[2725] | 1 | /*
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| 2 | * Branch/Call/Jump (BCJ) filter decoders
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| 3 | *
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| 4 | * Authors: Lasse Collin <lasse.collin@tukaani.org>
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| 5 | * Igor Pavlov <http://7-zip.org/>
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| 6 | *
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| 7 | * This file has been put into the public domain.
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| 8 | * You can do whatever you want with this file.
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| 9 | */
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| 10 |
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| 11 | #include "xz_private.h"
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| 12 |
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| 13 | /*
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| 14 | * The rest of the file is inside this ifdef. It makes things a little more
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| 15 | * convenient when building without support for any BCJ filters.
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| 16 | */
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| 17 | #ifdef XZ_DEC_BCJ
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| 18 |
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| 19 | struct xz_dec_bcj {
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| 20 | /* Type of the BCJ filter being used */
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| 21 | enum {
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| 22 | BCJ_X86 = 4, /* x86 or x86-64 */
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| 23 | BCJ_POWERPC = 5, /* Big endian only */
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| 24 | BCJ_IA64 = 6, /* Big or little endian */
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| 25 | BCJ_ARM = 7, /* Little endian only */
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| 26 | BCJ_ARMTHUMB = 8, /* Little endian only */
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| 27 | BCJ_SPARC = 9 /* Big or little endian */
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| 28 | } type;
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| 29 |
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| 30 | /*
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| 31 | * Return value of the next filter in the chain. We need to preserve
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| 32 | * this information across calls, because we must not call the next
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| 33 | * filter anymore once it has returned XZ_STREAM_END.
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| 34 | */
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| 35 | enum xz_ret ret;
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| 36 |
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| 37 | /* True if we are operating in single-call mode. */
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| 38 | bool single_call;
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| 39 |
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| 40 | /*
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| 41 | * Absolute position relative to the beginning of the uncompressed
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| 42 | * data (in a single .xz Block). We care only about the lowest 32
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| 43 | * bits so this doesn't need to be uint64_t even with big files.
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| 44 | */
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| 45 | uint32_t pos;
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| 46 |
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| 47 | /* x86 filter state */
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| 48 | uint32_t x86_prev_mask;
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| 49 |
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| 50 | /* Temporary space to hold the variables from struct xz_buf */
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| 51 | uint8_t *out;
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| 52 | size_t out_pos;
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| 53 | size_t out_size;
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| 54 |
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| 55 | struct {
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| 56 | /* Amount of already filtered data in the beginning of buf */
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| 57 | size_t filtered;
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| 58 |
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| 59 | /* Total amount of data currently stored in buf */
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| 60 | size_t size;
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| 61 |
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| 62 | /*
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| 63 | * Buffer to hold a mix of filtered and unfiltered data. This
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| 64 | * needs to be big enough to hold Alignment + 2 * Look-ahead:
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| 65 | *
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| 66 | * Type Alignment Look-ahead
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| 67 | * x86 1 4
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| 68 | * PowerPC 4 0
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| 69 | * IA-64 16 0
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| 70 | * ARM 4 0
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| 71 | * ARM-Thumb 2 2
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| 72 | * SPARC 4 0
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| 73 | */
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| 74 | uint8_t buf[16];
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| 75 | } temp;
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| 76 | };
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| 77 |
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| 78 | #ifdef XZ_DEC_X86
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| 79 | /*
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| 80 | * This is macro used to test the most significant byte of a memory address
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| 81 | * in an x86 instruction.
