0.8.16.23:
[sbcl.git] / src / runtime / gencgc.c
index b31bc72..c6009cc 100644 (file)
@@ -28,8 +28,8 @@
 #include <signal.h>
 #include <errno.h>
 #include <string.h>
-#include "runtime.h"
 #include "sbcl.h"
+#include "runtime.h"
 #include "os.h"
 #include "interr.h"
 #include "globals.h"
@@ -37,6 +37,7 @@
 #include "validate.h"
 #include "lispregs.h"
 #include "arch.h"
+#include "fixnump.h"
 #include "gc.h"
 #include "gc-internal.h"
 #include "thread.h"
@@ -49,8 +50,6 @@ void do_pending_interrupt(void);
 
 /* forward declarations */
 int gc_find_freeish_pages(int *restart_page_ptr, int nbytes, int unboxed);
-void  gc_set_region_empty(struct alloc_region *region);
-void gc_alloc_update_all_page_tables(void);
 static void  gencgc_pickup_dynamic(void);
 boolean interrupt_maybe_gc_int(int, siginfo_t *, void *);
 
@@ -69,7 +68,7 @@ boolean interrupt_maybe_gc_int(int, siginfo_t *, void *);
 boolean enable_page_protection = 1;
 
 /* Should we unmap a page and re-mmap it to have it zero filled? */
-#if defined(__FreeBSD__) || defined(__OpenBSD__)
+#if defined(__FreeBSD__) || defined(__OpenBSD__) || defined(__NetBSD__)
 /* comment from cmucl-2.4.8: This can waste a lot of swap on FreeBSD
  * so don't unmap there.
  *
@@ -94,7 +93,11 @@ unsigned large_object_size = 4 * PAGE_BYTES;
 
 /* the verbosity level. All non-error messages are disabled at level 0;
  * and only a few rare messages are printed at level 1. */
-unsigned gencgc_verbose = (QSHOW ? 1 : 0);
+#ifdef QSHOW
+unsigned gencgc_verbose = 1;
+#else
+unsigned gencgc_verbose = 0;
+#endif
 
 /* FIXME: At some point enable the various error-checking things below
  * and see what they say. */
@@ -274,7 +277,7 @@ count_write_protect_generation_pages(int generation)
     int count = 0;
 
     for (i = 0; i < last_free_page; i++)
-       if ((page_table[i].allocated != FREE_PAGE)
+       if ((page_table[i].allocated != FREE_PAGE_FLAG)
            && (page_table[i].gen == generation)
            && (page_table[i].write_protected == 1))
            count++;
@@ -295,7 +298,7 @@ count_generation_pages(int generation)
     return count;
 }
 
-/* Count the number of dont_move pages. */
+#ifdef QSHOW
 static int
 count_dont_move_pages(void)
 {
@@ -308,6 +311,7 @@ count_dont_move_pages(void)
     }
     return count;
 }
+#endif /* QSHOW */
 
 /* Work through the pages and add up the number of bytes used for the
  * given generation. */
@@ -372,7 +376,7 @@ print_generation_stats(int verbose) /* FIXME: should take FILE argument */
 
                /* Count the number of boxed pages within the given
                 * generation. */
-               if (page_table[j].allocated & BOXED_PAGE) {
+               if (page_table[j].allocated & BOXED_PAGE_FLAG) {
                    if (page_table[j].large_object)
                        large_boxed_cnt++;
                    else
@@ -381,7 +385,7 @@ print_generation_stats(int verbose) /* FIXME: should take FILE argument */
                if(page_table[j].dont_move) pinned_cnt++;
                /* Count the number of unboxed pages within the given
                 * generation. */
-               if (page_table[j].allocated & UNBOXED_PAGE) {
+               if (page_table[j].allocated & UNBOXED_PAGE_FLAG) {
                    if (page_table[j].large_object)
                        large_unboxed_cnt++;
                    else
@@ -533,35 +537,35 @@ gc_alloc_new_region(int nbytes, int unboxed, struct alloc_region *alloc_region)
     /* The first page may have already been in use. */
     if (page_table[first_page].bytes_used == 0) {
        if (unboxed)
-           page_table[first_page].allocated = UNBOXED_PAGE;
+           page_table[first_page].allocated = UNBOXED_PAGE_FLAG;
        else
-           page_table[first_page].allocated = BOXED_PAGE;
+           page_table[first_page].allocated = BOXED_PAGE_FLAG;
        page_table[first_page].gen = gc_alloc_generation;
        page_table[first_page].large_object = 0;
        page_table[first_page].first_object_offset = 0;
     }
 
     if (unboxed)
-       gc_assert(page_table[first_page].allocated == UNBOXED_PAGE);
+       gc_assert(page_table[first_page].allocated == UNBOXED_PAGE_FLAG);
     else
-       gc_assert(page_table[first_page].allocated == BOXED_PAGE);
-    page_table[first_page].allocated |= OPEN_REGION_PAGE; 
+       gc_assert(page_table[first_page].allocated == BOXED_PAGE_FLAG);
+    page_table[first_page].allocated |= OPEN_REGION_PAGE_FLAG; 
 
     gc_assert(page_table[first_page].gen == gc_alloc_generation);
     gc_assert(page_table[first_page].large_object == 0);
 
     for (i = first_page+1; i <= last_page; i++) {
        if (unboxed)
-           page_table[i].allocated = UNBOXED_PAGE;
+           page_table[i].allocated = UNBOXED_PAGE_FLAG;
        else
-           page_table[i].allocated = BOXED_PAGE;
+           page_table[i].allocated = BOXED_PAGE_FLAG;
        page_table[i].gen = gc_alloc_generation;
        page_table[i].large_object = 0;
        /* This may not be necessary for unboxed regions (think it was
         * broken before!) */
        page_table[i].first_object_offset =
            alloc_region->start_addr - page_address(i);
-       page_table[i].allocated |= OPEN_REGION_PAGE ;
+       page_table[i].allocated |= OPEN_REGION_PAGE_FLAG ;
     }
     /* Bump up last_free_page. */
     if (last_page+1 > last_free_page) {
@@ -722,12 +726,12 @@ gc_alloc_update_page_tables(int unboxed, struct alloc_region *alloc_region)
         * first_object_offset. */
        if (page_table[first_page].bytes_used == 0)
            gc_assert(page_table[first_page].first_object_offset == 0);
-       page_table[first_page].allocated &= ~(OPEN_REGION_PAGE);
+       page_table[first_page].allocated &= ~(OPEN_REGION_PAGE_FLAG);
 
        if (unboxed)
-           gc_assert(page_table[first_page].allocated == UNBOXED_PAGE);
+           gc_assert(page_table[first_page].allocated == UNBOXED_PAGE_FLAG);
        else
-           gc_assert(page_table[first_page].allocated == BOXED_PAGE);
+           gc_assert(page_table[first_page].allocated == BOXED_PAGE_FLAG);
        gc_assert(page_table[first_page].gen == gc_alloc_generation);
        gc_assert(page_table[first_page].large_object == 0);
 
