Optimize code generated for "while" and "for" loops.

Eliminate one JMP opcode for each loop iteration.

diff --git a/Zend/zend_compile.c b/Zend/zend_compile.c
index 1a7f4d0bc9ef818a0475ed7c0d1dbf878c03e43b..7b2ac281f34b3ea34b7a301af65999452223e059 100644 (file)
--- a/Zend/zend_compile.c
+++ b/Zend/zend_compile.c
@@ -3251,23 +3251,23 @@ void zend_compile_while(zend_ast *ast) /* {{{ */
 {
        zend_ast *cond_ast = ast->child[0];
        zend_ast *stmt_ast = ast->child[1];
-
        znode cond_node;
-       uint32_t opnum_start, opnum_jmpz;
+       uint32_t opnum_start, opnum_jmp, opnum_cond;
 
-       opnum_start = get_next_op_number(CG(active_op_array));
-       zend_compile_expr(&cond_node, cond_ast);
+       opnum_jmp = zend_emit_jump(0);
 
-       opnum_jmpz = zend_emit_cond_jump(ZEND_JMPZ, &cond_node, 0);
        zend_begin_loop();
 
+       opnum_start = get_next_op_number(CG(active_op_array));
        zend_compile_stmt(stmt_ast);
 
-       zend_emit_jump(opnum_start);
+       opnum_cond = get_next_op_number(CG(active_op_array));
+       zend_update_jump_target(opnum_jmp, opnum_cond);
+       zend_compile_expr(&cond_node, cond_ast);
 
-       zend_update_jump_target_to_next(opnum_jmpz);
+       zend_emit_cond_jump(ZEND_JMPNZ, &cond_node, opnum_start);
 
-       zend_end_loop(opnum_start, 0);
+       zend_end_loop(opnum_cond, 0);
 }
 /* }}} */
 
@@ -3323,27 +3323,27 @@ void zend_compile_for(zend_ast *ast) /* {{{ */
        zend_ast *stmt_ast = ast->child[3];
 
        znode result;
-       uint32_t opnum_cond, opnum_jmpz, opnum_loop;
+       uint32_t opnum_start, opnum_cond, opnum_jmp, opnum_loop;
 
        zend_compile_expr_list(&result, init_ast);
        zend_do_free(&result);
 
-       opnum_cond = get_next_op_number(CG(active_op_array));
-       zend_compile_expr_list(&result, cond_ast);
-       zend_do_extended_info();
+       opnum_jmp = zend_emit_jump(0);
 
-       opnum_jmpz = zend_emit_cond_jump(ZEND_JMPZ, &result, 0);
        zend_begin_loop();
 
+       opnum_start = get_next_op_number(CG(active_op_array));
        zend_compile_stmt(stmt_ast);
 
        opnum_loop = get_next_op_number(CG(active_op_array));
        zend_compile_expr_list(&result, loop_ast);
        zend_do_free(&result);
 
-       zend_emit_jump(opnum_cond);
+       zend_update_jump_target_to_next(opnum_jmp);
+       zend_compile_expr_list(&result, cond_ast);
+       zend_do_extended_info();
 
-       zend_update_jump_target_to_next(opnum_jmpz);
+       zend_emit_cond_jump(ZEND_JMPNZ, &result, opnum_start);
 
        zend_end_loop(opnum_loop, 0);
 }