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| 82 | */
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| 83 | #define bcj_x86_test_msbyte(b) ((b) == 0x00 || (b) == 0xFF)
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| 84 |
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| 85 | static noinline_for_stack size_t XZ_FUNC bcj_x86(
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| 86 | struct xz_dec_bcj *s, uint8_t *buf, size_t size)
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| 87 | {
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| 88 | static const bool mask_to_allowed_status[8]
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| 89 | = { true, true, true, false, true, false, false, false };
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| 90 |
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| 91 | static const uint8_t mask_to_bit_num[8] = { 0, 1, 2, 2, 3, 3, 3, 3 };
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| 92 |
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| 93 | size_t i;
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| 94 | size_t prev_pos = (size_t)-1;
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| 95 | uint32_t prev_mask = s->x86_prev_mask;
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| 96 | uint32_t src;
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| 97 | uint32_t dest;
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| 98 | uint32_t j;
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| 99 | uint8_t b;
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| 100 |
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| 101 | if (size <= 4)
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| 102 | return 0;
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| 103 |
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| 104 | size -= 4;
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| 105 | for (i = 0; i < size; ++i) {
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| 106 | if ((buf[i] & 0xFE) != 0xE8)
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| 107 | continue;
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| 108 |
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| 109 | prev_pos = i - prev_pos;
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| 110 | if (prev_pos > 3) {
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| 111 | prev_mask = 0;
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| 112 | } else {
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| 113 | prev_mask = (prev_mask << (prev_pos - 1)) & 7;
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| 114 | if (prev_mask != 0) {
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| 115 | b = buf[i + 4 - mask_to_bit_num[prev_mask]];
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| 116 | if (!mask_to_allowed_status[prev_mask]
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| 117 | || bcj_x86_test_msbyte(b)) {
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| 118 | prev_pos = i;
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| 119 | prev_mask = (prev_mask << 1) | 1;
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| 120 | continue;
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| 121 | }
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| 122 | }
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| 123 | }
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| 124 |
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| 125 | prev_pos = i;
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| 126 |
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| 127 | if (bcj_x86_test_msbyte(buf[i + 4])) {
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| 128 | src = get_unaligned_le32(buf + i + 1);
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| 129 | while (true) {
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| 130 | dest = src - (s->pos + (uint32_t)i + 5);
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| 131 | if (prev_mask == 0)
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| 132 | break;
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| 133 |
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| 134 | j = mask_to_bit_num[prev_mask] * 8;
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| 135 | b = (uint8_t)(dest >> (24 - j));
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| 136 | if (!bcj_x86_test_msbyte(b))
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| 137 | break;
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| 138 |
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| 139 | src = dest ^ (((uint32_t)1 << (32 - j)) - 1);
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| 140 | }
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| 141 |
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| 142 | dest &= 0x01FFFFFF;
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| 143 | dest |= (uint32_t)0 - (dest & 0x01000000);
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| 144 | put_unaligned_le32(dest, buf + i + 1);
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| 145 | i += 4;
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| 146 | } else {
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| 147 | prev_mask = (prev_mask << 1) | 1;
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| 148 | }
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| 149 | }
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| 150 |
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| 151 | prev_pos = i - prev_pos;
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| 152 | s->x86_prev_mask = prev_pos > 3 ? 0 : prev_mask << (prev_pos - 1);
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| 153 | return i;
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| 154 | }
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| 155 | #endif
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| 156 |
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| 157 | #ifdef XZ_DEC_POWERPC
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| 158 | static noinline_for_stack size_t XZ_FUNC bcj_powerpc(
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| 159 | struct xz_dec_bcj *s, uint8_t *buf, size_t size)
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| 160 | {
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| 161 | size_t i;
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| 162 | uint32_t instr;
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| 163 |
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| 164 | for (i = 0; i + 4 <= size; i += 4) {
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| 165 | instr = get_unaligned_be32(buf + i);
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| 166 | if ((instr & 0xFC000003) == 0x48000001) {
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| 167 | instr &= 0x03FFFFFC;
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| 168 | instr -= s->pos + (uint32_t)i;
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| 169 | instr &= 0x03FFFFFC;
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| 170 | instr |= 0x48000001;
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| 171 | put_unaligned_be32(instr, buf + i);
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| 172 | }
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| 173 | }
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| 174 |
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| 175 | return i;
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| 176 | }
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| 177 | #endif
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| 178 |
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| 179 | #ifdef XZ_DEC_IA64
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| 180 | static noinline_for_stack size_t XZ_FUNC bcj_ia64(
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| 181 | struct xz_dec_bcj *s, uint8_t *buf, size_t size)
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| 182 | {
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| 183 | static const uint8_t branch_table[32] = {
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| 184 | 0, 0, 0, 0, 0, 0, 0, 0,
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| 185 | 0, 0, 0, 0, 0, 0, 0, 0,
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| 186 | 4, 4, 6, 6, 0, 0, 7, 7,
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| 187 | 4, 4, 0, 0, 4, 4, 0, 0
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| 188 | };
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| 189 |
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| 190 | /*
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| 191 | * The local variables take a little bit stack space, but it's less
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| 192 | * than what LZMA2 decoder takes, so it doesn't make sense to reduce
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| 193 | * stack usage here without doing that for the LZMA2 decoder too.
