Merge pull request #456 from s-hadinger/berry_parser_022025

Fix parser bug in rare case

Author: skiars

src/be_code.c

@@ -698,15 +698,20 @@ static void setsfxvar(bfuncinfo *finfo, bopcode op, bexpdesc *e1, int src)
 int be_code_setvar(bfuncinfo *finfo, bexpdesc *e1, bexpdesc *e2, bbool keep_reg)
 {
     /* free_e2 indicates special case where ETINDEX or ETMEMBER need to be freed if top of registers */
-    bbool free_e2 = (e2->type == ETINDEX || e2->type == ETMEMBER) && (e2->v.ss.idx != e1->v.idx) && (e2->v.ss.idx == finfo->freereg - 1);
+    bbool free_e2 = (e2->type == ETINDEX || e2->type == ETMEMBER) &&
+                        (((e2->v.ss.idx != e1->v.idx) && (e2->v.ss.idx == finfo->freereg - 1)) ||
+                         ((e2->v.ss.obj != e1->v.idx) && (e2->v.ss.obj == finfo->freereg - 1)) );
     int src = exp2reg(finfo, e2,
         e1->type == ETLOCAL ? e1->v.idx : -1); /* Convert e2 to kreg */
         /* If e1 is a local variable, use the register */
 
     if (!keep_reg && (e1->type != ETLOCAL || e1->v.idx != src)) {
         free_expreg(finfo, e2); /* free source (checks only ETREG) */ /* TODO e2 is at top */
     } else if (!keep_reg && free_e2) {
-        be_code_freeregs(finfo, 1);
+        /* remove only if we know it's not a local variable */
+        if (finfo->freereg > (bbyte)be_list_count(finfo->local)) {
+            be_code_freeregs(finfo, 1);
+        }
     }
     switch (e1->type) {
     case ETLOCAL: /* It can't be ETREG. */

tests/parser.be

@@ -9,3 +9,17 @@ def f()
     end
 end
 assert(f() == 2)
+
+# Parser error reported in Feb 2025
+def parse_022025()
+    var s, value
+    var js = {'a':{'a':1}}
+    value = js['a']['a']
+
+    if value != nil
+        for x:0..1
+            return x
+        end
+    end
+end
+assert(parse_022025() == 0)