diff --git a/Cargo.lock b/Cargo.lock
index d1b0db4..f89a67e 100644
--- a/Cargo.lock
+++ b/Cargo.lock
@@ -126,9 +126,8 @@ name = "cst-to-llhd"
 version = "0.1.0"
 dependencies = [
  "clap",
+ "indexmap",
  "json",
- "linked-hash-map",
- "linked_hash_set",
  "llhd",
  "log",
  "num",
@@ -155,6 +154,12 @@ dependencies = [
  "termcolor",
 ]
 
+[[package]]
+name = "hashbrown"
+version = "0.11.2"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "ab5ef0d4909ef3724cc8cce6ccc8572c5c817592e9285f5464f8e86f8bd3726e"
+
 [[package]]
 name = "hermit-abi"
 version = "0.1.19"
@@ -183,6 +188,16 @@ dependencies = [
  "quick-error",
 ]
 
+[[package]]
+name = "indexmap"
+version = "1.8.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "0f647032dfaa1f8b6dc29bd3edb7bbef4861b8b8007ebb118d6db284fd59f6ee"
+dependencies = [
+ "autocfg",
+ "hashbrown",
+]
+
 [[package]]
 name = "itertools"
 version = "0.9.0"
@@ -216,21 +231,6 @@ version = "0.2.121"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "efaa7b300f3b5fe8eb6bf21ce3895e1751d9665086af2d64b42f19701015ff4f"
 
-[[package]]
-name = "linked-hash-map"
-version = "0.5.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "7fb9b38af92608140b86b693604b9ffcc5824240a484d1ecd4795bacb2fe88f3"
-
-[[package]]
-name = "linked_hash_set"
-version = "0.1.4"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "47186c6da4d81ca383c7c47c1bfc80f4b95f4720514d860a5407aaf4233f9588"
-dependencies = [
- "linked-hash-map",
-]
-
 [[package]]
 name = "llhd"
 version = "0.16.0"
diff --git a/Cargo.toml b/Cargo.toml
index 2464b4e..5555e2e 100644
--- a/Cargo.toml
+++ b/Cargo.toml
@@ -12,8 +12,7 @@ llhd = "*"
 log = "*"
 num = "0.3.1"
 num-bigint = "0.3.3"
-linked_hash_set = "*"
-linked-hash-map = "*"
+indexmap = "*"
 pretty_env_logger = "0.4"
 
 [[bin]]
diff --git a/src/cst/always_statement.rs b/src/cst/always_statement.rs
index 90fd66c..c5107c0 100644
--- a/src/cst/always_statement.rs
+++ b/src/cst/always_statement.rs
@@ -1,9 +1,9 @@
 use crate::{
     cst::{Expression, ModuleContext, Statement, SymbolKind, Tag, UnitContext},
-    tools::Tools,
+    tools::{EventControl, Tools},
 };
+use indexmap::{map::IndexMap, set::IndexSet};
 use json::JsonValue;
-use linked_hash_map::LinkedHashMap as HashMap;
 use llhd::{
     ir::{Signature, UnitId, UnitKind, UnitName, Value},
     ty::{int_ty, signal_ty},
@@ -55,41 +55,44 @@ impl AlwaysStatement {
             (json_event_control[0], &json_children[1])
         };
 
-        // first traversal
-        assert!(context.unit_ctx.is_empty());
-        Self::gen_event_expression_list(json_event_expression_list, context);
-        Statement::codegen(json_statement, context);
+        let proc_names = EventControl::process_names(json);
 
         assert!(context.unit_ctx.raw_name_to_arg.is_empty());
         let proc_signature = {
-            let mut ret = Signature::new();
+            let mut sig = Signature::new();
 