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| 194 | */
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| 195 |
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| 196 | /* Loop counters */
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| 197 | size_t i;
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| 198 | size_t j;
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| 199 |
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| 200 | /* Instruction slot (0, 1, or 2) in the 128-bit instruction word */
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| 201 | uint32_t slot;
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| 202 |
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| 203 | /* Bitwise offset of the instruction indicated by slot */
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| 204 | uint32_t bit_pos;
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| 205 |
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| 206 | /* bit_pos split into byte and bit parts */
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| 207 | uint32_t byte_pos;
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| 208 | uint32_t bit_res;
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| 209 |
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| 210 | /* Address part of an instruction */
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| 211 | uint32_t addr;
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| 212 |
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| 213 | /* Mask used to detect which instructions to convert */
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| 214 | uint32_t mask;
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| 215 |
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| 216 | /* 41-bit instruction stored somewhere in the lowest 48 bits */
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| 217 | uint64_t instr;
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| 218 |
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| 219 | /* Instruction normalized with bit_res for easier manipulation */
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| 220 | uint64_t norm;
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| 221 |
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| 222 | for (i = 0; i + 16 <= size; i += 16) {
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| 223 | mask = branch_table[buf[i] & 0x1F];
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| 224 | for (slot = 0, bit_pos = 5; slot < 3; ++slot, bit_pos += 41) {
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| 225 | if (((mask >> slot) & 1) == 0)
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| 226 | continue;
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| 227 |
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| 228 | byte_pos = bit_pos >> 3;
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| 229 | bit_res = bit_pos & 7;
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| 230 | instr = 0;
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| 231 | for (j = 0; j < 6; ++j)
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| 232 | instr |= (uint64_t)(buf[i + j + byte_pos])
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| 233 | << (8 * j);
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| 234 |
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| 235 | norm = instr >> bit_res;
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| 236 |
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| 237 | if (((norm >> 37) & 0x0F) == 0x05
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| 238 | && ((norm >> 9) & 0x07) == 0) {
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| 239 | addr = (norm >> 13) & 0x0FFFFF;
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| 240 | addr |= ((uint32_t)(norm >> 36) & 1) << 20;
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| 241 | addr <<= 4;
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| 242 | addr -= s->pos + (uint32_t)i;
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| 243 | addr >>= 4;
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| 244 |
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| 245 | norm &= ~((uint64_t)0x8FFFFF << 13);
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| 246 | norm |= (uint64_t)(addr & 0x0FFFFF) << 13;
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| 247 | norm |= (uint64_t)(addr & 0x100000)
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| 248 | << (36 - 20);
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| 249 |
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| 250 | instr &= (1 << bit_res) - 1;
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| 251 | instr |= norm << bit_res;
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| 252 |
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| 253 | for (j = 0; j < 6; j++)
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| 254 | buf[i + j + byte_pos]
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| 255 | = (uint8_t)(instr >> (8 * j));
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| 256 | }
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| 257 | }
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| 258 | }
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| 259 |
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| 260 | return i;
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| 261 | }
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| 262 | #endif
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| 263 |
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| 264 | #ifdef XZ_DEC_ARM
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| 265 | static noinline_for_stack size_t XZ_FUNC bcj_arm(
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| 266 | struct xz_dec_bcj *s, uint8_t *buf, size_t size)
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| 267 | {
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| 268 | size_t i;
