Hi,
the following patch fixes PR 54971 by creating extra
for-debug-statements-only declarations for parts of aggregates that
are never read and then creates debug bind statements so that the
value of the non-used part is accessible from debug info.
Bootstrapped and tested on x86_64-linux without any problems, OK for
trunk?
Thanks,
Martin
2012-10-25 Martin Jambor <mjam...@suse.cz>
PR debug/54971
* tree-sra.c (struct access): New flag grp_to_be_debug_replaced.
(dump_access): Dump the new flag.
(analyze_access_subtree): Set the new flag when appropriate.
(build_debug_ref_for_model): New function.
(create_access_replacement): Handle debug replacements differently.
(generate_subtree_copies): Handle the grp_to_be_debug_replaced flag.
(init_subtree_with_zero): Likewise.
(sra_modify_expr): Likewise.
(load_assign_lhs_subreplacements): Likewise.
(sra_modify_assign): Likewise.
*** /tmp/HYIEed_tree-sra.c Fri Oct 26 11:11:26 2012
--- gcc/tree-sra.c Fri Oct 26 00:54:18 2012
*************** struct access
*** 227,232 ****
--- 227,236 ----
/* Set when a scalar replacement should be created for this variable. */
unsigned grp_to_be_replaced : 1;
+ /* Set when we want a replacement for the sole purpose of having it in
+ generated debug statements. */
+ unsigned grp_to_be_debug_replaced : 1;
+
/* Should TREE_NO_WARNING of a replacement be set? */
unsigned grp_no_warning : 1;
*************** dump_access (FILE *f, struct access *acc
*** 390,396 ****
"grp_hint = %d, grp_covered = %d, "
"grp_unscalarizable_region = %d, grp_unscalarized_data = %d, "
"grp_partial_lhs = %d, grp_to_be_replaced = %d, "
! "grp_maybe_modified = %d, "
"grp_not_necessarilly_dereferenced = %d\n",
access->grp_read, access->grp_write, access->grp_assignment_read,
access->grp_assignment_write, access->grp_scalar_read,
--- 394,400 ----
"grp_hint = %d, grp_covered = %d, "
"grp_unscalarizable_region = %d, grp_unscalarized_data = %d, "
"grp_partial_lhs = %d, grp_to_be_replaced = %d, "
! "grp_to_be_debug_replaced = %d, grp_maybe_modified = %d, "
"grp_not_necessarilly_dereferenced = %d\n",
access->grp_read, access->grp_write, access->grp_assignment_read,
access->grp_assignment_write, access->grp_scalar_read,
*************** dump_access (FILE *f, struct access *acc
*** 398,404 ****
access->grp_hint, access->grp_covered,
access->grp_unscalarizable_region, access->grp_unscalarized_data,
access->grp_partial_lhs, access->grp_to_be_replaced,
! access->grp_maybe_modified,
access->grp_not_necessarilly_dereferenced);
else
fprintf (f, ", write = %d, grp_total_scalarization = %d, "
--- 402,408 ----
access->grp_hint, access->grp_covered,
access->grp_unscalarizable_region, access->grp_unscalarized_data,
access->grp_partial_lhs, access->grp_to_be_replaced,
! access->grp_to_be_debug_replaced, access->grp_maybe_modified,
access->grp_not_necessarilly_dereferenced);
else
fprintf (f, ", write = %d, grp_total_scalarization = %d, "
*************** build_ref_for_model (location_t loc, tre
*** 1528,1533 ****
--- 1532,1574 ----
gsi, insert_after);
}
+ /* Attempt to build a memory reference that we could but into a gimple
+ debug_bind statement. Similar to build_ref_for_model but punts if it has
to
+ create statements and return s NULL instead. This function also ignores
+ alignment issues and so its results should never end up in non-debug
+ statements. */
+
+ static tree
+ build_debug_ref_for_model (location_t loc, tree base, HOST_WIDE_INT offset,
+ struct access *model)
+ {
+ HOST_WIDE_INT base_offset;
+ tree off;
+
+ if (TREE_CODE (model->expr) == COMPONENT_REF
+ && DECL_BIT_FIELD (TREE_OPERAND (model->expr, 1)))
+ return NULL_TREE;
