[project @ 2003-03-31 19:19:34 by sof]

[ghc-hetmet.git] / ghc / rts / MBlock.c

diff --git a/ghc/rts/MBlock.c b/ghc/rts/MBlock.c
index 6011709..1bf4e80 100644 (file)
--- a/ghc/rts/MBlock.c
+++ b/ghc/rts/MBlock.c
@@ -1,5 +1,5 @@
 /* -----------------------------------------------------------------------------
- * $Id: MBlock.c,v 1.36 2002/11/05 09:31:37 simonmar Exp $
+ * $Id: MBlock.c,v 1.44 2003/03/26 02:12:38 sof Exp $
  *
  * (c) The GHC Team 1998-1999
  *
@@ -50,13 +50,9 @@ lnat mblocks_allocated = 0;
    The MBlock Map: provides our implementation of HEAP_ALLOCED()
    -------------------------------------------------------------------------- */
 
-StgWord8 mblock_map[4096]; // initially all zeros
-
-static void
-mblockIsHeap (void *p)
-{
-    mblock_map[((StgWord)p & ~MBLOCK_MASK) >> MBLOCK_SHIFT] = 1;
-}
+#ifdef MBLOCK_MAP_SIZE
+StgWord8 mblock_map[MBLOCK_MAP_SIZE]; // initially all zeros
+#endif
 
 /* -----------------------------------------------------------------------------
    Allocate new mblock(s)
@@ -120,18 +116,19 @@ my_mmap (void *addr, int size)
     if(!addr || err)   // try to allocate anywhere
        err = vm_allocate(mach_task_self(),(vm_address_t*) &ret, size, TRUE);
        
-    if(err)
-       ret = (void*) -1;
+    if(err) // don't know what the error codes mean exactly
+       barf("memory allocation failed (requested %d bytes)", size);
     else
        vm_protect(mach_task_self(),ret,size,FALSE,VM_PROT_READ|VM_PROT_WRITE);
 #else
-    ret = mmap(addr, size, PROT_READ | PROT_WRITE, 
+    ret = mmap(addr, size, PROT_READ | PROT_WRITE | PROT_EXEC, 
               MAP_ANON | MAP_PRIVATE, -1, 0);
 #endif
 
     if (ret == (void *)-1) {
        if (errno == ENOMEM) {
-           barf("out of memory (requested %d bytes)", size);
+           prog_belch("out of memory (requested %d bytes)", size);
+           stg_exit(EXIT_FAILURE);
        } else {
            barf("getMBlock: mmap failed");
        }
@@ -156,16 +153,25 @@ gen_map_mblocks (int size)
     
     // unmap the slop bits around the chunk we allocated
     slop = (W_)ret & MBLOCK_MASK;
-       
+    
     if (munmap(ret, MBLOCK_SIZE - slop) == -1) {
-       barf("gen_map_mblocks: munmap failed");
+      barf("gen_map_mblocks: munmap failed");
     }
     if (slop > 0 && munmap(ret+size-slop, slop) == -1) {
-       barf("gen_map_mblocks: munmap failed");
+      barf("gen_map_mblocks: munmap failed");
     }
-    
+
     // ToDo: if we happened to get an aligned block, then don't
-    // unmap the excess, just use it.
+    // unmap the excess, just use it. For this to work, you
+    // need to keep in mind the following:
+    //     * Calling my_mmap() with an 'addr' arg pointing to
+    //       already my_mmap()ed space is OK and won't fail.
+    //     * If my_mmap() can't satisfy the request at the
+    //       given 'next_request' address in getMBlocks(), that
+    //       you unmap the extra mblock mmap()ed here (or simply
+    //       satisfy yourself that the slop introduced isn't worth
+    //       salvaging.)
+    // 
 
     // next time, try after the block we just got.
     ret += MBLOCK_SIZE - slop;
@@ -192,10 +198,10 @@ getMBlocks(nat n)
 
       if (((W_)ret & MBLOCK_MASK) != 0) {
          // misaligned block!
-#ifdef DEBUG
-         belch("getMBlock: misaligned block %p returned when allocating %d megablock(s) at %p", ret, n, next_request);
+#if 0 // defined(DEBUG)
+         belch("warning: getMBlock: misaligned block %p returned when allocating %d megablock(s) at %p", ret, n, next_request);
 #endif
-         
+
          // unmap this block...
          if (munmap(ret, size) == -1) {
              barf("getMBlock: munmap failed");
@@ -213,7 +219,7 @@ getMBlocks(nat n)
 
   // fill in the table
   for (i = 0; i < n; i++) {
-      mblockIsHeap( ret + i * MBLOCK_SIZE );
+      MARK_HEAP_ALLOCED( ret + i * MBLOCK_SIZE );
   }
 
   mblocks_allocated += n;
@@ -316,7 +322,7 @@ getMBlocks(nat n)
   
   // fill in the table
   for (i = 0; i < n; i++) {
-      mblockIsHeap( ret + i * MBLOCK_SIZE );
+      MARK_HEAP_ALLOCED ( ret + i * MBLOCK_SIZE );
   }
 
   return ret;