Subversion Repositories open8_urisc

#include <ctype.h>

#include <stdio.h>

#include <stdlib.h>

#include <string.h>

#include "defines.h"

#include "discard.h"

#include "files.h"

#include "write.h"

extern struct reference *reference_first, *reference_last;

extern struct section *sec_first, *sec_last;

extern struct label *labels_first, *labels_last;

extern struct stack *stacks_first, *stacks_last;

int discard_unused_sections(void) {

  struct section *s;

  int a = 0, b = -1;

  /* iterate section discarding until there's no change in the

     amount of dropped sections */

  while (a != b) {

    s = sec_first;

    while (s != NULL) {

      s->referenced = 0;

      s = s->next;

    }

    a = b;

    discard_iteration();

    b = 0;

    s = sec_first;

    while (s != NULL) {

      if (s->referenced == 0)

        s->alive = NO;

      else

        s->alive = YES;

      if (s->alive == NO)

        b++;

      s = s->next;

    }

  }

  /* announce all the unreferenced sections that will get dropped */

  s = sec_first;

  while (s != NULL) {

    if (s->alive == NO)

      fprintf(stderr, "DISCARD: %s:%s: Section \"%s\" was discarded.\n",

              get_file_name(s->file_id), get_source_file_name(s->file_id, s->file_id_source), s->name);

    s = s->next;

  }

  return SUCCEEDED;

}

int discard_iteration(void) {

  struct reference *r;

  struct stackitem *si;

  struct section *s, *se;

  struct label *l;

  struct stack *st;

  int g;

  /* check section names for special characters '!', and

     check if the section is of proper type */

  s = sec_first;

  while (s != NULL) {

    if (s->name[0] == '!' || !(s->status == SECTION_STATUS_FREE || s->status == SECTION_STATUS_SEMIFREE)) {

      s->referenced++;

      s->alive = YES;

    }

    s = s->next;

  }

  /* loop through references */

  r = reference_first;

  while (r != NULL) {

    /* references to local labels don't count */

    if (r->name[0] == '_' || is_label_anonymous(r->name) == SUCCEEDED) {

      r = r->next;

      continue;

    }

    l = labels_first;

    while (l != NULL) {

      if (strcmp(l->name, r->name) == 0)

        break;

      l = l->next;

    }

    if (l != NULL && l->section_status == ON) {

      s = sec_first;

      while (s->id != l->section)

        s = s->next;

      if (s == NULL)

        fprintf(stderr, "DISCARD_ITERATION: Internal error!\n");

      if (r->section_status == OFF)

        s->referenced++;

      else if (r->section != s->id) {

        se = sec_first;

        while (se->id != r->section)

          se = se->next;

        if (se->alive == YES)

          s->referenced++;

      }

    }

    r = r->next;

  }

  /* loop through computations */

  st = stacks_first;

  while (st != NULL) {

    si = st->stack;

    g = 0;

    while (g != st->stacksize) {

      if (si->type == STACK_ITEM_TYPE_STRING && is_label_anonymous(si->string) == FAILED) {

        l = labels_first;

        while (l != NULL) {

          if (strcmp(l->name, si->string) == 0 && l->section_status == ON) {

            s = sec_first;

            while (s->id != l->section)

              s = s->next;

            if (st->section_status == OFF)

              s->referenced++;

            else if (st->section != s->id) {

              se = sec_first;

              while (se->id != st->section)

                se = se->next;

              if (se->alive == YES)

                s->referenced++;

            }

          }

          l = l->next;

        }

      }

      si++;

      g++;

    }

    st = st->next;

  }

  return SUCCEEDED;

}

/* drop labels that are inside discarded sections */

int discard_drop_labels(void) {

  struct label *l, *t;

  struct section *s;

  l = labels_first;

  while (l != NULL) {

    if (l->section_status == ON) {

      /* find the section */

      s = sec_first;

      while (s->id != l->section)

        s = s->next;

      /* is it dead? */

      if (s->alive == NO) {

        /* nope! remove the label! */

        if (l->prev == NULL)

          labels_first = l->next;

        else

          l->prev->next = l->next;

        if (l->next != NULL)

          l->next->prev = l->prev;

        t = l->next;

        free(l);

        l = t;

      }

      else

        l = l->next;

    }

    else

      l = l->next;

  }

  return SUCCEEDED;

}