diff options
Diffstat (limited to 'gcc/dce.c')
| -rw-r--r-- | gcc/dce.c | 44 |
1 files changed, 42 insertions, 2 deletions
@@ -493,6 +493,43 @@ remove_reg_equal_equiv_notes_for_defs (rtx insn) remove_reg_equal_equiv_notes_for_regno (DF_REF_REGNO (*def_rec)); } +/* Scan all BBs for debug insns and reset those that reference values + defined in unmarked insns. */ + +static void +reset_unmarked_insns_debug_uses (void) +{ + basic_block bb; + rtx insn, next; + + FOR_EACH_BB_REVERSE (bb) + FOR_BB_INSNS_REVERSE_SAFE (bb, insn, next) + if (DEBUG_INSN_P (insn)) + { + df_ref *use_rec; + + for (use_rec = DF_INSN_USES (insn); *use_rec; use_rec++) + { + df_ref use = *use_rec; + struct df_link *defs; + for (defs = DF_REF_CHAIN (use); defs; defs = defs->next) + { + rtx insn; + if (DF_REF_IS_ARTIFICIAL (defs->ref)) + continue; + insn = DF_REF_INSN (defs->ref); + if (!marked_insn_p (insn)) + break; + } + if (!defs) + continue; + /* ??? FIXME could we propagate the values assigned to + each of the DEFs? */ + INSN_VAR_LOCATION_LOC (insn) = gen_rtx_UNKNOWN_VAR_LOC (); + df_insn_rescan_debug_internal (insn); + } + } +} /* Delete every instruction that hasn't been marked. */ @@ -505,7 +542,7 @@ delete_unmarked_insns (void) FOR_EACH_BB_REVERSE (bb) FOR_BB_INSNS_REVERSE_SAFE (bb, insn, next) - if (INSN_P (insn)) + if (NONDEBUG_INSN_P (insn)) { /* Always delete no-op moves. */ if (noop_move_p (insn)) @@ -579,7 +616,7 @@ prescan_insns_for_dce (bool fast) FOR_EACH_BB (bb) { FOR_BB_INSNS_REVERSE_SAFE (bb, insn, prev) - if (INSN_P (insn)) + if (NONDEBUG_INSN_P (insn)) { /* Don't mark argument stores now. They will be marked if needed when the associated CALL is marked. */ @@ -713,6 +750,9 @@ rest_of_handle_ud_dce (void) } VEC_free (rtx, heap, worklist); + if (MAY_HAVE_DEBUG_INSNS) + reset_unmarked_insns_debug_uses (); + /* Before any insns are deleted, we must remove the chains since they are not bidirectional. */ df_remove_problem (df_chain); |