hopefully better macros for building on x86

1 files changed, 61 insertions, 43 deletions

diff --git a/stadtx_hash.h b/stadtx_hash.h
index db6c406583..a54af2e590 100644
--- a/stadtx_hash.h
+++ b/stadtx_hash.h
@@ -5,14 +5,6 @@
 #define DEBUG_STADTX_HASH 0
 #endif
 
-
-#ifndef ROTL64
-#define _ROTL_SIZED(x,r,s) ( ((x) << (r)) | ((x) >> ((s) - (r))) )
-#define _ROTR_SIZED(x,r,s) ( ((x) << ((s) - (r))) | ((x) >> (r)) )
-#define ROTL64(x,r) _ROTL_SIZED(x,r,64)
-#define ROTR64(x,r) _ROTR_SIZED(x,r,64)
-#endif
-
 #ifndef PERL_SEEN_HV_FUNC_H
 
 #if !defined(U64)
@@ -35,6 +27,7 @@
 #ifndef STRLEN
 #define STRLEN int
 #endif
+
 #endif
 
 #ifndef STADTX_STATIC_INLINE
@@ -51,47 +44,72 @@
 #endif
 
 #ifndef STADTX_ALLOW_UNALIGNED_AND_LITTLE_ENDIAN
+/* STADTX_ALLOW_UNALIGNED_AND_LITTLE_ENDIAN only matters if nothing has defined U8TO64_LE etc,
+ * and when built with Perl these should be defined before this file is loaded.
+ */
+#ifdef U32_ALIGNMENT_REQUIRED
+#define STADTX_ALLOW_UNALIGNED_AND_LITTLE_ENDIAN 0
+#else
 #define STADTX_ALLOW_UNALIGNED_AND_LITTLE_ENDIAN 1
 #endif
+#endif
+
+#ifndef U8TO64_LE
+#if STADTX_ALLOW_UNALIGNED_AND_LITTLE_ENDIAN
+#define U8TO64_LE(ptr)  (*((const U64 *)(ptr)))
+#else
+#define U8TO64_LE(ptr)  (\
+    (U64)(ptr)[7] << 56 | \
+    (U64)(ptr)[6] << 48 | \
+    (U64)(ptr)[5] << 40 | \
+    (U64)(ptr)[4] << 32 | \
+    (U64)(ptr)[3] << 24 | \
+    (U64)(ptr)[2] << 16 | \
+    (U64)(ptr)[1] << 8  | \
+    (U64)(ptr)[0]         \
+)
+#endif
+#endif
+
+#ifndef U8TO32_LE
+#if STADTX_ALLOW_UNALIGNED_AND_LITTLE_ENDIAN
+#define U8TO32_LE(ptr)  (*((const U32 *)(ptr)))
+#else
+#define U8TO32_LE(ptr)  (\
+    (U32)(ptr)[3] << 24 | \
+    (U32)(ptr)[2] << 16 | \
+    (U32)(ptr)[1] << 8  | \
+    (U32)(ptr)[0]         \
+)
+#endif
+#endif
 
+#ifndef U8TO16_LE
 #if STADTX_ALLOW_UNALIGNED_AND_LITTLE_ENDIAN
-  #ifndef U8TO64_LE
-    #define U8TO64_LE(ptr)  (*((const U64 *)(ptr)))
-  #endif
-  #ifndef U8TO32_LE
-    #define U8TO32_LE(ptr)  (*((const U32 *)(ptr)))
-  #endif
-  #ifndef U8TO16_LE
-    #define U8TO16_LE(ptr)  (*((const U16 *)(ptr)))
-  #endif
+#define U8TO16_LE(ptr)  (*((const U16 *)(ptr)))
 #else
-  #ifndef U8TO64_LE
-    #define U8TO64_LE(ptr)  (\
-        (U64)(ptr)[7] << 56 | \
-        (U64)(ptr)[6] << 48 | \
-        (U64)(ptr)[5] << 40 | \
-        (U64)(ptr)[4] << 32 | \
-        (U64)(ptr)[3] << 24 | \
-        (U64)(ptr)[2] << 16 | \
-        (U64)(ptr)[1] << 8  | \
-        (U64)(ptr)[0]         \
-    )
-  #endif
-  #ifndef U8TO32_LE
-    #define U8TO32_LE(ptr)  (\
-        (U32)(ptr)[3] << 24 | \
-        (U32)(ptr)[2] << 16 | \
-        (U32)(ptr)[1] << 8  | \
-        (U32)(ptr)[0]         \
-    )
-  #endif
-  #ifndef U8TO16_LE
-    #define U8TO16_LE(ptr)  (\
-        (U16)(ptr)[1] << 8  | \
-        (U16)(ptr)[0]         \
-    )
-  #endif
+#define U8TO16_LE(ptr)  (\
+    (U16)(ptr)[1] << 8  | \
+    (U16)(ptr)[0]         \
+)
 #endif
+#endif
+
+/* Find best way to ROTL32/ROTL64 */
+#if defined(_MSC_VER)
+  #include <stdlib.h>  /* Microsoft put _rotl declaration in here */
+  #define ROTL32(x,r)  _rotl(x,r)
+  #define ROTR32(x,r)  _rotr(x,r)
+  #define ROTL64(x,r)  _rotl64(x,r)
+  #define ROTR64(x,r)  _rotr64(x,r)
+#else
+  /* gcc recognises this code and generates a rotate instruction for CPUs with one */
+  #define ROTL32(x,r)  (((U32)(x) << (r)) | ((U32)(x) >> (32 - (r))))
+  #define ROTR32(x,r)  (((U32)(x) << (32 - (r))) | ((U32)(x) >> (r)))
+  #define ROTL64(x,r)  ( ( (U64)(x) << (r) ) | ( (U64)(x) >> ( 64 - (r) ) ) )
+  #define ROTR64(x,r)  ( ( (U64)(x) << ( 64 - (r) ) ) | ( (U64)(x) >> (r) ) )
+#endif
+
 
 /* do a marsaglia xor-shift permutation followed by a
  * multiply by a prime (presumably large) and another