Fixed bug #72213 (Finally leaks on nested exceptions).

Squashed commit of the following:

commit 8461b0407fc9eab0869d43b84e6a92ba2fe06997
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed May 25 00:34:42 2016 +0300

    Rmoved zend_try_catch_element.parent and walk through op_array.try_catch_array backward from the current try_cacth_offset.

commit 0c71e249649bed178bfbef30bb3e63c57f07af05
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed May 25 00:04:53 2016 +0300

    Move SAVE_OPLINE() to its original place

commit 111432a4df738fcd65878a42f23194dc3c4983a2
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Wed May 25 00:01:10 2016 +0300

    Separate the common part of ZEND_HANDLE_EXCEPTION and FAST_RET into zend_dispatch_try_catch_finally_helper.

commit 4f21c06c2ec17819a708bc037f318784554a6ecd
Author: Nikita Popov <nikic@php.net>
Date:   Tue May 24 14:55:27 2016 +0200

    Improve finally fix

commit da5c7274997b8308e682b5bf280124e3a1483086
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue May 24 10:36:08 2016 +0300

    Fixed Zend/tests/try/bug70228_3.phpt and Zend/tests/try/bug70228_4.phpt

commit cfcedf2fb4f4fc1f7de9f7d53a3037fed7795f19
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue May 24 02:59:27 2016 +0300

    Added test

commit 4c6aa93d43da941eb4fda15b48154bfb104bdc04
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Tue May 24 00:38:20 2016 +0300

    Added tests

commit 8a8f4704b0eca2e460d42c1f253a363b0db8e510
Author: Dmitry Stogov <dmitry@zend.com>
Date:   Mon May 23 23:27:34 2016 +0300

    Fixed bug #72213 (Finally leaks on nested exceptions)

1 files changed, 23 insertions, 6 deletions

diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index 0994681c20..c6da34732a 100644
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -234,6 +234,7 @@ void zend_oparray_context_begin(zend_oparray_context *prev_context) /* {{{ */
 	CG(context).backpatch_count = 0;
 	CG(context).in_finally = 0;
 	CG(context).fast_call_var = -1;
+	CG(context).try_catch_offset = -1;
 	CG(context).current_brk_cont = -1;
 	CG(context).last_brk_cont = 0;
 	CG(context).brk_cont_array = NULL;
@@ -4008,6 +4009,12 @@ static int zend_handle_loops_and_finally_ex(zend_long depth) /* {{{ */
 			SET_UNUSED(opline->op1);
 			SET_UNUSED(opline->op2);
 			opline->op1.num = loop_var->u.try_catch_offset;
+		} else if (loop_var->opcode == ZEND_DISCARD_EXCEPTION) {
+			zend_op *opline = get_next_op(CG(active_op_array));
+			opline->opcode = ZEND_DISCARD_EXCEPTION;
+			opline->op1_type = IS_TMP_VAR;
+			opline->op1.var = loop_var->var_num;
+			SET_UNUSED(opline->op2);
 		} else if (loop_var->opcode == ZEND_RETURN) {
 			/* Stack separator */
 			break;
@@ -4057,12 +4064,6 @@ void zend_compile_return(zend_ast *ast) /* {{{ */
 		zend_compile_expr(&expr_node, expr_ast);
 	}
 
-	if (CG(context).in_finally) {
-		opline = zend_emit_op(NULL, ZEND_DISCARD_EXCEPTION, NULL, NULL);
-		opline->op1_type = IS_TMP_VAR;
-		opline->op1.var = CG(context).fast_call_var;
-	}
-
 	/* Generator return types are handled separately */
 	if (!(CG(active_op_array)->fn_flags & ZEND_ACC_GENERATOR) && CG(active_op_array)->fn_flags & ZEND_ACC_HAS_RETURN_TYPE) {
 		zend_emit_return_type_check(expr_ast ? &expr_node : NULL, CG(active_op_array)->arg_info - 1);
@@ -4573,6 +4574,7 @@ void zend_compile_try(zend_ast *ast) /* {{{ */
 	uint32_t try_catch_offset;
 	uint32_t *jmp_opnums = safe_emalloc(sizeof(uint32_t), catches->children, 0);
 	uint32_t orig_fast_call_var = CG(context).fast_call_var;
+	uint32_t orig_try_catch_offset = CG(context).try_catch_offset;
 
 	if (catches->children == 0 && !finally_ast) {
 		zend_error_noreturn(E_COMPILE_ERROR, "Cannot use try without catch or finally");
@@ -4606,6 +4608,8 @@ void zend_compile_try(zend_ast *ast) /* {{{ */
 		zend_stack_push(&CG(loop_var_stack), &fast_call);
 	}
 
+	CG(context).try_catch_offset = try_catch_offset;
+
 	zend_compile_stmt(try_ast);
 
 	if (catches->children != 0) {
@@ -4679,11 +4683,18 @@ void zend_compile_try(zend_ast *ast) /* {{{ */
 	}
 
 	if (finally_ast) {
+		zend_loop_var discard_exception;
 		uint32_t opnum_jmp = get_next_op_number(CG(active_op_array)) + 1;
 		
 		/* Pop FAST_CALL from unwind stack */
 		zend_stack_del_top(&CG(loop_var_stack));
 
+		/* Push DISCARD_EXCEPTION on unwind stack */
+		discard_exception.opcode = ZEND_DISCARD_EXCEPTION;
+		discard_exception.var_type = IS_TMP_VAR;
+		discard_exception.var_num = CG(context).fast_call_var;
+		zend_stack_push(&CG(loop_var_stack), &discard_exception);
+
 		CG(zend_lineno) = finally_ast->lineno;
 
 		opline = zend_emit_op(NULL, ZEND_FAST_CALL, NULL, NULL);
@@ -4704,12 +4715,18 @@ void zend_compile_try(zend_ast *ast) /* {{{ */
 		opline = zend_emit_op(NULL, ZEND_FAST_RET, NULL, NULL);
 		opline->op1_type = IS_TMP_VAR;
 		opline->op1.var = CG(context).fast_call_var;
+		opline->op2.num = orig_try_catch_offset;
 
 		zend_update_jump_target_to_next(opnum_jmp);
 
 		CG(context).fast_call_var = orig_fast_call_var;
+
+		/* Pop DISCARD_EXCEPTION from unwind stack */
+		zend_stack_del_top(&CG(loop_var_stack));
 	}
 
+	CG(context).try_catch_offset = orig_try_catch_offset;
+
 	efree(jmp_opnums);
 }
 /* }}} */