diff --git a/filter/Makefile b/filter/Makefile
index df7ff3f9..e3b7ec26 100644
--- a/filter/Makefile
+++ b/filter/Makefile
@@ -22,11 +22,10 @@ $(o)inst-gen.h: $(s)decl.m4 $(s)f-inst.c $(objdir)/.dir-stamp
 $(o)inst-gen.c: $(s)decl.m4 $(s)f-inst.c $(objdir)/.dir-stamp
 	$(M4) $(M4FLAGS_FILTERS) -DTARGET=C -P $^ >$@
 
-$(o)f-inst-dump.c: $(s)dump.m4 $(s)f-inst.c $(objdir)/.dir-stamp
-	$(M4) $(M4FLAGS_FILTERS) -P $^ >$@
-
-$(o)filter.o: $(o)f-inst-interpret.c $(o)f-inst-postfixify.c $(o)f-inst-same.c $(o)f-inst-dump.c $(o)inst-gen.h
+$(o)filter.o: $(o)f-inst-interpret.c $(o)f-inst-postfixify.c $(o)f-inst-same.c $(o)inst-gen.h
 
 tests_src := tree_test.c filter_test.c trie_test.c
 tests_targets := $(tests_targets) $(tests-target-files)
 tests_objs := $(tests_objs) $(src-o-files)
+
+$(call clean,inst-gen.h inst-gen.c)
diff --git a/filter/decl.m4 b/filter/decl.m4
index 9c35677e..6199d4be 100644
--- a/filter/decl.m4
+++ b/filter/decl.m4
@@ -10,6 +10,8 @@ m4_divert(-1)m4_dnl
 #	Global Diversions:
 #	4	enum fi_code
 #	5	enum fi_code to string
+#	6	dump line item
+#	7	dump line item callers
 #	1	struct f_inst_FI_...
 #	2	union in struct f_inst
 #	3	constructors
@@ -18,8 +20,10 @@ m4_divert(-1)m4_dnl
 #	101	content of struct f_inst_FI_...
 #	102	constructor arguments
 #	103	constructor body
+#	104	dump line item content
 #
-#	Put-around Diversions: 9xx
+#	Diversions for TARGET=C: 8xx
+#	Diversions for TARGET=H: 9xx
 
 # Flush the completed instruction
 m4_define(FID_END, `m4_divert(-1)')
@@ -32,10 +36,13 @@ m4_define(FID_UNION, `FID_ZONE(2, Union member)')
 m4_define(FID_NEW, `FID_ZONE(3, Constructor)')
 m4_define(FID_ENUM, `FID_ZONE(4, Code enum)')
 m4_define(FID_ENUM_STR, `FID_ZONE(5, Code enum to string)')
+m4_define(FID_DUMP, `FID_ZONE(6, Dump line)')
+m4_define(FID_DUMP_CALLER, `FID_ZONE(7, Dump line caller)')
 
 m4_define(FID_STRUCT_IN, `m4_divert(101)')
 m4_define(FID_NEW_ARGS, `m4_divert(102)')
 m4_define(FID_NEW_BODY, `m4_divert(103)')
+m4_define(FID_DUMP_BODY, `m4_divert(104)m4_define(FID_DUMP_BODY_EXISTS)')
 
 m4_define(FID_ALL, `m4_ifdef([[FID_CURDIV]], [[m4_divert(FID_CURDIV)m4_undefine([[FID_CURDIV]])]])')
 m4_define(FID_C, `m4_ifelse(TARGET, [[C]], FID_ALL, [[m4_define(FID_CURDIV, m4_divnum)m4_divert(-1)]])')
@@ -57,7 +64,9 @@ FID_NEW
 struct f_inst *f_new_inst_]]INST_NAME()[[(enum f_instruction_code fi_code
 m4_undivert(102)
 )
-FID_H ; FID_C
+FID_H
+;
+FID_C
 {
   struct f_inst *what_ = cfg_allocz(sizeof(struct f_inst));
   what_->fi_code = fi_code;
@@ -67,6 +76,19 @@ FID_H ; FID_C
 m4_undivert(103)
   return what_;
 }
+
+FID_DUMP_CALLER
+case INST_NAME(): f_dump_line_item_]]INST_NAME()[[(item, indent + 1); break;
+
+FID_DUMP
+m4_ifdef([[FID_DUMP_BODY_EXISTS]],
+[[static inline void f_dump_line_item_]]INST_NAME()[[(const struct f_line_item *item, const int indent)]]
+,
+[[static inline void f_dump_line_item_]]INST_NAME()[[(const struct f_line_item *item UNUSED, const int indent UNUSED)]])
+m4_undefine([[FID_DUMP_BODY_EXISTS]])
+{
+m4_undivert(104)
+}
 FID_ALL
 FID_END
 ]])')
@@ -80,23 +102,32 @@ FID_NEW_ARGS
 , $1 $2
 FID_NEW_BODY
 what->$2 = $2;
+m4_ifelse($3,,,[[
+FID_DUMP_BODY
+debug("%s$3\n", INDENT, $4);
+]])
 FID_END')
 