-            for lvalue in &context.unit_ctx.lvalues {
+            for lvalue in &proc_names.lvalues {
                 if context.symbol.contains_key(lvalue) {
                     let symbol = &context.symbol[lvalue];
                     assert_ne!(symbol.kind, SymbolKind::Param);
 
                     let width = symbol.value.width.clone();
-                    let arg = ret.add_output(signal_ty(int_ty(width)));
+                    let arg = sig.add_output(signal_ty(int_ty(width)));
                     context.unit_ctx.raw_name_to_arg.insert(lvalue.clone(), arg);
                 } else {
                     error!("FIXME: symbol '{}' not found", lvalue);
                 }
             }
 
-            let rvalues: Vec<String> = context
-                .unit_ctx
-                .rvalues
-                .iter()
-                .filter(|&x| !context.unit_ctx.lvalues.contains(x))
-                .map(|x| x.clone())
+            let mut rvalues = [
+                proc_names.posedges.clone(),
+                proc_names.negedges.clone(),
+                proc_names.levels.clone(),
+                proc_names.ctrl_values.clone(),
+                proc_names.rvalues.clone(),
+            ]
+            .iter()
+            .fold(IndexSet::new(), |acc, hs| acc.union(hs).cloned().collect());
+            rvalues = rvalues
+                .into_iter()
+                .filter(|x| !proc_names.lvalues.contains(x))
                 .collect();
             for rvalue in &rvalues {
                 if context.symbol.contains_key(rvalue) {
                     let symbol = &context.symbol[rvalue];
                     if symbol.kind != SymbolKind::Param {
                         let width = symbol.value.width.clone();
-                        let arg = ret.add_input(signal_ty(int_ty(width)));
+                        let arg = sig.add_input(signal_ty(int_ty(width)));
                         context.unit_ctx.raw_name_to_arg.insert(rvalue.clone(), arg);
                     }
                 } else {
@@ -97,7 +100,7 @@ impl AlwaysStatement {
                 }
             }
 
-            ret
+            sig
         };
 
         context.unit_ctx.new_data(
@@ -110,8 +113,15 @@ impl AlwaysStatement {
             proc_signature,
         );
 
-        // second traversal
-        Self::gen_event_expression_list(json_event_expression_list, context);
+        Self::gen_event_expression_list(
+            json_event_expression_list,
+            proc_names
+                .rvalues
+                .union(&proc_names.ctrl_values)
+                .cloned()
+                .collect(),
+            context,
+        );
         Statement::codegen(json_statement, context);
 
         Tools::beautify(&mut context.unit_ctx);
@@ -120,8 +130,12 @@ impl AlwaysStatement {
         context.module.add_unit(context.unit_ctx.drop_data())
     }
 
-    fn gen_event_expression_list<'a>(json: &'a JsonValue, context: &mut ModuleContext<'a>) {
-        let mut sensitivity_list = HashMap::new();
+    fn gen_event_expression_list<'a>(
+        json: &'a JsonValue,
+        rvalues: IndexSet<String>,
+        context: &mut ModuleContext<'a>,
+    ) {
+        let mut sensitivity_list = IndexMap::new();
 
         let json_expressions = Tools::match_tags(
             vec![json],
@@ -133,18 +147,15 @@ impl AlwaysStatement {
 
             match json_children[0]["tag"].as_str() {
                 Some(Tag::POS_EDGE) => {
-                    let symbol =
-                        Expression::gen_reference_name(&json_children[1]["children"][0], context);
+                    let symbol = Expression::gen_reference_name(&json_children[1]["children"][0]);
                     sensitivity_list.insert(symbol, Tag::POS_EDGE);
                 }
                 Some(Tag::NEG_EDGE) => {
-                    let symbol =
-                        Expression::gen_reference_name(&json_children[1]["children"][0], context);
+                    let symbol = Expression::gen_reference_name(&json_children[1]["children"][0]);
                     sensitivity_list.insert(symbol, Tag::NEG_EDGE);
                 }
                 Some(Tag::EXPRESSION) => {
-                    let symbol =
-                        Expression::gen_reference_name(&json_children[0]["children"][0], context);
+                    let symbol = Expression::gen_reference_name(&json_children[0]["children"][0]);
                     sensitivity_list.insert(symbol, Tag::EVENT_EXPRESSION);
                 }
                 _ => panic!("unknown error at CST node '{}'", json),
@@ -156,12 +167,11 @@ impl AlwaysStatement {
             let raw_name_to_value = &mut unit_ctx.raw_name_to_value;
             let raw_name_to_shadow = &mut unit_ctx.raw_name_to_shadow;
             let raw_name_to_arg = &unit_ctx.raw_name_to_arg;
-            let rvalues = &unit_ctx.rvalues;
 
             let mut builder = UnitContext::builder(&mut unit_ctx.data);
 
