1 Commits
v0.2.0 ... z80

Author SHA1 Message Date
48727040b3 Merge pull request #5 from ped7g/z80_ped7g
Z80 ped7g - further optimisations
2022-09-27 22:35:44 +02:00
28 changed files with 253 additions and 1616 deletions

66
Cargo.lock generated
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@@ -62,12 +62,6 @@ version = "1.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index" source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646" checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
[[package]]
name = "lexopt"
version = "0.2.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "478ee9e62aaeaf5b140bd4138753d1f109765488581444218d3ddda43234f3e8"
[[package]] [[package]]
name = "libc" name = "libc"
version = "0.2.108" version = "0.2.108"
@@ -96,22 +90,10 @@ dependencies = [
] ]
[[package]] [[package]]
name = "proc-macro2" name = "pico-args"
version = "1.0.44" version = "0.4.2"
source = "registry+https://github.com/rust-lang/crates.io-index" source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "7bd7356a8122b6c4a24a82b278680c73357984ca2fc79a0f9fa6dea7dced7c58" checksum = "db8bcd96cb740d03149cbad5518db9fd87126a10ab519c011893b1754134c468"
dependencies = [
"unicode-ident",
]
[[package]]
name = "quote"
version = "1.0.21"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "bbe448f377a7d6961e30f5955f9b8d106c3f5e449d493ee1b125c1d43c2b5179"
dependencies = [
"proc-macro2",
]
[[package]] [[package]]
name = "sacabase" name = "sacabase"
@@ -122,37 +104,6 @@ dependencies = [
"num-traits", "num-traits",
] ]
[[package]]
name = "syn"
version = "1.0.101"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "e90cde112c4b9690b8cbe810cba9ddd8bc1d7472e2cae317b69e9438c1cba7d2"
dependencies = [
"proc-macro2",
"quote",
"unicode-ident",
]
[[package]]
name = "thiserror"
version = "1.0.36"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "0a99cb8c4b9a8ef0e7907cd3b617cc8dc04d571c4e73c8ae403d80ac160bb122"
dependencies = [
"thiserror-impl",
]
[[package]]
name = "thiserror-impl"
version = "1.0.36"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "3a891860d3c8d66fec8e73ddb3765f90082374dbaaa833407b904a94f1a7eb43"
dependencies = [
"proc-macro2",
"quote",
"syn",
]
[[package]] [[package]]
name = "time" name = "time"
version = "0.1.44" version = "0.1.44"
@@ -164,21 +115,14 @@ dependencies = [
"winapi", "winapi",
] ]
[[package]]
name = "unicode-ident"
version = "1.0.4"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "dcc811dc4066ac62f84f11307873c4850cb653bfa9b1719cee2bd2204a4bc5dd"
[[package]] [[package]]
name = "upkr" name = "upkr"
version = "0.2.0" version = "0.1.0"
dependencies = [ dependencies = [
"anyhow", "anyhow",
"cdivsufsort", "cdivsufsort",
"lexopt",
"pbr", "pbr",
"thiserror", "pico-args",
] ]
[[package]] [[package]]

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@@ -1,14 +1,12 @@
[package] [package]
name = "upkr" name = "upkr"
version = "0.2.0" version = "0.1.0"
edition = "2021" edition = "2021"
[profile.release] # See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
strip = "debuginfo"
[dependencies] [dependencies]
cdivsufsort = "2" cdivsufsort = "2"
lexopt = "0.2.1" pico-args = "0.4"
anyhow = "1" anyhow = "1"
thiserror = "1.0.36"
pbr = "1" pbr = "1"

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@@ -2,57 +2,13 @@
Upkr is a simple general purpose lz packer designed to be used in the [MicroW8](https://github.com/exoticorn/microw8) platform. Upkr is a simple general purpose lz packer designed to be used in the [MicroW8](https://github.com/exoticorn/microw8) platform.
The compressed format is losely based on [Shrinkler](https://github.com/askeksa/Shrinkler) with the main difference being that The compressed format is losely based on [Shrinkler](https://github.com/askeksa/Shrinkler) with the main difference being that
Upkr doesn't differentiate between literals at odd or even addresses (by default) and that I went with rANS/rABS instead of a range coder. Upkr doesn't differnetiate between literals at odd or even addresses and that I went with rANS/rABS instead of a range coder.
Compression rate is on par with Shrinkler. At this point, Upkr should still be considered unstable - the compressed format is not very likely to change but I still want
to keep that option open a little longer.
The differences compare to Shrinkler also makes it interesting on 8bit platforms. The z80 unpacker included in the release
is both about twice as fast and smaller than the Shrinkler unpacker.
## Inspirations: ## Inspirations:
* Ferris' blog about his [C64 intro packer](https://yupferris.github.io/blog/2020/08/31/c64-4k-intro-packer-deep-dive.html) * Ferris' blog about his [C64 intro packer](https://yupferris.github.io/blog/2020/08/31/c64-4k-intro-packer-deep-dive.html)
* [Shrinkler](https://github.com/askeksa/Shrinkler) * [Shrinkler](https://github.com/askeksa/Shrinkler)
* Ryg's [sample rANS implementation](https://github.com/rygorous/ryg_rans) * Ryg's [sample rANS implementation](https://github.com/rygorous/ryg_rans)
## Unpackers
The release includes a reference c unpacker, as well as some optimized asm unpackers (arm and riscv). The unpckers in
c_unpacker and asm_unpackers unpack the default upkr compressed format. The z80_unpacker
is based on some variations to the compressed format. (Use `upkr --z80` to select those variations.)
An optimized x86 (DOS) unpacker is currently being worked on out of tree.
## Usage
```
upkr [-l level(0-9)] [config options] <infile> [<outfile>]
upkr -u [config options] <infile> [<outfile>]
upkr --margin [config options] <infile>
-l, --level N compression level 0-9
-0, ..., -9 short form for setting compression level
-u, --unpack unpack infile
--margin calculate margin for overlapped unpacking of a packed file
Config presets for specific unpackers:
--z80 --big-endian-bitstream --invert-bit-encoding --simplified-prob-update -9
--x86 --bitstream --invert-is-match-bit --invert-continue-value-bit --invert-new-offset-bit
--x86b --bitstream --invert-continue-value-bit --no-repeated-offsets -9
Config options (need to match when packing/unpacking):
-b, --bitstream bitstream mode
-p, --parity N use N (2/4) parity contexts
-r, --reverse reverse input & output
Config options to tailor output to specific optimized unpackers:
--invert-is-match-bit
--invert-new-offset-bit
--invert-continue-value-bit
--invert-bit-encoding
--simplified-prob-update
--big-endian-bitstream (implies --bitstream)
--no-repeated-offsets
--eof-in-length
--max-offset N
--max-length N
```

