From fdea8514208efcb6569c42f0be3129789a7c5b8e Mon Sep 17 00:00:00 2001
From: rth <rth@138bc75d-0d04-0410-961f-82ee72b054a4>
Date: Mon, 21 Nov 2005 00:51:39 +0000
Subject: [PATCH] PR 24931 * tree-sra.c (struct sra_elt): Add
all_no_warning. (struct sra_walk_fns) <use>: Add use_all argument.
(sra_walk_expr): Pass it. (sra_walk_modify_expr): Likewise.
(scalarize_ldst): Likewise. (scan_use): Update for new argument.
(mark_no_warning): New. (scalarize_use): Use it.
git-svn-id: svn+ssh://gcc.gnu.org/svn/gcc/trunk@107271 138bc75d-0d04-0410-961f-82ee72b054a4
---
gcc/ChangeLog | 12 +++++++++
gcc/testsuite/gcc.dg/uninit-14.c | 20 ++++++++++++++
gcc/tree-sra.c | 45 +++++++++++++++++++++++++-------
3 files changed, 68 insertions(+), 9 deletions(-)
create mode 100644 gcc/testsuite/gcc.dg/uninit-14.c
diff --git a/gcc/ChangeLog b/gcc/ChangeLog
index b3ab01ee7666..765291e4ae64 100644
--- a/gcc/ChangeLog
+++ b/gcc/ChangeLog
@@ -1,3 +1,15 @@
+2005-11-20 Richard Henderson <rth@redhat.com>
+
+ PR 24931
+ * tree-sra.c (struct sra_elt): Add all_no_warning.
+ (struct sra_walk_fns) <use>: Add use_all argument.
+ (sra_walk_expr): Pass it.
+ (sra_walk_modify_expr): Likewise.
+ (scalarize_ldst): Likewise.
+ (scan_use): Update for new argument.
+ (mark_no_warning): New.
+ (scalarize_use): Use it.
+
2005-11-20 Bernd Schmidt <bernd.schmidt@analog.com>
* expr.c (expand_expr_real): Use usmul_optab for widening
diff --git a/gcc/testsuite/gcc.dg/uninit-14.c b/gcc/testsuite/gcc.dg/uninit-14.c
new file mode 100644
index 000000000000..41b4f622ae54
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/uninit-14.c
@@ -0,0 +1,20 @@
+/* PR 24931 */
+/* { dg-do compile } */
+/* { dg-options "-O -Wuninitialized" } */
+
+struct p {
+ short x, y;
+};
+
+struct s {
+ int i;
+ struct p p;
+};
+
+struct s f()
+{
+ struct s s;
+ s.p = (struct p){};
+ s.i = (s.p.x || s.p.y);
+ return s;
+}
diff --git a/gcc/tree-sra.c b/gcc/tree-sra.c
index 940f7a97dfb1..c25632020ea5 100644
--- a/gcc/tree-sra.c
+++ b/gcc/tree-sra.c
@@ -127,6 +127,9 @@ struct sra_elt
should happen via memcpy and not per-element. */
bool use_block_copy;
+ /* True if everything under this element has been marked TREE_NO_WARNING. */
+ bool all_no_warning;
+
/* A flag for use with/after random access traversals. */
bool visited;
};
@@ -598,9 +601,10 @@ struct sra_walk_fns
/* Invoked when ELT is required as a unit. Note that ELT might refer to
a leaf node, in which case this is a simple scalar reference. *EXPR_P
points to the location of the expression. IS_OUTPUT is true if this
- is a left-hand-side reference. */
+ is a left-hand-side reference. USE_ALL is true if we saw something we
+ couldn't quite identify and had to force the use of the entire object. */
void (*use) (struct sra_elt *elt, tree *expr_p,
- block_stmt_iterator *bsi, bool is_output);
+ block_stmt_iterator *bsi, bool is_output, bool use_all);
/* Invoked when we have a copy between two scalarizable references. */
void (*copy) (struct sra_elt *lhs_elt, struct sra_elt *rhs_elt,
