Re: [x86] Fix gcc.c-torture/compile/20080806-1.c failures

["H.J. Lu" <hjl dot tools at gmail dot com>]

On Mon, Nov 5, 2012 at 3:34 PM, H.J. Lu <hjl.tools@gmail.com> wrote:
> On Mon, Nov 5, 2012 at 10:56 AM, Richard Sandiford
> <rdsandiford@googlemail.com> wrote:
>> Uros Bizjak <ubizjak@gmail.com> writes:
>>> On Mon, Nov 5, 2012 at 9:30 AM, Richard Sandiford
>>> <rdsandiford@googlemail.com> wrote:
>>>> gcc/
>>>>         PR target/55204
>>>>         * config/i386/i386.c (ix86_address_subreg_operand): Remove stack
>>>>         pointer check.
>>>>         (print_reg): Use true_regnum rather than REGNO.
>>>>         (ix86_print_operand_address): Remove SUBREG handling.
>>>
>>> The patch is OK for mainline and 4.7, if it passes H.J.'s tests with
>>> -maddress-mode={short,long} on x32.
>>>
>>>> +  unsigned int regno = true_regnum (x);
>>>
>>> I'd rather see the declaration at the beginning of the function.
>>
>> OK, thanks, applied to both with that change.
>>
>> Richard
>
>
> On 4.7 branch, this failed to build x32 run-time library:
>
> /tmp/ccID3vr6.s: Assembler messages:
> /tmp/ccID3vr6.s:2788: Error: bad register name `%rr15'
>
> There is an extra 'r' in register name.
>
> --
> H.J.

I think this is a real bug:

    case 8:
    case 4:
    case 12:
      if (! ANY_FP_REG_P (x))
        putc (code == 8 && TARGET_64BIT ? 'r' : 'e', file);
      /* FALLTHRU */
    case 16:
    case 2:
    normal:
      reg = hi_reg_name[regno];
      break;

hi_reg_name has

#define HI_REGISTER_NAMES                                               \
{"ax","dx","cx","bx","si","di","bp","sp",                               \
 "st","st(1)","st(2)","st(3)","st(4)","st(5)","st(6)","st(7)",          \
 "argp", "flags", "fpsr", "fpcr", "frame",                              \
 "xmm0","xmm1","xmm2","xmm3","xmm4","xmm5","xmm6","xmm7",               \
 "mm0", "mm1", "mm2", "mm3", "mm4", "mm5", "mm6", "mm7",                \
 "r8", "r9", "r10", "r11", "r12", "r13", "r14", "r15",                  \
 "xmm8", "xmm9", "xmm10", "xmm11", "xmm12", "xmm13", "xmm14", "xmm15"}

If we ever use r8 to r15, we print wrong register name.  We should
catch it with

  /* Irritatingly, AMD extended registers use different naming convention
     from the normal registers: "r%d[bwd]"  */
  if (REX_INT_REG_P (x))

But it doesn't work with subreg change.   I am testing this

diff --git a/gcc/config/i386/i386.c b/gcc/config/i386/i386.c
index 37498ef..b42870f 100644
--- a/gcc/config/i386/i386.c
+++ b/gcc/config/i386/i386.c
@@ -13729,7 +13729,7 @@ print_reg (rtx x, int code, FILE *file)

   /* Irritatingly, AMD extended registers use different naming convention
      from the normal registers: "r%d[bwd]"  */
-  if (REX_INT_REG_P (x))
+  if (REX_INT_REGNO_P (regno))
     {
       gcc_assert (TARGET_64BIT);
       putc ('r', file);

I will check it into trunk and 4.7 branch if test passes.

Thanks.


-- 
H.J.