0.pre7.58:

[sbcl.git] / src / runtime / gencgc.h

diff --git a/src/runtime/gencgc.h b/src/runtime/gencgc.h
index 9b5b0dd..2852b1c 100644 (file)
--- a/src/runtime/gencgc.h
+++ b/src/runtime/gencgc.h
@@ -30,11 +30,12 @@ struct page {
         * (If the page is written into, we catch the exception, make
         * the page writable, and clear this flag.) */
         write_protected :1,
-       /* This flag is set when the above write_protected flag is
-         * cleared by the sigbus handler. This is useful for
-         * re-scavenging pages that are written during a GC. */
+       /* This flag is set when the above write_protected flag is 
+        * cleared by the SIGBUS handler (or SIGSEGV handler, for some
+        * OSes). This is useful for * re-scavenging pages that are
+        * written during a GC. */
        write_protected_cleared :1,
-       /* The region the page is allocated to: 0 for a free page; 1
+       /* the region the page is allocated to: 0 for a free page; 1
          * for boxed objects; 2 for unboxed objects. If the page is
          * free the following slots are invalid (well the bytes_used
          * must be 0). */
@@ -65,6 +66,7 @@ struct page {
     int  first_object_offset;
 };
 
+/* values for the page.allocated field */
 #define FREE_PAGE 0
 #define BOXED_PAGE 1
 #define UNBOXED_PAGE 2
@@ -81,7 +83,7 @@ struct alloc_region {
     void  *free_pointer;
     void  *end_addr; /* pointer to the byte after the last usable byte */
 
-    /* needed when closing the region */
+    /* These are needed when closing the region. */
     int  first_page;
     int  last_page;
     void  *start_addr;
@@ -97,4 +99,5 @@ void sniff_code_object(struct code *code, unsigned displacement);
 int  update_x86_dynamic_space_free_pointer(void);
 void  gc_alloc_update_page_tables(int unboxed,
                                  struct alloc_region *alloc_region);
+
 #endif _GENCGC_H_