+
+ base = get_addr_base_and_unit_offset (base, &base_offset);
+ if (!base)
+ return NULL_TREE;
+ if (TREE_CODE (base) == MEM_REF)
+ {
+ off = build_int_cst (TREE_TYPE (TREE_OPERAND (base, 1)),
+ base_offset + offset / BITS_PER_UNIT);
+ off = int_const_binop (PLUS_EXPR, TREE_OPERAND (base, 1), off);
+ base = unshare_expr (TREE_OPERAND (base, 0));
+ }
+ else
+ {
+ off = build_int_cst (reference_alias_ptr_type (base),
+ base_offset + offset / BITS_PER_UNIT);
+ base = build_fold_addr_expr (unshare_expr (base));
+ }
+
+ return fold_build2_loc (loc, MEM_REF, model->type, base, off);
+ }
+
/* Construct a memory reference consisting of component_refs and array_refs to
a part of an aggregate *RES (which is of type TYPE). The requested part
should have type EXP_TYPE at be the given OFFSET. This function might not
*************** create_access_replacement (struct access
*** 1861,1867 ****
{
tree repl;
! repl = create_tmp_var (access->type, "SR");
if (TREE_CODE (access->type) == COMPLEX_TYPE
|| TREE_CODE (access->type) == VECTOR_TYPE)
{
--- 1902,1914 ----
{
tree repl;
! if (access->grp_to_be_debug_replaced)
! {
! repl = create_tmp_var_raw (access->type, NULL);
! DECL_CONTEXT (repl) = current_function_decl;
! }
! else
! repl = create_tmp_var (access->type, "SR");
if (TREE_CODE (access->type) == COMPLEX_TYPE
|| TREE_CODE (access->type) == VECTOR_TYPE)
{
*************** create_access_replacement (struct access
*** 1930,1941 ****
if (dump_file)
{
! fprintf (dump_file, "Created a replacement for ");
! print_generic_expr (dump_file, access->base, 0);
! fprintf (dump_file, " offset: %u, size: %u: ",
! (unsigned) access->offset, (unsigned) access->size);
! print_generic_expr (dump_file, repl, 0);
! fprintf (dump_file, "\n");
}
sra_stats.replacements++;
--- 1977,1998 ----
if (dump_file)
{
! if (access->grp_to_be_debug_replaced)
! {
! fprintf (dump_file, "Created a debug-only replacement for ");
! print_generic_expr (dump_file, access->base, 0);
! fprintf (dump_file, " offset: %u, size: %u\n",
! (unsigned) access->offset, (unsigned) access->size);
! }
! else
! {
! fprintf (dump_file, "Created a replacement for ");
! print_generic_expr (dump_file, access->base, 0);
! fprintf (dump_file, " offset: %u, size: %u: ",
! (unsigned) access->offset, (unsigned) access->size);
! print_generic_expr (dump_file, repl, 0);
! fprintf (dump_file, "\n");
! }
}
sra_stats.replacements++;
*************** analyze_access_subtree (struct access *r
*** 2144,2149 ****
--- 2201,2223 ----
}
else
{
+ if (MAY_HAVE_DEBUG_STMTS && allow_replacements
+ && scalar && !root->first_child
+ && (root->grp_scalar_write || root->grp_assignment_write))
+ {
+ gcc_checking_assert (!root->grp_scalar_read
+ && !root->grp_assignment_read);
+ root->grp_to_be_debug_replaced = 1;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ {
+ fprintf (dump_file, "Marking ");
+ print_generic_expr (dump_file, root->base, 0);
+ fprintf (dump_file, " offset: %u, size: %u ",
+ (unsigned) root->offset, (unsigned) root->size);
+ fprintf (dump_file, " to be replaced with debug statements.\n");
+ }
+ }
+
if (covered_to < limit)
hole = true;
if (scalar)
*************** generate_subtree_copies (struct access *
*** 2504,2509 ****
--- 2578,2599 ----
update_stmt (stmt);
sra_stats.subtree_copies++;
}
+ else if (write
+ && access->grp_to_be_debug_replaced
+ && (chunk_size == 0
+ || access->offset + access->size > start_offset))
+ {
+ gimple ds;
+ tree drhs = build_debug_ref_for_model (loc, agg,
+ access->offset - top_offset,
+ access);
+ ds = gimple_build_debug_bind (get_access_replacement (access),
+ drhs, gsi_stmt (*gsi));