@@ -748,11 +752,11 @@ gc_alloc_update_page_tables(int unboxed, struct alloc_region *alloc_region)
         * first_object_offset pointer to the start of the region, and set
         * the bytes_used. */
        while (more) {
-           page_table[next_page].allocated &= ~(OPEN_REGION_PAGE);
+           page_table[next_page].allocated &= ~(OPEN_REGION_PAGE_FLAG);
            if (unboxed)
-               gc_assert(page_table[next_page].allocated == UNBOXED_PAGE);
+               gc_assert(page_table[next_page].allocated==UNBOXED_PAGE_FLAG);
            else
-               gc_assert(page_table[next_page].allocated == BOXED_PAGE);
+               gc_assert(page_table[next_page].allocated == BOXED_PAGE_FLAG);
            gc_assert(page_table[next_page].bytes_used == 0);
            gc_assert(page_table[next_page].gen == gc_alloc_generation);
            gc_assert(page_table[next_page].large_object == 0);
@@ -800,15 +804,15 @@ gc_alloc_update_page_tables(int unboxed, struct alloc_region *alloc_region)
     } else {
        /* There are no bytes allocated. Unallocate the first_page if
         * there are 0 bytes_used. */
-       page_table[first_page].allocated &= ~(OPEN_REGION_PAGE);
+       page_table[first_page].allocated &= ~(OPEN_REGION_PAGE_FLAG);
        if (page_table[first_page].bytes_used == 0)
-           page_table[first_page].allocated = FREE_PAGE;
+           page_table[first_page].allocated = FREE_PAGE_FLAG;
     }
 
     /* Unallocate any unused pages. */
     while (next_page <= alloc_region->last_page) {
        gc_assert(page_table[next_page].bytes_used == 0);
-       page_table[next_page].allocated = FREE_PAGE;
+       page_table[next_page].allocated = FREE_PAGE_FLAG;
        next_page++;
     }
     release_spinlock(&free_pages_lock);
@@ -858,18 +862,18 @@ gc_alloc_large(int nbytes, int unboxed, struct alloc_region *alloc_region)
      * first_object_offset. */
     if (page_table[first_page].bytes_used == 0) {
        if (unboxed)
-           page_table[first_page].allocated = UNBOXED_PAGE;
+           page_table[first_page].allocated = UNBOXED_PAGE_FLAG;
        else
-           page_table[first_page].allocated = BOXED_PAGE;
+           page_table[first_page].allocated = BOXED_PAGE_FLAG;
        page_table[first_page].gen = gc_alloc_generation;
        page_table[first_page].first_object_offset = 0;
        page_table[first_page].large_object = 1;
     }
 
     if (unboxed)
-       gc_assert(page_table[first_page].allocated == UNBOXED_PAGE);
+       gc_assert(page_table[first_page].allocated == UNBOXED_PAGE_FLAG);
     else
-       gc_assert(page_table[first_page].allocated == BOXED_PAGE);
+       gc_assert(page_table[first_page].allocated == BOXED_PAGE_FLAG);
     gc_assert(page_table[first_page].gen == gc_alloc_generation);
     gc_assert(page_table[first_page].large_object == 1);
 
@@ -891,12 +895,12 @@ gc_alloc_large(int nbytes, int unboxed, struct alloc_region *alloc_region)
      * first_object_offset pointer to the start of the region, and
      * set the bytes_used. */
     while (more) {
-       gc_assert(page_table[next_page].allocated == FREE_PAGE);
+       gc_assert(page_table[next_page].allocated == FREE_PAGE_FLAG);
        gc_assert(page_table[next_page].bytes_used == 0);
        if (unboxed)
-           page_table[next_page].allocated = UNBOXED_PAGE;
+           page_table[next_page].allocated = UNBOXED_PAGE_FLAG;
        else
-           page_table[next_page].allocated = BOXED_PAGE;
+           page_table[next_page].allocated = BOXED_PAGE_FLAG;
        page_table[next_page].gen = gc_alloc_generation;
        page_table[next_page].large_object = 1;
 
@@ -956,14 +960,14 @@ gc_find_freeish_pages(int *restart_page_ptr, int nbytes, int unboxed)
        first_page = restart_page;
        if (large_p)            
            while ((first_page < NUM_PAGES)
-                  && (page_table[first_page].allocated != FREE_PAGE))
+                  && (page_table[first_page].allocated != FREE_PAGE_FLAG))
                first_page++;
        else
            while (first_page < NUM_PAGES) {
-               if(page_table[first_page].allocated == FREE_PAGE)
+               if(page_table[first_page].allocated == FREE_PAGE_FLAG)
                    break;
                if((page_table[first_page].allocated ==
-                   (unboxed ? UNBOXED_PAGE : BOXED_PAGE)) &&
+                   (unboxed ? UNBOXED_PAGE_FLAG : BOXED_PAGE_FLAG)) &&
                   (page_table[first_page].large_object == 0) &&
                   (page_table[first_page].gen == gc_alloc_generation) &&
                   (page_table[first_page].bytes_used < (PAGE_BYTES-32)) &&
@@ -990,7 +994,7 @@ gc_find_freeish_pages(int *restart_page_ptr, int nbytes, int unboxed)
        while (((bytes_found < nbytes) 
                || (!large_p && (num_pages < 2)))
               && (last_page < (NUM_PAGES-1))
-              && (page_table[last_page+1].allocated == FREE_PAGE)) {
+              && (page_table[last_page+1].allocated == FREE_PAGE_FLAG)) {
            last_page++;
            num_pages++;
            bytes_found += PAGE_BYTES;
@@ -1147,10 +1151,10 @@ copy_large_object(lispobj object, int nwords)
        gc_assert(page_table[first_page].first_object_offset == 0);
 
        next_page = first_page;
-       remaining_bytes = nwords*4;
+       remaining_bytes = nwords*N_WORD_BYTES;
        while (remaining_bytes > PAGE_BYTES) {
            gc_assert(page_table[next_page].gen == from_space);
-           gc_assert(page_table[next_page].allocated == BOXED_PAGE);
+           gc_assert(page_table[next_page].allocated == BOXED_PAGE_FLAG);
            gc_assert(page_table[next_page].large_object);
            gc_assert(page_table[next_page].first_object_offset==
                      -PAGE_BYTES*(next_page-first_page));
@@ -1175,7 +1179,7 @@ copy_large_object(lispobj object, int nwords)
        gc_assert(page_table[next_page].bytes_used >= remaining_bytes);
 
        page_table[next_page].gen = new_space;
-       gc_assert(page_table[next_page].allocated == BOXED_PAGE);
+       gc_assert(page_table[next_page].allocated == BOXED_PAGE_FLAG);
 
