More accurate tracing JIT for RETURN with unknown return address

diff --git a/ext/opcache/jit/zend_jit_internal.h b/ext/opcache/jit/zend_jit_internal.h
index 082f10b9808601da855b829bded96da6f15cbbe1..d8062dc253271a1e0d3f80d80777c81fdb856ccb 100644 (file)
--- a/ext/opcache/jit/zend_jit_internal.h
+++ b/ext/opcache/jit/zend_jit_internal.h
@@ -271,7 +271,6 @@ typedef struct _zend_jit_trace_rec {
                };
                struct {
                        union {
-                               uint8_t   recursive; /* part of recursive return sequence for ZEND_JIT_TRACE_BACK */
                                int8_t    return_value_used; /* for ZEND_JIT_TRACE_ENTER */
                                uint8_t   fake; /* for ZEND_JIT_TRACE_INIT_CALL */
                        };
@@ -382,18 +381,17 @@ struct _zend_jit_trace_stack_frame {
 #define TRACE_FRAME_MASK_RETURN_VALUE_USED   0x00000008
 #define TRACE_FRAME_MASK_RETURN_VALUE_UNUSED 0x00000010
 #define TRACE_FRAME_MASK_THIS_CHECKED        0x00000020
+#define TRACE_FRAME_MASK_UNKNOWN_RETURN      0x00000040
 
 
-#define TRACE_FRAME_INIT(frame, _func, nested, num_args) do { \
+#define TRACE_FRAME_INIT(frame, _func, _flags, num_args) do { \
                zend_jit_trace_stack_frame *_frame = (frame); \
                _frame->call = NULL; \
                _frame->prev = NULL; \
                _frame->func = (const zend_function*)_func; \
                _frame->call_level = 0; \
                _frame->_info = (((uint32_t)(num_args)) << TRACE_FRAME_SHIFT_NUM_ARGS) & TRACE_FRAME_MASK_NUM_ARGS; \
-               if (nested) { \
-                       _frame->_info |= TRACE_FRAME_MASK_NESTED; \
-               }; \
+               _frame->_info |= _flags; \
        } while (0)
 
 #define TRACE_FRAME_RETURN_SSA_VAR(frame) \
@@ -412,6 +410,8 @@ struct _zend_jit_trace_stack_frame {
        ((frame)->_info & TRACE_FRAME_MASK_RETURN_VALUE_UNUSED)
 #define TRACE_FRAME_IS_THIS_CHECKED(frame) \
        ((frame)->_info & TRACE_FRAME_MASK_THIS_CHECKED)
+#define TRACE_FRAME_IS_UNKNOWN_RETURN(frame) \
+       ((frame)->_info & TRACE_FRAME_MASK_UNKNOWN_RETURN)
 
 #define TRACE_FRAME_SET_RETURN_SSA_VAR(frame, var) do { \
                (frame)->_info = var; \

diff --git a/ext/opcache/jit/zend_jit_trace.c b/ext/opcache/jit/zend_jit_trace.c
index 270fe0cec0dc63ffe7613620e3409d8bb813d64c..46455f8d54465011aadda2f48f480f42c2acf2db 100644 (file)
--- a/ext/opcache/jit/zend_jit_trace.c
+++ b/ext/opcache/jit/zend_jit_trace.c
@@ -307,7 +307,7 @@ static int zend_jit_trace_may_exit(const zend_op_array *op_array, const zend_op
                case ZEND_RETURN_BY_REF:
                case ZEND_RETURN:
                        /* return */
-                       return trace->op == ZEND_JIT_TRACE_BACK && trace->recursive;
+                       return !JIT_G(current_frame) || TRACE_FRAME_IS_UNKNOWN_RETURN(JIT_G(current_frame));
                default:
                        break;
        }
@@ -2479,7 +2479,7 @@ static const void *zend_jit_trace(zend_jit_trace_rec *trace_buffer, uint32_t par
        op_array = p->op_array;
        frame = JIT_G(current_frame);
        top = zend_jit_trace_call_frame(frame, op_array);
-       TRACE_FRAME_INIT(frame, op_array, 0, -1);
+       TRACE_FRAME_INIT(frame, op_array, TRACE_FRAME_MASK_UNKNOWN_RETURN, -1);
        stack = frame->stack;
 
        opline = ((zend_jit_trace_start_rec*)p)->opline;
@@ -3872,7 +3872,7 @@ done:
                                ZEND_ASSERT(&frame->func->op_array == op_array);
                        } else {
                                frame = zend_jit_trace_ret_frame(frame, op_array);
-                               TRACE_FRAME_INIT(frame, op_array, 0, -1);
+                               TRACE_FRAME_INIT(frame, op_array, TRACE_FRAME_MASK_UNKNOWN_RETURN, -1);
                                stack = frame->stack;
                                for (i = 0; i < op_array->last_var + op_array->T; i++) {
                                        /* Initialize abstract stack using SSA */
@@ -3917,7 +3917,7 @@ done:
                        }
 
                        call = top;
-                       TRACE_FRAME_INIT(call, p->func, 1, num_args);
+                       TRACE_FRAME_INIT(call, p->func, TRACE_FRAME_MASK_NESTED, num_args);
                        call->prev = frame->call;
                        if (!p->fake) {
                                TRACE_FRAME_SET_LAST_SEND_BY_VAL(call);

diff --git a/ext/opcache/jit/zend_jit_vm_helpers.c b/ext/opcache/jit/zend_jit_vm_helpers.c
index 2cfb79dbb6411cb1f9d6691a714788eec7d7bdfe..c4a515330d8715e73f91ede34931e963fc1fd843 100644 (file)
--- a/ext/opcache/jit/zend_jit_vm_helpers.c
+++ b/ext/opcache/jit/zend_jit_vm_helpers.c
@@ -367,9 +367,8 @@ ZEND_OPCODE_HANDLER_RET ZEND_FASTCALL zend_jit_loop_trace_helper(ZEND_OPCODE_HAN
                break; \
        }
 
