statement.c

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/*
 
  $Id: statement.c 23065 2016-03-02 09:05:50Z coelho $
 
  Copyright 1989-2016 MINES ParisTech
 
  This file is part of PIPS.
 
  PIPS is free software: you can redistribute it and/or modify it
  under the terms of the GNU General Public License as published by
  the Free Software Foundation, either version 3 of the License, or
  any later version.
 
  PIPS is distributed in the hope that it will be useful, but WITHOUT ANY
  WARRANTY; without even the implied warranty of MERCHANTABILITY or
  FITNESS FOR A PARTICULAR PURPOSE.
 
  See the GNU General Public License for more details.
 
  You should have received a copy of the GNU General Public License
  along with PIPS.  If not, see <http://www.gnu.org/licenses/>.
 
*/
#ifdef HAVE_CONFIG_H
    #include "pips_config.h"
#endif
 
/*******************  STATEMENTS *******************/
 
/* Attention, the null statement in C is represented as the continue
   statement in Fortran (make_continue_statement means make_null_statement)*/
 
// To have strndup(), asprintf()...:
#include <stdlib.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
 
#include "genC.h"
#include "linear.h"
#include "ri.h"
#include "ri-util.h"
#include "parser_private.h"
#include "c_syntax.h"
 
 
#include "resources.h"
#include "database.h"
 
#include "misc.h"
#include "text-util.h"
#include "prettyprint.h" // for fprint_expression in an error message
                         // and for words_expression() really used
                         // Maybe, the same stuff could be programmed otherwise
#include "properties.h"
#include "alias_private.h"
 
stack BlockStack; /* BlockStack is used to handle block scope */
 
list LabeledStatements; /* list of labeled statements of the current module*/
 
stack SwitchGotoStack = stack_undefined;
stack SwitchControllerStack = stack_undefined;
stack LoopStack = stack_undefined; /* is used for switch statements also, because we do not
                                        distinguish a break in a loop or a switch */
 
void MakeCurrentModule(entity e)
{
  /* This must be changed later, the storage is of type return and we
     have to create a new entity*/
  entity_storage(e) = make_storage_rom() /* make_storage_return(e) */;
  if (value_undefined_p(entity_initial(e)))
    entity_initial(e) = make_value(is_value_code,
                                   make_code(NIL,strdup(""),
                                             make_sequence(NIL),
                                             NIL,
                                             make_language_c()));
  /* code_declaration to be updated : only need formal parameters, because the others are added in
     block statement declaration ? */
  pips_debug(4,"Set current module entity %s\n",entity_user_name(e));
 
  /* The next two tests are replicated from the Fortran parser,
     Syntax/procedure.c, MakeCurrentFunction() */
 
  /* In case the module is parsed a second time, clean up the symbol
     table to avoid variable redefinition warnings and errors */
  if(!value_undefined_p(entity_initial(e))) {
    if(value_code_p(entity_initial(e))) {
      code c = value_code(entity_initial(e));
      if(!code_undefined_p(c) && !ENDP(code_declarations(c))) {
        /* Clean up existing local entities in case of a recompilation. */
        CCleanLocalEntities(e);
      }
    }
  }
 
  /* Let's hope cf is not an intrinsic: name conflict (the problem may
     have been detected earlier in UpdateEntity() if there are
     arguments) */
  if( entity_type(e) != type_undefined
      && intrinsic_entity_p(e) ) {
    pips_user_warning("Intrinsic %s redefined.\n"
                      "This is not supported by PIPS. Please rename %s\n",
                      entity_local_name(e), entity_local_name(e));
    /* Unfortunately, an intrinsics cannot be redefined, just like a user function
     * or subroutine after editing because intrinsics are not handled like
     * user functions or subroutines. They are not added to the called_modules
     * list of other modules, unless the redefining module is parsed FIRST.
     * There is not mechanism in PIPS to control the parsing order.
     */
    CParserError("Name conflict between a "
                 "function and an intrinsic\n");
  }
 
 
  set_current_module_entity(e);
  init_c_areas();
  init_c_implicit_variables(e);
  LabeledStatements = NIL;
  SwitchGotoStack = stack_make(sequence_domain,0,0);
  SwitchControllerStack = stack_make(expression_domain,0,0);
  LoopStack = stack_make(basic_domain,0,0);
}
 