-            let mut arg_value_to_raw_name = HashMap::new();
-            let mut raw_name_to_prb_init = HashMap::new();
+            let mut arg_value_to_raw_name = IndexMap::new();
+            let mut raw_name_to_prb_init = IndexMap::new();
             for (name, arg) in raw_name_to_arg {
                 let value = builder.arg_value(*arg);
                 context
@@ -202,9 +212,9 @@ impl AlwaysStatement {
             builder.append_to(bb_init);
             let inputs: Vec<Value> = builder.unit().input_args().collect();
             let events: Vec<Value> = inputs
-                .iter()
-                .filter(|x| sensitivity_list.contains_key(&arg_value_to_raw_name[&x]))
-                .map(|&x| {
+                .into_iter()
+                .filter(|&x| sensitivity_list.contains_key(&arg_value_to_raw_name[&x]))
+                .map(|x| {
                     let raw_name = &arg_value_to_raw_name[&x];
                     let prb = builder.ins().prb(x);
                     raw_name_to_prb_init.insert(raw_name, prb);
diff --git a/src/cst/context.rs b/src/cst/context.rs
index 668d07f..00fed4f 100644
--- a/src/cst/context.rs
+++ b/src/cst/context.rs
@@ -1,6 +1,5 @@
+use indexmap::map::IndexMap;
 use json::JsonValue;
-use linked_hash_map::LinkedHashMap;
-use linked_hash_set::LinkedHashSet;
 use llhd::{
     ir::{
         Arg, Block, Inst, Module, Signature, Unit, UnitBuilder, UnitData, UnitKind, UnitName, Value,
@@ -13,15 +12,12 @@ use std::{collections::HashMap, fmt};
 pub struct ModuleContext<'a> {
     pub name: String,
     pub module: Module,
-    pub symbol: LinkedHashMap<String, SymbolInfo<'a>>,
+    pub symbol: IndexMap<String, SymbolInfo<'a>>,
     pub unit_ctx: UnitContext,
     pub syntax_table: SyntaxTable<'a>,
 }
 
 pub struct UnitContext {
-    pub lvalues: LinkedHashSet<String>,
-    pub rvalues: LinkedHashSet<String>,
-
     pub data: Option<UnitData>,
 
     pub raw_name_to_arg: HashMap<String, Arg>,
@@ -71,7 +67,7 @@ impl<'a> ModuleContext<'a> {
         Self {
             name: String::new(),
             module: Module::new(),
-            symbol: LinkedHashMap::new(),
+            symbol: IndexMap::new(),
             unit_ctx: UnitContext::new(),
             syntax_table: SyntaxTable::new(json),
         }
@@ -81,8 +77,6 @@ impl<'a> ModuleContext<'a> {
 impl UnitContext {
     pub fn new() -> Self {
         Self {
-            lvalues: LinkedHashSet::new(),
-            rvalues: LinkedHashSet::new(),
             data: None,
             raw_name_to_arg: HashMap::new(),
             raw_name_to_value: HashMap::new(),
@@ -93,8 +87,6 @@ impl UnitContext {
     }
     pub fn drop(&mut self) -> Self {
         let ret = Self {
-            lvalues: self.lvalues.iter().map(|x| x.clone()).collect(),
-            rvalues: self.rvalues.iter().map(|x| x.clone()).collect(),
             data: self.data.take(),
             raw_name_to_arg: self.raw_name_to_arg.drain().collect(),
             raw_name_to_value: self.raw_name_to_value.drain().collect(),
@@ -114,8 +106,6 @@ impl UnitContext {
     }
 