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@@ -1 +0,0 @@
/build/

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@@ -1,64 +0,0 @@
build/unpack_riscv64: ../c_unpacker/main.c unpack_riscv.S
mkdir -p build
riscv64-linux-gnu-gcc -g -static -o $@ $^
test_riscv64: build/unpack_riscv64
qemu-riscv64 $< test_data.upk /tmp/out.bin
cmp test_data.bin /tmp/out.bin
build/unpack_riscv64.o: unpack_riscv.S
mkdir -p build
riscv64-linux-gnu-gcc -c -o $@ $?
build/unpack_riscv64.bin: build/unpack_riscv64.o
riscv64-linux-gnu-objcopy -O binary --only-section=.text $? $@
disas-riscv64: build/unpack_riscv64.o
riscv64-linux-gnu-objdump -d $?
build/unpack_riscv32.o: unpack_riscv.S
mkdir -p build
riscv64-linux-gnu-gcc -march=rv32imc -mabi=ilp32 -c -o $@ $?
build/unpack_riscv32.bin: build/unpack_riscv32.o
riscv64-linux-gnu-objcopy -O binary --only-section=.text $? $@
disas-riscv32: build/unpack_riscv32.o
riscv64-linux-gnu-objdump -d $?
build/unpack_armv6m: ../c_unpacker/main.c unpack_armv6m.S
mkdir -p build
arm-linux-gnueabihf-gcc -g -static -o $@ $^
test_armv6m: build/unpack_armv6m
qemu-arm $< test_data.upk /tmp/out.bin
cmp test_data.bin /tmp/out.bin
build/unpack_armv6m.bin: unpack_armv6m.S
mkdir -p build
arm-none-eabi-gcc -march=armv6-m -c -o build/unpack_armv6m.o $?
arm-none-eabi-objcopy -O binary --only-section=.text build/unpack_armv6m.o $@
build/unpack_arm32: ../c_unpacker/main.c unpack_arm32.S
mkdir -p build
arm-linux-gnueabihf-gcc -g -static -o $@ $^
test_arm32: build/unpack_arm32
qemu-arm $< test_data.upk /tmp/out.bin
cmp test_data.bin /tmp/out.bin
build/unpack_arm32.bin: unpack_arm32.S
mkdir -p build
arm-none-eabi-gcc -c -o build/unpack_arm32.o $?
arm-none-eabi-objcopy -O binary --only-section=.text build/unpack_arm32.o $@
build/unpack_c: ../c_unpacker/main.c ../c_unpacker/unpack.c
mkdir -p build
gcc -g -o $@ $^
test_c: build/unpack_c
$< test_data.upk /tmp/out.bin
cmp test_data.bin /tmp/out.bin
sizes: build/unpack_armv6m.bin build/unpack_riscv64.bin build/unpack_riscv32.bin build/unpack_arm32.bin
ls -l build/*.bin

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@@ -1,99 +0,0 @@
typedef unsigned char u8;
typedef unsigned short u16;
typedef unsigned long u32;
u8* upkr_data_ptr;
u8 upkr_probs[1 + 255 + 1 + 2*32 + 2*32];
#ifdef UPKR_BITSTREAM
u16 upkr_state;
u8 upkr_current_byte;
int upkr_bits_left;
#else
u32 upkr_state;
#endif
int upkr_decode_bit(int context_index) {
#ifdef UPKR_BITSTREAM
while(upkr_state < 32768) {
if(upkr_bits_left == 0) {
upkr_current_byte = *upkr_data_ptr++;
upkr_bits_left = 8;
}
upkr_state = (upkr_state << 1) + (upkr_current_byte & 1);
upkr_current_byte >>= 1;
--upkr_bits_left;
}
#else
while(upkr_state < 4096) {
upkr_state = (upkr_state << 8) | *upkr_data_ptr++;
}
#endif
int prob = upkr_probs[context_index];
int bit = (upkr_state & 255) < prob ? 1 : 0;
int tmp = prob;
if(!bit) {
tmp = 256 - tmp;
}
upkr_state = tmp * (upkr_state >> 8) + (upkr_state & 255);
tmp += (256 - tmp + 8) >> 4;
if(!bit) {
upkr_state -= prob;
tmp = 256 - tmp;
}
upkr_probs[context_index] = tmp;
return bit;
}
int upkr_decode_length(int context_index) {
int length = 0;
int bit_pos = 0;
while(upkr_decode_bit(context_index)) {
length |= upkr_decode_bit(context_index + 1) << bit_pos++;
context_index += 2;
}
return length | (1 << bit_pos);
}
void* upkr_unpack(void* destination, void* compressed_data) {
upkr_data_ptr = (u8*)compressed_data;
upkr_state = 0;
#ifdef UPKR_BITSTREAM
upkr_bits_left = 0;
#endif
for(int i = 0; i < sizeof(upkr_probs); ++i)
upkr_probs[i] = 128;
u8* write_ptr = (u8*)destination;
int prev_was_match = 0;
int offset = 0;
for(;;) {
if(upkr_decode_bit(0)) {
if(prev_was_match || upkr_decode_bit(256)) {
offset = upkr_decode_length(257) - 1;
if(offset == 0) {
break;
}
}
int length = upkr_decode_length(257 + 64);
while(length--) {
*write_ptr = write_ptr[-offset];
++write_ptr;
}
prev_was_match = 1;
} else {
int byte = 1;
while(byte < 256) {
int bit = upkr_decode_bit(byte);
byte = (byte << 1) + bit;
}
*write_ptr++ = byte;
prev_was_match = 0;
}
}
return write_ptr;
}

Binary file not shown.

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@@ -1,100 +0,0 @@
.arm
.section .text
.global upkr_unpack
.type upkr_unpack, %function
// r0 .. out_ptr (returned)
// r1 .. in_ptr (returned)
// r2 .. state
// r3 .. offset
// r4 .. prev_was_literal / decode_length ret
// r5 .. context index
// r6 .. decode_length temp
// r7 .. probs ptr
// r8-r11 .. decode_bit temp
// r12 .. decode_length return address
upkr_unpack:
push { r3-r11, lr }
mov r2, #384
mov r3, #128
.Lclear:
subs r2, r2, #1
strb r3, [sp, -r2]
bne .Lclear
.Lloop:
mov r5, #0
bl upkr_decode_bit
bcc .Ldata
.Lmatch:
mov r5, #256
rsbs r6, r4, #0
blcc upkr_decode_bit
bcc .Lskip_offset
bl upkr_decode_length
adds r3, r4, #1
popeq { r3-r11, pc }
.Lskip_offset:
mov r5, #256+64
bl upkr_decode_length
.Lcopy_loop:
ldrb r5, [r0, r3]
.Lstore:
strb r5, [r0], #1
adds r4, r4, #1
blt .Lcopy_loop
b .Lloop
.Ldata:
mov r5, #1
.Ldata_loop:
bl upkr_decode_bit
adc r5, r5, r5
movs r4, r5, lsr #8
beq .Ldata_loop
b .Lstore
.type upkr_decode_length, %function
upkr_decode_length:
mov r12, lr
mov r4, #0
mvn r6, #0
.Lbit_loop:
bl upkr_decode_bit_inc
addcc r4, r4, r6
movcc pc, r12
bl upkr_decode_bit_inc
addcs r4, r4, r6
mov r6, r6, lsl #1
b .Lbit_loop
.type upkr_decode_bit, %function
upkr_decode_bit_inc:
add r5, r5, #1
upkr_decode_bit:
cmp r2, #4096
ldrltb r8, [r1], #1
orrlt r2, r8, r2, lsl#8
blt upkr_decode_bit
ldrb r8, [sp, -r5]
and r9, r2, #255
add r9, r9, #1
cmp r8, r9
rsbcs r8, r8, #256
mvn r9, r2, lsr#8
addcs r9, r9, #1
mla r2, r8, r9, r2
add r9, r8, #8
sub r8, r8, r9, lsr#4
rsbcs r8, r8, #256
strb r8, [sp, -r5]
mov pc, r14

