Compilation failure of 20010119-1.c under hpux at -O1 and above
Mon Apr 30 13:20:00 GMT 2001
In message < 200104301940.PAA22385@hiauly1.hia.nrc.ca >you write:
> The test 20010119-1.c fails under hpux 10.20 on the 3.0 branch:
> Executing on host: /xxx/gnu/gcc-3.0/objdir/gcc/xgcc -B/xxx/gnu/gcc-3.0/objd
> ir/gcc/ /xxx/gnu/gcc-3.0/gcc/testsuite/gcc.c-torture/execute/20010119-1.c
> -w -O1 -lm -fPIC -o /xxx/gnu/gcc-3.0/objdir/gcc/testsuite/20010119-1.x1
> (timeout = 1200)
> /usr/ccs/bin/ld: Unsatisfied symbols:
> undef (code)
> It appears that this test doesn't work under hpux because the constant
> `20000' exceeds the maximum size to load in one insn. In the intial
> rtl, it is loaded in two insns using the high and lo_sum parts.
> Inspite of REG_EQUAL notes on both pseudos, the test `(a) > 20000' and
> the call to undef are not eliminated from the code. The test will pass
> if 20000 is changed to a smaller number, say 11.
> I would guess that this shows that comparisons involving two psuedo
> registers containing constants are not being eliminated. This would
> seem like a relatively important optimisation.
There's a whole rats nest of issues here. I've got a plan, but given that
this is an optimization issue and not a regression problem I'm not inclined
to spend time working on it in the short term.
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