     pub fn clear(&mut self) {
-        self.lvalues.clear();
-        self.rvalues.clear();
         self.raw_name_to_arg.clear();
         self.raw_name_to_value.clear();
         self.raw_name_to_shadow.clear();
@@ -125,8 +115,6 @@ impl UnitContext {
 
     pub fn is_empty(&self) -> bool {
         self.data.is_none()
-            && self.lvalues.is_empty()
-            && self.rvalues.is_empty()
             && self.raw_name_to_arg.is_empty()
             && self.raw_name_to_value.is_empty()
             && self.raw_name_to_shadow.is_empty()
diff --git a/src/cst/expression.rs b/src/cst/expression.rs
index 0d79e4d..0da4877 100644
--- a/src/cst/expression.rs
+++ b/src/cst/expression.rs
@@ -15,8 +15,8 @@ use log::{debug, error, info, trace, warn};
 pub struct Expression {}
 
 impl Expression {
-    pub fn gen_reference_name(json: &JsonValue, context: &mut ModuleContext) -> String {
-        Self::gen_reference_call(json, context).0
+    pub fn gen_reference_name(json: &JsonValue) -> String {
+        Self::gen_reference_call(json).0
     }
 
     pub fn codegen<'a>(json: &'a JsonValue, context: &mut ModuleContext<'a>) -> Option<Value> {
@@ -44,10 +44,7 @@ impl Expression {
         }
     }
 
-    fn gen_reference_call(
-        json: &JsonValue,
-        context: &mut ModuleContext,
-    ) -> (String, Option<(usize, usize)>) {
+    fn gen_reference_call(json: &JsonValue) -> (String, Option<(usize, usize)>) {
         let json_symbol_identifier = Tools::match_tags(
             vec![json],
             vec![
@@ -97,13 +94,12 @@ impl Expression {
         };
 
         let symbol = &json_symbol_identifier[0]["text"];
-        context.unit_ctx.rvalues.insert(symbol.to_string());
 
         (symbol.to_string(), range)
     }
 
     fn gen_reference_value(json: &JsonValue, context: &mut ModuleContext) -> Option<Value> {
-        let (symbol, range) = Self::gen_reference_call(json, context);
+        let (symbol, range) = Self::gen_reference_call(json);
 
         if context.unit_ctx.data.is_some() {
             let unit_ctx = &mut context.unit_ctx;
diff --git a/src/cst/module_declaration.rs b/src/cst/module_declaration.rs
index c1a9cae..f1a85e7 100644
--- a/src/cst/module_declaration.rs
+++ b/src/cst/module_declaration.rs
@@ -259,7 +259,7 @@ impl<'a> ModuleDeclaration {
                             named_port_symbol_path.to_vec(),
                         );
                         if json_symbol.len() == 1 {
-                            let symbol = &Expression::gen_reference_name(json_symbol[0], context);
+                            let symbol = &Expression::gen_reference_name(json_symbol[0]);
                             Some(context.unit_ctx.raw_name_to_value[symbol])
                         } else {
                             let json_number = Tools::match_tags(
@@ -303,7 +303,7 @@ impl<'a> ModuleDeclaration {
                         .enumerate()
                     {
                         let json_expr = pos_port_list[&index];
-                        let arg = &Expression::gen_reference_name(json_expr, context);
+                        let arg = &Expression::gen_reference_name(json_expr);
                         let v = context.unit_ctx.raw_name_to_value[arg];
                         if arg_info.kind == SymbolKind::Input {
                             inputs.push(v);
diff --git a/src/cst/net_variable_assignment.rs b/src/cst/net_variable_assignment.rs
index bbaf9ea..dd0a089 100644
--- a/src/cst/net_variable_assignment.rs
+++ b/src/cst/net_variable_assignment.rs
@@ -43,7 +43,6 @@ impl NetVariableAssignment {
         };
 
