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author Vas Crabb <vas@vastheman.com>2023-05-04 02:41:16 +1000
committer Vas Crabb <vas@vastheman.com>2023-05-04 02:41:16 +1000
commita504bde3a7462b54fafd5cfc2f52e58d0f3218e1 (patch)
tree8b3108d572b1a0873a6cdbb4e8af1f17179545c3 /3rdparty/lzma/C/LzHash.h
parentbefb9bf4a8cfdb2b693a32e32535b5eac522c5d8 (diff)
3rdparty/lzma: Updated to LZMA SDK version 22.01
Diffstat (limited to '3rdparty/lzma/C/LzHash.h')
-rw-r--r--3rdparty/lzma/C/LzHash.h67
1 files changed, 22 insertions, 45 deletions
diff --git a/3rdparty/lzma/C/LzHash.h b/3rdparty/lzma/C/LzHash.h
index e7c942303dd..77b898cfab5 100644
--- a/3rdparty/lzma/C/LzHash.h
+++ b/3rdparty/lzma/C/LzHash.h
@@ -1,57 +1,34 @@
/* LzHash.h -- HASH functions for LZ algorithms
-2015-04-12 : Igor Pavlov : Public domain */
+2019-10-30 : Igor Pavlov : Public domain */
#ifndef __LZ_HASH_H
#define __LZ_HASH_H
+/*
+ (kHash2Size >= (1 << 8)) : Required
+ (kHash3Size >= (1 << 16)) : Required
+*/
+
#define kHash2Size (1 << 10)
#define kHash3Size (1 << 16)
-#define kHash4Size (1 << 20)
+// #define kHash4Size (1 << 20)
#define kFix3HashSize (kHash2Size)
#define kFix4HashSize (kHash2Size + kHash3Size)
-#define kFix5HashSize (kHash2Size + kHash3Size + kHash4Size)
-
-#define HASH2_CALC hv = cur[0] | ((UInt32)cur[1] << 8);
-
-#define HASH3_CALC { \
- UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
- h2 = temp & (kHash2Size - 1); \
- hv = (temp ^ ((UInt32)cur[2] << 8)) & p->hashMask; }
-
-#define HASH4_CALC { \
- UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
- h2 = temp & (kHash2Size - 1); \
- temp ^= ((UInt32)cur[2] << 8); \
- h3 = temp & (kHash3Size - 1); \
- hv = (temp ^ (p->crc[cur[3]] << 5)) & p->hashMask; }
-
-#define HASH5_CALC { \
- UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
- h2 = temp & (kHash2Size - 1); \
- temp ^= ((UInt32)cur[2] << 8); \
- h3 = temp & (kHash3Size - 1); \
- temp ^= (p->crc[cur[3]] << 5); \
- h4 = temp & (kHash4Size - 1); \
- hv = (temp ^ (p->crc[cur[4]] << 3)) & p->hashMask; }
-
-/* #define HASH_ZIP_CALC hv = ((cur[0] | ((UInt32)cur[1] << 8)) ^ p->crc[cur[2]]) & 0xFFFF; */
-#define HASH_ZIP_CALC hv = ((cur[2] | ((UInt32)cur[0] << 8)) ^ p->crc[cur[1]]) & 0xFFFF;
-
-
-#define MT_HASH2_CALC \
- h2 = (p->crc[cur[0]] ^ cur[1]) & (kHash2Size - 1);
-
-#define MT_HASH3_CALC { \
- UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
- h2 = temp & (kHash2Size - 1); \
- h3 = (temp ^ ((UInt32)cur[2] << 8)) & (kHash3Size - 1); }
-
-#define MT_HASH4_CALC { \
- UInt32 temp = p->crc[cur[0]] ^ cur[1]; \
- h2 = temp & (kHash2Size - 1); \
- temp ^= ((UInt32)cur[2] << 8); \
- h3 = temp & (kHash3Size - 1); \
- h4 = (temp ^ (p->crc[cur[3]] << 5)) & (kHash4Size - 1); }
+// #define kFix5HashSize (kHash2Size + kHash3Size + kHash4Size)
+
+/*
+ We use up to 3 crc values for hash:
+ crc0
+ crc1 << Shift_1
+ crc2 << Shift_2
+ (Shift_1 = 5) and (Shift_2 = 10) is good tradeoff.
+ Small values for Shift are not good for collision rate.
+ Big value for Shift_2 increases the minimum size
+ of hash table, that will be slow for small files.
+*/
+
+#define kLzHash_CrcShift_1 5
+#define kLzHash_CrcShift_2 10
#endif