void ResetCurrentModule()
{
  CModuleMemoryAllocation(get_current_module_entity());
  if (get_bool_property("PARSER_DUMP_SYMBOL_TABLE"))
    fprint_C_environment(stderr, get_current_module_entity());
  pips_debug(4,"Reset current module entity %s\n",get_current_module_name());
  reset_current_module_entity();
  stack_free(&SwitchGotoStack);
  stack_free(&SwitchControllerStack);
  stack_free(&LoopStack);
  stack_free(&BlockStack);
  /* Reset them to stack_undefined_p instead of STACK_NULL */
  SwitchGotoStack = stack_undefined;
  SwitchControllerStack = stack_undefined;
  LoopStack = stack_undefined;
  BlockStack = stack_undefined;
}
 
void InitializeBlock()
{
  BlockStack = stack_make(statement_domain,0,0);
}
 
/* Create a block statement
 
   It also gather all the declarations in the statements and declare them
   in the block sequence.
*/
statement MakeBlock(list stmts)
{
  /* To please to current RI choices about Fortran, blocks cannot carry
     line numbers nor comments */
  /* Anyway, it might be much too late to retrieve the comment
     associated to the beginning of the block. The lost comment
     appears after the last statement of the block. To save it, as is
     done in Fortran, an empty statement should be added at the end of
     the sequence. */
  // Gather all the direct declaration entities from the statements:
  list dl = statements_to_direct_declarations(stmts);
 
  statement s = make_statement(entity_empty_label(),
                               STATEMENT_NUMBER_UNDEFINED /* get_current_C_line_number() */,
                               STATEMENT_ORDERING_UNDEFINED,
                               empty_comments /* get_current_C_comment() */,
                               make_instruction_sequence(make_sequence(stmts)),
                               dl, string_undefined, empty_extensions (), make_synchronization_none());
 
  discard_C_comment();
 
  ifdebug(1) {
      fprintf(stderr, "Declaration list: ");
      if(ENDP(statement_declarations(s)))
        fprintf(stderr, "NONE\n");
      else {
        print_entities(statement_declarations(s));
        fprintf(stderr, "\n");
      }
    }
 
  pips_assert("Block statement is consistent",statement_consistent_p(s));
  return s;
}
 
 
statement FindStatementFromLabel(entity l)
{
  MAP(STATEMENT,s,
  {
    if (statement_label(s) == l)
      return s;
  },LabeledStatements);
  return statement_undefined;
}
 
 
/* Construct a new statement from \param s by adding a \param label and a
   \param comment. If it is possible to do it without creating a new
   statement, retun the old one modified according to.
*/
statement MakeLabeledStatement(string label, statement s, string comment) {
  entity l = MakeCLabel(label);
  statement labeled_statement;
  // Get the statement with the l label, if any:
  statement smt = FindStatementFromLabel(l);
  if (smt == statement_undefined) {
    /* There is no other statement already associated with this
       label... */
    /* Add a label and deal all the gory details about the PIPS internal
     representation: */
    s = add_label_to_statement(l, s, &labeled_statement);
    // Keep a track of this statement associated to a label:
    LabeledStatements = CONS(STATEMENT, labeled_statement, LabeledStatements);
  }
  else {
    /* There is already a statement stub smt associated to this label with
       some gotos pointing to it, so keep it as the labeled target. */
    if (!instruction_sequence_p(statement_instruction(s))
        && unlabelled_statement_p(s)) {
      /* The statement does not have a label and can accept one, so
         patch in place smt: */
      statement_instruction(smt) =  statement_instruction(s);
      statement_comments(smt) = statement_comments(s);
      // Discard the old statement:
      statement_instruction(s) = instruction_undefined;
      statement_comments(s) = string_undefined;
      free_statement(s);
      // And keep the old one:
      s = smt;
      labeled_statement = s;
    }
    else {
      /* The statement can not accept a label or another one, just keep
         the previous label in front: */
      list stmts = gen_statement_cons(s, NIL);
      stmts = gen_statement_cons(smt, stmts);
      statement seq = make_block_statement(stmts);
      labeled_statement = smt;
      s = seq;
    }
  }
  // Associate the current comment to the statement with the label:
  if (comment != string_undefined) {
    insert_comments_to_statement(labeled_statement, comment);
    free(comment);
  }
  return s;
}
 
 
statement MakeGotoStatement(string label)
{
  entity l = MakeCLabel(label);
  statement gts = statement_undefined;
 