+ if (insert_after)
+ gsi_insert_after (gsi, ds, GSI_NEW_STMT);
+ else
+ gsi_insert_before (gsi, ds, GSI_SAME_STMT);
+ }
if (access->first_child)
generate_subtree_copies (access->first_child, agg, top_offset,
*************** init_subtree_with_zero (struct access *a
*** 2540,2545 ****
--- 2630,2645 ----
update_stmt (stmt);
gimple_set_location (stmt, loc);
}
+ else if (access->grp_to_be_debug_replaced)
+ {
+ gimple ds = gimple_build_debug_bind (get_access_replacement (access),
+ build_zero_cst (access->type),
+ gsi_stmt (*gsi));
+ if (insert_after)
+ gsi_insert_after (gsi, ds, GSI_NEW_STMT);
+ else
+ gsi_insert_before (gsi, ds, GSI_SAME_STMT);
+ }
for (child = access->first_child; child; child = child->next_sibling)
init_subtree_with_zero (child, gsi, insert_after, loc);
*************** sra_modify_expr (tree *expr, gimple_stmt
*** 2646,2651 ****
--- 2746,2758 ----
*expr = repl;
sra_stats.exprs++;
}
+ else if (write && access->grp_to_be_debug_replaced)
+ {
+ gimple ds = gimple_build_debug_bind (get_access_replacement (access),
+ NULL_TREE,
+ gsi_stmt (*gsi));
+ gsi_insert_after (gsi, ds, GSI_NEW_STMT);
+ }
if (access->first_child)
{
*************** load_assign_lhs_subreplacements (struct
*** 2721,2730 ****
location_t loc = gimple_location (gsi_stmt (*old_gsi));
for (lacc = lacc->first_child; lacc; lacc = lacc->next_sibling)
{
if (lacc->grp_to_be_replaced)
{
struct access *racc;
- HOST_WIDE_INT offset = lacc->offset - left_offset + top_racc->offset;
gimple stmt;
tree rhs;
--- 2828,2838 ----
location_t loc = gimple_location (gsi_stmt (*old_gsi));
for (lacc = lacc->first_child; lacc; lacc = lacc->next_sibling)
{
+ HOST_WIDE_INT offset = lacc->offset - left_offset + top_racc->offset;
+
if (lacc->grp_to_be_replaced)
{
struct access *racc;
gimple stmt;
tree rhs;
*************** load_assign_lhs_subreplacements (struct
*** 2764,2773 ****
update_stmt (stmt);
sra_stats.subreplacements++;
}
! else if (*refreshed == SRA_UDH_NONE
! && lacc->grp_read && !lacc->grp_covered)
! *refreshed = handle_unscalarized_data_in_subtree (top_racc,
! old_gsi);
if (lacc->first_child)
load_assign_lhs_subreplacements (lacc, top_racc, left_offset,
--- 2872,2905 ----
update_stmt (stmt);
sra_stats.subreplacements++;
}
! else
! {
! if (*refreshed == SRA_UDH_NONE
! && lacc->grp_read && !lacc->grp_covered)
! *refreshed = handle_unscalarized_data_in_subtree (top_racc,
! old_gsi);
! if (lacc && lacc->grp_to_be_debug_replaced)
! {
! gimple ds;
! tree drhs;
! struct access *racc = find_access_in_subtree (top_racc, offset,
! lacc->size);
!
! if (racc && racc->grp_to_be_replaced)
! drhs = get_access_replacement (racc);
! else if (*refreshed == SRA_UDH_LEFT)
! drhs = build_debug_ref_for_model (loc, lacc->base, lacc->offset,
! lacc);
! else if (*refreshed == SRA_UDH_RIGHT)
! drhs = build_debug_ref_for_model (loc, top_racc->base, offset,
! lacc);
! else
! drhs = NULL_TREE;
! ds = gimple_build_debug_bind (get_access_replacement (lacc),
! drhs, gsi_stmt (*old_gsi));
! gsi_insert_after (new_gsi, ds, GSI_NEW_STMT);
! }
! }
if (lacc->first_child)
load_assign_lhs_subreplacements (lacc, top_racc, left_offset,
*************** sra_modify_assign (gimple *stmt, gimple_
*** 2982,2987 ****
--- 3114,3126 ----
}
}
+ if (lacc && lacc->grp_to_be_debug_replaced)
+ {
+ gimple ds = gimple_build_debug_bind (get_access_replacement (lacc),
+ unshare_expr (rhs), *stmt);
+ gsi_insert_before (gsi, ds, GSI_SAME_STMT);
+ }
+
/* From this point on, the function deals with assignments in between
aggregates when at least one has scalar reductions of some of its
components. There are three possible scenarios: Both the LHS and RHS
have