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| 269 | uint32_t addr;
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| 270 |
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| 271 | for (i = 0; i + 4 <= size; i += 4) {
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| 272 | if (buf[i + 3] == 0xEB) {
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| 273 | addr = (uint32_t)buf[i] | ((uint32_t)buf[i + 1] << 8)
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| 274 | | ((uint32_t)buf[i + 2] << 16);
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| 275 | addr <<= 2;
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| 276 | addr -= s->pos + (uint32_t)i + 8;
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| 277 | addr >>= 2;
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| 278 | buf[i] = (uint8_t)addr;
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| 279 | buf[i + 1] = (uint8_t)(addr >> 8);
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| 280 | buf[i + 2] = (uint8_t)(addr >> 16);
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| 281 | }
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| 282 | }
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| 283 |
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| 284 | return i;
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| 285 | }
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| 286 | #endif
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| 287 |
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| 288 | #ifdef XZ_DEC_ARMTHUMB
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| 289 | static noinline_for_stack size_t XZ_FUNC bcj_armthumb(
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| 290 | struct xz_dec_bcj *s, uint8_t *buf, size_t size)
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| 291 | {
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| 292 | size_t i;
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| 293 | uint32_t addr;
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| 294 |
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| 295 | for (i = 0; i + 4 <= size; i += 2) {
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| 296 | if ((buf[i + 1] & 0xF8) == 0xF0
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| 297 | && (buf[i + 3] & 0xF8) == 0xF8) {
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| 298 | addr = (((uint32_t)buf[i + 1] & 0x07) << 19)
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| 299 | | ((uint32_t)buf[i] << 11)
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| 300 | | (((uint32_t)buf[i + 3] & 0x07) << 8)
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| 301 | | (uint32_t)buf[i + 2];
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| 302 | addr <<= 1;
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| 303 | addr -= s->pos + (uint32_t)i + 4;
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| 304 | addr >>= 1;
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| 305 | buf[i + 1] = (uint8_t)(0xF0 | ((addr >> 19) & 0x07));
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| 306 | buf[i] = (uint8_t)(addr >> 11);
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| 307 | buf[i + 3] = (uint8_t)(0xF8 | ((addr >> 8) & 0x07));
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| 308 | buf[i + 2] = (uint8_t)addr;
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| 309 | i += 2;
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| 310 | }
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| 311 | }
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| 312 |
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| 313 | return i;
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| 314 | }
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| 315 | #endif
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| 316 |
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| 317 | #ifdef XZ_DEC_SPARC
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| 318 | static noinline_for_stack size_t XZ_FUNC bcj_sparc(
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| 319 | struct xz_dec_bcj *s, uint8_t *buf, size_t size)
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| 320 | {
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| 321 | size_t i;
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| 322 | uint32_t instr;
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| 323 |
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| 324 | for (i = 0; i + 4 <= size; i += 4) {
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| 325 | instr = get_unaligned_be32(buf + i);
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| 326 | if ((instr >> 22) == 0x100 || (instr >> 22) == 0x1FF) {
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| 327 | instr <<= 2;
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| 328 | instr -= s->pos + (uint32_t)i;
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| 329 | instr >>= 2;
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| 330 | instr = ((uint32_t)0x40000000 - (instr & 0x400000))
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| 331 | | 0x40000000 | (instr & 0x3FFFFF);
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| 332 | put_unaligned_be32(instr, buf + i);
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| 333 | }
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| 334 | }
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| 335 |
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| 336 | return i;
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| 337 | }
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| 338 | #endif
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| 339 |
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| 340 | /*
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| 341 | * Apply the selected BCJ filter. Update *pos and s->pos to match the amount
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| 342 | * of data that got filtered.
