GCC trunk SPEC2000 performance

[law@redhat.com]

 In message <3D124416.5559DB3E@moene.indiv.nluug.nl>, Toon Moene writes:
 > Breakpoint 1, copy_rtx_and_substitute (orig=0x405856b0, map=0x85c2718,
 > for_lhs=0) at ../../combined/gcc/integrate.c:2065
 > 2065              if (REG_POINTER (map->x_regno_reg_rtx[regno]))
 > (gdb) p reload_completed
 > $1 = 0
 > (gdb) p reload_in_progress
 > $2 = 0
 > 
 > Nice try, but no cigar :-)
OK.  One theory gone.

The other possibility raised by David is that some phase of RTL generation
can turn a REG into a MEM (perhaps ADDRESSOF elimination?)

Looking at function.c I see three lines which look like:

  PUT_CODE (reg, MEM);

They appear in put_reg_into_stack, gen_mem_addressof and put_var_into_stack.

If you could put a conditional breakpoint on each of those and see if
they trigger, that would tell us beyond a reasonable doubt that MEMs
can/should appear in the register array.

I'd do this by first running without the breakpoint set.  When you get the
abort walk up the call chain until you're in copy_rtx_and_substitute
(ie the location where we checked REG_POINTER on the MEM).  print "regno".

Then install your conditional breakpoints with the following condition

reg->fld[0].rtint == <value of regno from above>

Re-run and see if any of them trigger.

jeff