        /* Adjust the bytes_used. */
        old_bytes_used = page_table[next_page].bytes_used;
@@ -1187,7 +1191,7 @@ copy_large_object(lispobj object, int nwords)
        next_page++;
        while ((old_bytes_used == PAGE_BYTES) &&
               (page_table[next_page].gen == from_space) &&
-              (page_table[next_page].allocated == BOXED_PAGE) &&
+              (page_table[next_page].allocated == BOXED_PAGE_FLAG) &&
               page_table[next_page].large_object &&
               (page_table[next_page].first_object_offset ==
                -(next_page - first_page)*PAGE_BYTES)) {
@@ -1198,7 +1202,7 @@ copy_large_object(lispobj object, int nwords)
            gc_assert(page_table[next_page].write_protected == 0);
 
            old_bytes_used = page_table[next_page].bytes_used;
-           page_table[next_page].allocated = FREE_PAGE;
+           page_table[next_page].allocated = FREE_PAGE_FLAG;
            page_table[next_page].bytes_used = 0;
            bytes_freed += old_bytes_used;
            next_page++;
@@ -1209,7 +1213,7 @@ copy_large_object(lispobj object, int nwords)
        bytes_allocated -= bytes_freed;
 
        /* Add the region to the new_areas if requested. */
-       add_new_area(first_page,0,nwords*4);
+       add_new_area(first_page,0,nwords*N_WORD_BYTES);
 
        return(object);
     } else {
@@ -1217,9 +1221,9 @@ copy_large_object(lispobj object, int nwords)
        tag = lowtag_of(object);
 
        /* Allocate space. */
-       new = gc_quick_alloc_large(nwords*4);
+       new = gc_quick_alloc_large(nwords*N_WORD_BYTES);
 
-       memcpy(new,native_pointer(object),nwords*4);
+       memcpy(new,native_pointer(object),nwords*N_WORD_BYTES);
 
        /* Return Lisp pointer of new object. */
        return ((lispobj) new) | tag;
@@ -1241,9 +1245,9 @@ copy_unboxed_object(lispobj object, int nwords)
     tag = lowtag_of(object);
 
     /* Allocate space. */
-    new = gc_quick_alloc_unboxed(nwords*4);
+    new = gc_quick_alloc_unboxed(nwords*N_WORD_BYTES);
 
-    memcpy(new,native_pointer(object),nwords*4);
+    memcpy(new,native_pointer(object),nwords*N_WORD_BYTES);
 
     /* Return Lisp pointer of new object. */
     return ((lispobj) new) | tag;
@@ -1265,7 +1269,6 @@ copy_large_unboxed_object(lispobj object, int nwords)
 {
     int tag;
     lispobj *new;
-    lispobj *source, *dest;
     int first_page;
 
     gc_assert(is_lisp_pointer(object));
@@ -1273,7 +1276,7 @@ copy_large_unboxed_object(lispobj object, int nwords)
     gc_assert((nwords & 0x01) == 0);
 
     if ((nwords > 1024*1024) && gencgc_verbose)
-       FSHOW((stderr, "/copy_large_unboxed_object: %d bytes\n", nwords*4));
+       FSHOW((stderr, "/copy_large_unboxed_object: %d bytes\n", nwords*N_WORD_BYTES));
 
     /* Check whether it's a large object. */
     first_page = find_page_index((void *)object);
@@ -1291,18 +1294,18 @@ copy_large_unboxed_object(lispobj object, int nwords)
        gc_assert(page_table[first_page].first_object_offset == 0);
 
        next_page = first_page;
-       remaining_bytes = nwords*4;
+       remaining_bytes = nwords*N_WORD_BYTES;
        while (remaining_bytes > PAGE_BYTES) {
            gc_assert(page_table[next_page].gen == from_space);
-           gc_assert((page_table[next_page].allocated == UNBOXED_PAGE)
-                     || (page_table[next_page].allocated == BOXED_PAGE));
+           gc_assert((page_table[next_page].allocated == UNBOXED_PAGE_FLAG)
+                     || (page_table[next_page].allocated == BOXED_PAGE_FLAG));
            gc_assert(page_table[next_page].large_object);
            gc_assert(page_table[next_page].first_object_offset==
                      -PAGE_BYTES*(next_page-first_page));
            gc_assert(page_table[next_page].bytes_used == PAGE_BYTES);
 
            page_table[next_page].gen = new_space;
-           page_table[next_page].allocated = UNBOXED_PAGE;
+           page_table[next_page].allocated = UNBOXED_PAGE_FLAG;
            remaining_bytes -= PAGE_BYTES;
            next_page++;
        }
@@ -1314,7 +1317,7 @@ copy_large_unboxed_object(lispobj object, int nwords)
        gc_assert(page_table[next_page].bytes_used >= remaining_bytes);
 
        page_table[next_page].gen = new_space;
-       page_table[next_page].allocated = UNBOXED_PAGE;
+       page_table[next_page].allocated = UNBOXED_PAGE_FLAG;
 
        /* Adjust the bytes_used. */
        old_bytes_used = page_table[next_page].bytes_used;
@@ -1326,8 +1329,8 @@ copy_large_unboxed_object(lispobj object, int nwords)
        next_page++;
        while ((old_bytes_used == PAGE_BYTES) &&
               (page_table[next_page].gen == from_space) &&
-              ((page_table[next_page].allocated == UNBOXED_PAGE)
-               || (page_table[next_page].allocated == BOXED_PAGE)) &&
+              ((page_table[next_page].allocated == UNBOXED_PAGE_FLAG)
+               || (page_table[next_page].allocated == BOXED_PAGE_FLAG)) &&
               page_table[next_page].large_object &&
               (page_table[next_page].first_object_offset ==
                -(next_page - first_page)*PAGE_BYTES)) {
@@ -1338,7 +1341,7 @@ copy_large_unboxed_object(lispobj object, int nwords)
            gc_assert(page_table[next_page].write_protected == 0);
 
            old_bytes_used = page_table[next_page].bytes_used;
-           page_table[next_page].allocated = FREE_PAGE;
+           page_table[next_page].allocated = FREE_PAGE_FLAG;
            page_table[next_page].bytes_used = 0;
            bytes_freed += old_bytes_used;
            next_page++;
@@ -1349,8 +1352,8 @@ copy_large_unboxed_object(lispobj object, int nwords)
                   "/copy_large_unboxed bytes_freed=%d\n",
                   bytes_freed));
 
