--- /dev/null
+#ifndef lint
+static char rcsid[] = "$Header$";
+#endif
+
+/*
+ * Memory manager. Memory is divided into NMEMS pieces. There is a struct
+ * for each piece telling where it is, how many bytes are used, and how may
+ * are left. If a request for core doesn't fit in the left bytes, an sbrk()
+ * is done and pieces after the one that requested the growth are moved up.
+ */
+
+#include <stdio.h>
+#include "out.h"
+#include "const.h"
+#include "assert.h"
+#include "debug.h"
+#include "memory.h"
+
+struct memory mems[NMEMS];
+
+bool incore = TRUE; /* TRUE while everything can be kept in core. */
+off_t core_position = (off_t)0; /* Index of current module. */
+
+#define AT_LEAST 2 /* See comment about string areas. */
+
+/*
+ * Initialize some pieces of core. We hope that this will be our last
+ * real allocation, meaning we've made the right choices.
+ */
+init_core()
+{
+ FILE *ledrc;
+ int piece;
+ off_t left;
+ register char *base;
+ register off_t total_size;
+ register struct memory *mem;
+ extern char *sbrk();
+
+#ifndef TJALK
+ /*
+ * Read in what should be allocated for each piece initially.
+ * This facilitates testing, but is slower and should not
+ * be done in the final version. XXX
+ */
+ incore = (ledrc = fopen(".ledrc", "r")) != (FILE *)0;
+
+ if (incore) {
+ while (fscanf(ledrc, "%d %d", &piece, &left) == 2)
+ mems[piece].mem_left = left;
+ fclose(ledrc);
+ }
+#else TJALK
+ mems[ALLOHEAD].mem_left = 20; /*XXX*/
+ mems[ALLOSECT].mem_left = 60; /*XXX*/
+ mems[ALLOEMIT + 0].mem_left = 65536;
+ mems[ALLOEMIT + 1].mem_left = 65536;
+ mems[ALLORELO].mem_left = 65536;
+ mems[ALLOLOCL].mem_left = 65536;
+ mems[ALLOGLOB].mem_left = 65536;
+ mems[ALLOLCHR].mem_left = 65536;
+ mems[ALLOGCHR].mem_left = 65536;
+#ifdef SYMDBUG
+ mems[ALLODBUG].mem_left = 65536;
+#endif SYMDBUG
+ mems[ALLOSYMB].mem_left = 4096;
+ mems[ALLOARCH].mem_left = 512;
+ mems[ALLOMODL].mem_left = 196608;
+ mems[ALLORANL].mem_left = 4096;
+#endif TJALK
+
+ total_size = (off_t)0;/* Will accumulate the sizes. */
+ base = sbrk(0); /* First free. */
+ for (mem = mems; mem < &mems[NMEMS]; mem++) {
+ mem->mem_base = base;
+ mem->mem_full = (off_t)0;
+ base += mem->mem_left; /* Each piece will start after prev. */
+ total_size += mem->mem_left;
+ }
+ /*
+ * String areas are special-cased. The first byte is unused as a way to
+ * distinguish a name without string from a name which has the first
+ * string in the string area.
+ */
+ if (mems[ALLOLCHR].mem_left == 0)
+ total_size += 1;
+ else
+ mems[ALLOLCHR].mem_left -= 1;
+ if (mems[ALLOGCHR].mem_left == 0)
+ total_size += 1;
+ else
+ mems[ALLOGCHR].mem_left -= 1;
+ mems[ALLOLCHR].mem_full = 1;
+ mems[ALLOGCHR].mem_full = 1;
+
+ if ((int)sbrk(total_size) == -1) {
+ incore = FALSE; /* In core strategy failed. */
+ if ((int)sbrk(AT_LEAST) == -1)
+ fatal("no core at all");
+ }
+
+}
+
+/*
+ * Allocate an extra block of `incr' bytes and move all pieces with index
+ * higher than `piece' up with the size of the block. Return whether the
+ * allocate succeeded.
