31)
> 0x100250cc :      stw     r9,20(r31)
> 
>  ** here I believe ** 
> 
> 0x100250d0 :      lwz     r0,-32760(r30)
> 0x100250d4 :      stw     r0,32(r31)
> 0x100250d8 :      addi    r0,r31,8
> 0x100250dc :      stw     r0,36(r31)
> 0x100250e0 :      li      r0,3
> 0x100250e4 :      stw     r0,28(r31)
> 0x100250e8 :      lwz     r9,-32764(r30)
> 0x100250ec :      lwz     r0,0(r9)
> 0x100250f0 :      stw     r0,24(r31)
> 0x100250f4 :      lwz     r9,-32764(r30)
> 0x100250f8 :      addi    r0,r31,24
> 0x100250fc :      stw     r0,0(r9)
> 0x10025100 :      lwz     r9,-32768(r30)
> 0x10025104 :      addi    r0,r9,76
> 0x10025108 :      stw     r0,64(r31)
> 0x1002510c :      li      r0,0
> 0x10025110 :      stw     r0,60(r31)
> 0x10025114 :      lwz     r9,-32764(r30)
> 0x10025118 :      lwz     r0,0(r9)
> 0x1002511c :      stw     r0,56(r31)
> ---Type  to continue, or q  to quit---
> 0x10025120 :      lwz     r9,-32764(r30)
> 0x10025124 :      addi    r0,r31,56
> 0x10025128 :      stw     r0,0(r9)
> 0x1002512c :      addi    r9,r31,56
> 0x10025130 :      addi    r0,r9,48
> 0x10025134 :      mr      r3,r0
> 0x10025138 :      bl      0x101bbf28 
> 0x1002513c :      mr      r0,r3
> 0x10025140 :      cmpwi   r0,0
> 0x10025144 :      bne-    0x100251ac 
> 0x10025148 :      lwz     r9,12(r31)
> 0x1002514c :      stw     r9,476(r31)
> 0x10025150 :      lwz     r9,476(r31)
> 0x10025154 :      cmpwi   r9,0
> 0x10025158 :      beq-    0x10025188 
> 0x1002515c :      lwz     r9,476(r31)
> 0x10025160 :      lwz     r0,0(r9)
> 0x10025164 :      li      r9,-1
> 0x10025168 :      cmpw    r0,r9
> 0x1002516c :      bne-    0x10025188 
> 0x10025170 :      lwz     r9,476(r31)
> 0x10025174 :      lwz     r9,8(r9)
> 0x10025178 :      stw     r9,480(r31)
> 0x1002517c :      lwz     r9,476(r31)
> 0x10025180 :      lwz     r9,4(r9)
> 0x10025184 :      stw     r9,476(r31)
> 0x10025188 :      lwz     r11,480(r31)
> 0x1002518c :      lwz     r3,20(r31)
> 0x10025190 :      lwz     r0,476(r31)
> 0x10025194 :      mtlr    r0
> ---Type  to continue, or q  to quit---
> 0x10025198 :      blrl
> 0x1002519c :      lwz     r9,-32764(r30)
> 0x100251a0 :      lwz     r0,56(r31)
> 0x100251a4 :      stw     r0,0(r9)
> 0x100251a8 :      b       0x10025210 
> 0x100251ac :      lwz     r9,68(r31)
> 0x100251b0 :      lwz     r9,0(r9)
> 0x100251b4 :      lis     r0,-15535
> 0x100251b8 :      ori     r0,r0,42454
> 0x100251bc :      cmpw    r9,r0
> 0x100251c0 :      bne-    0x100251f0 
> 0x100251c4 :      lwz     r0,72(r31)
> 0x100251c8 :      stw     r0,472(r31)
> 0x100251cc :      lwz     r9,-32768(r30)
> 0x100251d0 :      addi    r0,r9,180
> 0x100251d4 :      lwz     r3,472(r31)
> 0x100251d8 :      mr      r4,r0
> 0x100251dc :      lwz     r5,8(r31)
> 0x100251e0 :      li      r6,0
> 0x100251e4 :      li      r7,0
> 0x100251e8 :      bl      0x10023b4c 
> 0x100251ec :      b       0x10025210 
> 0x100251f0 :      lwz     r9,-32768(r30)
> 0x100251f4 :      addi    r0,r9,212
> 0x100251f8 :      li      r3,0
> 0x100251fc :      mr      r4,r0
> 0x10025200 :      lwz     r5,8(r31)
> 0x10025204 :      li      r6,0
> 0x10025208 :      li      r7,0
> 0x1002520c :      bl      0x10023b4c 
> ---Type  to continue, or q  to quit---
> 0x10025210 :      lwz     r9,-32764(r30)
> 0x10025214 :      lwz     r0,24(r31)
> 0x10025218 :      stw     r0,0(r9)
> 0x1002521c :      addi    r11,r31,8
> 0x10025220 :      bl      0x10024f74 
> 0x10025224 :      lwz     r11,0(r1)
> 0x10025228 :      lwz     r0,4(r11)
> 0x1002522c :      lwz     r12,-220(r11)
> 0x10025230 :      mtlr    r0
> 0x10025234 :      lwz     r14,-216(r11)
> 0x10025238 :      lwz     r15,-212(r11)
> 0x1002523c :      lwz     r16,-208(r11)