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@@ -1,162 +0,0 @@
// armv6-m upkr unpacker by yrlf
// some optimizations by exoticorn
.syntax unified
.thumb
.section .text
#define ALIGNUP(n, align) (((n) + (align) - 1) & ~((align) - 1))
#define PROB_LEN (1 + 255 + 1 + 2*32 + 2*32)
#define FRAME_SIZE ALIGNUP(PROB_LEN, 4)
// auto upkr_unpack(uint8_t * out, uint8_t * in) -> tuple<uint8_t *, uint8_t *>
.global upkr_unpack
.type upkr_unpack, %function
// r0 .. out_ptr (returned)
// r1 .. in_ptr (returned)
// r2 .. state
// r3 .. offset
// r4 .. prev_was_literal / decode_length ret
// r5 .. subroutine arg (preserved)
// r6 .. decode_bit ret
// r7 .. probs ptr
upkr_unpack:
push { r4, r5, r6, r7, lr }
sub sp, sp, #FRAME_SIZE
mov r7, sp
movs r2, #255
adds r2, r2, #(PROB_LEN - 255)
movs r3, #128
.Lclear:
subs r2, r2, #1
strb r3, [r7, r2]
bne .Lclear
.Lloop:
movs r5, #0
bl upkr_decode_bit
beq .Ldata
.Lmatch:
// r6 = 1
lsls r5, r6, #8
cmp r4, #0
beq 1f
bl upkr_decode_bit
beq 2f
1:
bl upkr_decode_length
adds r3, r4, #1
beq .Lend
2:
adds r5, r5, #64
bl upkr_decode_length
.Lcopy_loop:
ldrb r5, [r0, r3]
.Lstore:
strb r5, [r0]
adds r0, r0, #1
adds r4, r4, #1
blt .Lcopy_loop
b .Lloop
.Ldata:
movs r5, #1
.Ldata_loop:
bl upkr_decode_bit
adcs r5, r5, r5
lsrs r4, r5, #8
beq .Ldata_loop
b .Lstore
.Lend:
add sp, sp, #FRAME_SIZE
pop { r4, r5, r6, r7, pc }
.type upkr_decode_length, %function
// r0 .. -length tmp (saved)
// r1 ..
// r2 ..
// r3 ..
// r4 .. -length (returned)
// r5 .. context index (saved)
// r6 .. (saved)
// r7 ..
upkr_decode_length:
push { r0, r5, r6, lr }
movs r0, #0
subs r4, r0, #1
.Lbit_loop:
adds r5, r5, #1
bl upkr_decode_bit
beq 1f
adds r5, r5, #1
bl upkr_decode_bit
beq 2f
adds r0, r0, r4
2:
lsls r4, r4, #1
b .Lbit_loop
1:
adds r4, r4, r0
pop { r0, r5, r6, pc }
.type upkr_decode_bit, %function
// r0 .. tmp / prob (saved)
// r1 .. in_ptr (modified)
// r2 .. state (modified)
// r3 .. scratch (saved)
// r4 ..
// r5 .. context index (preserved)
// r6 .. bit (returned)
// r7 .. probs ptr (preserved)
upkr_fill_state:
lsls r2, r2, #8
ldrb r6, [r1]
adds r1, r1, #1
orrs r2, r2, r6
upkr_decode_bit:
lsrs r6, r2, #12
beq upkr_fill_state
push { r0, r1, r3, lr }
ldrb r0, [r7, r5]
lsrs r3, r2, #8
uxtb r1, r2
subs r6, r1, r0
blt 1f
subs r1, r2, r0
rsbs r0, r0, #0
1:
muls r3, r3, r0
adds r2, r1, r3
rsbs r3, r0, #0
uxtb r3, r3
lsrs r3, r3, #4
adcs r0, r0, r3
cmp r6, #0
blt 1f
rsbs r0, r0, #0
1:
strb r0, [r7, r5]
lsrs r6, r6, #31
pop { r0, r1, r3, pc }

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@@ -1,131 +0,0 @@
.section .text
// x9 prev was literal
// x10 out ptr
// x11 in ptr
// x12 offset
// x13 state
// x14 context index
.global upkr_unpack
.type upkr_unpack, %function
upkr_unpack:
mv t4, ra
mv x17, x8
mv t6, x9
li x9, 256 + 128
mv x13, x9
1:
sub x8, sp, x13
sb x9, 0(x8)
addi x13, x13, -1
bnez x13, 1b
.Lmainloop:
li x14, 0
jal upkr_decode_bit
beqz x15, .Lliteral
slli x14, x14, 8
beqz x9, .Lread_offset_inc_x14
jal upkr_decode_bit
bnez x15, .Lread_offset
.Lfinished_offset:
addi x14, x14, 64
jalr ra // jal upkr_decode_number
1:
add x14, x10, t0
lbu x14, (x14)
.Lstore_byte:
sb x14, (x10)
addi x10, x10, 1
addi x9, x9, 1
blt x9, x0, 1b
j .Lmainloop
.Lliteral:
jal upkr_decode_bit
addi x14, x14, -1
slli x14, x14, 1
add x14, x14, x15
srli x9, x14, 8
beqz x9, .Lliteral
j .Lstore_byte
.Lread_offset_inc_x14:
addi x14, x14, 1
.Lread_offset:
jalr ra // jal upkr_decode_number
addi t0, x9, 1
bnez t0, .Lfinished_offset
.Ldone:
mv x8, x17
mv x9, t6
jr t4
upkr_load_byte:
lbu x15, 0(x11)
addi x11, x11, 1
slli x13, x13, 8
add x13, x13, x15
// x8 prob array ptr
// x11 in ptr
// x13 state
// x14 context index
// return:
// x14 context index + 1
// x15 decoded bit
upkr_decode_bit:
srli x15, x13, 12
beqz x15, upkr_load_byte
addi x14, x14, 1
sub t2, sp, x14
lbu x12, (t2)
andi x8, x13, 255
sltu x15, x8, x12
beqz x15, 1f
xori x12, x12, 255
addi x12, x12, 1
1:
srli x8, x13, 8
addi x8, x8, 1
sub x8, x8, x15
mul x8, x8, x12
sub x13, x13, x8
addi x8, x12, 8
srli x8, x8, 4
sub x12, x12, x8
beqz x15, 1f
sub x12, x0, x12
1:
sb x12, (t2)
jalr ra
// x14 context index
// return: x9 negtive decoded number
upkr_decode_number:
mv t3, ra
mv t5, x14
li x9, 0
li t1, -1
1:
jal upkr_decode_bit
beqz x15, 1f
jal upkr_decode_bit
beqz x15, 2f
add x9, x9, t1
2:
add t1, t1, t1
j 1b
1:
add x9, x9, t1
mv x14, t5
jr t3