-#define TRACE_RECORD_BACK(_op, _recursive, _ptr) \
+#define TRACE_RECORD_BACK(_op, _ptr) \
        trace_buffer[idx].op = _op; \
-       trace_buffer[idx].recursive = _recursive; \
        trace_buffer[idx].ptr = _ptr; \
        idx++; \
        if (idx >= ZEND_JIT_TRACE_MAX_LENGTH - 1) { \
@@ -545,7 +544,7 @@ zend_jit_trace_stop ZEND_FASTCALL zend_jit_trace_execute(zend_execute_data *ex,
        zend_execute_data *save_execute_data = execute_data;
        const zend_op *save_opline = opline;
 #endif
-       const zend_op *orig_opline;
+       const zend_op *orig_opline, *end_opline;
        zend_jit_trace_stop stop = ZEND_JIT_TRACE_STOP_ERROR;
        int level = 0;
        int ret_level = 0;
@@ -757,7 +756,7 @@ zend_jit_trace_stop ZEND_FASTCALL zend_jit_trace_execute(zend_execute_data *ex,
                                                        stop = ZEND_JIT_TRACE_STOP_TOO_DEEP_RET;
                                                        break;
                                                }
-                                               TRACE_RECORD_BACK(ZEND_JIT_TRACE_BACK, 1, &EX(func)->op_array);
+                                               TRACE_RECORD_BACK(ZEND_JIT_TRACE_BACK, &EX(func)->op_array);
                                                count = zend_jit_trace_recursive_ret_count(&EX(func)->op_array, unrolled_calls, ret_level);
                                                if (opline == orig_opline) {
                                                        if (count + 1 >= ZEND_JIT_TRACE_MAX_RECURSION) {
@@ -791,7 +790,7 @@ zend_jit_trace_stop ZEND_FASTCALL zend_jit_trace_execute(zend_execute_data *ex,
                                        }
                                } else {
                                        level--;
-                                       TRACE_RECORD_BACK(ZEND_JIT_TRACE_BACK, 0, &EX(func)->op_array);
+                                       TRACE_RECORD_BACK(ZEND_JIT_TRACE_BACK, &EX(func)->op_array);
                                }
                        }
 #ifdef HAVE_GCC_GLOBAL_REGS
@@ -877,14 +876,17 @@ zend_jit_trace_stop ZEND_FASTCALL zend_jit_trace_execute(zend_execute_data *ex,
                }
        }
 
+       end_opline = opline;
        if (!ZEND_JIT_TRACE_STOP_OK(stop)) {
                if (backtrack_recursion > 0) {
                        idx = backtrack_recursion;
                        stop = ZEND_JIT_TRACE_STOP_RECURSIVE_CALL;
+                       end_opline = orig_opline;
                } else if (backtrack_ret_recursion > 0) {
                        idx = backtrack_ret_recursion;
                        ret_level = backtrack_ret_recursion_level;
                        stop = ZEND_JIT_TRACE_STOP_RECURSIVE_RET;
+                       end_opline = orig_opline;
                }
        }
 
@@ -895,7 +897,7 @@ zend_jit_trace_stop ZEND_FASTCALL zend_jit_trace_execute(zend_execute_data *ex,
                }
        }
 
-       TRACE_END(ZEND_JIT_TRACE_END, stop, opline);
+       TRACE_END(ZEND_JIT_TRACE_END, stop, end_opline);
 
 #ifdef HAVE_GCC_GLOBAL_REGS
        if (stop != ZEND_JIT_TRACE_STOP_HALT) {

diff --git a/ext/opcache/jit/zend_jit_x86.dasc b/ext/opcache/jit/zend_jit_x86.dasc
index 7f2bb4b394caef06c407ec8a44873d8d6c009012..642fb702111825969e044f2eb0d4ebb8355e6fec 100644 (file)
--- a/ext/opcache/jit/zend_jit_x86.dasc
+++ b/ext/opcache/jit/zend_jit_x86.dasc
@@ -9477,7 +9477,7 @@ static int zend_jit_leave_func(dasm_State **Dst, const zend_op *opline, const ze
        |9:
        if (trace) {
                if (trace->op != ZEND_JIT_TRACE_END
-                && (trace->op != ZEND_JIT_TRACE_BACK || !trace->recursive)) {
+                && (JIT_G(current_frame) && !TRACE_FRAME_IS_UNKNOWN_RETURN(JIT_G(current_frame)))) {
                        zend_jit_reset_opline(Dst, NULL);
                } else {
                        // TODO: exception handling for tracing JIT ???
@@ -9487,9 +9487,8 @@ static int zend_jit_leave_func(dasm_State **Dst, const zend_op *opline, const ze
 
                |8:
 
-               if (opline->opcode == ZEND_RETURN
-                && trace->op == ZEND_JIT_TRACE_BACK
-                && trace->recursive) {
+               if (trace->op == ZEND_JIT_TRACE_BACK
+                && (!JIT_G(current_frame) || TRACE_FRAME_IS_UNKNOWN_RETURN(JIT_G(current_frame)))) {
                        const zend_op *next_opline = trace->opline;
                        uint32_t exit_point;
                        const void *exit_addr;