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| 343 | *
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| 344 | * NOTE: This is implemented as a switch statement to avoid using function
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| 345 | * pointers, which could be problematic in the kernel boot code, which must
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| 346 | * avoid pointers to static data (at least on x86).
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| 347 | */
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| 348 | static void XZ_FUNC bcj_apply(struct xz_dec_bcj *s,
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| 349 | uint8_t *buf, size_t *pos, size_t size)
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| 350 | {
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| 351 | size_t filtered;
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| 352 |
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| 353 | buf += *pos;
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| 354 | size -= *pos;
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| 355 |
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| 356 | switch (s->type) {
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| 357 | #ifdef XZ_DEC_X86
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| 358 | case BCJ_X86:
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| 359 | filtered = bcj_x86(s, buf, size);
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| 360 | break;
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| 361 | #endif
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| 362 | #ifdef XZ_DEC_POWERPC
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| 363 | case BCJ_POWERPC:
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| 364 | filtered = bcj_powerpc(s, buf, size);
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| 365 | break;
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| 366 | #endif
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| 367 | #ifdef XZ_DEC_IA64
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| 368 | case BCJ_IA64:
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| 369 | filtered = bcj_ia64(s, buf, size);
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| 370 | break;
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| 371 | #endif
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| 372 | #ifdef XZ_DEC_ARM
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| 373 | case BCJ_ARM:
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| 374 | filtered = bcj_arm(s, buf, size);
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| 375 | break;
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| 376 | #endif
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| 377 | #ifdef XZ_DEC_ARMTHUMB
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| 378 | case BCJ_ARMTHUMB:
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| 379 | filtered = bcj_armthumb(s, buf, size);
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| 380 | break;
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| 381 | #endif
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| 382 | #ifdef XZ_DEC_SPARC
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| 383 | case BCJ_SPARC:
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| 384 | filtered = bcj_sparc(s, buf, size);
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| 385 | break;
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| 386 | #endif
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| 387 | default:
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| 388 | /* Never reached but silence compiler warnings. */
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| 389 | filtered = 0;
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| 390 | break;
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| 391 | }
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| 392 |
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| 393 | *pos += filtered;
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| 394 | s->pos += filtered;
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| 395 | }
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| 396 |
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| 397 | /*
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| 398 | * Flush pending filtered data from temp to the output buffer.
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| 399 | * Move the remaining mixture of possibly filtered and unfiltered
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| 400 | * data to the beginning of temp.
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| 401 | */
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| 402 | static void XZ_FUNC bcj_flush(struct xz_dec_bcj *s, struct xz_buf *b)
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| 403 | {
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| 404 | size_t copy_size;
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| 405 |
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| 406 | copy_size = min_t(size_t, s->temp.filtered, b->out_size - b->out_pos);
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| 407 | memcpy(b->out + b->out_pos, s->temp.buf, copy_size);
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| 408 | b->out_pos += copy_size;
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| 409 |
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| 410 | s->temp.filtered -= copy_size;
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| 411 | s->temp.size -= copy_size;
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| 412 | memmove(s->temp.buf, s->temp.buf + copy_size, s->temp.size);
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| 413 | }
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| 414 |
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| 415 | /*
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| 416 | * The BCJ filter functions are primitive in sense that they process the
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| 417 | * data in chunks of 1-16 bytes. To hide this issue, this function does
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| 418 | * some buffering.
