ia64.c revision 292588 
1///////////////////////////////////////////////////////////////////////////////
2//
3/// \file       ia64.c
4/// \brief      Filter for IA64 (Itanium) binaries
5///
6//  Authors:    Igor Pavlov
7//              Lasse Collin
8//
9//  This file has been put into the public domain.
10//  You can do whatever you want with this file.
11//
12///////////////////////////////////////////////////////////////////////////////
13
14#include "simple_private.h"
15
16
17static size_t
18ia64_code(lzma_simple *simple lzma_attribute((__unused__)),
19		uint32_t now_pos, bool is_encoder,
20		uint8_t *buffer, size_t size)
21{
22	static const uint32_t BRANCH_TABLE[32] = {
23		0, 0, 0, 0, 0, 0, 0, 0,
24		0, 0, 0, 0, 0, 0, 0, 0,
25		4, 4, 6, 6, 0, 0, 7, 7,
26		4, 4, 0, 0, 4, 4, 0, 0
27	};
28
29	size_t i;
30	for (i = 0; i + 16 <= size; i += 16) {
31		const uint32_t instr_template = buffer[i] & 0x1F;
32		const uint32_t mask = BRANCH_TABLE[instr_template];
33		uint32_t bit_pos = 5;
34
35		for (size_t slot = 0; slot < 3; ++slot, bit_pos += 41) {
36			if (((mask >> slot) & 1) == 0)
37				continue;
38
39			const size_t byte_pos = (bit_pos >> 3);
40			const uint32_t bit_res = bit_pos & 0x7;
41			uint64_t instruction = 0;
42
43			for (size_t j = 0; j < 6; ++j)
44				instruction += (uint64_t)(
45						buffer[i + j + byte_pos])
46						<< (8 * j);
47
48			uint64_t inst_norm = instruction >> bit_res;
49
50			if (((inst_norm >> 37) & 0xF) == 0x5
51					&& ((inst_norm >> 9) & 0x7) == 0
52					/* &&  (inst_norm & 0x3F)== 0 */
53					) {
54				uint32_t src = (uint32_t)(
55						(inst_norm >> 13) & 0xFFFFF);
56				src |= ((inst_norm >> 36) & 1) << 20;
57
58				src <<= 4;
59
60				uint32_t dest;
61				if (is_encoder)
62					dest = now_pos + (uint32_t)(i) + src;
63				else
64					dest = src - (now_pos + (uint32_t)(i));
65
66				dest >>= 4;
67
68				inst_norm &= ~((uint64_t)(0x8FFFFF) << 13);
69				inst_norm |= (uint64_t)(dest & 0xFFFFF) << 13;
70				inst_norm |= (uint64_t)(dest & 0x100000)
71						<< (36 - 20);
72
73				instruction &= (1 << bit_res) - 1;
74				instruction |= (inst_norm << bit_res);
75
76				for (size_t j = 0; j < 6; j++)
77					buffer[i + j + byte_pos] = (uint8_t)(
78							instruction
79							>> (8 * j));
80			}
81		}
82	}
83
84	return i;
85}
86
87
88static lzma_ret
89ia64_coder_init(lzma_next_coder *next, const lzma_allocator *allocator,
90		const lzma_filter_info *filters, bool is_encoder)
91{
92	return lzma_simple_coder_init(next, allocator, filters,
93			&ia64_code, 0, 16, 16, is_encoder);
94}
95
96
97extern lzma_ret
98lzma_simple_ia64_encoder_init(lzma_next_coder *next,
99		const lzma_allocator *allocator,
100		const lzma_filter_info *filters)
101{
102	return ia64_coder_init(next, allocator, filters, true);
103}
104
105
106extern lzma_ret
107lzma_simple_ia64_decoder_init(lzma_next_coder *next,
108		const lzma_allocator *allocator,
109		const lzma_filter_info *filters)
110{
111	return ia64_coder_init(next, allocator, filters, false);
112}
113