         let lvalue_name = &json_lpvalue["text"].to_string();
-        context.unit_ctx.lvalues.insert(lvalue_name.clone());
         let lvalue = context.unit_ctx.raw_name_to_value.get(lvalue_name);
         if lvalue.is_some() {
             assert!(context.unit_ctx.data.is_some());
diff --git a/src/cst/nonblocking_assignment_statement.rs b/src/cst/nonblocking_assignment_statement.rs
index 51a9571..dd27991 100644
--- a/src/cst/nonblocking_assignment_statement.rs
+++ b/src/cst/nonblocking_assignment_statement.rs
@@ -36,7 +36,6 @@ impl NonblockingAssignmentStatement {
             (json_symbol_identifier[0], &json_children[2])
         };
         let lvalue_name = &json_lpvalue["text"].to_string();
-        context.unit_ctx.lvalues.insert(lvalue_name.clone());
         if context.unit_ctx.raw_name_to_value.contains_key(lvalue_name) {
             assert!(context.unit_ctx.raw_name_to_arg.contains_key(lvalue_name));
             assert!(context.unit_ctx.data.is_some());
diff --git a/src/tools/code_reporter.rs b/src/tools/code_reporter.rs
new file mode 100644
index 0000000..e71226b
--- /dev/null
+++ b/src/tools/code_reporter.rs
@@ -0,0 +1,67 @@
+use std::{
+    fs::File,
+    io::{BufRead, BufReader},
+};
+
+#[allow(unused_imports)]
+use log::{debug, error, info, trace, warn};
+
+pub struct CodeReporter {
+    file_name: String,
+    line_breakers: Vec<usize>,
+}
+
+impl CodeReporter {
+    pub fn new(file_name: &str) -> Self {
+        Self {
+            file_name: file_name.to_string(),
+            line_breakers: Self::read_line_breakers(file_name),
+        }
+    }
+
+    pub fn line_no(&self, key: usize) -> usize {
+        self.line_no_rec(key, 0, self.line_breakers.len() - 1)
+    }
+
+    pub fn line(&self, line_no: usize) -> String {
+        let reader = BufReader::new(
+            File::open(self.file_name.as_str())
+                .expect(format!(r#"file "{}" not found"#, self.file_name.as_str()).as_str()),
+        );
+
+        reader.lines().nth(line_no).unwrap().unwrap()
+    }
+
+    pub fn line_count(&self) -> usize {
+        self.line_breakers.len()
+    }
+
+    fn read_line_breakers(file_name: &str) -> Vec<usize> {
+        let reader = BufReader::new(
+            File::open(file_name).expect(format!(r#"file "{}" not found"#, file_name).as_str()),
+        );
+
+        let mut line_breakers = Vec::new();
+        line_breakers.push(0);
+
+        for line in reader.lines() {
+            let line_no = 1 + line_breakers.last().unwrap() + line.unwrap().len();
+            line_breakers.push(line_no);
+        }
+
+        line_breakers
+    }
+
+    fn line_no_rec(&self, key: usize, left: usize, right: usize) -> usize {
+        if left + 1 >= right {
+            left
+        } else {
+            let mid = (left + right) / 2;
+            if key < self.line_breakers[mid] {
+                self.line_no_rec(key, left, mid)
+            } else {
+                self.line_no_rec(key, mid, right)
+            }
+        }
+    }
+}
diff --git a/src/tools/event_control.rs b/src/tools/event_control.rs
index 94ed2c6..7d13333 100644
--- a/src/tools/event_control.rs
+++ b/src/tools/event_control.rs
@@ -1,54 +1,74 @@
 use crate::{cst::Tag, tools::Tools};
+use indexmap::set::IndexSet;
 use json::JsonValue;
-use std::{collections::HashSet, iter::FromIterator};
+use std::iter::FromIterator;
 
 #[allow(unused_imports)]
 use log::{debug, error, info, trace, warn};
 
