Update driver snapshots after decay tests.

Fix IR test failure.
Regenerate ARM IR snapshots to reflect the corrected lowering.
Restore ARM/RISC-V codegen files to original structure after earlier brace experiment.
Treat zero-length array compound literals as constant zero during lowering so scalar uses don't load garbage.

Fix coding style for parser.c according to cubic's suggestion. Ignore comment modification in tests/driver.sh

Author: lorettayao

src/parser.c

@@ -1402,6 +1402,7 @@ var_t *scalarize_array_literal(block_t *parent,
     scalar->init_val = array_var->init_val;
 
     add_insn(parent, *bb, OP_read, scalar, array_var, NULL, elem_size, NULL);
+
     return scalar;
 }
 void read_inner_var_decl(var_t *vd, bool anon, bool is_param)
@@ -2154,6 +2155,12 @@ void read_expr_operand(block_t *parent, basic_block_t **bb)
                 add_insn(parent, *bb, OP_allocat, compound_var, NULL, NULL, 0,
                          NULL);
                 parse_array_compound_literal(compound_var, parent, bb, true);
+
+                if (compound_var->array_size == 0) {
+                    compound_var->init_val = 0;
+                    add_insn(parent, *bb, OP_load_constant, compound_var, NULL,
+                             NULL, 0, NULL);
+                }
                 opstack_push(compound_var);
                 consumed_close_brace = true;
             } else if (cast_ptr_level > 0) {
@@ -4529,9 +4536,7 @@ basic_block_t *read_body_statement(block_t *parent, basic_block_t *bb)
                     read_expr(parent, &bb);
                     read_ternary_operation(parent, &bb);
 
-                    var_t *expr_result = opstack_pop();
-
-                    var_t *rhs = expr_result;
+                    var_t *rhs = opstack_pop();
                     if (!var->ptr_level && var->array_size == 0)
                         rhs = scalarize_array_literal(parent, &bb, rhs,
                                                       var->type);
@@ -4628,8 +4633,7 @@ basic_block_t *read_body_statement(block_t *parent, basic_block_t *bb)
                     } else {
                         read_expr(parent, &bb);
                         read_ternary_operation(parent, &bb);
-                        var_t *expr_result = opstack_pop();
-                        var_t *rhs = expr_result;
+                        var_t *rhs = opstack_pop();
                         if (!nv->ptr_level && nv->array_size == 0)
                             rhs = scalarize_array_literal(parent, &bb, rhs,
                                                           nv->type);