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@@ -1,33 +0,0 @@
int upkr_decode_bit(int context_index) {
#ifdef UPKR_BITSTREAM
while(upkr_state < 32768) {
if(upkr_bits_left == 0) {
upkr_current_byte = *upkr_data_ptr++;
upkr_bits_left = 8;
}
upkr_state = (upkr_state << 1) + (upkr_current_byte & 1);
upkr_current_byte >>= 1;
--upkr_bits_left;
}
#else
while(upkr_state < 4096) {
upkr_state = (upkr_state << 8) | *upkr_data_ptr++;
}
#endif
int prob = upkr_probs[context_index];
int bit = (upkr_state & 255) < prob ? 1 : 0;
if(bit) {
prob = 256 - prob;
}
upkr_state -= prob * ((upkr_state >> 8) + (bit ^ 1));
prob -= (prob + 8) >> 4;
if(bit) {
prob = -prob;
}
upkr_probs[context_index] = prob;
return bit;
}

View File

@@ -1,7 +1,7 @@
#include <stdio.h> #include <stdio.h>
#include <stdlib.h> #include <stdlib.h>
void* upkr_unpack(void* destination, void* compressed_data); int upkr_unpack(void* destination, void* compressed_data);
int main(int argn, char** argv) { int main(int argn, char** argv) {
void* input_buffer = malloc(1024*1024); void* input_buffer = malloc(1024*1024);
@@ -13,8 +13,7 @@ int main(int argn, char** argv) {
printf("Compressed size: %d\n", in_size); printf("Compressed size: %d\n", in_size);
void* end_ptr = upkr_unpack(output_buffer, input_buffer); int out_size = upkr_unpack(output_buffer, input_buffer);
int out_size = (char*)end_ptr - (char*)output_buffer;
printf("Uncompressed size: %d\n", out_size); printf("Uncompressed size: %d\n", out_size);

View File

@@ -19,8 +19,8 @@ int upkr_decode_bit(int context_index) {
upkr_current_byte = *upkr_data_ptr++; upkr_current_byte = *upkr_data_ptr++;
upkr_bits_left = 8; upkr_bits_left = 8;
} }
upkr_state = (upkr_state << 1) + (upkr_current_byte & 1); upkr_state = (upkr_state << 1) + (upkr_current_byte >> 7);
upkr_current_byte >>= 1; upkr_current_byte <<= 1;
--upkr_bits_left; --upkr_bits_left;
} }
#else #else
@@ -30,16 +30,18 @@ int upkr_decode_bit(int context_index) {
#endif #endif
int prob = upkr_probs[context_index]; int prob = upkr_probs[context_index];
int bit = (upkr_state & 255) < prob ? 1 : 0; int bit = (upkr_state & 255) >= prob ? 1 : 0;
int prob_offset = 16;
int state_offset = 0;
int state_scale = prob;
if(bit) { if(bit) {
upkr_state = prob * (upkr_state >> 8) + (upkr_state & 255); state_offset = -prob;
prob += (256 - prob + 8) >> 4; state_scale = 256 - prob;
} else { prob_offset = 0;
upkr_state = (256 - prob) * (upkr_state >> 8) + (upkr_state & 255) - prob;
prob -= (prob + 8) >> 4;
} }
upkr_probs[context_index] = prob; upkr_state = state_offset + state_scale * (upkr_state >> 8) + (upkr_state & 255);
upkr_probs[context_index] = prob_offset + prob - ((prob + 8) >> 4);
return bit; return bit;
} }
@@ -54,7 +56,7 @@ int upkr_decode_length(int context_index) {
return length | (1 << bit_pos); return length | (1 << bit_pos);
} }
void* upkr_unpack(void* destination, void* compressed_data) { int upkr_unpack(void* destination, void* compressed_data) {
upkr_data_ptr = (u8*)compressed_data; upkr_data_ptr = (u8*)compressed_data;
upkr_state = 0; upkr_state = 0;
#ifdef UPKR_BITSTREAM #ifdef UPKR_BITSTREAM
@@ -92,5 +94,5 @@ void* upkr_unpack(void* destination, void* compressed_data) {
} }
} }
return write_ptr; return write_ptr - (u8*)destination;
} }

50
compare-variants Executable file
View File

@@ -0,0 +1,50 @@
#!/bin/env ruby
configs = [
[:master, '-b'],
[:z80, '-b'],
[:z80, ['-b', '-r']],
['old-prob-update', '-b']
]
files = Dir[ARGV[0] + '/*'].select {|f| !(f =~ /\.txt$/) }
short_names = files.map {|f| File.basename(f)[..16] }
results = []
def print_results(configs, names, results)
configs.each_with_index do |config, i|
printf "%d: %s\n", i + 1, config
end
print ' '
configs.each_index do |i|
printf " %-4d", i + 1
end
puts
names.each_with_index do |name, i|
printf "%16s", name
for res in results
res = res[i]
printf " %-4s", res if res
end
puts
end
end
for config in configs
raise unless system('git', 'checkout', config[0].to_s)
config_results = []
results << config_results
for file in files
if system(*['cargo', 'run', '--release', 'pack', '-l', '9', config[1], file, '/tmp/out.upk'].flatten) &&
system(*['cargo', 'run', '--release', 'unpack', config[1], '/tmp/out.upk', '/tmp/out.bin'].flatten) &&
File.read(file) == File.read('/tmp/out.bin')
size = File.size('/tmp/out.upk')
config_results << size
else
config_results << 'ERR'
end
print_results(configs, short_names, results)
end
end

3
fuzz/.gitignore vendored
View File

@@ -1,3 +0,0 @@
target
corpus
artifacts

247
fuzz/Cargo.lock generated
View File

@@ -1,247 +0,0 @@
# This file is automatically @generated by Cargo.
# It is not intended for manual editing.
version = 3
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name = "anyhow"
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name = "upkr"
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"anyhow",
"cdivsufsort",
"lexopt",
"pbr",
"thiserror",
]
[[package]]
name = "upkr-fuzz"
version = "0.0.0"
dependencies = [
"libfuzzer-sys",
"upkr",
]
[[package]]
name = "wasi"
version = "0.10.0+wasi-snapshot-preview1"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "1a143597ca7c7793eff794def352d41792a93c481eb1042423ff7ff72ba2c31f"
[[package]]
name = "winapi"
version = "0.3.9"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "5c839a674fcd7a98952e593242ea400abe93992746761e38641405d28b00f419"
dependencies = [
"winapi-i686-pc-windows-gnu",
"winapi-x86_64-pc-windows-gnu",
]
[[package]]
name = "winapi-i686-pc-windows-gnu"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
[[package]]
name = "winapi-x86_64-pc-windows-gnu"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
checksum = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"

