PPC64 Compiler bug !!

[linas at austin.ibm.com]

My apologies in advance for the hallucinatory message to follow.

I have several PPC64 compilers that seem to have a bug in them.

Source code:


void spin_lock(int *lock);

long
linas_lock(int dev)
{
     long flags =0;

     spin_lock(&dev);
     return flags;
}

Compiler flags:  /opt/cross/bin/powerpc64-linux-gcc -c -Wa,-al linas.i

Assembly Listing:


GAS LISTING /tmp/ccOqxB1c.s                     page 1


   1                            .file   "linas.i"
   2                            .section        ".text"
   3                            .align 2
   4                            .globl linas_lock
   5                            .section        ".opd","aw"
   6                            .align 3
   7                    linas_lock:
   8 0000 00000000              .quad   .linas_lock,.TOC. at tocbase,0
   8      00000000
   8      00000000
   8      00000000
   8      00000000
   9                            .previous
  10                            .size   linas_lock,24
  11                            .type   .linas_lock, at function
  12                            .globl  .linas_lock
  13                    .linas_lock:
  14 0000 7C0802A6              mflr 0
  15 0004 FBE1FFF8              std 31,-8(1)
  16 0008 F8010010              std 0,16(1)
  17 000c F821FF71              stdu 1,-144(1)
  18 0010 7C3F0B78              mr 31,1
  19 0014 7C601B78              mr 0,3
  20 0018 901F00C0              stw 0,192(31)
  21 001c 38000000              li 0,0
  22 0020 F81F0070              std 0,112(31)
  23 0024 387F00C0              addi 3,31,192
  24 0028 48000001              bl .spin_lock
  25 002c 60000000              nop
  26 0030 C81F0070              lfd 0,112(31)
  27 0034 D81F0078              stfd 0,120(31)
  28 0038 E81F0078              ld 0,120(31)
  29 003c 7C030378              mr 3,0
  30 0040 E8210000              ld 1,0(1)
  31 0044 E8010010              ld 0,16(1)
  32 0048 7C0803A6              mtlr 0
  33 004c EBE1FFF8              ld 31,-8(1)
  34 0050 4E800020              blr
  35                    .LTlinas_lock:
  36 0054 00000000              .long 0
  37 0058 00000001              .byte 0,0,0,1,128,1,0,1
  37      80010001
  38                            .size   .linas_lock,.-.linas_lock
  39                            .ident  "GCC: (GNU) 3.2"


See line 26, 27 above: lfd, stfd !!!?? The first 6-bits of 0xc8, 0xd8 are
primary opcodes 50 and 54, load and store floating point double.

Surely when I wake up, it will be clear that this was a dream ??

--linas

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