https://gcc.gnu.org/bugzilla/show_bug.cgi?id=84620
Jakub Jelinek <jakub at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jakub at gcc dot gnu.org
--- Comment #2 from Jakub Jelinek <jakub at gcc dot gnu.org> ---
Comment on attachment 43539
--> https://gcc.gnu.org/bugzilla/attachment.cgi?id=43539
candidate patch
>[IEPM] [PR debug/84620] use constant form for DW_AT_GNU_entry_view
>
>When outputting entry views in symbolic mode, we used to use a lbl_id,
>but was output as an addr, perhaps even in an indirect one, which is
>all excessive and undesirable for a small assembler-computed constant.
>Introduce a new value class for symbolic views, so that we can output
>the labels as constant data, using small forms that should suffice for
>any symbolic views. Ideally, we'd use uleb128, but then the compiler
>would have to defer .debug_info offset computation to the assembler: a
>symbolic uleb128 assembler constant in an attribute is not something
>GCC can deal with ATM.
>
>for gcc/ChangeLog
>
> PR debug/84620
> * dwarf2out.h (dw_val_class): Add dw_val_class_symview.
> (dw_val_node): Add val_symbolic_view.
> * dwarf2out.c (dw_val_equal_p): Handle symview.
> (add_AT_symview): New.
> (print_dw_val): Handle symview.
> (attr_checksum, attr_checksum_ordered): Likewise.
> (same_dw_val_p, size_of_die): Likewise.
> (value_format, output_die): Likewise.
> (add_high_low_attributes): Use add_AT_symview for entry_view.
>---
> gcc/dwarf2out.c | 40 +++++++++++++++++++++++++++++++++++++++-
> gcc/dwarf2out.h | 4 +++-
> 2 files changed, 42 insertions(+), 2 deletions(-)
>
>diff --git a/gcc/dwarf2out.c b/gcc/dwarf2out.c
>index 41bb11558f69..b52edee845f2 100644
>--- a/gcc/dwarf2out.c
>+++ b/gcc/dwarf2out.c
>@@ -1434,6 +1434,8 @@ dw_val_equal_p (dw_val_node *a, dw_val_node *b)
> return a->v.val_die_ref.die == b->v.val_die_ref.die;
> case dw_val_class_fde_ref:
> return a->v.val_fde_index == b->v.val_fde_index;
>+ case dw_val_class_symview:
>+ return strcmp (a->v.val_symbolic_view, b->v.val_symbolic_view) == 0;
> case dw_val_class_lbl_id:
> case dw_val_class_lineptr:
> case dw_val_class_macptr:
>@@ -3600,6 +3602,7 @@ static addr_table_entry *add_addr_table_entry (void *,
>enum ate_kind);
> static void remove_addr_table_entry (addr_table_entry *);
> static void add_AT_addr (dw_die_ref, enum dwarf_attribute, rtx, bool);
> static inline rtx AT_addr (dw_attr_node *);
>+static void add_AT_symview (dw_die_ref, enum dwarf_attribute, const char *);
> static void add_AT_lbl_id (dw_die_ref, enum dwarf_attribute, const char *);
> static void add_AT_lineptr (dw_die_ref, enum dwarf_attribute, const char *);
> static void add_AT_macptr (dw_die_ref, enum dwarf_attribute, const char *);
>@@ -5114,6 +5117,21 @@ add_AT_vms_delta (dw_die_ref die, enum dwarf_attribute
>attr_kind,
> add_dwarf_attr (die, &attr);
> }
>
>+/* Add a symbolic view identifier attribute value to a DIE. */
>+
>+static inline void
>+add_AT_symview (dw_die_ref die, enum dwarf_attribute attr_kind,
>+ const char *view_label)
>+{
>+ dw_attr_node attr;
>+
>+ attr.dw_attr = attr_kind;
>+ attr.dw_attr_val.val_class = dw_val_class_symview;
>+ attr.dw_attr_val.val_entry = NULL;
>+ attr.dw_attr_val.v.val_symbolic_view = xstrdup (view_label);
>+ add_dwarf_attr (die, &attr);
>+}
>+
> /* Add a label identifier attribute value to a DIE. */
>
> static inline void
>@@ -6457,6 +6475,9 @@ print_dw_val (dw_val_node *val, bool recurse, FILE