-       generations[from_space].bytes_allocated -= 4*nwords + bytes_freed;
-       generations[new_space].bytes_allocated += 4*nwords;
+       generations[from_space].bytes_allocated -= nwords*N_WORD_BYTES + bytes_freed;
+       generations[new_space].bytes_allocated += nwords*N_WORD_BYTES;
        bytes_allocated -= bytes_freed;
 
        return(object);
@@ -1360,19 +1363,10 @@ copy_large_unboxed_object(lispobj object, int nwords)
        tag = lowtag_of(object);
 
        /* Allocate space. */
-       new = gc_quick_alloc_large_unboxed(nwords*4);
-
-       dest = new;
-       source = (lispobj *) native_pointer(object);
-
-       /* Copy the object. */
-       while (nwords > 0) {
-           dest[0] = source[0];
-           dest[1] = source[1];
-           dest += 2;
-           source += 2;
-           nwords -= 2;
-       }
+       new = gc_quick_alloc_large_unboxed(nwords*N_WORD_BYTES);
+
+        /* Copy the object. */
+        memcpy(new,native_pointer(object),nwords*N_WORD_BYTES);
 
        /* Return Lisp pointer of new object. */
        return ((lispobj) new) | tag;
@@ -1416,10 +1410,10 @@ sniff_code_object(struct code *code, unsigned displacement)
     nheader_words = HeaderValue(*(lispobj *)code);
     nwords = ncode_words + nheader_words;
 
-    constants_start_addr = (void *)code + 5*4;
-    constants_end_addr = (void *)code + nheader_words*4;
-    code_start_addr = (void *)code + nheader_words*4;
-    code_end_addr = (void *)code + nwords*4;
+    constants_start_addr = (void *)code + 5*N_WORD_BYTES;
+    constants_end_addr = (void *)code + nheader_words*N_WORD_BYTES;
+    code_start_addr = (void *)code + nheader_words*N_WORD_BYTES;
+    code_end_addr = (void *)code + nwords*N_WORD_BYTES;
 
     /* Work through the unboxed code. */
     for (p = code_start_addr; p < code_end_addr; p++) {
@@ -1428,7 +1422,7 @@ sniff_code_object(struct code *code, unsigned displacement)
        unsigned d2 = *((unsigned char *)p - 2);
        unsigned d3 = *((unsigned char *)p - 3);
        unsigned d4 = *((unsigned char *)p - 4);
-#if QSHOW
+#ifdef QSHOW
        unsigned d5 = *((unsigned char *)p - 5);
        unsigned d6 = *((unsigned char *)p - 6);
 #endif
@@ -1586,10 +1580,10 @@ gencgc_apply_code_fixups(struct code *old_code, struct code *new_code)
     /* FSHOW((stderr,
             "/compiled code object at %x: header words = %d, code words = %d\n",
             new_code, nheader_words, ncode_words)); */
-    constants_start_addr = (void *)new_code + 5*4;
-    constants_end_addr = (void *)new_code + nheader_words*4;
-    code_start_addr = (void *)new_code + nheader_words*4;
-    code_end_addr = (void *)new_code + nwords*4;
+    constants_start_addr = (void *)new_code + 5*N_WORD_BYTES;
+    constants_end_addr = (void *)new_code + nheader_words*N_WORD_BYTES;
+    code_start_addr = (void *)new_code + nheader_words*N_WORD_BYTES;
+    code_end_addr = (void *)new_code + nwords*N_WORD_BYTES;
     /*
     FSHOW((stderr,
           "/const start = %x, end = %x\n",
@@ -1645,7 +1639,7 @@ gencgc_apply_code_fixups(struct code *old_code, struct code *new_code)
            /* If it's within the old_code object then it must be an
             * absolute fixup (relative ones are not saved) */
            if ((old_value >= (unsigned)old_code)
-               && (old_value < ((unsigned)old_code + nwords*4)))
+               && (old_value < ((unsigned)old_code + nwords*N_WORD_BYTES)))
                /* So add the dispacement. */
                *(unsigned *)((unsigned)code_start_addr + offset) =
                    old_value + displacement;
@@ -1950,74 +1944,47 @@ scav_weak_pointer(lispobj *where, lispobj object)
 }
 
 \f
-/* Scan an area looking for an object which encloses the given pointer.
- * Return the object start on success or NULL on failure. */
-static lispobj *
-search_space(lispobj *start, size_t words, lispobj *pointer)
-{
-    while (words > 0) {
-       size_t count = 1;
-       lispobj thing = *start;
-
-       /* If thing is an immediate then this is a cons. */
-       if (is_lisp_pointer(thing)
-           || ((thing & 3) == 0) /* fixnum */
-           || (widetag_of(thing) == BASE_CHAR_WIDETAG)
-           || (widetag_of(thing) == UNBOUND_MARKER_WIDETAG))
-           count = 2;
-       else
-           count = (sizetab[widetag_of(thing)])(start);
-
-       /* Check whether the pointer is within this object. */
-       if ((pointer >= start) && (pointer < (start+count))) {
-           /* found it! */
-           /*FSHOW((stderr,"/found %x in %x %x\n", pointer, start, thing));*/
-           return(start);
-       }
-
-       /* Round up the count. */
-       count = CEILING(count,2);
-
-       start += count;
-       words -= count;
-    }
-    return (NULL);
-}
-
-lispobj*
-search_read_only_space(lispobj *pointer)
+lispobj *
+search_read_only_space(void *pointer)
 {
-    lispobj* start = (lispobj*)READ_ONLY_SPACE_START;
-    lispobj* end = (lispobj*)SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0);
-    if ((pointer < start) || (pointer >= end))
+    lispobj *start = (lispobj *) READ_ONLY_SPACE_START;
+    lispobj *end = (lispobj *) SymbolValue(READ_ONLY_SPACE_FREE_POINTER,0);
+    if ((pointer < (void *)start) || (pointer >= (void *)end))
        return NULL;
-    return (search_space(start, (pointer+2)-start, pointer));
+    return (search_space(start, 
+                        (((lispobj *)pointer)+2)-start, 
+                        (lispobj *) pointer));
 }
 
 lispobj *
-search_static_space(lispobj *pointer)
+search_static_space(void *pointer)
 {
-    lispobj* start = (lispobj*)STATIC_SPACE_START;
-    lispobj* end = (lispobj*)SymbolValue(STATIC_SPACE_FREE_POINTER,0);
-    if ((pointer < start) || (pointer >= end))
+    lispobj *start = (lispobj *)STATIC_SPACE_START;
+    lispobj *end = (lispobj *)SymbolValue(STATIC_SPACE_FREE_POINTER,0);
+    if ((pointer < (void *)start) || (pointer >= (void *)end))
        return NULL;
-    return (search_space(start, (pointer+2)-start, pointer));
+    return (search_space(start, 
+                        (((lispobj *)pointer)+2)-start, 
+                        (lispobj *) pointer));
 }
 