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| 419 | */
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| 420 | XZ_EXTERN enum xz_ret XZ_FUNC xz_dec_bcj_run(struct xz_dec_bcj *s,
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| 421 | struct xz_dec_lzma2 *lzma2, struct xz_buf *b)
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| 422 | {
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| 423 | size_t out_start;
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| 424 |
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| 425 | /*
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| 426 | * Flush pending already filtered data to the output buffer. Return
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| 427 | * immediatelly if we couldn't flush everything, or if the next
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| 428 | * filter in the chain had already returned XZ_STREAM_END.
|
---|
| 429 | */
|
---|
| 430 | if (s->temp.filtered > 0) {
|
---|
| 431 | bcj_flush(s, b);
|
---|
| 432 | if (s->temp.filtered > 0)
|
---|
| 433 | return XZ_OK;
|
---|
| 434 |
|
---|
| 435 | if (s->ret == XZ_STREAM_END)
|
---|
| 436 | return XZ_STREAM_END;
|
---|
| 437 | }
|
---|
| 438 |
|
---|
| 439 | /*
|
---|
| 440 | * If we have more output space than what is currently pending in
|
---|
| 441 | * temp, copy the unfiltered data from temp to the output buffer
|
---|
| 442 | * and try to fill the output buffer by decoding more data from the
|
---|
| 443 | * next filter in the chain. Apply the BCJ filter on the new data
|
---|
| 444 | * in the output buffer. If everything cannot be filtered, copy it
|
---|
| 445 | * to temp and rewind the output buffer position accordingly.
|
---|
| 446 | */
|
---|
| 447 | if (s->temp.size < b->out_size - b->out_pos) {
|
---|
| 448 | out_start = b->out_pos;
|
---|
| 449 | memcpy(b->out + b->out_pos, s->temp.buf, s->temp.size);
|
---|
| 450 | b->out_pos += s->temp.size;
|
---|
| 451 |
|
---|
| 452 | s->ret = xz_dec_lzma2_run(lzma2, b);
|
---|
| 453 | if (s->ret != XZ_STREAM_END
|
---|
| 454 | && (s->ret != XZ_OK || s->single_call))
|
---|
| 455 | return s->ret;
|
---|
| 456 |
|
---|
| 457 | bcj_apply(s, b->out, &out_start, b->out_pos);
|
---|
| 458 |
|
---|
| 459 | /*
|
---|
| 460 | * As an exception, if the next filter returned XZ_STREAM_END,
|
---|
| 461 | * we can do that too, since the last few bytes that remain
|
---|
| 462 | * unfiltered are meant to remain unfiltered.
|
---|
| 463 | */
|
---|
| 464 | if (s->ret == XZ_STREAM_END)
|
---|
| 465 | return XZ_STREAM_END;
|
---|
| 466 |
|
---|
| 467 | s->temp.size = b->out_pos - out_start;
|
---|
| 468 | b->out_pos -= s->temp.size;
|
---|
| 469 | memcpy(s->temp.buf, b->out + b->out_pos, s->temp.size);
|
---|
| 470 | }
|
---|
| 471 |
|
---|
| 472 | /*
|
---|
| 473 | * If we have unfiltered data in temp, try to fill by decoding more
|
---|
| 474 | * data from the next filter. Apply the BCJ filter on temp. Then we
|
---|
| 475 | * hopefully can fill the actual output buffer by copying filtered
|
---|
| 476 | * data from temp. A mix of filtered and unfiltered data may be left
|
---|
| 477 | * in temp; it will be taken care on the next call to this function.
