Add an unpatched version of xz, XZ Utils, to /trunk/deps/third_party

xz/src/liblzma/check/crc32_x86.S

+/*
+ * Speed-optimized CRC32 using slicing-by-eight algorithm
+ *
+ * This uses only i386 instructions, but it is optimized for i686 and later
+ * (including e.g. Pentium II/III/IV, Athlon XP, and Core 2). For i586
+ * (e.g. Pentium), slicing-by-four would be better, and even the C version
+ * of slicing-by-eight built with gcc -march=i586 tends to be a little bit
+ * better than this. Very few probably run this code on i586 or older x86
+ * so this shouldn't be a problem in practice.
+ *
+ * Authors: Igor Pavlov (original version)
+ *          Lasse Collin (AT&T syntax, PIC support, better portability)
+ *
+ * This file has been put into the public domain.
+ * You can do whatever you want with this file.
+ *
+ * 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
+        static const uint32_t poly32 = UINT32_C(0xEDB88320);
+
+        // Castagnoli
+        // 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);
+ */
+
+/*
+ * On some systems, the functions need to be prefixed. The prefix is
+ * usually an underscore.
+ */
+#ifndef __USER_LABEL_PREFIX__
+#       define __USER_LABEL_PREFIX__
+#endif
+#define MAKE_SYM_CAT(prefix, sym) prefix ## sym
+#define MAKE_SYM(prefix, sym) MAKE_SYM_CAT(prefix, sym)
+#define LZMA_CRC32 MAKE_SYM(__USER_LABEL_PREFIX__, lzma_crc32)
+#define LZMA_CRC32_TABLE MAKE_SYM(__USER_LABEL_PREFIX__, lzma_crc32_table)
+
+/*
+ * Solaris assembler doesn't have .p2align, and Darwin uses .align
+ * differently than GNU/Linux and Solaris.
+ */
+#if defined(__APPLE__) || defined(__MSDOS__)
+#       define ALIGN(pow2, abs) .align pow2
+#else
+#       define ALIGN(pow2, abs) .align abs
+#endif
+
+        .text
+        .globl  LZMA_CRC32
+
+#if !defined(__APPLE__) && !defined(_WIN32) && !defined(__CYGWIN__) \
+                && !defined(__MSDOS__)
+        .type   LZMA_CRC32, @function
+#endif
+
+        ALIGN(4, 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).
+         *
+         * The PIC macro is defined by libtool, while __PIC__ is defined
+         * by GCC but only on some systems. Testing for both makes it simpler
+         * to test this code without libtool, and keeps the code working also
+         * when built with libtool but using something else than GCC.
+         *
+         * I understood that libtool may define PIC on Windows even though
+         * the code in Windows DLLs is not PIC in sense that it is in ELF
+         * binaries, so we need a separate check to always use the non-PIC
+         * code on Windows.
+         */
+#if (!defined(PIC) && !defined(__PIC__)) \
+                || (defined(_WIN32) || defined(__CYGWIN__))
+        /* Not PIC */
+        movl    $ LZMA_CRC32_TABLE, %ebx
+#elif defined(__APPLE__)
+        /* Mach-O */
+        call    .L_get_pc
+.L_pic:
+        leal    .L_lzma_crc32_table$non_lazy_ptr-.L_pic(%ebx), %ebx
+        movl    (%ebx), %ebx
+#else
+        /* ELF */
+        call    .L_get_pc
+        addl    $_GLOBAL_OFFSET_TABLE_, %ebx
+        movl    LZMA_CRC32_TABLE@GOT(%ebx), %ebx
+#endif
+
+        /* Complement the initial value. */
+        notl    %eax
+
+        ALIGN(4, 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
+        jb      .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(2, 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    $8, %eax
+        xorl    (%ebx, %ebp, 4), %eax
+        decl    %edi
+        jmp     .L_rest
+
+.L_return:
+        /* Complement the final value. */
+        notl    %eax
+
+        popl    %ebp
+        popl    %edi
+        popl    %esi
+        popl    %ebx
+        ret
+
+#if defined(PIC) || defined(__PIC__)
+        ALIGN(4, 16)
+.L_get_pc:
+        movl    (%esp), %ebx
+        ret
+#endif
+
+#if defined(__APPLE__) && (defined(PIC) || defined(__PIC__))
+        /* Mach-O PIC */
+        .section __IMPORT,__pointers,non_lazy_symbol_pointers
+.L_lzma_crc32_table$non_lazy_ptr:
+        .indirect_symbol LZMA_CRC32_TABLE
+        .long 0
+
+#elif defined(_WIN32) || defined(__CYGWIN__)
+#       ifdef DLL_EXPORT
+        /* This is equivalent of __declspec(dllexport). */
+        .section .drectve
+        .ascii " -export:lzma_crc32"
+#       endif
+
+#elif !defined(__MSDOS__)
+        /* ELF */
+        .size   LZMA_CRC32, .-LZMA_CRC32
+#endif
+
+/*
+ * This is needed to support non-executable stack. It's ugly to
+ * use __linux__ here, but I don't know a way to detect when
+ * we are using GNU assembler.
+ */
+#if defined(__ELF__) && defined(__linux__)
+        .section        .note.GNU-stack,"",@progbits
+#endif