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lz4.c : changed a tuning parameter name to MEMORY_USAGE, to better reflect its impact

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Makefile : default produces native binary, all produce native & 32-bits binaries


git-svn-id: https://lz4.googlecode.com/svn/trunk@70 650e7d94-2a16-8b24-b05c-7c0b3f6821cd
This commit is contained in:
yann.collet.73@gmail.com 2012-07-24 17:12:23 +00:00
parent d9ef5117f6
commit cfbace25d7
2 changed files with 12 additions and 10 deletions
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4
Makefile
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@ -8,7 +8,9 @@ else
OUTPUT = LZ4Demo.exe
endif
all: lz4demo
default: lz4demo
all: lz4demo lz4demo32
lz4demo: lz4.c lz4.h lz4hc.c lz4hc.h bench.c lz4demo.c
gcc -O3 -I. -std=c99 -Wall -W -Wundef -Wno-implicit-function-declaration lz4hc.c lz4.c bench.c lz4demo.c -o $(OUTPUT)

18
lz4.c
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@ -34,12 +34,12 @@
//**************************************
// Tuning parameters
//**************************************
// COMPRESSIONLEVEL :
// Increasing this value improves compression ratio
// Lowering this value reduces memory usage
// Reduced memory usage typically improves speed, due to cache effect (ex : L1 32KB for Intel, L1 64KB for AMD)
// Memory usage formula : N->2^(N+2) Bytes (examples : 12 -> 16KB ; 17 -> 512KB)
#define COMPRESSIONLEVEL 12
// MEMORY_USAGE :
// Memory usage formula : N->2^N Bytes (examples : 10 -> 1KB; 12 -> 4KB ; 16 -> 64KB; 20 -> 1MB; etc.)
// Increasing memory usage improves compression ratio
// Reduced memory usage can improve speed, due to cache effect
// Default value is 14, for 16KB, which nicely fits into Intel x86 L1 cache
#define MEMORY_USAGE 14
// NOTCOMPRESSIBLE_CONFIRMATION :
// Decreasing this value will make the algorithm skip faster data segments considered "incompressible"
@ -57,8 +57,8 @@
#define LZ4_COMPRESSMIN 0
// BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE :
// This will provide a boost to performance for big endian cpu, but the resulting compressed stream will be incompatible with little-endian CPU.
// You can set this option to 1 in situations where data will stay within closed environment
// This will provide a small boost to performance for big endian cpu, but the resulting compressed stream will be incompatible with little-endian CPU.
// You can set this option to 1 in situations where data will remain within closed environment
// This option is useless on Little_Endian CPU (such as x86)
//#define BIG_ENDIAN_NATIVE_BUT_INCOMPATIBLE 1
@ -181,7 +181,7 @@ typedef struct _U64_S { U64 v; } U64_S;
//**************************************
#define MINMATCH 4
#define HASH_LOG COMPRESSIONLEVEL
#define HASH_LOG (MEMORY_USAGE-2)
#define HASHTABLESIZE (1 << HASH_LOG)
#define HASH_MASK (HASHTABLESIZE - 1)