+pub struct ProcessNames {
+    pub posedges: IndexSet<String>,
+    pub negedges: IndexSet<String>,
+    pub levels: IndexSet<String>,
+    pub lvalues: IndexSet<String>,
+    pub rvalues: IndexSet<String>,
+    pub ctrl_values: IndexSet<String>,
+}
+
+impl ProcessNames {
+    pub fn new() -> Self {
+        Self {
+            posedges: IndexSet::new(),
+            negedges: IndexSet::new(),
+            levels: IndexSet::new(),
+            lvalues: IndexSet::new(),
+            rvalues: IndexSet::new(),
+            ctrl_values: IndexSet::new(),
+        }
+    }
+}
+
 pub struct EventControl {}
 
 impl EventControl {
-    pub fn clock_and_reset_names(json: &JsonValue) -> (HashSet<String>, HashSet<String>) {
-        let mut clock_names: HashSet<String> = HashSet::new();
-        let mut reset_names: HashSet<String> = HashSet::new();
+    pub fn clock_and_reset_names(json: &JsonValue) -> (IndexSet<String>, IndexSet<String>) {
+        let mut clock_names: IndexSet<String> = IndexSet::new();
+        let mut reset_names: IndexSet<String> = IndexSet::new();
 
         let json_always_statements = Tools::collect_tag(json, Tag::ALWAYS_STATEMENT);
 
         for json_always_statement in json_always_statements {
             let (json_events, json_body) = Self::events_and_body(json_always_statement);
 
-            let (json_posedge_names, json_negedge_names, json_level_names) =
-                Self::event_names(json_events);
+            let (posedge_names, negedge_names, level_names) = Self::event_names(json_events);
 
-            let (json_lvalues, json_rvalues, json_ctrl_values) = Self::value_names(json_body);
-            let json_top_ctrl_values = Self::top_ctrl_values(json_body);
+            let (lvalues, rvalues, ctrl_values) = Self::value_names(json_body);
+            let top_ctrl_values = Self::top_ctrl_values(json_body);
 
-            let json_edge_names = [json_posedge_names.clone(), json_negedge_names.clone()].concat();
-            let json_sens_names = [json_edge_names.clone(), json_level_names.clone()].concat();
+            let edge_names: IndexSet<_> = posedge_names.union(&negedge_names).cloned().collect();
+            let sens_names: IndexSet<_> = edge_names.union(&level_names).cloned().collect();
 
-            let json_data_values: HashSet<String> =
-                json_lvalues.union(&json_rvalues).cloned().collect();
-            let json_all_values: HashSet<String> =
-                json_data_values.union(&json_ctrl_values).cloned().collect();
+            let data_values: IndexSet<String> = lvalues.union(&rvalues).cloned().collect();
+            let all_values: IndexSet<String> = data_values.union(&ctrl_values).cloned().collect();
 
-            let local_clock_names: HashSet<String> = HashSet::from_iter(
-                json_edge_names
+            let local_clock_names: IndexSet<String> = IndexSet::from_iter(
+                edge_names
                     .clone()
                     .into_iter()
-                    .filter(|x| !json_all_values.contains(x)),
+                    .filter(|x| !all_values.contains(x)),
             );
-            let local_reset_names: HashSet<String> = HashSet::from_iter(
-                json_sens_names
+            let local_reset_names: IndexSet<String> = IndexSet::from_iter(
+                sens_names
                     .clone()
                     .into_iter()
-                    .filter(|x| !json_data_values.contains(x) && json_top_ctrl_values.contains(x)),
+                    .filter(|x| !data_values.contains(x) && top_ctrl_values.contains(x)),
             );
 
-            trace!("edge_names {:?}", json_edge_names);
-            trace!("sens_names {:?}", json_sens_names);
-            trace!("data_values {:?}", json_data_values);
-            trace!("all_values {:?}", json_all_values);
-            trace!("top_ctrl_values {:?}", json_top_ctrl_values);
+            trace!("edge_names {:?}", edge_names);
+            trace!("sens_names {:?}", sens_names);
+            trace!("data_values {:?}", data_values);
+            trace!("all_values {:?}", all_values);
+            trace!("top_ctrl_values {:?}", top_ctrl_values);
 
             clock_names = clock_names.union(&local_clock_names).cloned().collect();
             reset_names = reset_names.union(&local_reset_names).cloned().collect();
@@ -59,6 +79,24 @@ impl EventControl {
         (clock_names, reset_names)
     }
 