-m4_define(ARG, `FID_MEMBER(const struct f_inst *, f$1)
+m4_define(ARG, `FID_MEMBER(const struct f_inst *, f$1,,)
 FID_NEW_BODY
 for (const struct f_inst *child = f$1; child; child = child->next) what_->size += child->size;
 FID_END')
-m4_define(ARG_ANY, `FID_MEMBER(const struct f_inst *, f$1)
+m4_define(ARG_ANY, `FID_MEMBER(const struct f_inst *, f$1,,)
 FID_NEW_BODY
 for (const struct f_inst *child = f$1; child; child = child->next) what_->size += child->size;
 FID_END')
-m4_define(LINE, `FID_MEMBER(const struct f_inst *, f$1)')
+m4_define(LINE, `FID_MEMBER(const struct f_inst *, f$1,,)
+FID_DUMP_BODY
+f_dump_line(item->lines[$2], indent + 1);
+FID_END')
 m4_define(LINEP, `FID_STRUCT_IN
 const struct f_line *fl$1;
+FID_DUMP_BODY
+f_dump_line(item->lines[$2], indent + 1)
 FID_END')
-m4_define(SYMBOL, `FID_MEMBER(const struct symbol *, sym)')
-m4_define(VALI, `FID_MEMBER(struct f_val, vali)')
-m4_define(VALP, `FID_MEMBER(const struct f_val *, valp)')
+m4_define(SYMBOL, `FID_MEMBER(const struct symbol *, sym, symbol %s, item->sym->name)')
+m4_define(VALI, `FID_MEMBER(struct f_val, vali, value %s, val_dump(&item->val))')
+m4_define(VALP, `FID_MEMBER(const struct f_val *, valp, value %s, val_dump(&item->val))')
 m4_define(VAR, `m4_dnl
 FID_STRUCT_IN
 const struct f_val *valp;
@@ -105,39 +136,33 @@ FID_NEW_ARGS
 , const struct symbol *sym
 FID_NEW_BODY
 what->valp = (what->sym = sym)->def;
+FID_DUMP_BODY
+debug("%svariable %s with value %s\n", INDENT, item->sym->name, val_dump(item->vp));
 FID_END')
-m4_define(FRET, `FID_MEMBER(enum filter_return, fret)')
-m4_define(ECS, `FID_MEMBER(enum ec_subtype, ecs)')
-m4_define(RTC, `FID_MEMBER(const struct rtable_config *, rtc)')
+m4_define(FRET, `FID_MEMBER(enum filter_return, fret, %s, filter_return_str(item->fret))')
+m4_define(ECS, `FID_MEMBER(enum ec_subtype, ecs, ec subtype %s, ec_subtype_str(item->ecs))')
+m4_define(RTC, `FID_MEMBER(const struct rtable_config *, rtc, route table %s, item->rtc->name)')
 m4_define(STATIC_ATTR, `FID_MEMBER(struct f_static_attr, sa)')
 m4_define(DYNAMIC_ATTR, `FID_MEMBER(struct f_dynamic_attr, da)')
-m4_define(COUNT, `FID_MEMBER(uint, count)')
-m4_define(TREE, `FID_MEMBER(const struct f_tree *, tree)')
-m4_define(STRING, `FID_MEMBER(const char *, s)')
+m4_define(COUNT, `FID_MEMBER(uint, count, number %u, item->count)')
+m4_define(TREE, `FID_MEMBER(const struct f_tree *, tree, tree %p, item->tree)')
+m4_define(STRING, `FID_MEMBER(const char *, s, string \"%s\", item->s)')
 
