diff --git a/src/code_generator/symbol_table.c b/src/code_generator/symbol_table.c
index 55177f44..1100f6d2 100644
--- a/src/code_generator/symbol_table.c
+++ b/src/code_generator/symbol_table.c
@@ -1,12 +1,12 @@
 #include "code_generator/symbol_table.h"
 #include "code_generator/symbol_table_impl.h"
-#include "stdstring.h"
 #include "utility.h"
 
 DEFINE_VECTOR(SymbolInfoRef)
 DEFINE_VECTOR(SymbolBlockRef)
 
 static SymbolTableRef g_symbol_table;
+static const char g_separator = '$';
 
 SymbolInfoRef symbol_info_ctor(StringRef name, LLVMTypeRef type,
                                LLVMValueRef value) {
@@ -84,3 +84,73 @@ void finalize_symbol_table(void) {
   assert(g_symbol_table);
   symbol_table_dtor(&g_symbol_table);
 }
+
+void symbol_table_push(StringRef name) {
+  const SymbolBlockRef block = symbol_block_ctor(name);
+  VECTORFUNC(SymbolBlockRef, push_back)(g_symbol_table->stack, block);
+  string_append(g_symbol_table->prefix, name);
+  string_push_back(g_symbol_table->prefix, g_separator);
+}
+
+void symbol_table_pop(void) {
+  const size_t length = string_length(g_symbol_table->prefix);
+  assert(2 <= length);
+  assert(!VECTORFUNC(SymbolBlockRef, empty)(g_symbol_table->stack));
+  {
+    SymbolBlockRef block =
+        VECTORFUNC(SymbolBlockRef, back)(g_symbol_table->stack);
+    symbol_block_dtor(&block);
+    VECTORFUNC(SymbolBlockRef, pop_back)(g_symbol_table->stack);
+  }
+  {
+    size_t i = length - 1;
+    for (; 0 < i; --i) {
+      if (string_at(g_symbol_table->prefix, i - 1) == g_separator) {
+        break;
+      }
+    }
+    string_erase(g_symbol_table->prefix, i, length - i);
+  }
+}
+
+void register_symbol(StringRef name, LLVMTypeRef type, LLVMValueRef value) {
+  const SymbolInfoRef symbol = symbol_info_ctor(name, type, value);
+  const SymbolBlockRef block =
+      VECTORFUNC(SymbolBlockRef, back)(g_symbol_table->stack);
+  VECTORFUNC(SymbolInfoRef, push_back)(block->symbols, symbol);
+}
+
+void append_prefix(StringRef name) {
+  string_insert(name, 0, g_symbol_table->prefix);
+}
+
+static SymbolInfoRef find_symbol_in_block(StringRef name,
+                                          SymbolBlockRef block) {
+  const SymbolInfoRef* const begin =
+      VECTORFUNC(SymbolInfoRef, begin)(block->symbols);
+  const SymbolInfoRef* const end =
+      VECTORFUNC(SymbolInfoRef, end)(block->symbols);
+  const SymbolInfoRef* iter = begin;
+  for (; iter != end; ++iter) {
+    if (string_compare((*iter)->name, name) == 0) {
+      return *iter;
+    }
+  }
+  return NULL;
+}
+
+SymbolInfoRef find_symbol(StringRef name) {
+  const SymbolBlockRef* const begin =
+      VECTORFUNC(SymbolBlockRef, begin)(g_symbol_table->stack);
+  const SymbolBlockRef* const end =
+      VECTORFUNC(SymbolBlockRef, end)(g_symbol_table->stack);
+  const SymbolBlockRef* iter = end;
+  for (; iter != begin; --iter) {
+    const SymbolInfoRef symbol = find_symbol_in_block(name, *(iter - 1));
+    if (symbol) {
+      return symbol;
+    }
+  }
+  /* TODO: find global symbol */
+  return NULL;
+}
diff --git a/src/code_generator/symbol_table.h b/src/code_generator/symbol_table.h
index 25345a58..1d8b1e9b 100644
--- a/src/code_generator/symbol_table.h
+++ b/src/code_generator/symbol_table.h
@@ -1,11 +1,19 @@
 #ifndef KMC_C90_COMPILER_CODE_GENERATOR_SYMBOL_TABLE_H
 #define KMC_C90_COMPILER_CODE_GENERATOR_SYMBOL_TABLE_H
 
+#include <llvm-c/Core.h>
+#include "stdstring.h"
+
 typedef struct SymbolInfo* SymbolInfoRef;
 typedef struct SymbolBlock* SymbolBlockRef;
 typedef struct SymbolTable* SymbolTableRef;
 
 void initialize_symbol_table(StringRef name);
 void finalize_symbol_table(void);
+void symbol_table_push(StringRef name);
+void symbol_table_pop(void);
+void register_symbol(StringRef name, LLVMTypeRef type, LLVMValueRef value);
+void append_prefix(StringRef name);
+SymbolInfoRef find_symbol(StringRef name);
 
 #endif  /* KMC_C90_COMPILER_CODE_GENERATOR_SYMBOL_TABLE_H */