 /* a faster version for searching the dynamic space. This will work even
  * if the object is in a current allocation region. */
 lispobj *
-search_dynamic_space(lispobj *pointer)
+search_dynamic_space(void *pointer)
 {
     int page_index = find_page_index(pointer);
     lispobj *start;
 
     /* The address may be invalid, so do some checks. */
-    if ((page_index == -1) || (page_table[page_index].allocated == FREE_PAGE))
+    if ((page_index == -1) ||
+       (page_table[page_index].allocated == FREE_PAGE_FLAG))
        return NULL;
     start = (lispobj *)((void *)page_address(page_index)
                        + page_table[page_index].first_object_offset);
-    return (search_space(start, (pointer+2)-start, pointer));
+    return (search_space(start, 
+                        (((lispobj *)pointer)+2)-start, 
+                        (lispobj *)pointer));
 }
 
 /* Is there any possibility that pointer is a valid Lisp object
@@ -2089,12 +2056,12 @@ possibly_valid_dynamic_space_pointer(lispobj *pointer)
        }
        /* Is it plausible cons? */
        if ((is_lisp_pointer(start_addr[0])
-           || ((start_addr[0] & 3) == 0) /* fixnum */
-           || (widetag_of(start_addr[0]) == BASE_CHAR_WIDETAG)
+           || (fixnump(start_addr[0]))
+           || (widetag_of(start_addr[0]) == CHARACTER_WIDETAG)
            || (widetag_of(start_addr[0]) == UNBOUND_MARKER_WIDETAG))
           && (is_lisp_pointer(start_addr[1])
-              || ((start_addr[1] & 3) == 0) /* fixnum */
-              || (widetag_of(start_addr[1]) == BASE_CHAR_WIDETAG)
+              || (fixnump(start_addr[1]))
+              || (widetag_of(start_addr[1]) == CHARACTER_WIDETAG)
               || (widetag_of(start_addr[1]) == UNBOUND_MARKER_WIDETAG)))
            break;
        else {
@@ -2140,7 +2107,7 @@ possibly_valid_dynamic_space_pointer(lispobj *pointer)
        }
        switch (widetag_of(start_addr[0])) {
        case UNBOUND_MARKER_WIDETAG:
-       case BASE_CHAR_WIDETAG:
+       case CHARACTER_WIDETAG:
            if (gencgc_verbose)
                FSHOW((stderr,
                       "*Wo3: %x %x %x\n",
@@ -2178,6 +2145,9 @@ possibly_valid_dynamic_space_pointer(lispobj *pointer)
 #endif
        case SIMPLE_ARRAY_WIDETAG:
        case COMPLEX_BASE_STRING_WIDETAG:
+#ifdef COMPLEX_CHARACTER_STRING_WIDETAG
+       case COMPLEX_CHARACTER_STRING_WIDETAG:
+#endif
        case COMPLEX_VECTOR_NIL_WIDETAG:
        case COMPLEX_BIT_VECTOR_WIDETAG:
        case COMPLEX_VECTOR_WIDETAG:
@@ -2193,6 +2163,9 @@ possibly_valid_dynamic_space_pointer(lispobj *pointer)
        case LONG_FLOAT_WIDETAG:
 #endif
        case SIMPLE_BASE_STRING_WIDETAG:
+#ifdef SIMPLE_CHARACTER_STRING_WIDETAG
+       case SIMPLE_CHARACTER_STRING_WIDETAG:
+#endif
        case SIMPLE_BIT_VECTOR_WIDETAG:
        case SIMPLE_ARRAY_NIL_WIDETAG:
        case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
@@ -2277,10 +2250,13 @@ maybe_adjust_large_object(lispobj *where)
     /* Check whether it's a vector or bignum object. */
     switch (widetag_of(where[0])) {
     case SIMPLE_VECTOR_WIDETAG:
-       boxed = BOXED_PAGE;
+       boxed = BOXED_PAGE_FLAG;
        break;
     case BIGNUM_WIDETAG:
     case SIMPLE_BASE_STRING_WIDETAG:
+#ifdef SIMPLE_CHARACTER_STRING_WIDETAG
+    case SIMPLE_CHARACTER_STRING_WIDETAG:
+#endif
     case SIMPLE_BIT_VECTOR_WIDETAG:
     case SIMPLE_ARRAY_NIL_WIDETAG:
     case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
@@ -2318,7 +2294,7 @@ maybe_adjust_large_object(lispobj *where)
 #ifdef SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG
     case SIMPLE_ARRAY_COMPLEX_LONG_FLOAT_WIDETAG:
 #endif
-       boxed = UNBOXED_PAGE;
+       boxed = UNBOXED_PAGE_FLAG;
        break;
     default:
        return;
@@ -2339,11 +2315,11 @@ maybe_adjust_large_object(lispobj *where)
     gc_assert(page_table[first_page].first_object_offset == 0);
 
     next_page = first_page;
-    remaining_bytes = nwords*4;
+    remaining_bytes = nwords*N_WORD_BYTES;
     while (remaining_bytes > PAGE_BYTES) {
        gc_assert(page_table[next_page].gen == from_space);
-       gc_assert((page_table[next_page].allocated == BOXED_PAGE)
-                 || (page_table[next_page].allocated == UNBOXED_PAGE));
+       gc_assert((page_table[next_page].allocated == BOXED_PAGE_FLAG)
+                 || (page_table[next_page].allocated == UNBOXED_PAGE_FLAG));
        gc_assert(page_table[next_page].large_object);
        gc_assert(page_table[next_page].first_object_offset ==
                  -PAGE_BYTES*(next_page-first_page));
@@ -2378,8 +2354,8 @@ maybe_adjust_large_object(lispobj *where)
     next_page++;
     while ((old_bytes_used == PAGE_BYTES) &&
           (page_table[next_page].gen == from_space) &&
-          ((page_table[next_page].allocated == UNBOXED_PAGE)
-           || (page_table[next_page].allocated == BOXED_PAGE)) &&
+          ((page_table[next_page].allocated == UNBOXED_PAGE_FLAG)
+           || (page_table[next_page].allocated == BOXED_PAGE_FLAG)) &&
           page_table[next_page].large_object &&
           (page_table[next_page].first_object_offset ==
            -(next_page - first_page)*PAGE_BYTES)) {
@@ -2390,7 +2366,7 @@ maybe_adjust_large_object(lispobj *where)
        gc_assert(page_table[next_page].write_protected == 0);
 
        old_bytes_used = page_table[next_page].bytes_used;
-       page_table[next_page].allocated = FREE_PAGE;
+       page_table[next_page].allocated = FREE_PAGE_FLAG;
        page_table[next_page].bytes_used = 0;
        bytes_freed += old_bytes_used;
        next_page++;
@@ -2430,13 +2406,13 @@ preserve_pointer(void *addr)
 