View File

@@ -1,31 +0,0 @@
[package]
name = "upkr-fuzz"
version = "0.0.0"
authors = ["Automatically generated"]
publish = false
edition = "2018"
[package.metadata]
cargo-fuzz = true
[dependencies]
libfuzzer-sys = "0.4"
[dependencies.upkr]
path = ".."
# Prevent this from interfering with workspaces
[workspace]
members = ["."]
[[bin]]
name = "all_configs"
path = "fuzz_targets/all_configs.rs"
test = false
doc = false
[[bin]]
name = "unpack"
path = "fuzz_targets/unpack.rs"
test = false
doc = false

View File

@@ -1,29 +0,0 @@
#![no_main]
use libfuzzer_sys::fuzz_target;
fuzz_target!(|data: &[u8]| {
let mut config = upkr::Config::default();
let mut level = 1;
let mut data = data;
if data.len() > 2 {
let flags1 = data[0];
let flags2 = data[1];
data = &data[2..];
config.use_bitstream = (flags1 & 1) != 0;
config.parity_contexts = if (flags1 & 2) == 0 { 1 } else { 2 };
config.invert_bit_encoding = (flags1 & 4) != 0;
config.is_match_bit = (flags1 & 8) != 0;
config.new_offset_bit = (flags1 & 16) != 0;
config.continue_value_bit = (flags1 & 32) != 0;
config.bitstream_is_big_endian = (flags1 & 64) != 0;
config.simplified_prob_update = (flags1 & 128) != 0;
config.no_repeated_offsets = (flags2 & 32) != 0;
config.eof_in_length = (flags2 & 1) != 0;
config.max_offset = if (flags2 & 2) == 0 { usize::MAX } else { 32 };
config.max_length = if (flags2 & 4) == 0 { usize::MAX } else { 5 };
level = (flags2 >> 3) & 3;
}
let packed = upkr::pack(data, level, &config, None);
let unpacked = upkr::unpack(&packed, &config, 1024 * 1024).unwrap();
assert!(unpacked == data);
});

View File

@@ -1,6 +0,0 @@
#![no_main]
use libfuzzer_sys::fuzz_target;
fuzz_target!(|data: &[u8]| {
let _ = upkr::unpack(data, &upkr::Config::default(), 64 * 1024);
});

4
release/.gitignore vendored
View File

@@ -1,4 +0,0 @@
*.zip
*.tgz
upkr-linux/
upkr-windows/

View File

@@ -1,35 +0,0 @@
VERSION := $(shell cargo run --release -- --version)
all: clean upkr-linux-$(VERSION).tgz upkr-windows-$(VERSION).zip
clean:
rm -rf upkr-linux
rm -f upkr-linux*.tgz
rm -rf upkr-windows
rm -f upkr-windows*.zip
upkr-linux-$(VERSION).tgz: upkr-linux/upkr PHONY
cp ../README.md upkr-linux
cd .. && git archive HEAD c_unpacker | tar -xC release/upkr-linux
cd .. && git archive HEAD z80_unpacker | tar -xC release/upkr-linux
cd .. && git archive HEAD asm_unpackers | tar -xC release/upkr-linux
tar czf $@ upkr-linux
upkr-windows-$(VERSION).zip: upkr-windows/upkr.exe PHONY
cp ../README.md upkr-windows/
cd .. && git archive HEAD c_unpacker | tar -xC release/upkr-windows
cd .. && git archive HEAD z80_unpacker | tar -xC release/upkr-windows
cd .. && git archive HEAD asm_unpackers | tar -xC release/upkr-windows
zip -r -9 $@ upkr-windows
upkr-linux/upkr:
cargo build --target x86_64-unknown-linux-musl --release
mkdir -p upkr-linux
cp ../target/x86_64-unknown-linux-musl/release/upkr upkr-linux/
upkr-windows/upkr.exe:
cargo build --target x86_64-pc-windows-gnu --release
mkdir -p upkr-windows
cp ../target/x86_64-pc-windows-gnu/release/upkr.exe upkr-windows/
PHONY:

View File

@@ -1,17 +1,12 @@
use crate::{ use crate::rans::{ONE_PROB, PROB_BITS};
rans::{ONE_PROB, PROB_BITS},
Config,
};
const INIT_PROB: u16 = 1 << (PROB_BITS - 1); const INIT_PROB: u16 = 1 << (PROB_BITS - 1);
const UPDATE_RATE: u32 = 4; const UPDATE_RATE: i32 = 4;
const UPDATE_ADD: u32 = 8; const UPDATE_ADD: i32 = 8;
#[derive(Clone)] #[derive(Clone)]
pub struct ContextState { pub struct ContextState {
contexts: Vec<u8>, contexts: Vec<u8>,
invert_bit_encoding: bool,
simplified_prob_update: bool,
} }
pub struct Context<'a> { pub struct Context<'a> {
@@ -20,11 +15,9 @@ pub struct Context<'a> {
} }
impl ContextState { impl ContextState {
pub fn new(size: usize, config: &Config) -> ContextState { pub fn new(size: usize) -> ContextState {
ContextState { ContextState {
contexts: vec![INIT_PROB as u8; size], contexts: vec![INIT_PROB as u8; size],
invert_bit_encoding: config.invert_bit_encoding,
simplified_prob_update: config.simplified_prob_update,
} }
} }
@@ -40,21 +33,13 @@ impl<'a> Context<'a> {
pub fn update(&mut self, bit: bool) { pub fn update(&mut self, bit: bool) {
let old = self.state.contexts[self.index]; let old = self.state.contexts[self.index];
let offset = if !bit {
self.state.contexts[self.index] = if self.state.simplified_prob_update {
let offset = if bit ^ self.state.invert_bit_encoding {
ONE_PROB as i32 >> UPDATE_RATE ONE_PROB as i32 >> UPDATE_RATE
} else { } else {
0 0
}; };
(offset + old as i32 - ((old as i32 + UPDATE_ADD as i32) >> UPDATE_RATE)) as u8 self.state.contexts[self.index] =
} else { (offset + old as i32 - ((old as i32 + UPDATE_ADD) >> UPDATE_RATE)) as u8;
if bit ^ self.state.invert_bit_encoding {
old + ((ONE_PROB - old as u32 + UPDATE_ADD) >> UPDATE_RATE) as u8
} else {
old - ((old as u32 + UPDATE_ADD) >> UPDATE_RATE) as u8
}
};
} }
} }