-m4_define(FID_WR_UNDIVERT_LIST,FID_WR_DPUT(900))
-m4_define(FID_WR_CUR_DIRECT,900)
-m4_define(FID_WR_PUT, `m4_ifelse(1, m4_eval(m4_divnum > -1), [[m4_divert(-1)
-  m4_define([[FID_WR_CUR_DIRECT]], m4_eval(FID_WR_CUR_DIRECT + 1))
-  m4_define([[FID_WR_UNDIVERT_LIST]], FID_WR_UNDIVERT_LIST[[]]/* wrput $1 */FID_WR_DPUT($1)/* wrputdir FID_WR_CUR_DIRECT */FID_WR_DPUT(FID_WR_CUR_DIRECT))
-  m4_divert(FID_WR_CUR_DIRECT)]], [[m4_define([[FID_WR_UNDIVERT_LIST]], FID_WR_UNDIVERT_LIST[[]]/* wrdrop $1 */FID_WR_DROP($1))]])')
+m4_define(FID_WR_PUT_LIST)
+m4_define(FID_WR_DROP_LIST)
 
+m4_define(FID_WR_IPUT, `m4_define([[FID_WR_CUR_DIRECT]], m4_eval(FID_WR_CUR_DIRECT + 1))m4_define([[FID_WR_PUT_LIST]], FID_WR_PUT_LIST[[]]FID_WR_DPUT($1)FID_WR_DPUT(FID_WR_CUR_DIRECT))m4_divert(FID_WR_CUR_DIRECT)')
+m4_define(FID_WR_IDROP, `m4_define([[FID_WR_CUR_DIRECT]], m4_eval(FID_WR_CUR_DIRECT + 1))m4_define([[FID_WR_DROP_LIST]], FID_WR_DROP_LIST[[]]FID_WR_DPUT($1)FID_WR_DPUT(FID_WR_CUR_DIRECT))m4_divert(FID_WR_CUR_DIRECT)')
+
+m4_define(FID_WR_DIRECT, `m4_define([[FID_WR_CUR_DIRECT]],$1)m4_ifelse(TARGET,[[$2]],[[m4_define([[FID_WR_PUT]], [[FID_WR_IPUT($]][[@)]])m4_define([[FID_WR_PUT_LIST]],FID_WR_PUT_LIST[[]]FID_WR_DPUT($1))]],[[m4_define([[FID_WR_PUT]], [[FID_WR_IDROP($]][[@)]])m4_define([[FID_WR_DROP_LIST]],FID_WR_DROP_LIST[[]]FID_WR_DPUT($1))]])m4_divert($1)')
+
+m4_dnl m4_define(FID_WR_CUR_DIRECT,m4_ifelse(TARGET,`C',800,TARGET,`H',900,m4_errprint(`Bad TARGET: 'TARGET)m4_m4exit(1)))
 m4_changequote([[,]])
-m4_divert(900)
-FID_C
+FID_WR_DIRECT(800,C)
 #include "nest/bird.h"
 #include "filter/filter.h"
 #include "filter/f-inst.h"
 
-FID_H
-
-/* Filter instruction codes */
-enum f_instruction_code {
-FID_WR_PUT(4)
-};
-
-FID_C
-
 /* Instruction codes to string */
 static const char * const f_instruction_name_str[] = {
 FID_WR_PUT(5)
@@ -152,7 +177,39 @@ f_instruction_name(enum f_instruction_code fi)
     bug("Got unknown instruction code: %d", fi);
 }
 
-FID_H
+/* Instruction constructors */
+FID_WR_PUT(3)
+
+/* Line dumpers */
+#define INDENT (((const char *) f_dump_line_indent_str) + sizeof(f_dump_line_indent_str) - (indent) - 1)
+static const char f_dump_line_indent_str[] = "                                ";
+void f_dump_line(const struct f_line *dest, int indent);
+
+FID_WR_PUT(6)
+
+void f_dump_line(const struct f_line *dest, int indent)
+{
+  if (!dest) {
+    debug("%sNo filter line (NULL)\n", INDENT);
+    return;
+  }
+  debug("%sFilter line %p (len=%u)\n", INDENT, dest, dest->len);
+  for (uint i=0; i<dest->len; i++) {
+    const struct f_line_item *item = &dest->items[i];
+    debug("%sInstruction %s at line %u\n", INDENT, f_instruction_name(item->fi_code), item->lineno);
+    switch (item->fi_code) {
+FID_WR_PUT(7)
+      default: bug("Unknown instruction %x in f_dump_line", item->fi_code);
+    }
+  }
+  debug("%sFilter line %p dump done\n", INDENT, dest);
+}
+
+FID_WR_DIRECT(900,H)
+/* Filter instruction codes */
+enum f_instruction_code {
+FID_WR_PUT(4)
+};
 