  /* Find the corresponding statement from its label,
     if not found, create a pseudo one, which will be replaced lately when
     we see the statement (label: statement) */
 
  statement s = FindStatementFromLabel(l);
  if (s == statement_undefined) {
    s = make_continue_statement(l);
    LabeledStatements = CONS(STATEMENT,s,LabeledStatements);
  }
  gts = make_statement(entity_empty_label(),
                       get_current_C_line_number(),
                       STATEMENT_ORDERING_UNDEFINED,
                       get_current_C_comment(),
                       make_instruction(is_instruction_goto,s),NIL,NULL,
                       empty_extensions (), make_synchronization_none());
 
  return gts;
}
 
entity MakeCLabel(string s)
{
  string ename = strdup(concatenate(LABEL_PREFIX,s,NULL));
  entity l = FindOrCreateEntity(get_current_module_name(),ename);
  free(ename);
  if (entity_type(l) == type_undefined)
    {
      pips_debug(7,"Label %s\n", s);
      entity_type(l) = MakeTypeStatement();
      entity_storage(l) = make_storage_rom();
      entity_initial(l) = make_value(is_value_constant,
                                     make_constant_litteral());
    }
  else
    pips_debug(7, "Label %s already exists\n", s);
  return(l);
}
 
 
statement MakeWhileLoop(list lexp, statement s, bool before)
{
  statement smt;
  int i = basic_int((basic) stack_head(LoopStack));
  string lab1;
  asprintf(&lab1,"%s%s%d", get_label_prefix(), "loop_end_", i);
  statement s1 = FindStatementFromLabel(MakeCLabel(lab1));
  free(lab1);
  string lab2;
  asprintf(&lab2,"%s%s%d", get_label_prefix(), "break_", i);
  statement s2 = FindStatementFromLabel(MakeCLabel(lab2));
  free(lab2);
 
  if (!statement_undefined_p(s1))
    {
      /* This loop has a continue statement which has been transformed to goto
         Add the labeled statement at the end of loop body*/
      insert_statement(s,s1,false);
    }
 
  smt = make_whileloop_statement(MakeCommaExpression(lexp),
                                 s,
                                 get_current_C_line_number(),
                                 before);
  if (!statement_undefined_p(s2))
    {
      /* This loop has a break statement which has been transformed to goto
         Add the labeled statement after the loop */
      insert_statement(smt,s2,false);
    }
 
  pips_assert("While loop is consistent",statement_consistent_p(smt));
  /* ifdebug(5) */
  /*   { */
  /*     printf("While loop statement: \n"); */
  /*     print_statement(smt); */
  /*   } */
  return smt;
}
 
 
/* Create a for-loop statement with some parser-specific characteristics.
 
   A more generic implementation would have been in ri-util instead.
 
   There are assumptions that 2 comments have been pushed in the parser
   before.
 
   @param[in] e1 is the init part of the for
 
   @param[in] e2 is the conditional part of the for
 
   @param[in] e3 is the increment part of the for
 
   @param[in] body is the loop body statement
 
   @return a statement with the for
 
   Beware that a block is returned instead of a forloop when a break
   has been processed. The forloop is somewhere in there...
*/
statement MakeForloop(expression e1,
                      expression e2,
                      expression e3,
                      statement body) {
  forloop f;
  statement smt;
  // Assume this push have been done in the parser:
  int sn = pop_current_C_line_number();
  expression init = e1;
  expression cond = e2;
  expression inc = e3;
 
  pips_assert("For loop body consistent",statement_consistent_p(body));
 
  if(expression_undefined_p(init))
    init = make_call_expression(entity_intrinsic(CONTINUE_FUNCTION_NAME),
                                NIL);
  else
    simplify_C_expression(init);
 
  if(expression_undefined_p(cond))
    /* A bool C constant cannot be used
       because stdbool.h may not be
       included */
    /* cond = make_call_expression(MakeConstant(TRUE_OPERATOR_NAME, */
    /* is_basic_logical), */
    /* NIL); */
    cond = int_to_expression(1);
  else
    simplify_C_expression(cond);
 
  if(expression_undefined_p(inc))
    inc = make_call_expression(entity_intrinsic(CONTINUE_FUNCTION_NAME),
                               NIL);
  else
    simplify_C_expression(inc);
 
  int i = basic_int((basic) stack_head(LoopStack));
  /* Create some land-pad labels to deal with break and continue.
 
     Looks like some memory leaks if no break or continue...
 
     What happens if this label is already used by the programmer? If
     I increment i, the label may not be retrieved when
     needed... unless LoopStack is updated...
 */
  string lab1 = string_undefined;
  //do {
  //if(!string_undefined_p(lab1)) free(lab1);
  asprintf(&lab1, "%s%s%d", get_label_prefix(), "loop_end_", i);
    //i++;
    //} while(label_string_defined_in_current_module_p(lab1)()
  statement s1 = FindStatementFromLabel(MakeCLabel(lab1));
  free(lab1);
 
  string lab2 = string_undefined;
  //do {
  //if(!string_undefined_p(lab2)) free(lab2);
    asprintf(&lab2, "%s%s%d", get_label_prefix(), "break_", i);
    //i++;
    //} while(label_string_defined_in_current_module_p(lab1)()
  statement s2 = FindStatementFromLabel(MakeCLabel(lab2));
  free(lab2);
 
  if (!statement_undefined_p(s1))
    /* This loop has a continue statement which has been transformed to goto.
 