View File

@@ -1,16 +1,16 @@
use crate::lz;
use crate::match_finder::MatchFinder; use crate::match_finder::MatchFinder;
use crate::rans::RansCoder; use crate::rans::RansCoder;
use crate::ProgressCallback; use crate::ProgressCallback;
use crate::{lz, Config};
pub fn pack( pub fn pack(
data: &[u8], data: &[u8],
config: &Config, use_bitstream: bool,
mut progress_callback: Option<ProgressCallback>, mut progress_callback: Option<ProgressCallback>,
) -> Vec<u8> { ) -> Vec<u8> {
let mut match_finder = MatchFinder::new(data); let mut match_finder = MatchFinder::new(data);
let mut rans_coder = RansCoder::new(config); let mut rans_coder = RansCoder::new(use_bitstream);
let mut state = lz::CoderState::new(config); let mut state = lz::CoderState::new();
let mut pos = 0; let mut pos = 0;
while pos < data.len() { while pos < data.len() {
@@ -19,16 +19,15 @@ pub fn pack(
} }
let mut encoded_match = false; let mut encoded_match = false;
if let Some(m) = match_finder.matches(pos).next() { if let Some(m) = match_finder.matches(pos).next() {
let max_offset = config.max_offset.min(1 << (m.length * 3 - 1).min(31)); let max_offset = 1 << (m.length * 3 - 1).min(31);
let offset = pos - m.pos; let offset = pos - m.pos;
if offset < max_offset && m.length >= config.min_length() { if offset < max_offset {
let length = m.length.min(config.max_length);
lz::Op::Match { lz::Op::Match {
offset: offset as u32, offset: offset as u32,
len: length as u32, len: m.length as u32,
} }
.encode(&mut rans_coder, &mut state, config); .encode(&mut rans_coder, &mut state);
pos += length; pos += m.length;
encoded_match = true; encoded_match = true;
} }
} }
@@ -40,14 +39,13 @@ pub fn pack(
.iter() .iter()
.zip(data[(pos - offset)..].iter()) .zip(data[(pos - offset)..].iter())
.take_while(|(a, b)| a == b) .take_while(|(a, b)| a == b)
.count() .count();
.min(config.max_length); if length > 0 {
if length >= config.min_length() {
lz::Op::Match { lz::Op::Match {
offset: offset as u32, offset: offset as u32,
len: length as u32, len: length as u32,
} }
.encode(&mut rans_coder, &mut state, config); .encode(&mut rans_coder, &mut state);
pos += length; pos += length;
encoded_match = true; encoded_match = true;
} }
@@ -55,11 +53,11 @@ pub fn pack(
} }
if !encoded_match { if !encoded_match {
lz::Op::Literal(data[pos]).encode(&mut rans_coder, &mut state, config); lz::Op::Literal(data[pos]).encode(&mut rans_coder, &mut state);
pos += 1; pos += 1;
} }
} }
lz::encode_eof(&mut rans_coder, &mut state, config); lz::encode_eof(&mut rans_coder, &mut state);
rans_coder.finish() rans_coder.finish()
} }

View File

@@ -5,73 +5,20 @@ mod match_finder;
mod parsing_packer; mod parsing_packer;
mod rans; mod rans;
pub use lz::{calculate_margin, unpack, UnpackError}; pub use lz::unpack;
pub type ProgressCallback<'a> = &'a mut dyn FnMut(usize); pub type ProgressCallback<'a> = &'a mut dyn FnMut(usize);
#[derive(Debug)]
pub struct Config {
pub use_bitstream: bool,
pub parity_contexts: usize,
pub invert_bit_encoding: bool,
pub is_match_bit: bool,
pub new_offset_bit: bool,
pub continue_value_bit: bool,
pub bitstream_is_big_endian: bool,
pub simplified_prob_update: bool,
pub no_repeated_offsets: bool,
pub eof_in_length: bool,
pub max_offset: usize,
pub max_length: usize,
}
impl Default for Config {
fn default() -> Config {
Config {
use_bitstream: false,
parity_contexts: 1,
invert_bit_encoding: false,
is_match_bit: true,
new_offset_bit: true,
continue_value_bit: true,
bitstream_is_big_endian: false,
simplified_prob_update: false,
no_repeated_offsets: false,
eof_in_length: false,
max_offset: usize::MAX,
max_length: usize::MAX,
}
}
}
impl Config {
pub fn min_length(&self) -> usize {
if self.eof_in_length {
2
} else {
1
}
}
}
pub fn pack( pub fn pack(
data: &[u8], data: &[u8],
level: u8, level: u8,
config: &Config, use_bitstream: bool,
progress_callback: Option<ProgressCallback>, progress_callback: Option<ProgressCallback>,
) -> Vec<u8> { ) -> Vec<u8> {
if level == 0 { if level == 0 {
greedy_packer::pack(data, config, progress_callback) greedy_packer::pack(data, use_bitstream, progress_callback)
} else { } else {
parsing_packer::pack(data, level, config, progress_callback) parsing_packer::pack(data, level, use_bitstream, progress_callback)
} }
} }

