Add raise_error pass

Raise errors from attributes for testing.
I want it for bugpoint tests but it could be useful elsewhere.

kernel/constids.inc

@@ -286,3 +286,4 @@ X(A_WIDTHS)
 X(B_WIDTHS)
 X(C_WIDTHS)
 X(C_SIGNED)
+X(raise_error)

passes/tests/Makefile.inc

@@ -2,4 +2,5 @@
 OBJS += passes/tests/test_autotb.o
 OBJS += passes/tests/test_cell.o
 OBJS += passes/tests/test_abcloop.o
+OBJS += passes/tests/raise_error.o
 

passes/tests/raise_error.cc

@@ -0,0 +1,61 @@
+#include "kernel/yosys.h"
+
+USING_YOSYS_NAMESPACE
+PRIVATE_NAMESPACE_BEGIN
+
+struct RaiseErrorPass : public Pass {
+	RaiseErrorPass() : Pass("raise_error", "raise errors from attributes") { }
+	void help() override
+	{
+		//   |---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|---v---|
+		log("\n");
+		log("    raise_error [selection]\n");
+		log("\n");
+		log("Test error handling by raising arbitrary errors. This pass iterates over the\n");
+		log("design (or selection of it) checking for objects with the 'raise_error'\n");
+		log("attribute set.\n");
+		log("\n");
+	}
+	void execute(vector<string> args, RTLIL::Design *design) override
+	{
+		log_header(design, "Executing RAISE_ERROR pass.\n");
+
+		extra_args(args, 1, design, true);
+
+		RTLIL::NamedObject *err_obj = nullptr;
+		
+		for (auto mod : design->all_selected_modules()) {
+			if (mod->has_attribute(ID::raise_error)) {
+				err_obj = mod->clone();
+				break;
+			}
+			for (auto memb : mod->selected_members()) {
+				if (memb->has_attribute(ID::raise_error)) {
+					err_obj = memb;
+					break;
+				}
+			}
+			if (err_obj != nullptr) break;
+		}
+
+		if (err_obj != nullptr) {
+			log("Raising error from '%s'.\n", log_id(err_obj));
+			auto err_no = err_obj->attributes[ID::raise_error].as_int();
+			if (err_no < 256) {
+				log_flush();
+			#if defined(_MSC_VER)
+				_exit(err_no);
+			#else
+				_Exit(err_no);
+			#endif
+			} else {
+				auto err_msg = err_obj->get_string_attribute(ID::raise_error);
+				log_error("%s\n", err_msg.c_str());
+			}
+		} else {
+			log("'raise_error' attribute not found\n");
+		}
+	}
+} RaiseErrorPass;
+
+PRIVATE_NAMESPACE_END

tests/bugpoint/.gitignore

@@ -0,0 +1,2 @@
+*.il
+*.log

tests/bugpoint/err.ys

@@ -0,0 +1,27 @@
+read_verilog -noblackbox << EOF
+(* raise_error=7 *)
+module top();
+endmodule
+
+(* raise_error="help me" *)
+module other();
+endmodule
+
+module zzy();
+endmodule
+EOF
+select -assert-mod-count 3 =*
+design -stash read
+
+# raise_error with int exits with status
+design -load read
+bugpoint -yosys ../../yosys -command raise_error -expect-return 7
+select -assert-mod-count 1 =*
+select -assert-mod-count 1 top
+
+# raise_error with string prints message
+design -load read
+rename top abc
+bugpoint -yosys ../../yosys -command raise_error -grep "help me"
+select -assert-mod-count 1 =*
+select -assert-mod-count 1 other