c: Fix compile time hog in c_genericize [PR107127]
The complex multiplications result in deeply nested set of many SAVE_EXPRs,
which takes even on fast machines over 5 minutes to walk.
This patch fixes that by using walk_tree_without_duplicates where it is
instant.
2022-11-23 Andrew Pinski <apinski@marvell.com>
Jakub Jelinek <jakub@redhat.com>
PR c/107127
* c-gimplify.cc (c_genericize): Use walk_tree_without_duplicates
instead of walk_tree for c_genericize_control_r.
* gcc.dg/pr107127.c: New test.
diff --git a/gcc/c-family/c-gimplify.cc b/gcc/c-family/c-gimplify.cc
index 039a4b9..0034d41 100644
--- a/gcc/c-family/c-gimplify.cc
+++ b/gcc/c-family/c-gimplify.cc
@@ -572,8 +572,8 @@
bc_state_t save_state;
push_cfun (DECL_STRUCT_FUNCTION (fndecl));
save_bc_state (&save_state);
- walk_tree (&DECL_SAVED_TREE (fndecl), c_genericize_control_r,
- NULL, NULL);
+ walk_tree_without_duplicates (&DECL_SAVED_TREE (fndecl),
+ c_genericize_control_r, NULL);
restore_bc_state (&save_state);
pop_cfun ();
}
diff --git a/gcc/testsuite/gcc.dg/pr107127.c b/gcc/testsuite/gcc.dg/pr107127.c
new file mode 100644
index 0000000..f7ae87d
--- /dev/null
+++ b/gcc/testsuite/gcc.dg/pr107127.c
@@ -0,0 +1,12 @@
+/* PR c/107127 */
+/* { dg-do compile } */
+/* { dg-options "" } */
+
+int *v;
+
+_Complex double
+foo (_Complex double a, double b, double c)
+{
+ return v[0] / ((((c * (0 - 0 / a + 699.0 + 7.05 - 286.0 - +-4.65 + 1.57 + 0) * 0.1 - 3.28 + 4.22 + 0.1)) * b + 5.06)
+ * 1.23 * 8.0 * 12.0 * 16.0 * 2.0 * 2.0 * 0.25 * 0.125 * 18.2 * -15.25 * 0.0001
+ * 42.0 * 0.012 - 8.45 + 0 + 88.0 + 6.96 + 867.0 + 9.10 - 7.04 * -1.0);