+ */
+static bool
+move_up(piece, incr)
+ register int piece;
+ register off_t incr;
+{
+ register struct memory *mem;
+ extern char *sbrk();
+
+ debug("move_up(%d, %d)\n", piece, (int)incr, 0, 0);
+ if ((int)sbrk(incr) == -1)
+ return FALSE;
+
+ for (mem = &mems[NMEMS - 1]; mem > &mems[piece]; mem--)
+ copy_up(mem, incr);
+
+ mems[piece].mem_left += incr;
+ return TRUE;
+}
+
+extern int passnumber;
+
+/*
+ * This routine is called if `piece' needs `incr' bytes and the system won't
+ * give them. We first steal the free bytes of all lower pieces and move them
+ * and `piece' down. If that doesn't give us enough bytes, we steal the free
+ * bytes of all higher pieces and move them up. We return whether we have
+ * enough bytes, the first or the second time.
+ */
+static bool
+compact(piece, incr)
+ register int piece;
+ register off_t incr;
+{
+ register off_t gain;
+ register struct memory *mem;
+
+ debug("compact(%d, %d)\n", piece, (int)incr, 0, 0);
+ gain = mems[0].mem_left;
+ mems[0].mem_left = (off_t)0;
+ for (mem = &mems[1]; mem <= &mems[piece]; mem++) {
+ /* Here memory is inserted before a piece. */
+ assert(passnumber == FIRST || gain == (off_t)0);
+ copy_down(mem, gain);
+ gain += mem->mem_left;
+ mem->mem_left = (off_t)0;
+ }
+ /*
+ * Note that we already added the left bytes of the piece we want to
+ * enlarge to `gain'.
+ */
+ if (gain < incr) {
+ register off_t up = (off_t)0;
+
+ for (mem = &mems[NMEMS - 1]; mem > &mems[piece]; mem--) {
+ /* Here memory is appended after a piece. */
+ up += mem->mem_left;
+ copy_up(mem, up);
+ mem->mem_left = (off_t)0;
+ }
+ gain += up;
+ }
+ mems[piece].mem_left = gain;
+ return gain >= incr;
+}
+
+/*
+ * The bytes of `mem' must be moved `dist' down in the address space.
+ * We copy the bytes from low to high, because the tail of the new area may
+ * overlap with the old area, but we do not want to overwrite them before they
+ * are copied.
+ */
+static
+copy_down(mem, dist)
+ register struct memory *mem;
+ off_t dist;
+{
+ register char *old;
+ register char *new;
+ register off_t size;
+
+ size = mem->mem_full;
+ old = mem->mem_base;
+ new = old - dist;
+ mem->mem_base = new;
+ while (size--)
+ *new++ = *old++;
+}
+
+/*
+ * The bytes of `mem' must be moved `dist' up in the address space.
+ * We copy the bytes from high to low, because the tail of the new area may
+ * overlap with the old area, but we do not want to overwrite them before they
+ * are copied.
+ */
+static
+copy_up(mem, dist)
+ register struct memory *mem;
+ off_t dist;
+{
+ register char *old;
+ register char *new;
+ register off_t size;
+
+ size = mem->mem_full;
+ old = mem->mem_base + size;
+ new = old + dist;
+ while (size--)
+ *--new = *--old;
+ mem->mem_base = new;
+}
+
+/*
+ * Add `size' bytes to the bytes already allocated for `piece'. If it has no
+ * free bytes left, ask them from memory or, if that fails, from the free
+ * bytes of other pieces. The offset of the new area is returned. No matter
+ * how many times the area is moved, because of another allocate, this offset
+ * remains valid.
