Handle initialized darray of strings

This includes adding support for returning strings from functions,
adding initializing new darray with array_pattern strings, and
assigning an array_pattern of strings to a preallocated darray.
Also fix up support for initializing array with simple string
expression.

PExpr.h

@@ -632,6 +632,9 @@ class PEString : public PExpr {
       virtual unsigned test_width(Design*des, NetScope*scope,
 				  width_mode_t&mode);
 
+      virtual NetEConst*elaborate_expr(Design*des, NetScope*scope,
+				       ivl_type_t type, unsigned flags) const;
+
       virtual NetEConst*elaborate_expr(Design*des, NetScope*,
 				       unsigned expr_wid, unsigned) const;
       verinum* eval_const(Design*, NetScope*) const;

elab_expr.cc

@@ -4898,6 +4898,16 @@ unsigned PEString::test_width(Design*, NetScope*, width_mode_t&)
       return expr_width_;
 }
 
+NetEConst* PEString::elaborate_expr(Design*, NetScope*, ivl_type_t type, unsigned)const
+{
+      verinum val(value());
+      NetEConst*tmp = new NetEConst(val);
+      tmp->cast_signed(signed_flag_);
+      tmp->set_line(*this);
+
+      return tmp;
+}
+
 NetEConst* PEString::elaborate_expr(Design*, NetScope*,
 				    unsigned expr_wid, unsigned) const
 {

tgt-vvp/draw_ufunc.c

@@ -214,7 +214,23 @@ void draw_ufunc_real(ivl_expr_t expr)
       fprintf(vvp_out, "  %%load/real v%p_0;\n", retval);
 
       draw_ufunc_epilogue(expr);
+}
 
+void draw_ufunc_string(ivl_expr_t expr)
+{
+      ivl_scope_t def = ivl_expr_def(expr);
+      ivl_signal_t retval = ivl_scope_port(def, 0);
+
+	/* Take in arguments to function and call the function code. */
+      draw_ufunc_preamble(expr);
+
+	/* Return value signal cannot be an array. */
+      assert(ivl_signal_dimensions(retval) == 0);
+
+	/* Load the result into a word. */
+      fprintf(vvp_out, "  %%load/str v%p_0;\n", retval);
+
+      draw_ufunc_epilogue(expr);
 }
 
 void draw_ufunc_object(ivl_expr_t expr)

tgt-vvp/eval_object.c

@@ -90,6 +90,14 @@ static int eval_darray_new(ivl_expr_t ex)
 			fprintf(vvp_out, "    %%pop/real 1;\n");
 		  }
 		  break;
+		case IVL_VT_STRING:
+		  for (idx = 0 ; idx < ivl_expr_parms(init_expr) ; idx += 1) {
+			draw_eval_string(ivl_expr_parm(init_expr,idx));
+			fprintf(vvp_out, "    %%ix/load 3, %u, 0;\n", idx);
+			fprintf(vvp_out, "    %%set/dar/obj/str 3;\n");
+			fprintf(vvp_out, "    %%pop/str 1;\n");
+		  }
+		  break;
 		default:
 		  fprintf(vvp_out, "; ERROR: Sorry, this type not supported here.\n");
 		  errors += 1;
@@ -123,6 +131,14 @@ static int eval_darray_new(ivl_expr_t ex)
 		  }
 		  fprintf(vvp_out, "    %%pop/real 1;\n");
 		  break;
+		case IVL_VT_STRING:
+		  draw_eval_string(init_expr);
+		  for (idx = 0 ; idx < cnt ; idx += 1) {
+			fprintf(vvp_out, "    %%ix/load 3, %ld, 0;\n", idx);
+			fprintf(vvp_out, "    %%set/dar/obj/str 3;\n");
+		  }
+		  fprintf(vvp_out, "    %%pop/str 1;\n");
+		  break;
 		default:
 		  fprintf(vvp_out, "; ERROR: Sorry, this type not supported here.\n");
 		  errors += 1;

tgt-vvp/eval_string.c

@@ -180,6 +180,10 @@ void draw_eval_string(ivl_expr_t expr)
 		  fallback_eval(expr);
 	    break;
 
