[commit: ghc] master: rts: Use BITS_IN macro in bitmap calculations (3cd1305)

[git at git.haskell.org]

Repository : ssh://git@git.haskell.org/ghc

On branch  : master
Link       : http://ghc.haskell.org/trac/ghc/changeset/3cd1305ffcc4a5e3269aeb2e0694dddb7ca480d0/ghc

>---------------------------------------------------------------

commit 3cd1305ffcc4a5e3269aeb2e0694dddb7ca480d0
Author: Ömer Sinan Ağacan <omeragacan at gmail.com>
Date:   Tue Feb 6 13:29:50 2018 -0500

    rts: Use BITS_IN macro in bitmap calculations
    
    Reviewers: bgamari, erikd, simonmar
    
    Reviewed By: bgamari
    
    Subscribers: rwbarton, thomie, carter
    
    Differential Revision: https://phabricator.haskell.org/D4386


>---------------------------------------------------------------

3cd1305ffcc4a5e3269aeb2e0694dddb7ca480d0
 rts/sm/Compact.h | 12 ++++++------
 rts/sm/GC.c      |  4 ++--
 2 files changed, 8 insertions(+), 8 deletions(-)

diff --git a/rts/sm/Compact.h b/rts/sm/Compact.h
index 6dcb50b..63abfc7 100644
--- a/rts/sm/Compact.h
+++ b/rts/sm/Compact.h
@@ -20,8 +20,8 @@ mark(StgPtr p, bdescr *bd)
 {
     uint32_t offset_within_block = p - bd->start; // in words
     StgPtr bitmap_word = (StgPtr)bd->u.bitmap +
-        (offset_within_block / (sizeof(W_)*BITS_PER_BYTE));
-    StgWord bit_mask = (StgWord)1 << (offset_within_block & (sizeof(W_)*BITS_PER_BYTE - 1));
+        (offset_within_block / BITS_IN(W_));
+    StgWord bit_mask = (StgWord)1 << (offset_within_block & (BITS_IN(W_) - 1));
     *bitmap_word |= bit_mask;
 }
 
@@ -30,8 +30,8 @@ unmark(StgPtr p, bdescr *bd)
 {
     uint32_t offset_within_block = p - bd->start; // in words
     StgPtr bitmap_word = (StgPtr)bd->u.bitmap +
-        (offset_within_block / (sizeof(W_)*BITS_PER_BYTE));
-    StgWord bit_mask = (StgWord)1 << (offset_within_block & (sizeof(W_)*BITS_PER_BYTE - 1));
+        (offset_within_block / BITS_IN(W_));
+    StgWord bit_mask = (StgWord)1 << (offset_within_block & (BITS_IN(W_) - 1));
     *bitmap_word &= ~bit_mask;
 }
 
@@ -40,8 +40,8 @@ is_marked(StgPtr p, bdescr *bd)
 {
     uint32_t offset_within_block = p - bd->start; // in words
     StgPtr bitmap_word = (StgPtr)bd->u.bitmap +
-        (offset_within_block / (sizeof(W_)*BITS_PER_BYTE));
-    StgWord bit_mask = (StgWord)1 << (offset_within_block & (sizeof(W_)*BITS_PER_BYTE - 1));
+        (offset_within_block / BITS_IN(W_));
+    StgWord bit_mask = (StgWord)1 << (offset_within_block & (BITS_IN(W_)- 1));
     return (*bitmap_word & bit_mask);
 }
 
diff --git a/rts/sm/GC.c b/rts/sm/GC.c
index 197b466..54797ba 100644
--- a/rts/sm/GC.c
+++ b/rts/sm/GC.c
@@ -1372,7 +1372,7 @@ prepare_collected_gen (generation *gen)
         bdescr *bitmap_bdescr;
         StgWord *bitmap;
 
-        bitmap_size = gen->n_old_blocks * BLOCK_SIZE / (sizeof(W_)*BITS_PER_BYTE);
+        bitmap_size = gen->n_old_blocks * BLOCK_SIZE / BITS_IN(W_);
 
         if (bitmap_size > 0) {
             bitmap_bdescr = allocGroup((StgWord)BLOCK_ROUND_UP(bitmap_size)
@@ -1390,7 +1390,7 @@ prepare_collected_gen (generation *gen)
             // block descriptor.
             for (bd=gen->old_blocks; bd != NULL; bd = bd->link) {
                 bd->u.bitmap = bitmap;
-                bitmap += BLOCK_SIZE_W / (sizeof(W_)*BITS_PER_BYTE);
+                bitmap += BLOCK_SIZE_W / BITS_IN(W_);
 
                 // Also at this point we set the BF_MARKED flag
                 // for this block.  The invariant is that