Changeset 1897 for trunk/src/kmk

Timestamp:

Oct 21, 2008, 3:21:39 AM (17 years ago)

Author:

bird

Message:

kmk: added strcache2_get_ptr_hash for more efficent hashing by string pool users; replacing hash1 with that and hash2 with hash1, thus avoiding unnecessary hash2 calculations.

Location:

trunk/src/kmk

Files:

• dir.c (modified) (6 diffs)
• file.c (modified) (2 diffs)
• make.h (modified) (1 diff)
• strcache2.c (modified) (1 diff)
• strcache2.h (modified) (3 diffs)
• variable.c (modified) (2 diffs)

trunk/src/kmk/dir.c

@@ -264 +264 @@
   ISTRING_HASH_1 (key->path_key, hash);
 # else  /* CONFIG_WITH_STRCACHE2 */
-  hash = strcache_get_hash1 (key->path_key);
+  hash = strcache2_get_ptr_hash (&file_cache, key->path_key);
 # endif /* CONFIG_WITH_STRCACHE2 */
   hash ^= ((unsigned int) key->dev << 4) ^ (unsigned int) key->ctime;
@@ -291 +291 @@
   ISTRING_HASH_2 (key->path_key, hash);
 # else  /* CONFIG_WITH_STRCACHE2 */
-  hash = strcache_get_hash2 (key->path_key);
+  hash = strcache2_get_hash1 (&file_cache, key->path_key);
 # endif /* CONFIG_WITH_STRCACHE2 */
   hash ^= ((unsigned int) key->dev << 4) ^ (unsigned int) ~key->ctime;
@@ -383 +383 @@
   return_ISTRING_HASH_1 (((const struct directory *) key)->name);
 #else
-  return strcache_get_hash1 (((const struct directory *) key)->name);
+  return strcache2_get_ptr_hash (&file_cache, ((const struct directory *) key)->name);
 #endif
 }
@@ -393 +393 @@
   return_ISTRING_HASH_2 (((const struct directory *) key)->name);
 #else
-  return strcache_get_hash2 (((const struct directory *) key)->name);
+  return strcache2_get_hash1 (&file_cache, ((const struct directory *) key)->name);
 #endif
 }
@@ -439 +439 @@
   return_ISTRING_HASH_1 (((struct dirfile const *) key)->name);
 #else
-  return strcache_get_hash1 (((struct dirfile const *) key)->name);
+  return strcache2_get_ptr_hash (&file_cache, ((struct dirfile const *) key)->name);
 #endif
 }
@@ -449 +449 @@
   return_ISTRING_HASH_2 (((struct dirfile const *) key)->name);
 #else
-  return strcache_get_hash2 (((struct dirfile const *) key)->name);
+  return strcache2_get_hash1 (&file_cache, ((struct dirfile const *) key)->name);
 #endif
 }

trunk/src/kmk/file.c

@@ -47 +47 @@
   return_ISTRING_HASH_1 (((struct file const *) key)->hname);
 #else  /* CONFIG_WITH_STRCACHE2 */
-  return strcache_get_hash1 (((struct file const *) key)->hname);
+  return strcache2_get_ptr_hash (&file_cache, ((struct file const *) key)->hname);
 #endif /* CONFIG_WITH_STRCACHE2 */
 }
@@ -57 +57 @@
   return_ISTRING_HASH_2 (((struct file const *) key)->hname);
 #else  /* CONFIG_WITH_STRCACHE2 */
-  return strcache_get_hash1 (((struct file const *) key)->hname);
+  return strcache2_get_ptr_hash (&file_cache, ((struct file const *) key)->hname);
 #endif /* CONFIG_WITH_STRCACHE2 */
 }

trunk/src/kmk/make.h

@@ -601 +601 @@
 # define strcache_add(str)          strcache2_add_file(&file_strcache, str, strlen (str))
 # define strcache_add_len(str, len) strcache2_add_file(&file_strcache, str, len)
-# define strcache_get_len(str)      strcache2_get_len(&file_strcache, str)
-# define strcache_get_hash1(str)    strcache2_get_hash1(&file_strcache, str)
-# define strcache_get_hash2(str)    strcache2_get_hash2(&file_strcache, str)
+# define strcache_get_len(str)      strcache2_get_len(&file_strcache, str) /* FIXME: replace this and related checks ... */
 
 #endif /* CONFIG_WITH_STRCACHE2 */

trunk/src/kmk/strcache2.c

@@ -526 +526 @@
 
   size = length + 1 + sizeof (struct strcache2_entry);
-  size = (size + sizeof (void *) - 1) & ~(sizeof (void *) - 1U);
+  size = (size + STRCACHE2_ENTRY_ALIGNMENT - 1) & ~(STRCACHE2_ENTRY_ALIGNMENT - 1U);
 
   seg = cache->seg_head;

trunk/src/kmk/strcache2.h

@@ -28 +28 @@
 #define ___strcache2_h
 
+#ifndef CHAR_BIT
+# error "include after make.h!"
+#endif
+
 /* string cache memory segment. */
 struct strcache2_seg
@@ -46 +50 @@
     unsigned int length;
 };
+
+/* The entry alignment.
+   As it is very difficult to derive this from any #define or typedef, a
+   default value of 16 (chars) was choosen as this fits most platforms.
+   For odd platforms, just override this define.  */
+#ifndef STRCACHE2_ENTRY_ALIGN_SHIFT
+# define STRCACHE2_ENTRY_ALIGN_SHIFT    4
+#endif
+#define STRCACHE2_ENTRY_ALIGNMENT       (1 << STRCACHE2_ENTRY_ALIGN_SHIFT)
+
 
 struct strcache2
@@ -123 +137 @@
 }
 
+/* Get the pointer hash value for the string.
+
+   This takes the string address, shift out the bits that are always zero
+   due to alignment, and then returns the unsigned integer value of it.
+
+   The results from using this is generally better than for any of the
+   other hash values.  It is also sligtly faster code as it does not
+   involve any memory accesses, just a right SHIFT and an optional AND. */
+MY_INLINE unsigned int
+strcache2_get_ptr_hash (struct strcache2 *cache, const char *str)
+{
+  (void)cache;
+  return (size_t)str >> STRCACHE2_ENTRY_ALIGN_SHIFT;
+}
+
 /* Get the user value for the string. */
 MY_INLINE void *

trunk/src/kmk/variable.c

@@ -118 +118 @@
 #else
   /* all requests are served from the cache. */
-  return strcache2_get_hash1 (&variable_strcache, key->name);
+  return strcache2_get_ptr_hash (&variable_strcache, key->name);
 #endif
 }
@@ -485 +485 @@
 #ifdef KMK /* bird: speed */
       struct hash_table *ht = &setlist->set->table;
-      unsigned int hash_1 = strcache2_get_hash1 (&variable_strcache, name);
+      unsigned int hash_1 = strcache2_get_ptr_hash (&variable_strcache, name);
       struct variable *v;