+	  case IVL_EX_UFUNC:
+	    draw_ufunc_string(expr);
+	    break;
+
 	  default:
 	    fallback_eval(expr);
 	    break;

tgt-vvp/stmt_assign.c

@@ -853,6 +853,13 @@ static int show_stmt_assign_darray_pattern(ivl_statement_t net)
 		  fprintf(vvp_out, "    %%ix/load 3, %u, 0;\n", idx);
 		  fprintf(vvp_out, "    %%store/dar/r v%p_0;\n", var);
 		  break;
+
+		case IVL_VT_STRING:
+		  draw_eval_string(ivl_expr_parm(rval,idx));
+		  fprintf(vvp_out, "    %%ix/load 3, %u, 0;\n", idx);
+		  fprintf(vvp_out, "    %%store/dar/str v%p_0;\n", var);
+		  break;
+
 		default:
 		  fprintf(vvp_out, "; ERROR: show_stmt_assign_darray_pattern: type_base=%d not implemented\n", ivl_type_base(element_type));
 		  errors += 1;

tgt-vvp/vvp_priv.h

@@ -106,6 +106,7 @@ extern void draw_lpm_mux(ivl_lpm_t net);
 
 extern struct vector_info draw_ufunc_expr(ivl_expr_t expr, unsigned wid);
 extern void draw_ufunc_real(ivl_expr_t expr);
+extern void draw_ufunc_string(ivl_expr_t expr);
 extern void draw_ufunc_object(ivl_expr_t expr);
 
 extern void pad_expr_in_place(ivl_expr_t expr, struct vector_info res,

vvp/codes.h

@@ -183,6 +183,7 @@ extern bool of_SET_AV(vthread_t thr, vvp_code_t code);
 extern bool of_SET_DAR(vthread_t thr, vvp_code_t code);
 extern bool of_SET_DAR_OBJ(vthread_t thr, vvp_code_t code);
 extern bool of_SET_DAR_OBJ_REAL(vthread_t thr, vvp_code_t code);
+extern bool of_SET_DAR_OBJ_STR(vthread_t thr, vvp_code_t code);
 extern bool of_SET_VEC(vthread_t thr, vvp_code_t code);
 extern bool of_SET_X0(vthread_t thr, vvp_code_t code);
 extern bool of_SET_X0_X(vthread_t thr, vvp_code_t code);

vvp/compile.cc

@@ -231,6 +231,7 @@ static const struct opcode_table_s opcode_table[] = {
       { "%set/dar",of_SET_DAR,3,  {OA_FUNC_PTR, OA_BIT1,     OA_BIT2} },
       { "%set/dar/obj",     of_SET_DAR_OBJ,     3,{OA_NUMBER,OA_BIT1,OA_BIT2} },
       { "%set/dar/obj/real",of_SET_DAR_OBJ_REAL,1,{OA_NUMBER,OA_NONE,OA_NONE} },
+      { "%set/dar/obj/str", of_SET_DAR_OBJ_STR, 1,{OA_NUMBER,OA_NONE,OA_NONE} },
       { "%set/v",  of_SET_VEC,3,  {OA_FUNC_PTR, OA_BIT1,     OA_BIT2} },
       { "%set/x0", of_SET_X0, 3,  {OA_FUNC_PTR, OA_BIT1,     OA_BIT2} },
       { "%shiftl/i0", of_SHIFTL_I0, 2, {OA_BIT1,OA_NUMBER,   OA_NONE} },

vvp/opcodes.txt

@@ -963,10 +963,15 @@ a dynamic array that is in the top of the object stack. Instead of
 using a fixed index register, use the register addressed by <index>.
 
 * %set/dar/obj/real <index>
+* %set/dar/obj/str <index>
 
 The "%set/dar/obj/real" opcode sets the top value from the real-value
 stack to the index. This does NOT pop the real value off the
-stack. The intent is that this value may be written to a bunch of values.
+stack. The intent is that this value may be written to a bunch of
+values.
+
+The "%set/dar/obj/str" opcode does the same but for string values and
+uses the string stack.
 
 * %set/v <var-label>, <bit>, <wid>
 

vvp/vthread.cc

@@ -4957,6 +4957,23 @@ bool of_SET_DAR_OBJ_REAL(vthread_t thr, vvp_code_t cp)
       return true;
 }
 
+/*
+ * %set/dar/obj/str <index>
+ */
+bool of_SET_DAR_OBJ_STR(vthread_t thr, vvp_code_t cp)
+{
+      unsigned adr = thr->words[cp->number].w_int;
+
+      string value = thr->peek_str(0);
+
+      vvp_object_t&top = thr->peek_object();
+      vvp_darray*darray = top.peek<vvp_darray>();
+      assert(darray);
+
+      darray->set_word(adr, value);
+      return true;
+}
+
 /*
  * This implements the "%set/v <label>, <bit>, <wid>" instruction.
  *