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-rw-r--r--src/liblzma/check/crc64_x86.s203
1 files changed, 0 insertions, 203 deletions
diff --git a/src/liblzma/check/crc64_x86.s b/src/liblzma/check/crc64_x86.s
deleted file mode 100644
index 7ad3d889..00000000
--- a/src/liblzma/check/crc64_x86.s
+++ /dev/null
@@ -1,203 +0,0 @@
-/*
- * Speed-optimized CRC64 using slicing-by-four algorithm
- * Instruction set: i386
- * Optimized for: i686
- *
- * This code has been put into the public domain by its authors:
- * Igor Pavlov <http://7-zip.org/>
- * Lasse Collin <lasse.collin@tukaani.org>
- *
- * This code needs lzma_crc64_table, which can be created using the
- * following C code:
-
-uint64_t lzma_crc64_table[4][256];
-
-void
-init_table(void)
-{
- static const uint64_t poly64 = UINT64_C(0xC96C5795D7870F42);
-
- for (size_t s = 0; s < 4; ++s) {
- for (size_t b = 0; b < 256; ++b) {
- uint64_t r = s == 0 ? b : lzma_crc64_table[s - 1][b];
-
- for (size_t i = 0; i < 8; ++i) {
- if (r & 1)
- r = (r >> 1) ^ poly64;
- else
- r >>= 1;
- }
-
- lzma_crc64_table[s][b] = r;
- }
- }
-}
-
- * The prototype of the CRC64 function:
- * extern uint64_t lzma_crc64(const uint8_t *buf, size_t size, uint64_t crc);
- */
-
- .text
- .globl lzma_crc64
- .type lzma_crc64, @function
-
- .align 16
-lzma_crc64:
- /*
- * Register usage:
- * %eax crc LSB
- * %edx crc MSB
- * %esi buf
- * %edi size or buf + size
- * %ebx lzma_crc64_table
- * %ebp Table index
- * %ecx Temporary
- */
- pushl %ebx
- pushl %esi
- pushl %edi
- pushl %ebp
- movl 0x14(%esp), %esi /* buf */
- movl 0x18(%esp), %edi /* size */
- movl 0x1C(%esp), %eax /* crc LSB */
- movl 0x20(%esp), %edx /* crc MSB */
-
- /*
- * Store the address of lzma_crc64_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_crc64_table@GOT(%ebx), %ebx
-
- /* Complement the initial value. */
- notl %eax
- notl %edx
-
-.L_align:
- /*
- * Check if there is enough input to use slicing-by-four.
- * We need eight bytes, because the loop pre-reads four bytes.
- */
- cmpl $8, %edi
- jl .L_rest
-
- /* Check if we have reached alignment of four bytes. */
- testl $3, %esi
- jz .L_slice
-
- /* Calculate CRC of the next input byte. */
- movzbl (%esi), %ebp
- incl %esi
- movzbl %al, %ecx
- xorl %ecx, %ebp
- shrdl $8, %edx, %eax
- xorl (%ebx, %ebp, 8), %eax
- shrl $8, %edx
- xorl 4(%ebx, %ebp, 8), %edx
- decl %edi
- jmp .L_align
-
-.L_slice:
- /*
- * If we get here, there's at least eight bytes of aligned input
- * available. Make %edi multiple of four bytes. Store the possible
- * remainder over the "size" variable in the argument stack.
- */
- movl %edi, 0x18(%esp)
- andl $-4, %edi
- subl %edi, 0x18(%esp)
-
- /*
- * Let %edi be buf + size - 4 while running the main loop. This way
- * we can compare for equality to determine when exit the loop.
- */
- addl %esi, %edi
- subl $4, %edi
-
- /* Read in the first four aligned bytes. */
- movl (%esi), %ecx
-
-.L_loop:
- xorl %eax, %ecx
- movzbl %cl, %ebp
- movl 0x1800(%ebx, %ebp, 8), %eax
- xorl %edx, %eax
- movl 0x1804(%ebx, %ebp, 8), %edx
- movzbl %ch, %ebp
- xorl 0x1000(%ebx, %ebp, 8), %eax
- xorl 0x1004(%ebx, %ebp, 8), %edx
- shrl $16, %ecx
- movzbl %cl, %ebp
- xorl 0x0800(%ebx, %ebp, 8), %eax
- xorl 0x0804(%ebx, %ebp, 8), %edx
- movzbl %ch, %ebp
- addl $4, %esi
- xorl (%ebx, %ebp, 8), %eax
- xorl 4(%ebx, %ebp, 8), %edx
-
- /* Check for end of aligned input. */
- cmpl %edi, %esi
-
- /*
- * Copy the next input byte to %ecx. It is slightly faster to
- * read it here than at the top of the loop.
- */
- movl (%esi), %ecx
- jl .L_loop
-
- /*
- * Process the remaining four bytes, which we have already
- * copied to %ecx.
- */
- xorl %eax, %ecx
- movzbl %cl, %ebp
- movl 0x1800(%ebx, %ebp, 8), %eax
- xorl %edx, %eax
- movl 0x1804(%ebx, %ebp, 8), %edx
- movzbl %ch, %ebp
- xorl 0x1000(%ebx, %ebp, 8), %eax
- xorl 0x1004(%ebx, %ebp, 8), %edx
- shrl $16, %ecx
- movzbl %cl, %ebp
- xorl 0x0800(%ebx, %ebp, 8), %eax
- xorl 0x0804(%ebx, %ebp, 8), %edx
- movzbl %ch, %ebp
- addl $4, %esi
- xorl (%ebx, %ebp, 8), %eax
- xorl 4(%ebx, %ebp, 8), %edx
-
- /* 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
- shrdl $8, %edx, %eax
- xorl (%ebx, %ebp, 8), %eax
- shrl $8, %edx
- xorl 4(%ebx, %ebp, 8), %edx
- decl %edi
- jmp .L_rest
-
-.L_return:
- /* Complement the final value. */
- notl %eax
- notl %edx
-
- popl %ebp
- popl %edi
- popl %esi
- popl %ebx
- ret
-
- .size lzma_crc64, .-lzma_crc64