|
---|
| 478 | */
|
---|
| 479 | if (s->temp.size > 0) {
|
---|
| 480 | /* Make b->out{,_pos,_size} temporarily point to s->temp. */
|
---|
| 481 | s->out = b->out;
|
---|
| 482 | s->out_pos = b->out_pos;
|
---|
| 483 | s->out_size = b->out_size;
|
---|
| 484 | b->out = s->temp.buf;
|
---|
| 485 | b->out_pos = s->temp.size;
|
---|
| 486 | b->out_size = sizeof(s->temp.buf);
|
---|
| 487 |
|
---|
| 488 | s->ret = xz_dec_lzma2_run(lzma2, b);
|
---|
| 489 |
|
---|
| 490 | s->temp.size = b->out_pos;
|
---|
| 491 | b->out = s->out;
|
---|
| 492 | b->out_pos = s->out_pos;
|
---|
| 493 | b->out_size = s->out_size;
|
---|
| 494 |
|
---|
| 495 | if (s->ret != XZ_OK && s->ret != XZ_STREAM_END)
|
---|
| 496 | return s->ret;
|
---|
| 497 |
|
---|
| 498 | bcj_apply(s, s->temp.buf, &s->temp.filtered, s->temp.size);
|
---|
| 499 |
|
---|
| 500 | /*
|
---|
| 501 | * If the next filter returned XZ_STREAM_END, we mark that
|
---|
| 502 | * everything is filtered, since the last unfiltered bytes
|
---|
| 503 | * of the stream are meant to be left as is.
|
---|
| 504 | */
|
---|
| 505 | if (s->ret == XZ_STREAM_END)
|
---|
| 506 | s->temp.filtered = s->temp.size;
|
---|
| 507 |
|
---|
| 508 | bcj_flush(s, b);
|
---|
| 509 | if (s->temp.filtered > 0)
|
---|
| 510 | return XZ_OK;
|
---|
| 511 | }
|
---|
| 512 |
|
---|
| 513 | return s->ret;
|
---|
| 514 | }
|
---|
| 515 |
|
---|
| 516 | XZ_EXTERN struct xz_dec_bcj * XZ_FUNC xz_dec_bcj_create(bool single_call)
|
---|
| 517 | {
|
---|
| 518 | struct xz_dec_bcj *s = kmalloc(sizeof(*s), GFP_KERNEL);
|
---|
| 519 | if (s != NULL)
|
---|
| 520 | s->single_call = single_call;
|
---|
| 521 |
|
---|
| 522 | return s;
|
---|
| 523 | }
|
---|
| 524 |
|
---|
| 525 | XZ_EXTERN enum xz_ret XZ_FUNC xz_dec_bcj_reset(
|
---|
| 526 | struct xz_dec_bcj *s, uint8_t id)
|
---|
| 527 | {
|
---|
| 528 | switch (id) {
|
---|
| 529 | #ifdef XZ_DEC_X86
|
---|
| 530 | case BCJ_X86:
|
---|
| 531 | #endif
|
---|
| 532 | #ifdef XZ_DEC_POWERPC
|
---|
| 533 | case BCJ_POWERPC:
|
---|
| 534 | #endif
|
---|
| 535 | #ifdef XZ_DEC_IA64
|
---|
| 536 | case BCJ_IA64:
|
---|
| 537 | #endif
|
---|
| 538 | #ifdef XZ_DEC_ARM
|
---|
| 539 | case BCJ_ARM:
|
---|
| 540 | #endif
|
---|
| 541 | #ifdef XZ_DEC_ARMTHUMB
|
---|
| 542 | case BCJ_ARMTHUMB:
|
---|
| 543 | #endif
|
---|
| 544 | #ifdef XZ_DEC_SPARC
|
---|
| 545 | case BCJ_SPARC:
|
---|
| 546 | #endif
|
---|
| 547 | break;
|
---|
| 548 |
|
---|
| 549 | default:
|
---|
| 550 | /* Unsupported Filter ID */
|
---|
| 551 | return XZ_OPTIONS_ERROR;
|
---|
| 552 | }
|
---|
| 553 |
|
---|
| 554 | s->type = id;
|
---|
| 555 | s->ret = XZ_OK;
|
---|
| 556 | s->pos = 0;
|
---|
| 557 | s->x86_prev_mask = 0;
|
---|
| 558 | s->temp.filtered = 0;
|
---|
| 559 | s->temp.size = 0;
|
---|
| 560 |
|
---|
| 561 | return XZ_OK;
|
---|
| 562 | }
|
---|
| 563 |
|
---|
| 564 | #endif
|
---|