Fixed incorrect live-range construction

diff --git a/ext/opcache/jit/zend_jit.c b/ext/opcache/jit/zend_jit.c
index 0ad3d3883eea7641b8d78947f8b178fa8d62cc16..3dad8e4f911151386936729d2fc1f332ec04bb24 100644 (file)
--- a/ext/opcache/jit/zend_jit.c
+++ b/ext/opcache/jit/zend_jit.c
@@ -120,8 +120,17 @@ static uint32_t zend_jit_trace_get_exit_point(const zend_op *to_opline, uint32_t
 static const void *zend_jit_trace_get_exit_addr(uint32_t n);
 static void zend_jit_trace_add_code(const void *start, uint32_t size);
 
+static zend_bool dominates(const zend_basic_block *blocks, int a, int b) {
+       while (blocks[b].level > blocks[a].level) {
+               b = blocks[b].idom;
+       }
+       return a == b;
+}
+
 static zend_bool zend_ssa_is_last_use(const zend_op_array *op_array, const zend_ssa *ssa, int var, int use)
 {
+       int next_use;
+
        if (ssa->vars[var].phi_use_chain) {
                zend_ssa_phi *phi = ssa->vars[var].phi_use_chain;
                do {
@@ -132,8 +141,24 @@ static zend_bool zend_ssa_is_last_use(const zend_op_array *op_array, const zend_
                } while (phi);
        }
 
-       use = zend_ssa_next_use(ssa->ops, var, use);
-       return use < 0 || zend_ssa_is_no_val_use(op_array->opcodes + use, ssa->ops + use, var);
+       next_use = zend_ssa_next_use(ssa->ops, var, use);
+       if (next_use < 0) {
+               int b = ssa->cfg.map[use];
+               int prev_use = ssa->vars[var].use_chain;
+
+               while (prev_use >= 0 && prev_use != use) {
+                       if (b != ssa->cfg.map[prev_use]
+                        && dominates(ssa->cfg.blocks, b, ssa->cfg.map[prev_use])
+                        && !zend_ssa_is_no_val_use(op_array->opcodes + prev_use, ssa->ops + prev_use, var)) {
+                               return 0;
+                       }
+                       prev_use = zend_ssa_next_use(ssa->ops, var, prev_use);
+               }
+               return 1;
+       } else if (zend_ssa_is_no_val_use(op_array->opcodes + next_use, ssa->ops + next_use, var)) {
+               return 1;
+       }
+       return 0;
 }
 
 static zend_bool zend_ival_is_last_use(const zend_lifetime_interval *ival, int use)