diff options
Diffstat (limited to 'src/liblzma/check/crc32_x86.s')
| -rw-r--r-- | src/liblzma/check/crc32_x86.s | 217 |
1 files changed, 0 insertions, 217 deletions
diff --git a/src/liblzma/check/crc32_x86.s b/src/liblzma/check/crc32_x86.s deleted file mode 100644 index f1ae7f76..00000000 --- a/src/liblzma/check/crc32_x86.s +++ /dev/null @@ -1,217 +0,0 @@ -/* - * Speed-optimized CRC32 using slicing-by-eight algorithm - * Instruction set: i386 - * Optimized for: i686 - * - * This code has been put into the public domain by its authors: - * Original code by Igor Pavlov <http://7-zip.org/> - * Position-independent version by Lasse Collin <lasse.collin@tukaani.org> - * - * This code needs lzma_crc32_table, which can be created using the - * following C code: - -uint32_t lzma_crc32_table[8][256]; - -void -init_table(void) -{ - // IEEE-802.3 (CRC32) - static const uint32_t poly32 = UINT32_C(0xEDB88320); - - // Castagnoli (CRC32C) - // static const uint32_t poly32 = UINT32_C(0x82F63B78); - - // Koopman - // static const uint32_t poly32 = UINT32_C(0xEB31D82E); - - for (size_t s = 0; s < 8; ++s) { - for (size_t b = 0; b < 256; ++b) { - uint32_t r = s == 0 ? b : lzma_crc32_table[s - 1][b]; - - for (size_t i = 0; i < 8; ++i) { - if (r & 1) - r = (r >> 1) ^ poly32; - else - r >>= 1; - } - - lzma_crc32_table[s][b] = r; - } - } -} - - * The prototype of the CRC32 function: - * extern uint32_t lzma_crc32(const uint8_t *buf, size_t size, uint32_t crc); - */ - - .text - .globl lzma_crc32 - .type lzma_crc32, @function - - .align 16 -lzma_crc32: - /* - * Register usage: - * %eax crc - * %esi buf - * %edi size or buf + size - * %ebx lzma_crc32_table - * %ebp Table index - * %ecx Temporary - * %edx Temporary - */ - pushl %ebx - pushl %esi - pushl %edi - pushl %ebp - movl 0x14(%esp), %esi /* buf */ - movl 0x18(%esp), %edi /* size */ - movl 0x1C(%esp), %eax /* crc */ - - /* - * Store the address of lzma_crc32_table to %ebx. This is needed to - * get position-independent code (PIC). - */ - call .L_PIC -.L_PIC: - popl %ebx - addl $_GLOBAL_OFFSET_TABLE_+[.-.L_PIC], %ebx - movl lzma_crc32_table@GOT(%ebx), %ebx - - /* Complement the initial value. */ - notl %eax - - .align 16 -.L_align: - /* - * Check if there is enough input to use slicing-by-eight. - * We need 16 bytes, because the loop pre-reads eight bytes. - */ - cmpl $16, %edi - jl .L_rest - - /* Check if we have reached alignment of eight bytes. */ - testl $7, %esi - jz .L_slice - - /* Calculate CRC of the next input byte. */ - movzbl (%esi), %ebp - incl %esi - movzbl %al, %ecx - xorl %ecx, %ebp - shrl $8, %eax - xorl (%ebx, %ebp, 4), %eax - decl %edi - jmp .L_align - - .align 4 -.L_slice: - /* - * If we get here, there's at least 16 bytes of aligned input - * available. Make %edi multiple of eight bytes. Store the possible - * remainder over the "size" variable in the argument stack. - */ - movl %edi, 0x18(%esp) - andl $-8, %edi - subl %edi, 0x18(%esp) - - /* - * Let %edi be buf + size - 8 while running the main loop. This way - * we can compare for equality to determine when exit the loop. - */ - addl %esi, %edi - subl $8, %edi - - /* Read in the first eight aligned bytes. */ - xorl (%esi), %eax - movl 4(%esi), %ecx - movzbl %cl, %ebp - -.L_loop: - movl 0x0C00(%ebx, %ebp, 4), %edx - movzbl %ch, %ebp - xorl 0x0800(%ebx, %ebp, 4), %edx - shrl $16, %ecx - xorl 8(%esi), %edx - movzbl %cl, %ebp - xorl 0x0400(%ebx, %ebp, 4), %edx - movzbl %ch, %ebp - xorl (%ebx, %ebp, 4), %edx - movzbl %al, %ebp - - /* - * Read the next four bytes, for which the CRC is calculated - * on the next interation of the loop. - */ - movl 12(%esi), %ecx - - xorl 0x1C00(%ebx, %ebp, 4), %edx - movzbl %ah, %ebp - shrl $16, %eax - xorl 0x1800(%ebx, %ebp, 4), %edx - movzbl %ah, %ebp - movzbl %al, %eax - movl 0x1400(%ebx, %eax, 4), %eax - addl $8, %esi - xorl %edx, %eax - xorl 0x1000(%ebx, %ebp, 4), %eax - - /* Check for end of aligned input. */ - cmpl %edi, %esi - movzbl %cl, %ebp - jne .L_loop - - /* - * Process the remaining eight bytes, which we have already - * copied to %ecx and %edx. - */ - movl 0x0C00(%ebx, %ebp, 4), %edx - movzbl %ch, %ebp - xorl 0x0800(%ebx, %ebp, 4), %edx - shrl $16, %ecx - movzbl %cl, %ebp - xorl 0x0400(%ebx, %ebp, 4), %edx - movzbl %ch, %ebp - xorl (%ebx, %ebp, 4), %edx - movzbl %al, %ebp - - xorl 0x1C00(%ebx, %ebp, 4), %edx - movzbl %ah, %ebp - shrl $16, %eax - xorl 0x1800(%ebx, %ebp, 4), %edx - movzbl %ah, %ebp - movzbl %al, %eax - movl 0x1400(%ebx, %eax, 4), %eax - addl $8, %esi - xorl %edx, %eax - xorl 0x1000(%ebx, %ebp, 4), %eax - - /* Copy the number of remaining bytes to %edi. */ - movl 0x18(%esp), %edi - -.L_rest: - /* Check for end of input. */ - testl %edi, %edi - jz .L_return - - /* Calculate CRC of the next input byte. */ - movzbl (%esi), %ebp - incl %esi - movzbl %al, %ecx - xorl %ecx, %ebp - shrl $8, %eax - xorl (%ebx, %ebp, 4), %eax - decl %edi - jmp .L_rest - -.L_return: - /* Complement the final value. */ - notl %eax - - popl %ebp - popl %edi - popl %esi - popl %ebx - ret - - .size lzma_crc32, .-lzma_crc32 |