This fixes the get_earlier_stmt call in vect_preserves_scalar_order_p to
properly use non-pattern stmts. I came along this when reworking
how we change DR_STMT during vectorization - this mimics the way
the SLP code uses get_later_stmt.
I've added asserts into get_earlier/later_stmt to make sure we're never
called on pattern stmts (those can end up with UIDs out-of-order).
Not sure if we actually run into this (not in the testsuite),
but it'll be a separate rev to bisect to and backport if required.
Bootstrap and regtest running on x86_64-unknown-linux-gnu.
Richard.
>From 823c9b42d8910c78413e087acf3bb5546b04b300 Mon Sep 17 00:00:00 2001
From: Richard Guenther <rguent...@suse.de>
Date: Tue, 29 May 2018 13:44:18 +0200
Subject: [PATCH] fix-dr-order-checks
* tree-vect-data-refs.c (vect_preserves_scalar_order_p): Make
sure to use non-pattern stmts for get_earlier_stmt arguments.
* tree-vectorizer.h (get_earlier_stmt): Assert we do not get
called on pattern stmts.
(get_later_stmt): Likewise.
diff --git a/gcc/tree-vect-data-refs.c b/gcc/tree-vect-data-refs.c
index f46eb467da6..9255c53189d 100644
--- a/gcc/tree-vect-data-refs.c
+++ b/gcc/tree-vect-data-refs.c
@@ -212,6 +212,10 @@ vect_preserves_scalar_order_p (gimple *stmt_a, gimple
*stmt_b)
(but could happen later) while reads will happen no later than their
current position (but could happen earlier). Reordering is therefore
only possible if the first access is a write. */
+ if (is_pattern_stmt_p (stmtinfo_a))
+ stmt_a = STMT_VINFO_RELATED_STMT (stmtinfo_a);
+ if (is_pattern_stmt_p (stmtinfo_b))
+ stmt_b = STMT_VINFO_RELATED_STMT (stmtinfo_b);
gimple *earlier_stmt = get_earlier_stmt (stmt_a, stmt_b);
return !DR_IS_WRITE (STMT_VINFO_DATA_REF (vinfo_for_stmt (earlier_stmt)));
}
diff --git a/gcc/tree-vectorizer.h b/gcc/tree-vectorizer.h
index f7646349b65..25d0aae8eaa 100644
--- a/gcc/tree-vectorizer.h
+++ b/gcc/tree-vectorizer.h
@@ -1068,8 +1068,12 @@ get_earlier_stmt (gimple *stmt1, gimple *stmt2)
if (uid1 == 0 || uid2 == 0)
return NULL;
- gcc_checking_assert (uid1 <= stmt_vec_info_vec->length ()
- && uid2 <= stmt_vec_info_vec->length ());
+ gcc_assert (uid1 <= stmt_vec_info_vec->length ()
+ && uid2 <= stmt_vec_info_vec->length ());
+ gcc_checking_assert ((STMT_VINFO_IN_PATTERN_P (vinfo_for_stmt (stmt1))
+ || !STMT_VINFO_RELATED_STMT (vinfo_for_stmt (stmt1)))
+ && (STMT_VINFO_IN_PATTERN_P (vinfo_for_stmt (stmt2))
+ || !STMT_VINFO_RELATED_STMT (vinfo_for_stmt
(stmt2))));
if (uid1 < uid2)
return stmt1;
@@ -1096,8 +1100,12 @@ get_later_stmt (gimple *stmt1, gimple *stmt2)
if (uid1 == 0 || uid2 == 0)
return NULL;
- gcc_assert (uid1 <= stmt_vec_info_vec->length ());
- gcc_assert (uid2 <= stmt_vec_info_vec->length ());
+ gcc_assert (uid1 <= stmt_vec_info_vec->length ()
+ && uid2 <= stmt_vec_info_vec->length ());
+ gcc_checking_assert ((STMT_VINFO_IN_PATTERN_P (vinfo_for_stmt (stmt1))
+ || !STMT_VINFO_RELATED_STMT (vinfo_for_stmt (stmt1)))
+ && (STMT_VINFO_IN_PATTERN_P (vinfo_for_stmt (stmt2))
+ || !STMT_VINFO_RELATED_STMT (vinfo_for_stmt
(stmt2))));
if (uid1 > uid2)
return stmt1;
