From 37612936a1ede4e656514dc62c42a5e42e976046 Mon Sep 17 00:00:00 2001 From: Nikita Popov Date: Tue, 1 Sep 2020 12:22:56 +0200 Subject: [PATCH] Fix pi node removal when removing predecessor We can't just remove the uses, we need to replace uses. The test case only fails on master with SSA integrity violations, but I believe the root issue also existed previously. --- Zend/tests/remove_predecessor_of_pi_node.phpt | 14 ++++++++++++++ ext/opcache/Optimizer/zend_ssa.c | 2 +- 2 files changed, 15 insertions(+), 1 deletion(-) create mode 100644 Zend/tests/remove_predecessor_of_pi_node.phpt diff --git a/Zend/tests/remove_predecessor_of_pi_node.phpt b/Zend/tests/remove_predecessor_of_pi_node.phpt new file mode 100644 index 0000000000..2346d5aa52 --- /dev/null +++ b/Zend/tests/remove_predecessor_of_pi_node.phpt @@ -0,0 +1,14 @@ +--TEST-- +Regression test for incorrect update of pi node users when removing a predecessor block +--FILE-- + +--EXPECTF-- +Notice: Undefined variable: n in %s on line %d diff --git a/ext/opcache/Optimizer/zend_ssa.c b/ext/opcache/Optimizer/zend_ssa.c index fdc383128b..89dfe57914 100644 --- a/ext/opcache/Optimizer/zend_ssa.c +++ b/ext/opcache/Optimizer/zend_ssa.c @@ -1388,7 +1388,7 @@ void zend_ssa_remove_predecessor(zend_ssa *ssa, int from, int to) /* {{{ */ for (phi = next_ssa_block->phis; phi; phi = phi->next) { if (phi->pi >= 0) { if (phi->pi == from) { - zend_ssa_remove_uses_of_var(ssa, phi->ssa_var); + zend_ssa_rename_var_uses(ssa, phi->ssa_var, phi->sources[0], /* update_types */ 0); zend_ssa_remove_phi(ssa, phi); } } else { -- 2.40.0