45 lines
1.6 KiB
Text
45 lines
1.6 KiB
Text
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Directory overview:
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===================
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As writing portable assembler sources supporting different operating
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systems, compilers and assemblers has proven to be extremely painful,
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the assembler sources have been converted into a more portable `db'
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format. Use these whenever possible.
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src_gas sources converted for portable gcc/gas syntax
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src_masm sources converted for portable masm/tasm/wasm syntax
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src_nasm sources converted for portable nasm syntax
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src assembler sources (you need the OpenSource nasm assembler)
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obj pre-assembled object files
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Also look `src_XXX/all/asm_all.asm' which contains all assembler
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functions conveniently arranged into a single file.
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Notes:
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======
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- The assembler sources are designed for a flat 32-bit memory model
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running in protected mode - they should work with all i386
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32-bit compilers around.
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- All functions expect a `cdecl' (C stack based) calling convention.
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The function return value will be placed into `eax'.
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All other registers are preserved.
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- Prototypes for the assembler functions can be found in <lzo/lzo_asm.h>.
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- For reasons of speed all fast assembler decompressors (having `_fast'
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in their name) can access (write to) up to 3 bytes past the end of
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the decompressed (output) block. Data past the end of the compressed
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(input) block is never accessed (read from).
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[ technical note: because data is transferred in 32-bit units ]
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- Finally you should test if the assembler versions are actually faster
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than the C version on your machine - some compilers can do a very good
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optimization job, and they also can optimize the code for a specific
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processor type.
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