No more global space for structure returns

diff --git a/lang/cem/cemcom.ansi/code.c b/lang/cem/cemcom.ansi/code.c
index 09b12f8..ed321be 100644 (file)
--- a/lang/cem/cemcom.ansi/code.c
+++ b/lang/cem/cemcom.ansi/code.c
@@ -46,6 +46,7 @@
 
 label lab_count = 1;
 label datlab_count = 1;
+arith fbytes;
 
 int fp_used;
 extern arith NewLocal();       /* util.c       */
@@ -212,7 +213,7 @@ code_scope(text, def)
 static label return_label, return2_label;
 static char return_expr_occurred;
 static arith func_size;
-static label func_res_label;
+static int struct_return;
 static char *last_fn_given = (char *)0;
 static label file_name_label;
 
@@ -281,12 +282,11 @@ begin_proc(ds, idf)               /* to be called when entering a procedure */
                if (func_size <= 0) {
                        error("unknown return type for function %s", name);
                } else {
-                       C_df_dlb(func_res_label = data_label());
-                       C_bss_cst(func_size, (arith)0, 1);
+                       struct_return = 1;
                }
        }
        else
-               func_res_label = 0;
+               struct_return = 0;
        /*      Special arrangements if the function result doesn't fit in
                the function return area of the EM machine.  The size of
                the function return area is implementation dependent.
@@ -318,8 +318,7 @@ begin_proc(ds, idf)         /* to be called when entering a procedure */
 #endif
 }
 
-end_proc(fbytes)
-       arith fbytes;
+end_proc()
 {
        /*      end_proc() deals with the code to be generated at the end of
                a function, as there is:
@@ -341,14 +340,14 @@ end_proc(fbytes)
                DfaEndFunction();
 #endif /* DATAFLOW */
        C_df_ilb(return2_label);
-       if (return_expr_occurred && func_res_label == 0) {
+       if (return_expr_occurred && struct_return == 0) {
                        C_asp(-func_size);
        }
        C_df_ilb(return_label);
        prc_exit();
        if (return_expr_occurred) {
-               if (func_res_label != 0)        {
-                       C_lae_dlb(func_res_label, (arith)0);
+               if (struct_return != 0) {
+                       LoadLocal(fbytes, pointer_size);
                        C_ret(pointer_size);
                }
                else
@@ -357,8 +356,8 @@ end_proc(fbytes)
        else    C_ret((arith) 0);
 
        /* getting the number of "local" bytes is posponed until here,
-          because copying the function result in "func_res_label" may
-          need temporaries! However, local_level is now L_FORMAL2, because
+          because copying the function result may need temporaries!
+          However, local_level is now L_FORMAL2, because
           L_LOCAL is already unstacked. Therefore, "unstack_level" must
           also pass "sl_max_block" to the level above L_LOCAL.
        */
@@ -367,6 +366,7 @@ end_proc(fbytes)
        C_beginpart(pro_id);
        C_pro(func_name, nbytes);
 #endif
+       if (struct_return) fbytes += pointer_size;
        if (fbytes > max_int) {
                error("%s has more than %ld parameter bytes",
                        func_name, (long) max_int);
@@ -410,8 +410,8 @@ do_return_expr(expr)
        */
        ch3cast(&expr, RETURN, func_type);
        code_expr(expr, RVAL, TRUE, NO_LABEL, NO_LABEL);
-       if (func_res_label != 0) {
-               C_lae_dlb(func_res_label, (arith)0);
+       if (struct_return != 0) {
+               LoadLocal(fbytes, pointer_size);
                store_block(func_size, func_type->tp_align);
        }
        C_bra(return_label);

diff --git a/lang/cem/cemcom.ansi/eval.c b/lang/cem/cemcom.ansi/eval.c
index ccc6ed1..be4250a 100644 (file)
--- a/lang/cem/cemcom.ansi/eval.c
+++ b/lang/cem/cemcom.ansi/eval.c
@@ -475,6 +475,7 @@ EVAL(expr, val, code, true_label, false_label)
                        register struct expr *ex;
                        arith ParSize = (arith)0;
                        label setjmp_label = 0;
+                       arith retspace = 0;
 
                        if (ISNAME(left)) {
                                if (left->VL_IDF->id_special == SP_SETJMP) {
@@ -488,6 +489,12 @@ EVAL(expr, val, code, true_label, false_label)
                                        ParSize += pointer_size;
                                }
                        }
+                       if (is_struct_or_union(tp->tp_fund)) {
+                               retspace = NewLocal(tp->tp_size, tp->tp_align,
+                                                   -1, 0);
+                               C_lal(retspace);
+                               ParSize += pointer_size;
+                       }
                        if ((ex = right) != NILEXPR) {
                                /* function call with parameters*/
                                while ( ex->ex_class == Oper &&
@@ -525,8 +532,10 @@ EVAL(expr, val, code, true_label, false_label)
                        if (gencode) {
                                if (is_struct_or_union(tp->tp_fund)) {
                                        C_lfr(pointer_size);
-                                       if (val == RVAL)
+                                       if (val == RVAL) {
                                          load_block(tp->tp_size, (int) word_size);
+                                         FreeLocal(retspace);
+                                       }
                                }
                                else
                                        C_lfr(ATW(tp->tp_size));
@@ -551,7 +560,7 @@ EVAL(expr, val, code, true_label, false_label)
                        break;
                case ',':
                        EVAL(left, RVAL, FALSE, NO_LABEL, NO_LABEL);
-                       EVAL(right, RVAL, gencode, true_label, false_label);
+                       EVAL(right, val, gencode, true_label, false_label);
                        break;
                case '~':
                        EVAL(right, RVAL, gencode, NO_LABEL, NO_LABEL);

diff --git a/lang/cem/cemcom.ansi/program.g b/lang/cem/cemcom.ansi/program.g
index 1c1a804..36f2061 100644 (file)
--- a/lang/cem/cemcom.ansi/program.g
+++ b/lang/cem/cemcom.ansi/program.g
@@ -67,6 +67,7 @@
 extern arith ifval;
 #endif /* NOPP */
 
+extern arith fbytes;
 extern error();
 }
 
@@ -197,7 +198,6 @@ non_function(register struct decspecs *ds; register struct declarator *dc;)
 /* 3.7.1 */
 function(struct decspecs *ds; struct declarator *dc;)
        {
-               arith fbytes;
                register struct idf *idf = dc->dc_idf;
        }
 :
@@ -222,7 +222,7 @@ function(struct decspecs *ds; struct declarator *dc;)
        }
        compound_statement
        {
-               end_proc(fbytes);
+               end_proc();
 #ifdef LINT
                lint_implicit_return();
 #endif /* LINT */