 /* Per-instruction structures */
 FID_WR_PUT(1)
@@ -167,12 +224,12 @@ struct f_inst {
   };
 };
 
-FID_ALL
 /* Instruction constructors */
 FID_WR_PUT(3)
+
 m4_divert(-1)
 m4_changequote(`,')
 
-m4_m4wrap(`INST_FLUSH()m4_define(FID_WR_DPUT, [[m4_undivert($1)]])m4_define(FID_WR_DROP, [[m4_divert(-1)m4_undivert($1)m4_divert(0)]])m4_divert(0)FID_WR_UNDIVERT_LIST[[]]m4_divert(-1)')
+m4_m4wrap(`INST_FLUSH()m4_define(FID_WR_DPUT, [[m4_undivert($1)]])m4_divert(0)FID_WR_PUT_LIST[[]]m4_divert(-1)FID_WR_DROP_LIST[[]]')
 
 m4_changequote([[,]])
diff --git a/filter/dump.m4 b/filter/dump.m4
deleted file mode 100644
index 4ea3e3be..00000000
--- a/filter/dump.m4
+++ /dev/null
@@ -1,51 +0,0 @@
-m4_divert(-1)m4_dnl
-#
-#	BIRD -- Dumping instruction lines
-#
-#	(c) 2018 Maria Matejka <mq@jmq.cz>
-#
-#	Can be freely distributed and used under the terms of the GNU GPL.
-#
-
-# Common aliases
-m4_define(DNL, `m4_dnl')
-
-m4_define(INST_FLUSH, `m4_ifdef([[INST_NAME]], [[
-m4_divert(1)
-case INST_NAME():
-m4_undivert(2)
-break;
-m4_divert(-1)
-]])')
-m4_define(INST, `INST_FLUSH()m4_define([[INST_NAME]], [[$1]])')
-
-m4_define(LINE, `m4_divert(2)f_dump_line(item->lines[$2], indent + 1);
-m4_divert(-1)')
-m4_define(LINEP, `LINE($@)')
-m4_define(SYMBOL, `m4_divert(2)debug("%ssymbol %s\n", INDENT, item->sym->name);
-m4_divert(-1)')
-m4_define(VALI, `m4_divert(2)debug("%svalue %s\n", INDENT, val_dump(&item->val));
-m4_divert(-1)')
-m4_define(VAR, `m4_divert(2)debug("%svar %s: value %s\n", INDENT, item->sym->name, val_dump(item->vp));
-m4_divert(-1)')
-m4_define(FRET, `m4_divert(2)debug("%sfilter return value %d\n", INDENT, item->fret);
-m4_divert(-1)')
-m4_define(ECS, `m4_divert(2)debug("%sec subtype %d\n", INDENT, item->ecs);
-m4_divert(-1)')
-m4_define(RTC, `m4_divert(2)debug("%sroute table %s\n", INDENT, item->rtc->name);
-m4_divert(-1)')
-m4_define(STATIC_ATTR, `m4_divert(2)debug("%sstatic attribute %u/%u/%u\n", INDENT, item->sa.f_type, item->sa.sa_code, item->sa.readonly);
-m4_divert(-1)')
-m4_define(DYNAMIC_ATTR, `m4_divert(2)debug("%sdynamic attribute %u/%u/%u/%u\n", INDENT, item->da.type, item->da.bit, item->da.f_type, item->da.ea_code);
-m4_divert(-1)')
-m4_define(DUMP, `m4_divert(2)$1m4_divert(-1)')
-
-m4_m4wrap(`
-INST_FLUSH()
-m4_divert(0)DNL
-m4_undivert(1)
-
-default: bug( "Unknown instruction %d (%c)", item->fi_code, item->fi_code & 0xff);
-')
-
-m4_changequote([[,]])
diff --git a/filter/filter.c b/filter/filter.c
index ebd2e4dc..f08c91db 100644
--- a/filter/filter.c
+++ b/filter/filter.c
@@ -112,34 +112,6 @@ val_format_str(struct filter_state *fs, struct f_val *v) {
 
 static struct tbf rl_runtime_err = TBF_DEFAULT_LOG_LIMITS;
 