     /* quick check 1: Address is quite likely to have been invalid. */
     if ((addr_page_index == -1)
-       || (page_table[addr_page_index].allocated == FREE_PAGE)
+       || (page_table[addr_page_index].allocated == FREE_PAGE_FLAG)
        || (page_table[addr_page_index].bytes_used == 0)
        || (page_table[addr_page_index].gen != from_space)
        /* Skip if already marked dont_move. */
        || (page_table[addr_page_index].dont_move != 0))
        return;
-    gc_assert(!(page_table[addr_page_index].allocated & OPEN_REGION_PAGE));
+    gc_assert(!(page_table[addr_page_index].allocated&OPEN_REGION_PAGE_FLAG));
     /* (Now that we know that addr_page_index is in range, it's
      * safe to index into page_table[] with it.) */
     region_allocation = page_table[addr_page_index].allocated;
@@ -2486,7 +2462,7 @@ preserve_pointer(void *addr)
         * free area in which case it's ignored here. Note it gets
         * through the valid pointer test above because the tail looks
         * like conses. */
-       if ((page_table[addr_page_index].allocated == FREE_PAGE)
+       if ((page_table[addr_page_index].allocated == FREE_PAGE_FLAG)
            || (page_table[addr_page_index].bytes_used == 0)
            /* Check the offset within the page. */
            || (((unsigned)addr & (PAGE_BYTES - 1))
@@ -2525,7 +2501,7 @@ preserve_pointer(void *addr)
        /* Check whether this is the last page in this contiguous block.. */
        if ((page_table[i].bytes_used < PAGE_BYTES)
            /* ..or it is PAGE_BYTES and is the last in the block */
-           || (page_table[i+1].allocated == FREE_PAGE)
+           || (page_table[i+1].allocated == FREE_PAGE_FLAG)
            || (page_table[i+1].bytes_used == 0) /* next page free */
            || (page_table[i+1].gen != from_space) /* diff. gen */
            || (page_table[i+1].first_object_offset == 0))
@@ -2556,16 +2532,16 @@ update_page_write_prot(int page)
     int j;
     int wp_it = 1;
     void **page_addr = (void **)page_address(page);
-    int num_words = page_table[page].bytes_used / 4;
+    int num_words = page_table[page].bytes_used / N_WORD_BYTES;
 
     /* Shouldn't be a free page. */
-    gc_assert(page_table[page].allocated != FREE_PAGE);
+    gc_assert(page_table[page].allocated != FREE_PAGE_FLAG);
     gc_assert(page_table[page].bytes_used != 0);
 
     /* Skip if it's already write-protected, pinned, or unboxed */
     if (page_table[page].write_protected
        || page_table[page].dont_move
-       || (page_table[page].allocated & UNBOXED_PAGE))
+       || (page_table[page].allocated & UNBOXED_PAGE_FLAG))
        return (0);
 
     /* Scan the page for pointers to younger generations or the
@@ -2578,7 +2554,7 @@ update_page_write_prot(int page)
        /* Check that it's in the dynamic space */
        if (index != -1)
            if (/* Does it point to a younger or the temp. generation? */
-               ((page_table[index].allocated != FREE_PAGE)
+               ((page_table[index].allocated != FREE_PAGE_FLAG)
                 && (page_table[index].bytes_used != 0)
                 && ((page_table[index].gen < gen)
                     || (page_table[index].gen == NUM_GENERATIONS)))
@@ -2653,7 +2629,7 @@ scavenge_generation(int generation)
 #endif
 
     for (i = 0; i < last_free_page; i++) {
-       if ((page_table[i].allocated & BOXED_PAGE)
+       if ((page_table[i].allocated & BOXED_PAGE_FLAG)
            && (page_table[i].bytes_used != 0)
            && (page_table[i].gen == generation)) {
            int last_page,j;
@@ -2668,7 +2644,7 @@ scavenge_generation(int generation)
                    write_protected && page_table[last_page].write_protected;
                if ((page_table[last_page].bytes_used < PAGE_BYTES)
                    /* Or it is PAGE_BYTES and is the last in the block */
-                   || (!(page_table[last_page+1].allocated & BOXED_PAGE))
+                   || (!(page_table[last_page+1].allocated & BOXED_PAGE_FLAG))
                    || (page_table[last_page+1].bytes_used == 0)
                    || (page_table[last_page+1].gen != generation)
                    || (page_table[last_page+1].first_object_offset == 0))
@@ -2699,7 +2675,7 @@ scavenge_generation(int generation)
     /* Check that none of the write_protected pages in this generation
      * have been written to. */
     for (i = 0; i < NUM_PAGES; i++) {
-       if ((page_table[i].allocation ! =FREE_PAGE)
+       if ((page_table[i].allocation != FREE_PAGE_FLAG)
            && (page_table[i].bytes_used != 0)
            && (page_table[i].gen == generation)
            && (page_table[i].write_protected_cleared != 0)) {
@@ -2753,7 +2729,7 @@ scavenge_newspace_generation_one_scan(int generation)
           generation));
     for (i = 0; i < last_free_page; i++) {
        /* Note that this skips over open regions when it encounters them. */
-       if ((page_table[i].allocated & BOXED_PAGE)
+       if ((page_table[i].allocated & BOXED_PAGE_FLAG)
            && (page_table[i].bytes_used != 0)
            && (page_table[i].gen == generation)
            && ((page_table[i].write_protected == 0)
@@ -2781,7 +2757,7 @@ scavenge_newspace_generation_one_scan(int generation)
                 * contiguous block */
                if ((page_table[last_page].bytes_used < PAGE_BYTES)
                    /* Or it is PAGE_BYTES and is the last in the block */
-                   || (!(page_table[last_page+1].allocated & BOXED_PAGE))
+                   || (!(page_table[last_page+1].allocated & BOXED_PAGE_FLAG))
                    || (page_table[last_page+1].bytes_used == 0)
                    || (page_table[last_page+1].gen != generation)
                    || (page_table[last_page+1].first_object_offset == 0))
@@ -2895,12 +2871,10 @@ scavenge_newspace_generation(int generation)
 
