On Thu, Oct 13, 2016 at 12:19:53PM +0200, Richard Biener wrote: > > (note 6350 6349 6351 (var_location temp (nil)) NOTE_INSN_VAR_LOCATION) > > (note 6351 6350 6352 (var_location temp$low (mem/c:DI (plus:SI (reg/f:SI 30 > > %fp) > > (const_int -112 [0xffffffffffffff90])) [10 MEM[(struct cpp_num > > *)&result + 8B]+0 S8 A64])) NOTE_INSN_VAR_LOCATION) > > (note 6352 6351 6353 (var_location temp$8 (nil)) NOTE_INSN_VAR_LOCATION) > > [...] > > (code_label 2091 6355 2092 79 912 "" [1 uses]) > > (note 2092 2091 5271 79 [bb 79] NOTE_INSN_BASIC_BLOCK) > > > > is interpreted differently from: > > > > (note 6350 6349 6351 (var_location temp (nil)) NOTE_INSN_VAR_LOCATION) > > (note 6351 6350 6352 (var_location temp$8 (nil)) NOTE_INSN_VAR_LOCATION) > > (note 6352 6351 6353 (var_location temp$low (mem/c:DI (plus:SI (reg/f:SI 30 > > %fp) > > (const_int -112 [0xffffffffffffff90])) [10 MEM[(struct cpp_num > > *)&result + 8B]+0 S8 A64])) NOTE_INSN_VAR_LOCATION) > > [...] > > (note 2092 2091 5271 79 [bb 79] NOTE_INSN_BASIC_BLOCK) > > > > @@ -32608,6 +32608,17 @@ > > .uleb128 0x8 > > .byte 0x93 ! DW_OP_piece > > .uleb128 0x8 > > + .uaword .LLVL592-.LLtext0 ! Location list begin address > > (*.LLLST153) > > + .uaword .LLVL597-.LLtext0 ! Location list end address > > (*.LLLST153) > > + .uahalf 0x9 ! Location expression size > > + .byte 0x93 ! DW_OP_piece > > + .uleb128 0x8 > > + .byte 0x8e ! DW_OP_breg30 > > + .sleb128 -112 > > + .byte 0x93 ! DW_OP_piece > > + .uleb128 0x8 > > + .byte 0x93 ! DW_OP_piece > > + .uleb128 0x8 > > .uaword .LLVL695-.LLtext0 ! Location list begin address > > (*.LLLST153) > > .uaword .LLVL696-.LLtext0 ! Location list end address > > (*.LLLST153) > > .uahalf 0xe ! Location expression size > > > > probably because the non-null location comes last in the second case. > > Definitely looks like a bug to me. Can you open a PR for this so it doesn't > get > lost?
I guess it depends on whether temp$8 and temp$low overlap or not. If they overlap, then the different orders of course matter and should matter. Jakub