       Add the labeled statement at the end of loop body*/
    insert_statement(body, s1, false);
 
  /*  The for clause may contain declarations*/
  f = make_forloop(init, cond, inc, body);
  smt = make_statement(entity_empty_label(),
                       get_current_C_line_number(),
                       STATEMENT_ORDERING_UNDEFINED,
                       string_undefined,
                       make_instruction_forloop(f),
                       NIL, string_undefined,
                       empty_extensions(), make_synchronization_none());
 
  if (!statement_undefined_p(s2))
    /* This loop has a break statement which has been transformed to goto
       Add the labeled statement after the loop */
    insert_statement(smt, s2, false);
 
  // Assume these 2 push have been done in the parser:
  string comment_after_for_clause = pop_current_C_comment();
  string comment_before_for_clause = pop_current_C_comment();
  string sc = strdup(concatenate(comment_before_for_clause,
                                 comment_after_for_clause,
                                 NULL));
  free(comment_after_for_clause);
  free(comment_before_for_clause);
  smt = add_comment_and_line_number(smt, sc, sn);
  stack_pop(LoopStack);
  pips_assert("For loop consistent", statement_consistent_p(smt));
 
  pips_assert("For loop is consistent", forloop_consistent_p(f));
  /* ifdebug(5) { */
  /*   printf("For loop statement: \n"); */
  /*   print_statement(smt); */
  /* } */
  return smt;
}
 
/* Because a break in the forloop requires the generation of an extra
   label statement after the forloop. See MakeForLoop(). */
static forloop find_forloop_in_statement(statement s)
{
  forloop fl = forloop_undefined;
  if(statement_forloop_p(s))
    fl = statement_forloop(s);
  else if(statement_block_p(s)) {
    list sl = statement_block(s);
    statement fs = STATEMENT(CAR(CDR(sl)));
    if(statement_forloop_p(fs))
      fl = statement_forloop(fs);
  }
  if(forloop_undefined_p(fl))
    pips_internal_error("Unexpected forloop encoding\n");
  return fl;
}
 
/* Create a C99 for-loop statement with a declaration as first parameter
   in the for clause, with some parser-specific characteristics.
 
   To represent for(int i = a;...;...) we generate instead:
   {
     int i;
     for(int i = a;...;...)
   }
 
   The for could be generated back into the original form by the
   prettyprinter.  To differentiate between such a C99 for loop or a
   for-loop that was really written with the i declaration just before,
   west may mark the for loop with an extension here so that the
   prettyprinter could use this hint to know if it has to do some
   resugaring or not.
 
   @param[in,out] decls is the init part of the for. It is a declaration
   statement list
 
   @param[in] e2 is the conditional part of the for
 
   @param[in] e3 is the increment part of the for
 
   @param[in] body is the loop body statement
 
   @return a statement that contains the declaration and the for
*/
statement MakeForloopWithIndexDeclaration(list decls,
                                          expression e2,
                                          expression e3,
                                          statement body) {
  /* ifdebug(6) { */
  /*   printf("For loop statement declarations: \n"); */
  /*   print_statements(decls); */
  /* } */
  // FI: modified because insert_statement() should not be used with
  // declaration statements although it would be OK in this special case
  // statement decl = make_statement_from_statement_list_or_empty_block(decls);
  statement decl = make_block_statement(decls);
  /* First generate naive but more robust version in the RI, such as:
 
     {
       int i = a;
       for(;...;...)
     }
  */
  statement for_s = MakeForloop(expression_undefined, e2, e3, body);
  /* We inject the for in its declaration statement to have the naive
     representation: */
  // insert_statement(decl, for_s, false);
  append_statement_to_block_statement(decl, for_s);
  // Gather all the direct declarations from the statements in the block
  list dl = statements_to_direct_declarations(statement_block(decl));
  // to put them on the block statement:
  statement_declarations(decl) = dl;
 
  if (!get_bool_property("C_PARSER_GENERATE_NAIVE_C99_FOR_LOOP_DECLARATION")) {
    /* We try to refine to inject back an initialization in the for-clause.
 
