diff options
Diffstat (limited to 'grub-core/boot/i386/pc/lzma_decode.S')
| -rw-r--r-- | grub-core/boot/i386/pc/lzma_decode.S | 614 |
1 files changed, 614 insertions, 0 deletions
diff --git a/grub-core/boot/i386/pc/lzma_decode.S b/grub-core/boot/i386/pc/lzma_decode.S new file mode 100644 index 0000000..88c668d --- /dev/null +++ b/grub-core/boot/i386/pc/lzma_decode.S @@ -0,0 +1,614 @@ +/* + * GRUB -- GRand Unified Bootloader + * Copyright (C) 2008 Free Software Foundation, Inc. + * + * GRUB is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * GRUB is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with GRUB. If not, see <http://www.gnu.org/licenses/>. + */ + +#define FIXED_PROPS + +#define LZMA_BASE_SIZE 1846 +#define LZMA_LIT_SIZE 768 + +#define LZMA_PROPERTIES_SIZE 5 + +#define kNumTopBits 24 +#define kTopValue (1 << kNumTopBits) + +#define kNumBitModelTotalBits 11 +#define kBitModelTotal (1 << kNumBitModelTotalBits) +#define kNumMoveBits 5 + + +#define kNumPosBitsMax 4 +#define kNumPosStatesMax (1 << kNumPosBitsMax) + +#define kLenNumLowBits 3 +#define kLenNumLowSymbols (1 << kLenNumLowBits) +#define kLenNumMidBits 3 +#define kLenNumMidSymbols (1 << kLenNumMidBits) +#define kLenNumHighBits 8 +#define kLenNumHighSymbols (1 << kLenNumHighBits) + +#define LenChoice 0 +#define LenChoice2 (LenChoice + 1) +#define LenLow (LenChoice2 + 1) +#define LenMid (LenLow + (kNumPosStatesMax << kLenNumLowBits)) +#define LenHigh (LenMid + (kNumPosStatesMax << kLenNumMidBits)) +#define kNumLenProbs (LenHigh + kLenNumHighSymbols) + + +#define kNumStates 12 +#define kNumLitStates 7 + +#define kStartPosModelIndex 4 +#define kEndPosModelIndex 14 +#define kNumFullDistances (1 << (kEndPosModelIndex >> 1)) + +#define kNumPosSlotBits 6 +#define kNumLenToPosStates 4 + +#define kNumAlignBits 4 +#define kAlignTableSize (1 << kNumAlignBits) + +#define kMatchMinLen 2 + +#define IsMatch 0 +#define IsRep (IsMatch + (kNumStates << kNumPosBitsMax)) +#define IsRepG0 (IsRep + kNumStates) +#define IsRepG1 (IsRepG0 + kNumStates) +#define IsRepG2 (IsRepG1 + kNumStates) +#define IsRep0Long (IsRepG2 + kNumStates) +#define PosSlot (IsRep0Long + (kNumStates << kNumPosBitsMax)) +#define SpecPos (PosSlot + (kNumLenToPosStates << kNumPosSlotBits)) +#define Align (SpecPos + kNumFullDistances - kEndPosModelIndex) +#define LenCoder (Align + kAlignTableSize) +#define RepLenCoder (LenCoder + kNumLenProbs) +#define Literal (RepLenCoder + kNumLenProbs) + +#define out_size 8(%ebp) + +#define now_pos -4(%ebp) +#define prev_byte -8(%ebp) +#define range -12(%ebp) +#define code -16(%ebp) +#define state -20(%ebp) +#define rep0 -24(%ebp) +#define rep1 -28(%ebp) +#define rep2 -32(%ebp) +#define rep3 -36(%ebp) + +#ifdef FIXED_PROPS + +#define FIXED_LC 3 +#define FIXED_LP 0 +#define FIXED_PB 2 + +#define POS_STATE_MASK ((1 << (FIXED_PB)) - 1) +#define LIT_POS_MASK ((1 << (FIXED_LP)) - 1) + +#define LOCAL_SIZE 36 + +#else + +#define lc (%ebx) +#define lp 4(%ebx) +#define pb 8(%ebx) +#define probs 12(%ebx) + +#define pos_state_mask -40(%ebp) +#define lit_pos_mask -44(%ebp) + +#define LOCAL_SIZE 44 + +#endif + +RangeDecoderBitDecode: +#ifdef FIXED_PROPS + leal (%ebx, %eax, 4), %eax +#else + shll $2, %eax + addl probs, %eax +#endif + + movl %eax, %ecx + movl (%ecx), %eax + + movl range, %edx + shrl $kNumBitModelTotalBits, %edx + mull %edx + + cmpl code, %eax + jbe 