            /* Work through previous_new_areas. */
            for (i = 0; i < previous_new_areas_index; i++) {
-               /* FIXME: All these bare *4 and /4 should be something
-                * like BYTES_PER_WORD or WBYTES. */
                int page = (*previous_new_areas)[i].page;
                int offset = (*previous_new_areas)[i].offset;
-               int size = (*previous_new_areas)[i].size / 4;
-               gc_assert((*previous_new_areas)[i].size % 4 == 0);
+               int size = (*previous_new_areas)[i].size / N_WORD_BYTES;
+               gc_assert((*previous_new_areas)[i].size % N_WORD_BYTES == 0);
                scavenge(page_address(page)+offset, size);
            }
 
@@ -2922,7 +2896,7 @@ scavenge_newspace_generation(int generation)
     /* Check that none of the write_protected pages in this generation
      * have been written to. */
     for (i = 0; i < NUM_PAGES; i++) {
-       if ((page_table[i].allocation != FREE_PAGE)
+       if ((page_table[i].allocation != FREE_PAGE_FLAG)
            && (page_table[i].bytes_used != 0)
            && (page_table[i].gen == generation)
            && (page_table[i].write_protected_cleared != 0)
@@ -2945,7 +2919,7 @@ unprotect_oldspace(void)
     int i;
 
     for (i = 0; i < last_free_page; i++) {
-       if ((page_table[i].allocated != FREE_PAGE)
+       if ((page_table[i].allocated != FREE_PAGE_FLAG)
            && (page_table[i].bytes_used != 0)
            && (page_table[i].gen == from_space)) {
            void *page_start;
@@ -2966,7 +2940,6 @@ unprotect_oldspace(void)
  * assumes that all objects have been copied or promoted to an older
  * generation. Bytes_allocated and the generation bytes_allocated
  * counter are updated. The number of bytes freed is returned. */
-extern void i586_bzero(void *addr, int nbytes);
 static int
 free_oldspace(void)
 {
@@ -2978,7 +2951,7 @@ free_oldspace(void)
     do {
        /* Find a first page for the next region of pages. */
        while ((first_page < last_free_page)
-              && ((page_table[first_page].allocated == FREE_PAGE)
+              && ((page_table[first_page].allocated == FREE_PAGE_FLAG)
                   || (page_table[first_page].bytes_used == 0)
                   || (page_table[first_page].gen != from_space)))
            first_page++;
@@ -2994,7 +2967,7 @@ free_oldspace(void)
            bytes_freed += page_table[last_page].bytes_used;
            generations[page_table[last_page].gen].bytes_allocated -=
                page_table[last_page].bytes_used;
-           page_table[last_page].allocated = FREE_PAGE;
+           page_table[last_page].allocated = FREE_PAGE_FLAG;
            page_table[last_page].bytes_used = 0;
 
            /* Remove any write-protection. We should be able to rely
@@ -3010,7 +2983,7 @@ free_oldspace(void)
            last_page++;
        }
        while ((last_page < last_free_page)
-              && (page_table[last_page].allocated != FREE_PAGE)
+              && (page_table[last_page].allocated != FREE_PAGE_FLAG)
               && (page_table[last_page].bytes_used != 0)
               && (page_table[last_page].gen == from_space));
 
@@ -3027,23 +3000,14 @@ free_oldspace(void)
            os_invalidate(page_start, PAGE_BYTES*(last_page-first_page));
            addr = os_validate(page_start, PAGE_BYTES*(last_page-first_page));
            if (addr == NULL || addr != page_start) {
-               /* Is this an error condition? I couldn't really tell from
-                * the old CMU CL code, which fprintf'ed a message with
-                * an exclamation point at the end. But I've never seen the
-                * message, so it must at least be unusual..
-                *
-                * (The same condition is also tested for in gc_free_heap.)
-                *
-                * -- WHN 19991129 */
-               lose("i586_bzero: page moved, 0x%08x ==> 0x%08x",
-                    page_start,
+               lose("free_oldspace: page moved, 0x%08x ==> 0x%08x",page_start,
                     addr);
            }
        } else {
            int *page_start;
 
            page_start = (int *)page_address(first_page);
-           i586_bzero(page_start, PAGE_BYTES*(last_page-first_page));
+           memset(page_start, 0,PAGE_BYTES*(last_page-first_page));
        }
 
        first_page = last_page;
@@ -3111,7 +3075,7 @@ verify_space(lispobj *start, size_t words)
            if (page_index != -1) {
                /* If it's within the dynamic space it should point to a used
                 * page. XX Could check the offset too. */
-               if ((page_table[page_index].allocated != FREE_PAGE)
+               if ((page_table[page_index].allocated != FREE_PAGE_FLAG)
                    && (page_table[page_index].bytes_used == 0))
                    lose ("Ptr %x @ %x sees free page.", thing, start);
                /* Check that it doesn't point to a forwarding pointer! */
@@ -3156,6 +3120,9 @@ verify_space(lispobj *start, size_t words)
                case COMPLEX_WIDETAG:
                case SIMPLE_ARRAY_WIDETAG:
                case COMPLEX_BASE_STRING_WIDETAG:
+#ifdef COMPLEX_CHARACTER_STRING_WIDETAG
+               case COMPLEX_CHARACTER_STRING_WIDETAG:
+#endif
                case COMPLEX_VECTOR_NIL_WIDETAG:
                case COMPLEX_BIT_VECTOR_WIDETAG:
                case COMPLEX_VECTOR_WIDETAG:
@@ -3164,7 +3131,7 @@ verify_space(lispobj *start, size_t words)
                case FUNCALLABLE_INSTANCE_HEADER_WIDETAG:
                case VALUE_CELL_HEADER_WIDETAG:
                case SYMBOL_HEADER_WIDETAG:
-               case BASE_CHAR_WIDETAG:
+               case CHARACTER_WIDETAG:
                case UNBOUND_MARKER_WIDETAG:
                case INSTANCE_HEADER_WIDETAG:
                case FDEFN_WIDETAG:
@@ -3242,6 +3209,9 @@ verify_space(lispobj *start, size_t words)
                case COMPLEX_LONG_FLOAT_WIDETAG:
 #endif
                case SIMPLE_BASE_STRING_WIDETAG:
+#ifdef SIMPLE_CHARACTER_STRING_WIDETAG
+               case SIMPLE_CHARACTER_STRING_WIDETAG:
+#endif
                case SIMPLE_BIT_VECTOR_WIDETAG:
                case SIMPLE_ARRAY_NIL_WIDETAG:
                case SIMPLE_ARRAY_UNSIGNED_BYTE_2_WIDETAG:
@@ -3326,7 +3296,7 @@ verify_generation(int  generation)
     int i;
 