       Note split_initializations_in_statemen() works only on a block */
    split_initializations_in_statement(decl);
    list l = statement_block(decl);
    size_t len = gen_length(l);
    ifdebug(6)
      printf("Number of statements in the block: %zd\n", len);
    if (len == 3) {
      /* We are interested in solving the simple case when there are 3
         statements because we should be in the form of:
         int i;
         i = a;
         for(;...;...)
      */
      // So we pick the initialization part which is the second statement:
      statement init = STATEMENT(gen_nth(1, l));
      // Remove it from the enclosing declaration statement:
      gen_remove(&l, init);
      // Get the assignment:
      call c = statement_call(init);
      // Housekeeping: first protect what we want to keep somewhere else...
      instruction_call(statement_instruction(init)) = call_undefined;
      // ... and free the now useless container:
      free_statement(init);
      // Make from it an expression that can appear inside the for clause:
      expression e = call_to_expression(c);
      // Get the for-loop:
      forloop f = find_forloop_in_statement(for_s);
      // Remove the default-generated initialization expression:
      free_expression(forloop_initialization(f));
      // Put the new one instead:
      forloop_initialization(f) = e;
      if (get_bool_property("C_PARSER_GENERATE_COMPACT_C99_FOR_LOOP_DECLARATION")) {
        /* We need to remove the decl block statement and move the index
           declaration directly in the for statement. */
 
        /* Not yet implemented because it needs to extend
           declaration_statement_p for any kind of loops, the loop
           restructurers... */
        ;
      }
    }
  }
  return decl;
}
 
 
statement MakeSwitchStatement(statement s)
{
  /* Transform a switch statement to if - else - goto. Example:
 
     switch (c) {
     case 1:
     s1;
     case 2:
     s2;
     default:
     sd;
     }
 
     if (c==1) goto switch_xxx_case_1;
     if (c==2) goto switch_xxx_case_2;
     goto switch_xxx_default;
     switch_xxx_case_1: ;
     s1;
     switch_xxx_case_2: ;
     s2;
     switch_xxx_default: ;
     sd;
 
     In si, we can have goto break_xxx; (which was a break)
 
     and break_xxx: ; is inserted at the end of the switch statement
 
     The statement s corresponds to the body
 
     switch_xxx_case_1: ;
     s1;
     switch_xxx_case_2: ;
     s2;
     switch_xxx_default: ;
     sd;
 
     we have to insert
 
     if (c==1) goto switch_xxx_case_1;
     if (c==2) goto switch_xxx_case_2;
     goto switch_xxx_default;
 
 
     before s and return the inserted statement.  */
  int i = basic_int((basic) stack_head(LoopStack));
  string lab ;
  asprintf(&lab, "%sbreak_%d", get_label_prefix(), i);
  statement smt = statement_undefined;
  statement seq = statement_undefined;
  sequence oseq = (sequence)stack_head(SwitchGotoStack);
  list tl = sequence_statements(oseq);
  list ct = list_undefined;
  list ntl = NIL;
  statement ds = statement_undefined;
 
  ifdebug(8) {
    pips_debug(8, "tl=%p\n", tl);
  }
 
  /* For the time being, the switch comment is lost. It should already
     be included in the argument,s  */
  /* pop_current_C_comment(); */
 
  /* Make sure the default case is the last one in the test sequence */
  for(ct=tl;!ENDP(ct); POP(ct)) {
    statement s = STATEMENT(CAR(ct));
 
    if(instruction_goto_p(statement_instruction(s))) {
      ds = s;
    }
    else {
      /* Keep the cases in the user order. Tobe checked at the
         pARSED_PRINTED_FILE level. */
      ntl = gen_nconc(ntl, CONS(STATEMENT,s,NIL));
      //ntl = CONS(STATEMENT,s,ntl);
    }
  }
  if(statement_undefined_p(ds)) {
    /* no default case, jump out of the switch control structure */
    ds = MakeBreakStatement(string_undefined /*strdup("")*/);
  }
  ntl = gen_nconc(ntl, CONS(STATEMENT,ds,NIL));
  gen_free_list(tl);
  sequence_statements(oseq)=NIL;
  free_sequence(oseq);
  seq = instruction_to_statement(make_instruction_sequence(make_sequence(ntl)));
  //seq = instruction_to_statement(make_instruction_sequence(make_sequence(tl)));
 
  insert_statement(s,seq,true);
 
  smt = FindStatementFromLabel(MakeCLabel(lab));
  free(lab);
  if (!statement_undefined_p(smt))
    {
      /* This switch has a break statement which has been transformed to goto
         Add the labeled statement after the switch */
      insert_statement(s,smt,false);
    }
  pips_assert("Switch is consistent",statement_consistent_p(s));
  /* ifdebug(5) */
  /*   { */
  /*     printf("Switch statement: \n"); */
  /*     print_statement(s); */
  /*   } */
  return s;
}
 