1f + + movl %eax, range + movl $kBitModelTotal, %edx + subl (%ecx), %edx + shrl $kNumMoveBits, %edx + addl %edx, (%ecx) + clc +3: + pushf + cmpl $kTopValue, range + jnc 2f + shll $8, code + lodsb + movb %al, code + shll $8, range +2: + popf + ret +1: + subl %eax, range + subl %eax, code + movl (%ecx), %edx + shrl $kNumMoveBits, %edx + subl %edx, (%ecx) + stc + jmp 3b + +RangeDecoderBitTreeDecode: +RangeDecoderReverseBitTreeDecode: + movzbl %cl, %ecx + xorl %edx, %edx + pushl %edx + incl %edx + pushl %edx + +1: + pushl %eax + pushl %ecx + pushl %edx + + addl %edx, %eax + call RangeDecoderBitDecode + + popl %edx + popl %ecx + + jnc 2f + movl 4(%esp), %eax + orl %eax, 8(%esp) + stc + +2: + adcl %edx, %edx + popl %eax + + shll $1, (%esp) + loop 1b + + popl %ecx + subl %ecx, %edx /* RangeDecoderBitTreeDecode */ + popl %ecx /* RangeDecoderReverseBitTreeDecode */ + ret + +LzmaLenDecode: + pushl %eax + addl $LenChoice, %eax + call RangeDecoderBitDecode + popl %eax + jc 1f + pushl $0 + movb $kLenNumLowBits, %cl + addl $LenLow, %eax +2: + movl 12(%esp), %edx + shll %cl, %edx + addl %edx, %eax +3: + + call RangeDecoderBitTreeDecode + popl %eax + addl %eax, %edx + ret + +1: + pushl %eax + addl $LenChoice2, %eax + call RangeDecoderBitDecode + popl %eax + jc 1f + pushl $kLenNumLowSymbols + movb $kLenNumMidBits, %cl + addl $LenMid, %eax + jmp 2b + +1: + pushl $(kLenNumLowSymbols + kLenNumMidSymbols) + addl $LenHigh, %eax + movb $kLenNumHighBits, %cl + jmp 3b + +WriteByte: + movb %al, prev_byte + stosb + incl now_pos + ret + +/* + * int LzmaDecode(CLzmaDecoderState *vs, + * const unsigned char *inStream, + * unsigned char *outStream, + * SizeT outSize); + */ + +_LzmaDecodeA: + + pushl %ebp + movl %esp, %ebp + subl $LOCAL_SIZE, %esp + +#ifndef ASM_FILE + pushl %esi + pushl %edi + pushl %ebx + + movl %eax, %ebx + movl %edx, %esi + pushl %ecx +#else + pushl %edi +#endif + + cld + +#ifdef FIXED_PROPS + movl %ebx, %edi + movl $(Literal + (LZMA_LIT_SIZE << (FIXED_LC + FIXED_LP))), %ecx +#else + movl $LZMA_LIT_SIZE, %eax + movb lc, %cl + addb lp, %cl + shll %cl, %eax + addl $Literal, %eax + movl %eax, %ecx + movl probs, %edi +#endif + + movl $(kBitModelTotal >> 1), %eax + + rep + stosl + + popl %edi + + xorl %eax, %eax + movl %eax, now_pos + movl %eax, prev_byte + movl %eax, state + + incl %eax + movl %eax, rep0 + movl %eax, rep1 + movl %eax, rep2 + movl %eax, rep3 + +#ifndef FIXED_PROPS + movl %eax, %edx + movb pb, %cl + shll %cl, %edx + decl %edx + movl %edx, pos_state_mask + + movl %eax, %edx + movb lp, %cl + shll %cl, %edx + decl %edx + movl %edx, lit_pos_mask; +#endif + + /* RangeDecoderInit */ + negl %eax + movl %eax, range + + incl %eax + movb $5, %cl + +1: + shll $8, %eax + lodsb + loop 1b + + movl %eax, code + +lzma_decode_loop: + movl now_pos, %eax + cmpl out_size, %eax + + jb 1f + +#ifndef ASM_FILE + xorl %eax, %eax + + popl %ebx + popl %edi + popl %esi +#endif + + movl %ebp, %esp + popl %ebp + ret + +1: +#ifdef FIXED_PROPS + andl $POS_STATE_MASK, %eax +#else + andl pos_state_mask, %eax +#endif + pushl %eax /* posState */ + movl state, %edx + shll $kNumPosBitsMax, %edx + addl %edx, %eax + pushl %eax /* (state << kNumPosBitsMax) + posState */ + + call RangeDecoderBitDecode + jc 1f + + movl now_pos, %eax + +#ifdef FIXED_PROPS + andl $LIT_POS_MASK, %eax + shll $FIXED_LC, %eax + movl prev_byte, %edx + shrl $(8 - FIXED_LC), %edx +#else + andl lit_pos_mask, %eax + movb lc, %cl + shll %cl, %eax + negb %cl + addb $8, %cl + movl prev_byte, %edx + shrl %cl, %edx +#endif + + addl %edx, %eax + movl $LZMA_LIT_SIZE, %edx + mull %edx + addl $Literal, %eax + pushl %eax + + incl %edx /* edx = 1 */ + + movl rep0, %eax + negl %eax + pushl (%edi, %eax) /* matchByte */ + + cmpb $kNumLitStates, state + jb 5f + + /* LzmaLiteralDecodeMatch */ + +3: + cmpl $0x100, %edx + jae 4f + + xorl %eax, %eax + shlb $1, (%esp) + adcl %eax, %eax + + pushl %eax + pushl %edx + + shll $8, %eax + leal 0x100(%edx, %eax), %eax + addl 12(%esp), %eax + call RangeDecoderBitDecode + + setc %al + popl %edx + adcl %edx, %edx + + popl %ecx + cmpb %cl, %al + jz 3b + +5: + + /* LzmaLiteralDecode */ + + cmpl $0x100, %edx + jae 4f + + pushl %edx + movl %edx, %eax + addl 8(%esp), %eax + call RangeDecoderBitDecode + popl %edx + adcl %edx, %edx + jmp 5b + +4: + addl $16, %esp + + movb %dl, %al + call WriteByte + + movb state, %al + cmpb $4, %al + jae 2f + xorb %al, %al + jmp 3f +2: + subb $3, %al + cmpb $7, %al + jb 3f + subb $3, %al +3: + movb %al, state + jmp lzma_decode_loop + +1: + movl state, %eax + addl $IsRep, %eax + call RangeDecoderBitDecode + jnc 1f + + movl state, %eax + addl $IsRepG0, %eax + call RangeDecoderBitDecode + jc 10f + + movl (%esp), %eax + addl $IsRep0Long, %eax + call RangeDecoderBitDecode + jc 20f + + cmpb $7, state + movb $9, state + jb 100f + addb $2, state +100: + + movl $1, %ecx + +3: + movl rep0, %edx + negl %edx + +4: + movb (%edi, %edx), %al + call WriteByte + loop 4b + + popl %eax + popl %eax + jmp lzma_decode_loop + +10: + movl state, %eax + addl $IsRepG1, %eax + call RangeDecoderBitDecode + movl rep1, %edx + jnc 100f + + movl state, %eax + addl $IsRepG2, %eax + call RangeDecoderBitDecode + movl rep2, %edx + jnc 1000f + movl rep2, %edx + xchgl rep3, %edx +1000: + pushl rep1 + popl rep2 +100: + xchg rep0, %edx + movl %edx, rep1 +20: + + movl $RepLenCoder, %eax + call LzmaLenDecode + + cmpb $7, state + movb $8, state + jb 100f + addb $3, state +100: + jmp 2f + +1: + movl rep0, %eax + xchgl rep1, %eax + xchgl rep2, %eax + movl %eax, rep3 + + cmpb $7, state + movb $7, state + jb 10f + addb $3, state +10: + + movl $LenCoder, %eax + call LzmaLenDecode + pushl %edx + + movl $(kNumLenToPosStates - 1), %eax + cmpl %eax, %edx + jbe 100f + movl %eax, %edx +100: + movb $kNumPosSlotBits, %cl + shll %cl, %edx + leal PosSlot(%edx), %eax + call RangeDecoderBitTreeDecode + + movl %edx, rep0 + cmpl $kStartPosModelIndex, %edx + jb 100f + + movl %edx, %ecx + shrl $1, %ecx + decl %ecx + + movzbl %dl, %eax + andb $1, %al + orb $2, %al + shll %cl, %eax + movl %eax, rep0 + + cmpl $kEndPosModelIndex, %edx + jae 200f + movl rep0, %eax + addl $(SpecPos - 1), %eax + subl %edx, %eax + jmp 300f +200: + + subb $kNumAlignBits, %cl + + /* RangeDecoderDecodeDirectBits */ + xorl %edx, %edx + +1000: + shrl $1, range + shll $1, %edx + + movl range, %eax + cmpl %eax, code + jb 2000f + subl %eax, code + orb $1, %dl +2000: + + cmpl $kTopValue, %eax + jae 3000f + shll $8, range + shll $8, code + lodsb + movb %al, code + +3000: + loop 1000b + + movb $kNumAlignBits, %cl + shll %cl, %edx + addl %edx, rep0 + + movl $Align, %eax + +300: + call RangeDecoderReverseBitTreeDecode + addl %ecx, rep0 + +100: + incl rep0 + popl %edx + +2: + + addl $kMatchMinLen, %edx + movl %edx, %ecx + + jmp 3b |