>*outfile)
> fprintf (outfile, "delta: @slotcount(%s-%s)",
> val->v.val_vms_delta.lbl2, val->v.val_vms_delta.lbl1);
> break;
>+ case dw_val_class_symview:
>+ fprintf (outfile, "view: %s", val->v.val_symbolic_view);
>+ break;
> case dw_val_class_lbl_id:
> case dw_val_class_lineptr:
> case dw_val_class_macptr:
>@@ -6828,6 +6849,7 @@ attr_checksum (dw_attr_node *at, struct md5_ctx *ctx,
>int *mark)
>
> case dw_val_class_fde_ref:
> case dw_val_class_vms_delta:
>+ case dw_val_class_symview:
> case dw_val_class_lbl_id:
> case dw_val_class_lineptr:
> case dw_val_class_macptr:
>@@ -7124,6 +7146,7 @@ attr_checksum_ordered (enum dwarf_tag tag, dw_attr_node
>*at,
> break;
>
> case dw_val_class_fde_ref:
>+ case dw_val_class_symview:
> case dw_val_class_lbl_id:
> case dw_val_class_lineptr:
> case dw_val_class_macptr:
>@@ -7624,6 +7647,9 @@ same_dw_val_p (const dw_val_node *v1, const dw_val_node
>*v2, int *mark)
> case dw_val_class_die_ref:
> return same_die_p (v1->v.val_die_ref.die, v2->v.val_die_ref.die, mark);
>
>+ case dw_val_class_symview:
>+ return strcmp (v1->v.val_symbolic_view, v2->v.val_symbolic_view) == 0;
>+
> case dw_val_class_fde_ref:
> case dw_val_class_vms_delta:
> case dw_val_class_lbl_id:
>@@ -9284,6 +9310,10 @@ size_of_die (dw_die_ref die)
> size += csize;
> }
> break;
>+ case dw_val_class_symview:
>+ /* FIXME: Use uleb128 rather than data2. */
>+ size += 2;
>+ break;
> case dw_val_class_const_implicit:
> case dw_val_class_unsigned_const_implicit:
> case dw_val_class_file_implicit:
>@@ -9732,6 +9762,9 @@ value_format (dw_attr_node *a)
> default:
> return DW_FORM_block1;
> }
>+ case dw_val_class_symview:
>+ /* FIXME: Use uleb128 rather than data2. */
>+ return DW_FORM_data2;
> case dw_val_class_vec:
> switch (constant_size (a->dw_attr_val.v.val_vec.length
> * a->dw_attr_val.v.val_vec.elt_size))
>@@ -10497,6 +10530,11 @@ output_die (dw_die_ref die)
> }
> break;
>
>+ case dw_val_class_symview:
>+ /* FIXME: Use uleb128 rather than data2. */
>+ dw2_asm_output_addr (2, a->dw_attr_val.v.val_symbolic_view, "%s",
>name);
>+ break;
>+
> case dw_val_class_const_implicit:
> if (flag_debug_asm)
> fprintf (asm_out_file, "\t\t\t%s %s ("
>@@ -23809,7 +23847,7 @@ add_high_low_attributes (tree stmt, dw_die_ref die)
> indirecting them through a table might make things
> easier, but even that would be more wasteful,
> space-wise, than what we have now. */
>- add_AT_lbl_id (die, DW_AT_GNU_entry_view, label);
>+ add_AT_symview (die, DW_AT_GNU_entry_view, label);
> }
> }
>
>diff --git a/gcc/dwarf2out.h b/gcc/dwarf2out.h
>index a1856a5185e2..f2240af85375 100644
>--- a/gcc/dwarf2out.h
>+++ b/gcc/dwarf2out.h
>@@ -161,7 +161,8 @@ enum dw_val_class
> dw_val_class_const_implicit,
> dw_val_class_unsigned_const_implicit,
> dw_val_class_file_implicit,
>- dw_val_class_view_list
>+ dw_val_class_view_list,
>+ dw_val_class_symview
> };
>
> /* Describe a floating point constant value, or a vector constant value. */
>@@ -209,6 +210,7 @@ struct GTY(()) dw_val_node {
> HOST_WIDE_INT GTY ((default)) val_int;
> unsigned HOST_WIDE_INT
> GTY ((tag ("dw_val_class_unsigned_const"))) val_unsigned;
>+ char * GTY ((tag ("dw_val_class_symview"))) val_symbolic_view;
> double_int GTY ((tag ("dw_val_class_const_double"))) val_double;
> wide_int_ptr GTY ((tag ("dw_val_class_wide_int"))) val_wide;
> dw_vec_const GTY ((tag ("dw_val_class_vec"))) val_vec;
