From 8f6dd185d16dec8ca9351a754f0ece153f89d85c Mon Sep 17 00:00:00 2001
From: Jakub Jelinek <jakub@redhat.com>
Date: Thu, 23 Jan 2025 20:03:36 +0100
Subject: [PATCH] vect: Avoid copying of uninitialized variable [PR118628]
vectorizable_{store,load} does roughly
tree offvar;
tree running_off;
if (!costing_p)
{
... initialize offvar ...
}
running_off = offvar;
for (...)
{
if (costing_p)
{
...
continue;
}
... use running_off ...
}
so, it copies unconditionally sometimes uninitialized variable (but then
uses the copied variable only if it was set to something initialized).
Still, I think it is better to avoid copying around maybe uninitialized
vars.
2025-01-23 Jakub Jelinek <jakub@redhat.com>
PR tree-optimization/118628
* tree-vect-stmts.cc (vectorizable_store, vectorizable_load):
Initialize offvar to NULL_TREE.
---
gcc/tree-vect-stmts.cc | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)
diff --git a/gcc/tree-vect-stmts.cc b/gcc/tree-vect-stmts.cc
index c0550acf6b2b..1b639ae3b174 100644
--- a/gcc/tree-vect-stmts.cc
+++ b/gcc/tree-vect-stmts.cc
@@ -8645,7 +8645,7 @@ vectorizable_store (vec_info *vinfo,
gimple_stmt_iterator incr_gsi;
bool insert_after;
gimple *incr;
- tree offvar;
+ tree offvar = NULL_TREE;
tree ivstep;
tree running_off;
tree stride_base, stride_step, alias_off;
@@ -10603,7 +10603,7 @@ vectorizable_load (vec_info *vinfo,
{
gimple_stmt_iterator incr_gsi;
bool insert_after;
- tree offvar;
+ tree offvar = NULL_TREE;
tree ivstep;
tree running_off;
vec<constructor_elt, va_gc> *v = NULL;
--
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