@@ -654,6 +658,7 @@ sra_walk_expr (tree *expr_p, block_stmt_iterator *bsi, bool is_output,
tree expr = *expr_p;
tree inner = expr;
bool disable_scalarization = false;
+ bool use_all_p = false;
/* We're looking to collect a reference expression between EXPR and INNER,
such that INNER is a scalarizable decl and all other nodes through EXPR
@@ -674,7 +679,7 @@ sra_walk_expr (tree *expr_p, block_stmt_iterator *bsi, bool is_output,
if (disable_scalarization)
elt->cannot_scalarize = true;
else
- fns->use (elt, expr_p, bsi, is_output);
+ fns->use (elt, expr_p, bsi, is_output, use_all_p);
}
return;
@@ -742,6 +747,7 @@ sra_walk_expr (tree *expr_p, block_stmt_iterator *bsi, bool is_output,
use_all:
expr_p = &TREE_OPERAND (inner, 0);
inner = expr = *expr_p;
+ use_all_p = true;
break;
default:
@@ -813,7 +819,7 @@ sra_walk_modify_expr (tree expr, block_stmt_iterator *bsi,
if (!rhs_elt->is_scalar)
fns->ldst (rhs_elt, lhs, bsi, false);
else
- fns->use (rhs_elt, &TREE_OPERAND (expr, 1), bsi, false);
+ fns->use (rhs_elt, &TREE_OPERAND (expr, 1), bsi, false, false);
}
/* If it isn't scalarizable, there may be scalarizable variables within, so
@@ -859,7 +865,7 @@ sra_walk_modify_expr (tree expr, block_stmt_iterator *bsi,
/* Otherwise we're being used in some context that requires the
aggregate to be seen as a whole. Invoke USE. */
else
- fns->use (lhs_elt, &TREE_OPERAND (expr, 0), bsi, true);
+ fns->use (lhs_elt, &TREE_OPERAND (expr, 0), bsi, true, false);
}
/* Similarly to above, LHS_ELT being null only means that the LHS as a
@@ -967,7 +973,7 @@ find_candidates_for_sra (void)
static void
scan_use (struct sra_elt *elt, tree *expr_p ATTRIBUTE_UNUSED,
block_stmt_iterator *bsi ATTRIBUTE_UNUSED,
- bool is_output ATTRIBUTE_UNUSED)
+ bool is_output ATTRIBUTE_UNUSED, bool use_all ATTRIBUTE_UNUSED)
{
elt->n_uses += 1;
}
@@ -1472,6 +1478,23 @@ mark_all_v_defs (tree list)
}
}
+/* Mark every replacement under ELT with TREE_NO_WARNING. */
+
+static void
+mark_no_warning (struct sra_elt *elt)
+{
+ if (!elt->all_no_warning)
+ {
+ if (elt->replacement)
+ TREE_NO_WARNING (elt->replacement) = 1;
+ else
+ {
+ struct sra_elt *c;
+ for (c = elt->children; c ; c = c->sibling)
+ mark_no_warning (c);
+ }
+ }
+}
/* Build a single level component reference to ELT rooted at BASE. */
@@ -1815,7 +1838,7 @@ sra_replace (block_stmt_iterator *bsi, tree list)
static void
scalarize_use (struct sra_elt *elt, tree *expr_p, block_stmt_iterator *bsi,
- bool is_output)
+ bool is_output, bool use_all)
{
tree list = NULL, stmt = bsi_stmt (*bsi);
@@ -1850,7 +1873,11 @@ scalarize_use (struct sra_elt *elt, tree *expr_p, block_stmt_iterator *bsi,
if (is_output)
sra_insert_after (bsi, list);
else
- sra_insert_before (bsi, list);
+ {
+ sra_insert_before (bsi, list);
+ if (use_all)
+ mark_no_warning (elt);
+ }
}
}
@@ -2015,7 +2042,7 @@ scalarize_ldst (struct sra_elt *elt, tree other,
{
/* Since ELT is not fully instantiated, we have to leave the
block copy in place. Treat this as a USE. */
- scalarize_use (elt, NULL, bsi, is_output);
+ scalarize_use (elt, NULL, bsi, is_output, false);
}
else
{
--
GitLab