+    pub fn process_names(json_always_statement: &JsonValue) -> ProcessNames {
+        let (json_events, json_body) = Self::events_and_body(json_always_statement);
+
+        let (posedge_names, negedge_names, level_names) = Self::event_names(json_events);
+
+        let (lvalues, rvalues, ctrl_values) = Self::value_names(json_body);
+
+        let mut names = ProcessNames::new();
+        names.posedges = posedge_names;
+        names.negedges = negedge_names;
+        names.levels = level_names;
+        names.lvalues = lvalues.into_iter().collect();
+        names.rvalues = rvalues.into_iter().collect();
+        names.ctrl_values = ctrl_values.into_iter().collect();
+
+        names
+    }
+
     fn events_and_body(json: &JsonValue) -> (Vec<&JsonValue>, &JsonValue) {
         assert_eq!(json["tag"], Tag::ALWAYS_STATEMENT);
         let (json_events, json_body) = {
@@ -90,10 +128,12 @@ impl EventControl {
         (json_events, json_body)
     }
 
-    fn event_names(json_events: Vec<&JsonValue>) -> (Vec<String>, Vec<String>, Vec<String>) {
-        let mut json_posedge_names = Vec::new();
-        let mut json_negedge_names = Vec::new();
-        let mut json_level_names = Vec::new();
+    fn event_names(
+        json_events: Vec<&JsonValue>,
+    ) -> (IndexSet<String>, IndexSet<String>, IndexSet<String>) {
+        let mut posedge_names = IndexSet::new();
+        let mut negedge_names = IndexSet::new();
+        let mut level_names = IndexSet::new();
 
         let json_id = |x: &JsonValue| -> String {
             let json_symbol_identifiers = Tools::collect_tag(&x, Tag::SYMBOL_IDENTIFIER);
@@ -104,20 +144,22 @@ impl EventControl {
         for json_event in json_events {
             match json_event["children"][0]["tag"].as_str() {
                 Some(Tag::POS_EDGE) => {
-                    json_posedge_names.push(json_id(json_event));
+                    posedge_names.insert(json_id(json_event));
                 }
                 Some(Tag::NEG_EDGE) => {
-                    json_negedge_names.push(json_id(json_event));
+                    negedge_names.insert(json_id(json_event));
                 }
                 _ => {
-                    json_level_names.push(json_id(json_event));
+                    level_names.insert(json_id(json_event));
                 }
             }
         }
-        (json_posedge_names, json_negedge_names, json_level_names)
+        (posedge_names, negedge_names, level_names)
     }
 
-    fn value_names(json_body: &JsonValue) -> (HashSet<String>, HashSet<String>, HashSet<String>) {
+    fn value_names(
+        json_body: &JsonValue,
+    ) -> (IndexSet<String>, IndexSet<String>, IndexSet<String>) {
         let json_assignments = [
             Tools::collect_tag(json_body, Tag::NONBLOCKING_ASSIGNMENT_STATEMENT),
             Tools::collect_tag(json_body, Tag::NET_VARIABLE_ASSIGNMENT),
@@ -136,21 +178,21 @@ impl EventControl {
         ]
         .concat();
 