     for (i = 0; i < last_free_page; i++) {
-       if ((page_table[i].allocated != FREE_PAGE)
+       if ((page_table[i].allocated != FREE_PAGE_FLAG)
            && (page_table[i].bytes_used != 0)
            && (page_table[i].gen == generation)) {
            int last_page;
@@ -3365,7 +3335,7 @@ verify_zero_fill(void)
     int page;
 
     for (page = 0; page < last_free_page; page++) {
-       if (page_table[page].allocated == FREE_PAGE) {
+       if (page_table[page].allocated == FREE_PAGE_FLAG) {
            /* The whole page should be zero filled. */
            int *start_addr = (int *)page_address(page);
            int size = 1024;
@@ -3380,7 +3350,7 @@ verify_zero_fill(void)
            if (free_bytes > 0) {
                int *start_addr = (int *)((unsigned)page_address(page)
                                          + page_table[page].bytes_used);
-               int size = free_bytes / 4;
+               int size = free_bytes / N_WORD_BYTES;
                int i;
                for (i = 0; i < size; i++) {
                    if (start_addr[i] != 0) {
@@ -3423,7 +3393,7 @@ write_protect_generation_pages(int generation)
     gc_assert(generation < NUM_GENERATIONS);
 
     for (i = 0; i < last_free_page; i++)
-       if ((page_table[i].allocated == BOXED_PAGE)
+       if ((page_table[i].allocated == BOXED_PAGE_FLAG)
            && (page_table[i].bytes_used != 0)
            && !page_table[i].dont_move
            && (page_table[i].gen == generation))  {
@@ -3517,8 +3487,8 @@ garbage_collect_generation(int generation, int raise)
     for_each_thread(th) {
        void **ptr;
        void **esp=(void **)-1;
-       int i,free;
 #ifdef LISP_FEATURE_SB_THREAD
+       int i,free;
        if(th==arch_os_get_current_thread()) {
            esp = (void **) &raise;
        } else {
@@ -3543,7 +3513,7 @@ garbage_collect_generation(int generation, int raise)
        }
     }
 
-#if QSHOW
+#ifdef QSHOW
     if (gencgc_verbose > 1) {
        int num_dont_move_pages = count_dont_move_pages();
        fprintf(stderr,
@@ -3708,7 +3678,7 @@ update_x86_dynamic_space_free_pointer(void)
     int i;
 
     for (i = 0; i < NUM_PAGES; i++)
-       if ((page_table[i].allocated != FREE_PAGE)
+       if ((page_table[i].allocated != FREE_PAGE_FLAG)
            && (page_table[i].bytes_used != 0))
            last_page = i;
 
@@ -3859,15 +3829,15 @@ gc_free_heap(void)
 
     for (page = 0; page < NUM_PAGES; page++) {
        /* Skip free pages which should already be zero filled. */
-       if (page_table[page].allocated != FREE_PAGE) {
+       if (page_table[page].allocated != FREE_PAGE_FLAG) {
            void *page_start, *addr;
 
            /* Mark the page free. The other slots are assumed invalid
-            * when it is a FREE_PAGE and bytes_used is 0 and it
+            * when it is a FREE_PAGE_FLAG and bytes_used is 0 and it
             * should not be write-protected -- except that the
             * generation is used for the current region but it sets
             * that up. */
-           page_table[page].allocated = FREE_PAGE;
+           page_table[page].allocated = FREE_PAGE_FLAG;
            page_table[page].bytes_used = 0;
 
            /* Zero the page. */
@@ -3887,7 +3857,7 @@ gc_free_heap(void)
        } else if (gencgc_zero_check_during_free_heap) {
            /* Double-check that the page is zero filled. */
            int *page_start, i;
-           gc_assert(page_table[page].allocated == FREE_PAGE);
+           gc_assert(page_table[page].allocated == FREE_PAGE_FLAG);
            gc_assert(page_table[page].bytes_used == 0);
            page_start = (int *)page_address(page);
            for (i=0; i<1024; i++) {
@@ -3947,7 +3917,7 @@ gc_init(void)
     /* Initialize each page structure. */
     for (i = 0; i < NUM_PAGES; i++) {
        /* Initialize all pages as free. */
-       page_table[i].allocated = FREE_PAGE;
+       page_table[i].allocated = FREE_PAGE_FLAG;
        page_table[i].bytes_used = 0;
 
        /* Pages are not write-protected at startup. */
@@ -3997,7 +3967,7 @@ gencgc_pickup_dynamic(void)
 
     do {
        lispobj *first,*ptr= (lispobj *)page_address(page);
-       page_table[page].allocated = BOXED_PAGE;
+       page_table[page].allocated = BOXED_PAGE_FLAG;
        page_table[page].gen = 0;
        page_table[page].bytes_used = PAGE_BYTES;
        page_table[page].large_object = 0;
@@ -4040,8 +4010,12 @@ char *
 alloc(int nbytes)
 {
     struct thread *th=arch_os_get_current_thread();
-    struct alloc_region *region= 
+    struct alloc_region *region=
+#ifdef LISP_FEATURE_SB_THREAD
        th ? &(th->alloc_region) : &boxed_region; 
+#else
+        &boxed_region; 
+#endif
     void *new_obj;
     void *new_free_pointer;
 
@@ -4090,29 +4064,6 @@ alloc(int nbytes)
     new_obj = gc_alloc_with_region(nbytes,0,region,0);
     return (new_obj);
 }
-
-\f
-/* Find the code object for the given pc, or return NULL on failure.
- *
- * FIXME: PC shouldn't be lispobj*, should it? Maybe void*? */
-lispobj *
-component_ptr_from_pc(lispobj *pc)
-{
-    lispobj *object = NULL;
-
-    if ( (object = search_read_only_space(pc)) )
-       ;
-    else if ( (object = search_static_space(pc)) )
-       ;
-    else
-       object = search_dynamic_space(pc);
-
-    if (object) /* if we found something */
-       if (widetag_of(*object) == CODE_HEADER_WIDETAG) /* if it's a code object */
-           return(object);
-
-    return (NULL);
-}
 \f
 /*
  * shared support for the OS-dependent signal handlers which
@@ -4136,7 +4087,7 @@ gencgc_handle_wp_violation(void* fault_addr)
 {
     int  page_index = find_page_index(fault_addr);
 
-#if defined QSHOW_SIGNALS
+#ifdef QSHOW_SIGNALS
     FSHOW((stderr, "heap WP violation? fault_addr=%x, page_index=%d\n",
           fault_addr, page_index));
 #endif