-#define INDENT (((const char *) f_dump_line_indent_str) + sizeof(f_dump_line_indent_str) - (indent) - 1)
-static const char f_dump_line_indent_str[] = "                                ";
-
-static void f_dump_line(const struct f_line *dest, int indent);
-
-static void
-f_dump_line_item(const struct f_line_item *item, int indent)
-{
-  debug("%sInstruction %s at line %u\n", INDENT, f_instruction_name(item->fi_code), item->lineno);
-  switch (item->fi_code) {
-#include "filter/f-inst-dump.c"
-  }
-}
-
-static void
-f_dump_line(const struct f_line *dest, int indent)
-{
-  if (!dest) {
-    debug("%sNo filter line (NULL)\n", INDENT);
-    return;
-  }
-  debug("%sFilter line %p (len=%u)\n", INDENT, dest, dest->len);
-  for (uint i=0; i<dest->len; i++)
-    f_dump_line_item(&dest->items[i], indent+1);
-  debug("%sFilter line %p dump done\n", INDENT, dest);
-#undef INDENT
-}
-
 static uint
 postfixify(struct f_line *dest, const struct f_inst *what_, uint pos)
 {
@@ -166,7 +138,7 @@ f_postfixify_concat(const struct f_inst * const inst[], uint count)
     out->len = postfixify(out, inst[i], out->len);
 
 #if DEBUGGING
-  f_dump_line(out, 0);
+//  f_dump_line(out, 0);
 #endif
   return out;
 }
diff --git a/filter/filter.h b/filter/filter.h
index 9f1a8e50..d03c6438 100644
--- a/filter/filter.h
+++ b/filter/filter.h
@@ -27,6 +27,21 @@ enum filter_return {
   F_QUITBIRD,
 };
 
+static inline const char *filter_return_str(const enum filter_return fret) {
+  switch (fret) {
+#define FRS(x) case x: return #x
+    FRS(F_NOP);
+    FRS(F_NONL);
+    FRS(F_RETURN);
+    FRS(F_ACCEPT);
+    FRS(F_REJECT);
+    FRS(F_ERROR);
+    FRS(F_QUITBIRD);
+#undef FRS
+    default: bug("This shall not happen");
+  }
+}
+
 struct f_val;
 
 /* The filter encapsulating structure to be pointed-to from outside */
diff --git a/nest/a-set.c b/nest/a-set.c
index 10ddd139..78922ffd 100644
--- a/nest/a-set.c
+++ b/nest/a-set.c
@@ -72,15 +72,12 @@ ec_format(byte *buf, u64 ec)
   char tbuf[16], *kind;
 
   type = ec >> 48;
-  switch (type & 0xf0ff)
-    {
-    case EC_RT: kind = "rt"; break;
-    case EC_RO: kind = "ro"; break;
+  kind = ec_subtype_str(type & 0xf0ff);
 
-    default:
-      kind = tbuf;
-      bsprintf(kind, "unknown 0x%x", type);
-    }
+  if (!kind) {
+    kind = tbuf;
+    bsprintf(kind, "unknown 0x%x", type);
+  }
 
   switch (ec >> 56)
     {
diff --git a/nest/attrs.h b/nest/attrs.h
index 37227d9b..4efcff79 100644
--- a/nest/attrs.h
+++ b/nest/attrs.h
@@ -125,6 +125,14 @@ enum ec_subtype {
   EC_GENERIC = 0xFFFF,
 };
 
+static inline const char *ec_subtype_str(const enum ec_subtype ecs) {
+  switch (ecs) {
+    case EC_RT: return "rt";
+    case EC_RO: return "ro";
+    default: return NULL;
+  }
+}
+
 /* Transitive bit (for first u32 half of EC) */
 #define EC_TBIT 0x40000000