+ */
+off_t
+alloc(piece, size)
+ register int piece;
+ register off_t size;
+{
+ register off_t incr = 0;
+ register off_t left = mems[piece].mem_left;
+ register off_t full = mems[piece].mem_full;
+
+ assert(passnumber == FIRST || (!incore && piece == ALLOMODL));
+ if (size == (off_t)0)
+ return full;
+
+ while (left + incr < size)
+ incr += INCRSIZE;
+
+ if (incr == 0 || move_up(piece, incr) || compact(piece, incr)) {
+ mems[piece].mem_full += size;
+ mems[piece].mem_left -= size;
+ return full;
+ } else {
+ incore = FALSE;
+ return BADOFF;
+ }
+}
+
+/*
+ * Same as alloc() but for a piece which really needs it. If the first
+ * attempt fails, release the space occupied by other pieces and try again.
+ */
+off_t
+hard_alloc(piece, size)
+ int piece;
+ off_t size;
+{
+ off_t ret;
+ register int i;
+
+ if ((ret = alloc(piece, size)) != BADOFF)
+ return ret;
+
+ /*
+ * Deallocate what we don't need.
+ */
+ for (i = 0; i < NMEMS; i++) {
+ switch (i) {
+ case ALLOHEAD:
+ case ALLOSECT:
+ case ALLOGLOB:
+ case ALLOGCHR:
+ case ALLOSYMB:
+ case ALLOARCH:
+ case ALLOMODL:
+ break; /* Do not try to deallocate this. */
+ default:
+ dealloc(i);
+ break;
+ }
+ }
+ free_saved_moduls();
+
+ return alloc(piece, size);
+}
+
+/*
+ * We don't need the previous modules, so we put the current module
+ * at the start of the piece allocated for module contents, thereby
+ * overwriting the saved modules, and release its space.
+ */
+static
+free_saved_moduls()
+{
+ register off_t size;
+ register char *old, *new;
+ register struct memory *mem = &mems[ALLOMODL];
+
+ size = mem->mem_full - core_position;
+ new = mem->mem_base;
+ old = new + core_position;
+ while (size--)
+ *new++ = *old++;
+ mem->mem_full -= core_position;
+ mem->mem_left += core_position;
+ core_position = (off_t)0;
+}
+
+/*
+ * The piece of memory with index `piece' is no longer needed.
+ * We take care that it can be used by compact() later, if needed.
+ */
+dealloc(piece)
+ register int piece;
+{
+ /*
+ * Some pieces need their memory throughout the program.
+ */
+ assert(piece != ALLOHEAD);
+ assert(piece != ALLOSECT);
+ assert(piece != ALLOGLOB);
+ assert(piece != ALLOGCHR);
+ assert(piece != ALLOSYMB);
+ assert(piece != ALLOARCH);
+ mems[piece].mem_left += mems[piece].mem_full;
+ mems[piece].mem_full = (off_t)0;
+}
+
+char *
+core_alloc(piece, size)
+ register int piece;
+ register off_t size;
+{
+ register off_t off;
+
+ if ((off = alloc(piece, size)) == BADOFF)
+ return (char *)0;
+ return address(piece, off);
+}
+
+/*
+ * Reset index into piece of memory for modules and
+ * take care that the allocated pieces will not be moved.
+ */
+freeze_core()
+{
+ register int i;
+
+ core_position = (off_t)0;
+
+ if (incore)
+ return;
+
+ for (i = 0; i < NMEMS; i++) {
+ switch (i) {
+ case ALLOHEAD:
+ case ALLOSECT:
+ case ALLOGLOB:
+ case ALLOGCHR:
+ case ALLOSYMB:
+ case ALLOARCH:
+ break; /* Do not try to deallocate this. */
+ default:
+ dealloc(i);
+ break;
+ }
+ }
+ compact(NMEMS - 1, (off_t)0);
+}
+
+/* ------------------------------------------------------------------------- */
+
+extern bool bytes_reversed;
+extern bool words_reversed;
+
+/*
+ * To transform the various pieces of the output in core to the file format,
+ * we must order the bytes in the ushorts and longs as ACK prescribes.