/* Transform
 *
 * case e:
 *
 * to
 *
 * switch_xxx_case_e: ;
 *
 * and generate
 *
 * if (c == e) goto switch_xxx_case_e
 *
 *  where c is retrieved from SwitchControllerStack
 *  xxx is unique from LoopStack
 *
 * Before the code can be generated, expression e must be statically
 * evaluated, transformer into a character string, and this character
 * string must be made compatible with C constraints for labels.
 */
statement MakeCaseStatement(expression e)
{
  int i = basic_int((basic) stack_head(LoopStack));
  string lab = NULL;
  /* It might be easier to evaluate e since e must be evaluable at
     compile time... And it is necessary if e contains operators whose
     name cannot be part of a label: see switch04 */
  string estr = string_undefined;
  expression ne = e;
 
  /* We chose to ignore the impact of casts */
  if(expression_cast_p(e)) {
    cast c = expression_cast(e);
    ne = cast_expression(c);
  }
 
  if(expression_constant_p(ne)) {
    estr = expression_to_string(ne);
  }
  else {
    /* You must evaluate the constant expression. Hopefully it is an
       integer expression... */
    intptr_t val;
    if(expression_integer_value(ne, &val)) {
      asprintf(&estr, "%lld", (long long int) val);
    }
    else {
      set_prettyprint_language_tag(is_language_c);
      c_parser_user_warning("Expression \"%s\" not supported as case expression.\n",
                            expression_to_string(ne));
      CParserError("Unsupported case expression\n");
    }
  }
 
  string restr = estr;
 
  /* The expression may be a character */
  if(*estr=='\'') {
    /* remove the quotes */
    restr++;
    *(estr+strlen(estr)-1) = '\000';
  }
 
  /* Make sure "restr" only contains C characters valid for a label if
     a character constant is used: is_letter || is_digit || '_'. */
  if(strspn(restr,
      "ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789_abcdefghijklmnopqrstuvwxyz")!=strlen(restr) && *estr=='\'') {
    /* illegal characters such as '?' or ',' or '.' must be converted
       as well as octal constant such as '\001' and special
       characters such as '\n' */
    if(strlen(restr)==1) {
      /* Must be an illegal character for a label */
      /* FI: not too safe to make it octal among decimal because it
         can generate a label conflict. */
      asprintf(&lab,"%sswitch_%d_case_%hhd",get_label_prefix(),i,*restr);
    }
    else if(*restr=='\\') {
      if(*(restr+1)=='0'||*(restr+1)=='1'||*(restr+1)=='2'||*(restr+1)=='3')
        /* octal character */
        asprintf(&lab,"%sswitch_%d_case_o%s",get_label_prefix(),i,restr+1);
      else if(*(restr+1)=='x'||*(restr+1)=='u'||*(restr+1)=='U')
        /* hexadecimal character, unicode character */
        asprintf(&lab,"%sswitch_%d_case_%s",get_label_prefix(),i,restr+1);
      else {
        /* FI: let's deal with special cases such as \n, \r, \t,...
         * The initialization to zero is meaningless but avoids a warning.
         */
        char labc = 0; // A string would carry more ASCII information
        if(*(restr+1)=='a') // bell
          labc = '\a'; // "BEL"
        else if(*(restr+1)=='b') // backspace
          labc = '\b'; // "BS"
        else if(*(restr+1)=='f') // form feed
          labc = '\f'; // "FF"
        else if(*(restr+1)=='n') // new line
          labc = '\n'; // "LF"
        else if(*(restr+1)=='t') // horizontal tab
          labc = '\t'; // "HT"
        else if(*(restr+1)=='r') // carriage return
          labc = '\r'; // "CR"
        else if(*(restr+1)=='v') // vertical tab
          labc = '\v'; // "VT"
        else if(*(restr+1)=='\'') // quote
          labc = '\''; //
        else if(*(restr+1)=='\"') // double quote
          labc = '\"'; //
        else if(*(restr+1)=='\\') // backslash
          labc = '\\'; //
        else if(*(restr+1)=='\?') // question mark
          labc = '\?'; //
        else
          pips_internal_error("Unexpected case. %s\n", (restr));
        asprintf(&lab,"%sswitch_%d_case_%hhd",get_label_prefix(),i,labc);
      }
    }
  }
  else
    asprintf(&lab,"%sswitch_%d_case_%s",get_label_prefix(),i,restr);
 
  free(estr);
 