192
src/lz.rs
View File

@@ -1,7 +1,5 @@
use crate::context_state::ContextState; use crate::context_state::ContextState;
use crate::rans::{EntropyCoder, RansDecoder}; use crate::rans::{EntropyCoder, RansDecoder};
use crate::Config;
use thiserror::Error;
#[derive(Copy, Clone, Debug)] #[derive(Copy, Clone, Debug)]
pub enum Op { pub enum Op {
@@ -10,73 +8,42 @@ pub enum Op {
} }
impl Op { impl Op {
pub fn encode(&self, coder: &mut dyn EntropyCoder, state: &mut CoderState, config: &Config) { pub fn encode(&self, coder: &mut dyn EntropyCoder, state: &mut CoderState) {
let literal_base = state.pos % state.parity_contexts * 256;
match self { match self {
&Op::Literal(lit) => { &Op::Literal(lit) => {
encode_bit(coder, state, literal_base, !config.is_match_bit); encode_bit(coder, state, 0, false);
let mut context_index = 1; let mut context_index = 1;
for i in (0..8).rev() { for i in (0..8).rev() {
let bit = (lit >> i) & 1 != 0; let bit = (lit >> i) & 1 != 0;
encode_bit(coder, state, literal_base + context_index, bit); encode_bit(coder, state, context_index, bit);
context_index = (context_index << 1) | bit as usize; context_index = (context_index << 1) | bit as usize;
} }
state.prev_was_match = false; state.prev_was_match = false;
state.pos += 1;
} }
&Op::Match { offset, len } => { &Op::Match { offset, len } => {
encode_bit(coder, state, literal_base, config.is_match_bit); encode_bit(coder, state, 0, true);
let mut new_offset = true; if !state.prev_was_match {
if !state.prev_was_match && !config.no_repeated_offsets { encode_bit(coder, state, 256, offset != state.last_offset);
new_offset = offset != state.last_offset; } else {
encode_bit( assert!(offset != state.last_offset);
coder,
state,
256 * state.parity_contexts,
new_offset == config.new_offset_bit,
);
} }
assert!(offset as usize <= config.max_offset); if offset != state.last_offset {
if new_offset { encode_length(coder, state, 257, offset + 1);
encode_length(
coder,
state,
256 * state.parity_contexts + 1,
offset + if config.eof_in_length { 0 } else { 1 },
config,
);
state.last_offset = offset; state.last_offset = offset;
} }
assert!(len as usize >= config.min_length() && len as usize <= config.max_length); encode_length(coder, state, 257 + 64, len);
encode_length(coder, state, 256 * state.parity_contexts + 65, len, config);
state.prev_was_match = true; state.prev_was_match = true;
state.pos += len as usize;
} }
} }
} }
} }
pub fn encode_eof(coder: &mut dyn EntropyCoder, state: &mut CoderState, config: &Config) { pub fn encode_eof(coder: &mut dyn EntropyCoder, state: &mut CoderState) {
encode_bit( encode_bit(coder, state, 0, true);
coder, if !state.prev_was_match {
state, encode_bit(coder, state, 256, true);
state.pos % state.parity_contexts * 256,
config.is_match_bit,
);
if !state.prev_was_match && !config.no_repeated_offsets {
encode_bit(
coder,
state,
256 * state.parity_contexts,
config.new_offset_bit ^ config.eof_in_length,
);
}
if !config.eof_in_length || state.prev_was_match || config.no_repeated_offsets {
encode_length(coder, state, 256 * state.parity_contexts + 1, 1, config);
}
if config.eof_in_length {
encode_length(coder, state, 256 * state.parity_contexts + 65, 1, config);
} }
encode_length(coder, state, 257, 1);
} }
fn encode_bit( fn encode_bit(
@@ -93,18 +60,17 @@ fn encode_length(
state: &mut CoderState, state: &mut CoderState,
context_start: usize, context_start: usize,
mut value: u32, mut value: u32,
config: &Config,
) { ) {
assert!(value >= 1); assert!(value >= 1);
let mut context_index = context_start; let mut context_index = context_start;
while value >= 2 { while value >= 2 {
encode_bit(coder, state, context_index, config.continue_value_bit); encode_bit(coder, state, context_index, true);
encode_bit(coder, state, context_index + 1, value & 1 != 0); encode_bit(coder, state, context_index + 1, value & 1 != 0);
context_index += 2; context_index += 2;
value >>= 1; value >>= 1;
} }
encode_bit(coder, state, context_index, !config.continue_value_bit); encode_bit(coder, state, context_index, false);
} }
#[derive(Clone)] #[derive(Clone)]
@@ -112,18 +78,14 @@ pub struct CoderState {
contexts: ContextState, contexts: ContextState,
last_offset: u32, last_offset: u32,
prev_was_match: bool, prev_was_match: bool,
pos: usize,
parity_contexts: usize,
} }
impl CoderState { impl CoderState {
pub fn new(config: &Config) -> CoderState { pub fn new() -> CoderState {
CoderState { CoderState {
contexts: ContextState::new((1 + 255) * config.parity_contexts + 1 + 64 + 64, config), contexts: ContextState::new(1 + 255 + 1 + 64 + 64),
last_offset: 0, last_offset: 0,
prev_was_match: false, prev_was_match: false,
pos: 0,
parity_contexts: config.parity_contexts,
} }
} }
@@ -132,141 +94,55 @@ impl CoderState {
} }
} }
#[derive(Error, Debug)] pub fn unpack(packed_data: &[u8], use_bitstream: bool) -> Vec<u8> {
pub enum UnpackError { let mut decoder = RansDecoder::new(packed_data, use_bitstream);
#[error("match offset out of range: {offset} > {position}")] let mut contexts = ContextState::new(1 + 255 + 1 + 64 + 64);
OffsetOutOfRange { offset: usize, position: usize },
#[error("Unpacked data over size limit: {size} > {limit}")]
OverSize { size: usize, limit: usize },
#[error("Unexpected end of input data")]
UnexpectedEOF {
#[from]
source: crate::rans::UnexpectedEOF,
},
#[error("Overflow while reading value")]
ValueOverflow,
}
pub fn unpack(
packed_data: &[u8],
config: &Config,
max_size: usize,
) -> Result<Vec<u8>, UnpackError> {
let mut result = vec![]; let mut result = vec![];
let _ = unpack_internal(Some(&mut result), packed_data, config, max_size)?; let mut offset = 0;
Ok(result)
}
pub fn calculate_margin(packed_data: &[u8], config: &Config) -> Result<isize, UnpackError> {
unpack_internal(None, packed_data, config, usize::MAX)
}
pub fn unpack_internal(
mut result: Option<&mut Vec<u8>>,
packed_data: &[u8],
config: &Config,
max_size: usize,
) -> Result<isize, UnpackError> {
let mut decoder = RansDecoder::new(packed_data, &config);
let mut contexts = ContextState::new((1 + 255) * config.parity_contexts + 1 + 64 + 64, &config);
let mut offset = usize::MAX;
let mut position = 0usize;
let mut prev_was_match = false; let mut prev_was_match = false;
let mut margin = 0isize;
fn decode_length( fn decode_length(
decoder: &mut RansDecoder, decoder: &mut RansDecoder,
contexts: &mut ContextState, contexts: &mut ContextState,
mut context_index: usize, mut context_index: usize,
config: &Config, ) -> usize {
) -> Result<usize, UnpackError> {
let mut length = 0; let mut length = 0;
let mut bit_pos = 0; let mut bit_pos = 0;
while decoder.decode_with_context(&mut contexts.context_mut(context_index))? while decoder.decode_with_context(&mut contexts.context_mut(context_index)) {
== config.continue_value_bit length |= (decoder.decode_with_context(&mut contexts.context_mut(context_index + 1))
{
length |= (decoder.decode_with_context(&mut contexts.context_mut(context_index + 1))?
as usize) as usize)
<< bit_pos; << bit_pos;
bit_pos += 1; bit_pos += 1;
if bit_pos >= 32 {
return Err(UnpackError::ValueOverflow);
}
context_index += 2; context_index += 2;
} }
Ok(length | (1 << bit_pos)) length | (1 << bit_pos)
} }
loop { loop {
margin = margin.max(position as isize - decoder.pos() as isize); if decoder.decode_with_context(&mut contexts.context_mut(0)) {
let literal_base = position % config.parity_contexts * 256; if prev_was_match || decoder.decode_with_context(&mut contexts.context_mut(256)) {
if decoder.decode_with_context(&mut contexts.context_mut(literal_base))? offset = decode_length(&mut decoder, &mut contexts, 257) - 1;
== config.is_match_bit
{
if config.no_repeated_offsets
|| prev_was_match
|| decoder
.decode_with_context(&mut contexts.context_mut(256 * config.parity_contexts))?
== config.new_offset_bit
{
offset = decode_length(
&mut decoder,
&mut contexts,
256 * config.parity_contexts + 1,
&config,
)? - if config.eof_in_length { 0 } else { 1 };
if offset == 0 { if offset == 0 {
break; break;
} }
} }
let length = decode_length( let length = decode_length(&mut decoder, &mut contexts, 257 + 64);
&mut decoder,
&mut contexts,
256 * config.parity_contexts + 65,
&config,
)?;
if config.eof_in_length && length == 1 {
break;
}
if offset > position {
return Err(UnpackError::OffsetOutOfRange { offset, position });
}
if let Some(ref mut result) = result {
for _ in 0..length { for _ in 0..length {
if result.len() < max_size {
result.push(result[result.len() - offset]); result.push(result[result.len() - offset]);
} else {
break;
} }
}
}
position += length;
prev_was_match = true; prev_was_match = true;
} else { } else {
let mut context_index = 1; let mut context_index = 1;
let mut byte = 0; let mut byte = 0;
for i in (0..8).rev() { for i in (0..8).rev() {
let bit = decoder let bit = decoder.decode_with_context(&mut contexts.context_mut(context_index));
.decode_with_context(&mut contexts.context_mut(literal_base + context_index))?;
context_index = (context_index << 1) | bit as usize; context_index = (context_index << 1) | bit as usize;
byte |= (bit as u8) << i; byte |= (bit as u8) << i;
} }
if let Some(ref mut result) = result {
if result.len() < max_size {
result.push(byte); result.push(byte);
}
}
position += 1;
prev_was_match = false; prev_was_match = false;
} }
} }
if position > max_size { result
return Err(UnpackError::OverSize {
size: position,
limit: max_size,
});
}
Ok(margin + decoder.pos() as isize - position as isize)
} }