> 0x10025240 :      lwz     r17,-204(r11)
> 0x10025244 :      lwz     r18,-200(r11)
> 0x10025248 :      lwz     r19,-196(r11)
> 0x1002524c :      lwz     r20,-192(r11)
> 0x10025250 :      lwz     r21,-188(r11)
> 0x10025254 :      lwz     r22,-184(r11)
> 0x10025258 :      lwz     r23,-180(r11)
> 0x1002525c :      lwz     r24,-176(r11)
> 0x10025260 :      lwz     r25,-172(r11)
> 0x10025264 :      lwz     r26,-168(r11)
> 0x10025268 :      lwz     r27,-164(r11)
> 0x1002526c :      lwz     r28,-160(r11)
> 0x10025270 :      lwz     r29,-156(r11)
> 0x10025274 :      lwz     r30,-152(r11)
> 0x10025278 :      lwz     r31,-148(r11)
> 0x1002527c :      lfd     f14,-144(r11)
> 0x10025280 :      lfd     f15,-136(r11)
> 0x10025284 :      lfd     f16,-128(r11)
> ---Type  to continue, or q  to quit---
> 0x10025288 :      lfd     f17,-120(r11)
> 0x1002528c :      lfd     f18,-112(r11)
> 0x10025290 :      lfd     f19,-104(r11)
> 0x10025294 :      lfd     f20,-96(r11)
> 0x10025298 :      lfd     f21,-88(r11)
> 0x1002529c :      lfd     f22,-80(r11)
> 0x100252a0 :      lfd     f23,-72(r11)
> 0x100252a4 :      lfd     f24,-64(r11)
> 0x100252a8 :      lfd     f25,-56(r11)
> 0x100252ac :      lfd     f26,-48(r11)
> 0x100252b0 :      lfd     f27,-40(r11)
> 0x100252b4 :      lfd     f28,-32(r11)
> 0x100252b8 :      lfd     f29,-24(r11)
> 0x100252bc :      lfd     f30,-16(r11)
> 0x100252c0 :      lfd     f31,-8(r11)
> 0x100252c4 :      mtcrf   56,r12
> 0x100252c8 :      mr      r1,r11
> 0x100252cc :      blr
> 0x100252d0 :      .long 0x24ebb0
> End of assembler dump.
> 
> 
> (gdb) bt
> #0  Utils__WriteFile (M3_Bd56fi_file=0x10277ba0, M3_DmuccK_proc=0x7fb22210,
>     M3_AicXUJ_append=0 '\0') at Utils.m3:78
> #1  0x10020a10 in Makefile__Build (M3_Bd56fi_src_dir=0x102720ec)
>     at Makefile.m3:101
> #2  0x100292d4 in Main__DoIt () at Main.m3:71
> #3  0x10029834 in Main_M3 (M3_AcxOUs_mode=1) at Main.m3:193
> #4  0x10188f9c in RTLinker__RunMainBody (M3_DUuepq_m=0x10279b28)
>     at RTLinker.m3:387
> #5  0x101880bc in RTLinker__AddUnitI (M3_DUuepq_m=0x10279b28) at RTLinker.m3:100
> #6  0x10188198 in RTLinker__AddUnit (M3_DUuepw_b=0x100297f8) at RTLinker.m3:110
> #7  0x100002ec in main (argc=1, argv=0x7fb22834, envp=0x7fb2283c) at _m3main.mc:4
> 
> I haven't yet figured out how to get gdb to show me the details of the SEGV, like what address was referenced.
> 
> I swear I think this was working better recently.
> 
> Oh, I did change something. I will try to change it back.
> I added -fPIC.
> Dynamic linking was not working and I thought that might fix it.
> I'll definitely try without it now.
> 
> Also, relevant aside -- what, if any, distributions/versions of Linux are people using on PowerPC?
> Specifically on PowerPC (to limit the religious explosion)
> I'm currently using Yellow Dog, I think 4.1, but only for Modula-3 purposes, not for anything else.
> 
> ps: I'd like a SMALL forum of SMART programmers, to discuss GENERAL programming topics.
> This is it perhaps?
> 
>  - Jay
> _________________________________________________________________
> Watch “Cause Effect,” a show about real people making a real difference.
> http://im.live.com/Messenger/IM/MTV/?source=text_watchcause

_________________________________________________________________
Make distant family not so distant with Windows Vista® + Windows Live™.
http://www.microsoft.com/windows/digitallife/keepintouch.mspx?ocid=TXT_TAGLM_CPC_VideoChat_distantfamily_012008
-------------- next part --------------
An HTML attachment was scrubbed...
URL: <http://m3lists.elegosoft.com/pipermail/m3devel/attachments/20080110/bf29ca32/attachment-0001.html>


More information about the M3devel mailing list