re PR debug/41343 (sysdeps/ieee754/dbl-64/dosincos.c from glibc causes excessive memory use)

gcc/ChangeLog:
PR debug/41343
PR debug/41447
PR debug/41264
PR debug/41338
* tree.def (DEBUG_EXPR_DECL): New.
* rtl.def (DEBUG_EXPR): New.
* gengtype.c (adjust_field_rtx_def): Handle it.
* tree-ssa.c (propagate_var_def_into_debug_stmts): Rename to...
(insert_debug_temp_for_var_def): ... this.  Drop support for
moving.  Take iterator for def stmt; insert debug stmt before it.
Scan early for use count and kind in debug stmts.
(propagate_defs_into_debug_stmts): Rename to...
(insert_debug_temps_for_defs): ... this.  Likewise.
* tree.h (DEBUG_TEMP_UID): New.
* tree.c (next_debug_decl_uid): New.
(make_node_stat): Count debug decls separately.
(copy_node_stat): Likewise.
* cfgexpand.c (expand_debug_expr): Handle DEBUG_EXPR_DECL.
* var-tracking.c (dv_is_decl_p): Recognize it.
(VALUE_RECURSED_INTO): Apply to DEBUG_EXPRs too.
(track_expr_p): Track expanded DEBUG_EXPR_DECLs.
(vt_expand_loc_callback): Expand DEBUG_EXPRs.
(emit_note_insn_var_location): Don't emit notes for DEBUG_EXPR_DECLs.
* cselib.c (rtx_equal_for_cselib_p): Handle DEBUG_EXPR.
(cselib_hash_rtx): Likewise.
(cselib_expand_value_rtx_1): Use callback for DEBUG_EXPR.
* tree-ssa-operands.c (get_expr_operands): Skip DEBUG_EXPR_DECLs in
debug bind stmts.
* emit-rtl.c (verify_rtx_sharing): Handle DEBUG_EXPR and VALUE.
(copy_rtx_if_shared_1, reset_used_flags, set_used_flags): Likewise.
* rtl.c (copy_rtx): Likewise.
(rtx_equal_p_cb, rtx_equal_p): Handle DEBUG_EXPR.
* print-rtl.c (print_rtx): Likewise.
* sched-vis.c (print_value): Likewise.
(print_insn): Handle DEBUG_EXPR_DECL.
* tree-dump.c (dequeue_and_dump): Likewise.
* tree-pretty-print.c (dump_decl_name, dump_generic_node): Likewise.
* gimple-iterator (gsi_replace): Check for same lhs.
(gsi_remove): Insert debug temps.
* tree-ssa-loop-im.c (rewrite_reciprocal): Replace with same lhs.
(move_computations_stmt): Drop explicit propagation into debug stmts.
(rewrite_bittest): Likewise.  Use gsi_remove for propagation.
* tree-ssa-reassoc.c (rewrite_expr_tree, linearize_expr): Likewise.
* tree-ssa-sink.c (statement_sink_location): Likewise.
* tree-ssa-forwprop (forward_propagate_addr_expr): Likewise.
* tree-ssanames.c (release_ssa_name): Adjust for rename.
* tree-flow.h: Likewise.
* tree-ssa-dce.c (mark_stmt_if_obviously_necessary): Don't mark
debug temps without values.
(eliminate_unnecessary_stmts): Don't discard just-inserted
debug stmts.
gcc/testsuite/ChangeLog:
PR debug/41343
PR debug/41447
PR debug/41264
PR debug/41338
* gcc.dg/guality/pr41447-1.c: New.
* gcc.dg/debug/pr41264-1.c: New.
* gcc.dg/debug/pr41343-1.c: New.

From-SVN: r152681

1 files changed, 14 insertions, 6 deletions

diff --git a/gcc/tree-ssa-loop-im.c b/gcc/tree-ssa-loop-im.c
index 7382494..6c6a9f1 100644
--- a/gcc/tree-ssa-loop-im.c
+++ b/gcc/tree-ssa-loop-im.c
@@ -764,6 +764,7 @@ rewrite_reciprocal (gimple_stmt_iterator *bsi)
   gimple stmt, stmt1, stmt2;
   tree var, name, lhs, type;
   tree real_one;
+  gimple_stmt_iterator gsi;
 
   stmt = gsi_stmt (*bsi);
   lhs = gimple_assign_lhs (stmt);
@@ -798,8 +799,9 @@ rewrite_reciprocal (gimple_stmt_iterator *bsi)
   /* Replace division stmt with reciprocal and multiply stmts.
      The multiply stmt is not invariant, so update iterator
      and avoid rescanning.  */
-  gsi_replace (bsi, stmt1, true);
-  gsi_insert_after (bsi, stmt2, GSI_NEW_STMT);
+  gsi = *bsi;
+  gsi_insert_before (bsi, stmt1, GSI_NEW_STMT);
+  gsi_replace (&gsi, stmt2, true);
 
   /* Continue processing with invariant reciprocal statement.  */
   return stmt1;
@@ -858,6 +860,8 @@ rewrite_bittest (gimple_stmt_iterator *bsi)
   if (outermost_invariant_loop (b, loop_containing_stmt (stmt1)) != NULL
       && outermost_invariant_loop (a, loop_containing_stmt (stmt1)) == NULL)
     {
+      gimple_stmt_iterator rsi;
+
       /* 1 << B */
       var = create_tmp_var (TREE_TYPE (a), "shifttmp");
       add_referenced_var (var);
@@ -878,9 +882,14 @@ rewrite_bittest (gimple_stmt_iterator *bsi)
       SET_USE (use, name);
       gimple_cond_set_rhs (use_stmt, build_int_cst_type (TREE_TYPE (name), 0));
 
-      gsi_insert_before (bsi, stmt1, GSI_SAME_STMT);
-      propagate_defs_into_debug_stmts (gsi_stmt (*bsi), NULL, NULL);
-      gsi_replace (bsi, stmt2, true);
+      /* Don't use gsi_replace here, none of the new assignments sets
+	 the variable originally set in stmt.  Move bsi to stmt1, and
+	 then remove the original stmt, so that we get a chance to
+	 retain debug info for it.  */
+      rsi = *bsi;
+      gsi_insert_before (bsi, stmt1, GSI_NEW_STMT);
+      gsi_insert_before (&rsi, stmt2, GSI_SAME_STMT);
+      gsi_remove (&rsi, true);
 
       return stmt1;
     }
@@ -1060,7 +1069,6 @@ move_computations_stmt (struct dom_walk_data *dw_data ATTRIBUTE_UNUSED,
 
       mark_virtual_ops_for_renaming (stmt);
       gsi_insert_on_edge (loop_preheader_edge (level), stmt);
-      propagate_defs_into_debug_stmts (gsi_stmt (bsi), NULL, NULL);
       gsi_remove (&bsi, false);
     }
 }