-        let json_lvalues = HashSet::from_iter(
+        let json_lvalues = IndexSet::from_iter(
             json_assignments
                 .iter()
                 .map(|x| Tools::collect_tag(&x["children"][0], Tag::SYMBOL_IDENTIFIER))
                 .flatten()
                 .map(|x| x["text"].to_string()),
         );
-        let json_rvalues = HashSet::from_iter(
+        let json_rvalues = IndexSet::from_iter(
             json_assignments
                 .iter()
                 .map(|x| Tools::collect_tag(&x["children"][2], Tag::SYMBOL_IDENTIFIER))
                 .flatten()
                 .map(|x| x["text"].to_string()),
         );
-        let json_ctrl_values = HashSet::from_iter(
+        let json_ctrl_values = IndexSet::from_iter(
             json_conditions
                 .iter()
                 .map(|x| Tools::collect_tag(x, Tag::SYMBOL_IDENTIFIER))
@@ -161,7 +203,7 @@ impl EventControl {
         (json_lvalues, json_rvalues, json_ctrl_values)
     }
 
-    fn top_ctrl_values(json_body: &JsonValue) -> HashSet<String> {
+    fn top_ctrl_values(json_body: &JsonValue) -> IndexSet<String> {
         let json_statement = {
             let mut ret = json_body;
             loop {
@@ -182,7 +224,7 @@ impl EventControl {
                 }
             }
         };
-        HashSet::from_iter(
+        IndexSet::from_iter(
             Tools::match_tags(
                 vec![json_statement],
                 vec![
diff --git a/src/tools/mod.rs b/src/tools/mod.rs
index 80cea7b..bf194ff 100644
--- a/src/tools/mod.rs
+++ b/src/tools/mod.rs
@@ -1,5 +1,7 @@
+pub mod code_reporter;
 pub mod event_control;
-mod tools;
+pub mod tools;
 
-pub use event_control::EventControl;
-pub use tools::{CodeReporter, Tools};
+pub use code_reporter::CodeReporter;
+pub use event_control::{EventControl, ProcessNames};
+pub use tools::Tools;
diff --git a/src/tools/tools.rs b/src/tools/tools.rs
index 8fc5cf6..bf5925c 100644
--- a/src/tools/tools.rs
+++ b/src/tools/tools.rs
@@ -4,8 +4,6 @@ use llhd::ir::{Block, Inst, Opcode};
 use std::{
     cell::RefCell,
     collections::{HashMap, HashSet, VecDeque},
-    fs::File,
-    io::{BufRead, BufReader},
     iter::FromIterator,
     process::{Command, Stdio},
     rc::Rc,
@@ -279,63 +277,3 @@ impl Tools {
         modules
     }
 }
-
-pub struct CodeReporter {
-    file_name: String,
-    line_breakers: Vec<usize>,
-}
-
-impl CodeReporter {
-    pub fn new(file_name: &str) -> Self {
-        Self {
-            file_name: file_name.to_string(),
-            line_breakers: Self::read_line_breakers(file_name),
-        }
-    }
-
-    pub fn line_no(&self, key: usize) -> usize {
-        self.line_no_rec(key, 0, self.line_breakers.len() - 1)
-    }
-
-    pub fn line(&self, line_no: usize) -> String {
-        let reader = BufReader::new(
-            File::open(self.file_name.as_str())
-                .expect(format!(r#"file "{}" not found"#, self.file_name.as_str()).as_str()),
-        );
-
-        reader.lines().nth(line_no).unwrap().unwrap()
-    }
-
-    pub fn line_count(&self) -> usize {
-        self.line_breakers.len()
-    }
-
-    fn read_line_breakers(file_name: &str) -> Vec<usize> {
-        let reader = BufReader::new(
-            File::open(file_name).expect(format!(r#"file "{}" not found"#, file_name).as_str()),
-        );
-
-        let mut line_breakers = Vec::new();
-        line_breakers.push(0);
-
-        for line in reader.lines() {
-            let line_no = 1 + line_breakers.last().unwrap() + line.unwrap().len();
-            line_breakers.push(line_no);
-        }
-
-        line_breakers
-    }
-
-    fn line_no_rec(&self, key: usize, left: usize, right: usize) -> usize {
-        if left + 1 >= right {
-            left
-        } else {
-            let mid = (left + right) / 2;
-            if key < self.line_breakers[mid] {
-                self.line_no_rec(key, left, mid)
-            } else {
-                self.line_no_rec(key, mid, right)
-            }
-        }
-    }
-}