[Bug rtl-optimization/70890] [7 regression] r235660 miscompiles stage2 compiler on ia64

[schwab@linux-m68k.org]

https://gcc.gnu.org/bugzilla/show_bug.cgi?id=70890

--- Comment #2 from Andreas Schwab <schwab@linux-m68k.org> ---
The error happens here:

   0x400000000124cdd0 <+1936>:  [MMI]       adds r42=-1,r49
   0x400000000124cdd1 <+1937>:              adds r55=240,r12
   0x400000000124cdd2 <+1938>:              adds r32=16,r12;;
   0x400000000124cde0 <+1952>:  [MMI]       andcm r39=r42,r49
   0x400000000124cde1 <+1953>:              st8 [r55]=r32
   0x400000000124cde2 <+1954>:              nop.i 0x0
=> 0x400000000124cdf0 <+1968>:  [MMI]       ld8 r54=[r32];;
   0x400000000124cdf1 <+1969>:              nop.m 0x0
   0x400000000124cdf2 <+1970>:              popcnt r41=r39;;
   0x400000000124ce00 <+1984>:  [MII]       add r39=r47,r41
   0x400000000124ce01 <+1985>:              adds r47=44,r12;;
   0x400000000124ce02 <+1986>:              mov r56=r39
   0x400000000124ce10 <+2000>:  [MMB]       st4 [r47]=r39
   0x400000000124ce11 <+2001>:              nop.m 0x0
   0x400000000124ce12 <+2002>:              br.call.sptk.many
b0=0x4000000001256f00 <hash_table<uid_decl_hasher,
xcallocator>::find_with_hash(tree_node* const&, unsigned int)>;;

The marked line loads candidates, but r32 contains &t.