Remove unused entries from the string table

.travis.yml

@@ -38,6 +38,13 @@ jobs:
       script: scripts/travis_lint.sh
       before_cache:
 
+    - &string-table-check
+      stage: Linter + Doxygen + non-debug Ubuntu/gcc-5 test
+      env: NAME="string-table"
+      install:
+      script: scripts/string_table_check.sh
+      before_cache:
+
     - stage: Linter + Doxygen + non-debug Ubuntu/gcc-5 test
       env: NAME="DOXYGEN-CHECK"
       addons:

scripts/string_table_check.sh

@@ -0,0 +1,30 @@
+#!/bin/bash
+
+whitelist=" \
+"
+
+cleanup()
+{
+  rm -f "$ids_file"
+}
+
+ids_file=$(mktemp)
+
+trap cleanup EXIT
+
+gcc -E -P -x c src/util/irep_ids.def \
+  -D'IREP_ID_ONE(x)=ID_ ## x' -D'IREP_ID_TWO(x,y)=ID_ ## x' > $ids_file
+
+for w in $whitelist
+do
+  perl -p -i -e "s/^$w\n//" $ids_file
+done
+
+for i in $(<$ids_file)
+do
+  if ! git grep -w -q -c -F $i
+  then
+    echo "$i is never used"
+    exit  1
+  fi
+done

src/cpp/cpp_typecheck_resolve.cpp

@@ -839,11 +839,11 @@ exprt cpp_typecheck_resolvet::do_builtin(
                             << ": " << original_scope->prefix
                             << messaget::eom;
   }
-  else if(base_name=="size_t")
+  else if(base_name == ID_size_t)
   {
     dest=type_exprt(size_type());
   }
-  else if(base_name=="ssize_t")
+  else if(base_name == ID_ssize_t)
   {
     dest=type_exprt(signed_size_type());
   }

src/goto-programs/remove_asm.cpp

@@ -195,7 +195,7 @@ void remove_asmt::process_instruction(
       {
         gcc_asm_function_call("__asm_"+id2string(command), code, tmp_dest);
       }
-      else if(command=="sync") // Power
+      else if(command == ID_sync) // Power
       {
         goto_programt::targett t=tmp_dest.add_instruction(OTHER);
         t->source_location=code.source_location();
@@ -210,7 +210,7 @@ void remove_asmt::process_instruction(
         t->code.set(ID_RRcumul, true);
         t->code.set(ID_WRcumul, true);
       }
-      else if(command=="lwsync") // Power
+      else if(command == ID_lwsync) // Power
       {
         goto_programt::targett t=tmp_dest.add_instruction(OTHER);
         t->source_location=code.source_location();
@@ -223,7 +223,7 @@ void remove_asmt::process_instruction(
         t->code.set(ID_RWcumul, true);
         t->code.set(ID_RRcumul, true);
       }
-      else if(command=="isync") // Power
+      else if(command == ID_isync) // Power
       {
         goto_programt::targett t=tmp_dest.add_instruction(OTHER);
         t->source_location=code.source_location();

src/goto-symex/slice_by_trace.cpp

@@ -244,7 +244,7 @@ void symex_slice_by_tracet::compute_ts_back(
        !i->io_args.empty() &&
        i->io_args.front().id()=="trace_event")
     {
-      irep_idt event=i->io_args.front().get("event");
+      irep_idt event = i->io_args.front().get(ID_event);
 
       if(!alphabet.empty())
       {

src/solvers/smt2/smt2_parser.cpp

@@ -774,7 +774,7 @@ exprt smt2_parsert::function_application()
         }
         else if(id=="rotate_left" ||
                 id=="rotate_right" ||
-                id=="repeat" ||
+                id == ID_repeat ||
                 id=="sign_extend" ||
                 id=="zero_extend")
         {
@@ -826,7 +826,7 @@ exprt smt2_parsert::function_application()
 
             return typecast_exprt(op[0], unsigned_type);
           }
-          else if(id=="repeat")
+          else if(id == ID_repeat)
           {
             return nil_exprt();
           }

src/util/irep_ids.cpp

@@ -27,6 +27,14 @@ const char *irep_ids_table[]=
 
 #ifdef USE_DSTRING
 
+enum class idt:unsigned
+{
+#define IREP_ID_ONE(the_id) id_##the_id,
+#define IREP_ID_TWO(the_id, str) id_##the_id,
+
+#include "irep_ids.def" // NOLINT(build/include)
+};
+
 #define IREP_ID_ONE(the_id)                                                    \
   const dstringt ID_##the_id=dstringt::make_from_table_index(                  \
       static_cast<unsigned>(idt::id_##the_id));