From: Sebastian Hack <hack@ipd.info.uni-karlsruhe.de>
Date: Thu, 21 Jun 2007 16:47:46 +0000 (+0000)
Subject: Added string hashing function
X-Git-Url: http://nsz.repo.hu/git/?a=commitdiff_plain;h=148554545066eb065e992d458c98bf01bf6adf55;p=libfirm

Added string hashing function

[r14705]
---

diff --git a/include/libfirm/adt/hashptr.h b/include/libfirm/adt/hashptr.h
index 043ba5b63..03dd1087a 100644
--- a/include/libfirm/adt/hashptr.h
+++ b/include/libfirm/adt/hashptr.h
@@ -27,13 +27,13 @@
 #define FIRM_ADT_HASHPTR_H
 
 #include "firm_config.h"
+#include "compiler.h"
 
 #define _FIRM_FNV_OFFSET_BASIS 2166136261U
 #define _FIRM_FNV_FNV_PRIME 16777619U
 
 /* Computing x * _FIRM_FNV_FNV_PRIME */
-#define _FIRM_FNV_TIMES_PRIME(x) \
-  (((x) << 24) + ((x) << 8) + ((x) << 7) + ((x) << 4) + ((x) << 1) + 1)
+#define _FIRM_FNV_TIMES_PRIME(x) ((x) * _FIRM_FNV_FNV_PRIME)
 
 static INLINE unsigned firm_fnv_hash(const unsigned char *data, unsigned bytes)
 {
@@ -48,6 +48,19 @@ static INLINE unsigned firm_fnv_hash(const unsigned char *data, unsigned bytes)
 	return hash;
 }
 
+static INLINE unsigned firm_fnv_hash_str(const char *data)
+{
+	unsigned i;
+	unsigned hash = _FIRM_FNV_OFFSET_BASIS;
+
+	for(i = 0; data[i] != '\0'; ++i) {
+		hash = _FIRM_FNV_TIMES_PRIME(hash);
+		hash ^= data[i];
+	}
+
+	return hash;
+}
+
 /**
  * hash a pointer value: Pointer addresses are mostly aligned to 4
  * or 8 bytes. So we remove the lowest 3 bits