  statement s = MakeLabeledStatement(lab,
      make_continue_statement(entity_empty_label()),
      get_current_C_comment());
  expression cond = call_to_expression(make_call(entity_intrinsic("=="),
      CONS(EXPRESSION, stack_head(SwitchControllerStack),
          CONS(EXPRESSION, e, NIL))));
  test t = make_test(cond,MakeGotoStatement(lab),make_continue_statement(entity_undefined));
  sequence CurrentSwitchGotoStack = stack_head(SwitchGotoStack);
  sequence_statements(CurrentSwitchGotoStack) = gen_nconc(sequence_statements(CurrentSwitchGotoStack),
      CONS(STATEMENT,test_to_statement(t),NULL));
 
  return s;
}
 
statement MakeDefaultStatement()
{
  /* Return the labeled statement
       switch_xxx_default: ;
     and add
       goto switch_xxx_default;
     to the switch header */
  int i = basic_int((basic) stack_head(LoopStack));
  string lab;
  asprintf(&lab,"%sswitch_%d_default", get_label_prefix(), i);
  statement s = MakeLabeledStatement(lab,
                                     make_continue_statement(entity_empty_label()),
                                     get_current_C_comment());
  sequence CurrentSwitchGoto = stack_head(SwitchGotoStack);
  /* If the default case is not last, it must be moved later in the
     sequence_statements(CurrentSwitchGoto) */
  sequence_statements(CurrentSwitchGoto) = gen_nconc(sequence_statements(CurrentSwitchGoto),
                                                               CONS(STATEMENT,MakeGotoStatement(lab),NULL));
  free(lab);
  return s;
}
 
statement MakeBreakStatement(string cmt)
{
  /* NN : I did not add a bool variable to distinguish between loop
     and switch statements :-( FI: Also, there is no protection in case
     the same label has been used by the programmer... */
  int i = basic_int((basic) stack_head(LoopStack));
  string lab;
  asprintf(&lab,"%sbreak_%d", get_label_prefix(), i);
  statement bs = MakeGotoStatement(lab);
  free(lab);
 
  statement_comments(bs) = cmt;
 
  return bs;
}
 
statement MakeContinueStatement(string cmt)
{
  /* Unique label with the LoopStack */
  int i = basic_int((basic) stack_head(LoopStack));
  string lab;
  asprintf(&lab, "%sloop_end_%d", get_label_prefix(), i);
  statement cs = MakeGotoStatement(lab);
  free(lab);
 
  statement_comments(cs) = cmt;
 
  return cs;
}
 
/* e is now owned by returned statement */
statement ExpressionToStatement(expression e)
{
  syntax s = expression_syntax(e);
  statement st = statement_undefined;
  string c = get_current_C_comment();
 
  if (syntax_call_p(s)) {
    st = call_to_statement(syntax_call(s));
    syntax_call(s)=call_undefined;
    free_expression(e);
  }
  else
    st = instruction_to_statement(make_instruction_expression(e));
 
  statement_number(st) = get_current_C_line_number();
  if(!string_undefined_p(c)) {
    statement_comments(st) = c;
  }
 
  return st;
}
 
/* The control list is hidden as arguments to the call to CONTROL in
 * the declaration statement s.
 *
 * It is made of 0 and 1 constant expressions.
 *
 * The first element tells the prettyprinter if the "extern" keyword
 * must be printed out.
 *
 * The next expressions tells the prettyprinter which variables should
 * be initialized by this statement.
 *
 * The control list for the initializations is built by the C parser, cyacc.y.
 *
 * This is only useful for global variables which can be declared
 * multiple times in multiple files and in multiple ways. See
 * Prettyprint/double_declaration01-14.c.
 */
list add_prettyprint_control_list_to_declaration_statement
(statement s, list initialization_expressions)
{
  list dl = statement_declarations(s); // declaration list
 
  if(ENDP(dl)) {
    if(ENDP(initialization_expressions)) {
      // FI: Well, the parser has declared fields for instance...
      return NIL;
    }
    else {
      pips_internal_error("Not expected\n");
      return initialization_expressions;
    }
  }
  else {
    /* The parser generated the initialization control list backwards */
    list iel = gen_nreverse(initialization_expressions);
 
    int dn = (int) gen_length(dl); // declaration number
    int in = (int) gen_length(iel); // initialization number
    entity first = ENTITY(CAR(dl));
 
    list niel = NIL;
 