+ */
+write_bytes()
+{
+ register struct outhead *head;
+ ushort nsect, nrelo;
+ long offchar;
+ int fd;
+ register int piece;
+ extern ushort NLocals, NGlobals;
+ extern long NLChars, NGChars;
+ extern int flagword;
+ extern char *outputname;
+
+ head = (struct outhead *)mems[ALLOHEAD].mem_base;
+ nsect = head->oh_nsect;
+ nrelo = head->oh_nrelo;
+ offchar = OFF_CHAR(*head);
+
+ if (bytes_reversed || words_reversed) {
+ headswap();
+ sectswap(nsect);
+ reloswap(nrelo);
+ }
+ /*
+ * We allocated two areas: one for local and one for global names.
+ * Also, we used another kind of on_foff than on file.
+ * At the end of the global area we have put the section names.
+ */
+ if (!(flagword & SFLAG)) {
+ namecpy((struct outname *)mems[ALLOLOCL].mem_base,
+ NLocals,
+ offchar
+ );
+ namecpy((struct outname *)mems[ALLOGLOB].mem_base,
+ NGlobals + nsect,
+ offchar + NLChars
+ );
+ }
+ if ((fd = creat(outputname, 0666)) < 0)
+ fatal("can't create %s", outputname);
+ /*
+ * These pieces must always be written.
+ */
+ for (piece = ALLOHEAD; piece < ALLORELO; piece++)
+ writelong(fd, mems[piece].mem_base, mems[piece].mem_full);
+ /*
+ * The rest depends on the flags.
+ */
+ if (flagword & RFLAG)
+ writelong(fd, mems[ALLORELO].mem_base, mems[ALLORELO].mem_full);
+ if (!(flagword & SFLAG)) {
+ writelong(fd, mems[ALLOLOCL].mem_base, mems[ALLOLOCL].mem_full);
+ writelong(fd, mems[ALLOGLOB].mem_base, mems[ALLOGLOB].mem_full);
+ writelong(fd, mems[ALLOLCHR].mem_base + 1, NLChars);
+ writelong(fd, mems[ALLOGCHR].mem_base + 1, NGChars);
+#ifdef SYMDBUG
+ writelong(fd, mems[ALLODBUG].mem_base, mems[ALLODBUG].mem_size);
+#endif SYMDBUG
+ }
+ close(fd);
+}
+
+static
+writelong(fd, base, size)
+ register int fd;
+ register char *base;
+ register off_t size;
+{
+ register int chunk;
+
+ while (size) {
+ chunk = size > (off_t)MAXCHUNK ? MAXCHUNK : size;
+ write(fd, base, chunk);
+ size -= chunk;
+ base += chunk;
+ }
+}
+
+static
+headswap()
+{
+ register struct outhead *head;
+
+ head = (struct outhead *)mems[ALLOHEAD].mem_base;
+ swap((char *)head, SF_HEAD);
+}
+
+static
+sectswap(nsect)
+ register ushort nsect;
+{
+ register struct outsect *sect;
+
+ sect = (struct outsect *)mems[ALLOSECT].mem_base;
+ while (nsect--)
+ swap((char *)sect++, SF_SECT);
+}
+
+static
+reloswap(nrelo)
+ register ushort nrelo;
+{
+ register struct outrelo *relo;
+
+ relo = (struct outrelo *)mems[ALLORELO].mem_base;
+ while (nrelo--)
+ swap((char *)relo++, SF_RELO);
+}
+
+static
+namecpy(name, nname, offchar)
+ register struct outname *name;
+ register ushort nname;
+ register long offchar;
+{
+ while (nname--) {
+ if (name->on_foff)
+ name->on_foff += offchar - 1;
+ if (bytes_reversed || words_reversed)
+ swap((char *)name, SF_NAME);
+ name++;
+ }
+}
public / ack.git / commitdiff