Hi.
And there's one more patch that deals with delete operator
which has a second argument (size). That definition GIMPLE
statement of the size must be also properly marked.
Patch can bootstrap on x86_64-linux-gnu and survives regression tests.
Ready to be installed?
Thanks,
Martin
>From 3d69c779ad5de447cd5ddba2595d2b1586dc5d3c Mon Sep 17 00:00:00 2001
From: Martin Liska <mli...@suse.cz>
Date: Sun, 28 Jul 2019 13:04:28 +0200
Subject: [PATCH] Remove also 2nd argument for unused delete operator (PR
tree-optimization/91270).
gcc/ChangeLog:
2019-07-28 Martin Liska <mli...@suse.cz>
PR tree-optimization/91270
* tree-ssa-dce.c (eliminate_unnecessary_stmts): Delete also 2nd
argument of a delete operator.
gcc/testsuite/ChangeLog:
2019-07-28 Martin Liska <mli...@suse.cz>
PR tree-optimization/91270
* g++.dg/torture/pr91270.C: New test.
---
gcc/testsuite/g++.dg/torture/pr91270.C | 10 ++++++++++
gcc/tree-ssa-dce.c | 14 ++++++++++++++
2 files changed, 24 insertions(+)
create mode 100644 gcc/testsuite/g++.dg/torture/pr91270.C
diff --git a/gcc/testsuite/g++.dg/torture/pr91270.C b/gcc/testsuite/g++.dg/torture/pr91270.C
new file mode 100644
index 00000000000..60d766e9e9f
--- /dev/null
+++ b/gcc/testsuite/g++.dg/torture/pr91270.C
@@ -0,0 +1,10 @@
+/* { dg-do compile } */
+
+struct S {
+ ~S();
+};
+int a = 123;
+void fn1() {
+ S *s = new S[a];
+ delete[] s;
+}
diff --git a/gcc/tree-ssa-dce.c b/gcc/tree-ssa-dce.c
index cf507fa0453..e5a1a9b7aa3 100644
--- a/gcc/tree-ssa-dce.c
+++ b/gcc/tree-ssa-dce.c
@@ -1294,6 +1294,20 @@ eliminate_unnecessary_stmts (void)
&& !gimple_plf (def_stmt, STMT_NECESSARY))
gimple_set_plf (stmt, STMT_NECESSARY, false);
}
+
+ /* Some delete operators have 2 arguments, where
+ the second argument is size of the deallocated memory. */
+ if (gimple_call_num_args (stmt) == 2)
+ {
+ tree ptr = gimple_call_arg (stmt, 1);
+ if (TREE_CODE (ptr) == SSA_NAME)
+ {
+ gimple *def_stmt = SSA_NAME_DEF_STMT (ptr);
+ if (!gimple_nop_p (def_stmt)
+ && !gimple_plf (def_stmt, STMT_NECESSARY))
+ gimple_set_plf (stmt, STMT_NECESSARY, false);
+ }
+ }
}
/* If GSI is not necessary then remove it. */
--
2.22.0