    /* Try to patch the initialization list for derived entities
     * assuming that derived entities are located anywhere in the
     * declaration list. See decl64-65 and struct14-15.c
     */
 
    if(dn<in) {
      /* Place holder variables have been removed. Even if a
       * compilation unit is being parsed, initialization_expressions
       * should have no impact.
       */
      list ciel = iel;
      int i;
      for(i=0;i<dn-1;i++) {
        ciel = CDR(ciel);
      }
      list liel = CDR(ciel);
      CDR(ciel) = NIL;
      gen_full_free_list(liel);
      niel = iel;
      pips_assert("Same number of elements in both lists",
                  (int) gen_length(niel)==dn);
    }
    else if(dn>in) {
      list ciel = iel;
      FOREACH(ENTITY, e, dl) {
        // FI: we could instead check variable_entity_p()?
        if(derived_entity_p(e) || typedef_entity_p(e)) {
          niel = CONS(EXPRESSION, int_to_expression(0), niel);
          in++;
        }
        else {
          niel = CONS(EXPRESSION, EXPRESSION(CAR(ciel)), niel);
          POP(ciel);
        }
      }
      niel = gen_nreverse(niel);
      gen_free_list(iel); // initialization_expressions is dead
    }
    else {
      /* The initialization list is OK */
      niel = iel;
    }
 
 
    /* We could assert here than in = dn, but this is asserted below
     * with more explanations. However, only in debug mode 8. */
 
    /* Preserve the "extern" information right away before the C parser
       updates it each time it encounters a global declaration. */
 
    /* An extern declaration? */
 
    bool is_extern_statement_p = extern_prettyprint_control_list_p();
    bool is_dummy_statement_p = dummy_prettyprint_control_list_p();
    expression extern_declaration_p =
      int_to_expression((is_extern_statement_p? 1 : 0) +
                        (is_dummy_statement_p? 2 : 0));
 
    /* Provide debugging information */
 
    ifdebug(8) {
      fprintf(stderr, "Variable \"%s\" is %sdeclared EXTERN.\n", entity_user_name(first), is_extern_statement_p? "" : "not ");
      fprintf(stderr, "Number of declared variables: %d\n", dn);
      print_entities(dl);
      fprintf(stderr, "Number of initialization expressions: %d\n", in);
 
      // For debugging
      extern void print_expressions(list);
      print_expressions(niel);
      //printf("\nis_external = %s\n", bool_to_string(is_external));
    }
 
    /* Build the prettyprint control list: extern first and the initializations */
    list cel = CONS(EXPRESSION, extern_declaration_p, niel); // control expression list
 
    ifdebug(8) {
      fprintf(stderr, "Number of control expressions: %d\n", (int) gen_length(cel));
      print_expressions(cel);
      if(gen_length(dl)!=gen_length(niel)) {
        print_entities(dl);
        pips_assert("The number of variables declared is equal to the number of expressions", gen_length(dl)==gen_length(niel));
      }
      fprintf(stderr, "**************************\n");
    }
 
    /* Update the declaration statement */
 
    add_initialization_information_to_declaration_statement(s, cel);
 
    // reset the initialization_expressions list in the caller
    // initialization_expressions = NIL;
    return NIL;
  }
}
 
/* Force declaration statement s to be an extern declaration */
static bool extern_declaration_p = false;
 
void set_prettyprint_control_list_to_extern(void)
{
  extern_declaration_p = true;
}
 
/* void reset_prettyprint_control_list_to_extern(void) */
/* { */
/*   extern_declaration_p = false; */
/* } */
 
/* Provide the information only once */
bool extern_prettyprint_control_list_p(void)
{
  bool b = extern_declaration_p;
  extern_declaration_p = false;
  return b;
}
 
/* void set_prettyprint_control_list_to_extern(statement s) */
/* { */
/*   // pips_assert("s is a declaration statement", declaration_statement_p(s)); */
/*   call c = statement_call(s); */
/*   list cel = call_arguments(c); */
/*   if(ENDP(cel)) { */
/*     cel = CONS(EXPRESSION, int_to_expression(1), NIL); */
/*   } */
/*   else { */
/*     expression ce = EXPRESSION(CAR(cel)); */
/*     int extern_p = integer_constant_expression_value(ce); */
/*     if(!extern_p) { */
/*       EXPRESSION_(CAR(cel)) = int_to_expression(1); */
/*       free_expression(ce); */
/*     } */
/*   } */
/*   call_arguments(c) = cel; */
/* } */
␌
/* Force declaration statement s to be a dummy derived entity
 * declaration such as struct s;
 */
static bool dummy_declaration_p = false;
 
void set_prettyprint_control_list_to_dummy(void)
{
  dummy_declaration_p = true;
}
 
/* Provide the information only once */
bool dummy_prettyprint_control_list_p(void)
{
  bool b = dummy_declaration_p;
  dummy_declaration_p = false;
  return b;
}