View File

@@ -1,103 +1,20 @@
use anyhow::Result; use anyhow::{bail, Result};
use std::ffi::OsStr;
use std::io::prelude::*; use std::io::prelude::*;
use std::process;
use std::{fs::File, path::PathBuf}; use std::{fs::File, path::PathBuf};
fn main() -> Result<()> { fn main() -> Result<()> {
let mut config = upkr::Config::default(); let mut args = pico_args::Arguments::from_env();
let mut reverse = false;
let mut unpack = false;
let mut calculate_margin = false;
let mut level = 2;
let mut infile: Option<PathBuf> = None;
let mut outfile: Option<PathBuf> = None;
let mut max_unpacked_size = 512 * 1024 * 1024;
let mut parser = lexopt::Parser::from_env(); match args.subcommand()?.as_ref().map(|s| s.as_str()) {
while let Some(arg) = parser.next()? { None => print_help(),
use lexopt::prelude::*; Some("pack") => {
match arg { let level = args.opt_value_from_str(["-l", "--level"])?.unwrap_or(2u8);
Short('b') | Long("bitstream") => config.use_bitstream = true, let use_bitstream = args.contains(["-b", "--bitstream"]);
Short('p') | Long("parity") => config.parity_contexts = parser.value()?.parse()?, let reverse = args.contains(["-r", "--reverse"]);
Short('r') | Long("reverse") => reverse = true,
Long("invert-is-match-bit") => config.is_match_bit = false,
Long("invert-new-offset-bit") => config.new_offset_bit = false,
Long("invert-continue-value-bit") => config.continue_value_bit = false,
Long("invert-bit-encoding") => config.invert_bit_encoding = true,
Long("simplified-prob-update") => config.simplified_prob_update = true,
Long("big-endian-bitstream") => {
config.use_bitstream = true;
config.bitstream_is_big_endian = true;
}
Long("no-repeated-offsets") => config.no_repeated_offsets = true,
Long("eof-in-length") => config.eof_in_length = true,
Long("max-offset") => config.max_offset = parser.value()?.parse()?, let infile = args.free_from_os_str::<PathBuf, bool>(|s| Ok(s.into()))?;
Long("max-length") => config.max_length = parser.value()?.parse()?, let outfile = args.free_from_os_str::<PathBuf, bool>(|s| Ok(s.into()))?;
Long("z80") => {
config.use_bitstream = true;
config.bitstream_is_big_endian = true;
config.invert_bit_encoding = true;
config.simplified_prob_update = true;
level = 9;
}
Long("x86") => {
config.use_bitstream = true;
config.continue_value_bit = false;
config.is_match_bit = false;
config.new_offset_bit = false;
}
Long("x86b") => {
config.use_bitstream = true;
config.continue_value_bit = false;
config.no_repeated_offsets = true;
level = 9;
}
Short('u') | Long("unpack") => unpack = true,
Long("margin") => calculate_margin = true,
Short('l') | Long("level") => level = parser.value()?.parse()?,
Short(n) if n.is_ascii_digit() => level = n as u8 - b'0',
Short('h') | Long("help") => print_help(0),
Long("version") => {
println!("{}", env!("CARGO_PKG_VERSION"));
process::exit(0);
}
Long("max-unpacked-size") => max_unpacked_size = parser.value()?.parse()?,
Value(val) if infile.is_none() => infile = Some(val.try_into()?),
Value(val) if outfile.is_none() => outfile = Some(val.try_into()?),
_ => return Err(arg.unexpected().into()),
}
}
let infile = infile.unwrap_or_else(|| print_help(1));
let outfile = outfile.unwrap_or_else(|| {
let mut name = infile.clone();
if unpack {
if name.extension().filter(|&e| e == "upk").is_some() {
name.set_extension("");
} else {
name.set_extension("bin");
}
} else {
let mut filename = name
.file_name()
.unwrap_or_else(|| OsStr::new(""))
.to_os_string();
filename.push(".upk");
name.set_file_name(filename);
}
name
});
if config.parity_contexts != 1 && config.parity_contexts != 2 && config.parity_contexts != 4 {
eprintln!("--parity has to be 1, 2, or 4");
process::exit(1);
}
if !unpack && !calculate_margin {
let mut data = vec![]; let mut data = vec![];
File::open(infile)?.read_to_end(&mut data)?; File::open(infile)?.read_to_end(&mut data)?;
if reverse { if reverse {
@@ -109,7 +26,7 @@ fn main() -> Result<()> {
let mut packed_data = upkr::pack( let mut packed_data = upkr::pack(
&data, &data,
level, level,
&config, use_bitstream,
Some(&mut |pos| { Some(&mut |pos| {
pb.set(pos as u64); pb.set(pos as u64);
}), }),
@@ -127,64 +44,39 @@ fn main() -> Result<()> {
packed_data.len() as f32 * 100. / data.len() as f32 packed_data.len() as f32 * 100. / data.len() as f32
); );
File::create(outfile)?.write_all(&packed_data)?; File::create(outfile)?.write_all(&packed_data)?;
} else { }
Some("unpack") => {
let use_bitstream = args.contains(["-b", "--bitstream"]);
let reverse = args.contains(["-r", "--reverse"]);
let infile = args.free_from_os_str::<PathBuf, bool>(|s| Ok(s.into()))?;
let outfile = args.free_from_os_str::<PathBuf, bool>(|s| Ok(s.into()))?;
let mut data = vec![]; let mut data = vec![];
File::open(infile)?.read_to_end(&mut data)?; File::open(infile)?.read_to_end(&mut data)?;
if reverse { if reverse {
data.reverse(); data.reverse();
} }
if unpack { let mut unpacked_data = upkr::unpack(&data, use_bitstream);
let mut unpacked_data = upkr::unpack(&data, &config, max_unpacked_size)?;
if reverse { if reverse {
unpacked_data.reverse(); unpacked_data.reverse();
} }
File::create(outfile)?.write_all(&unpacked_data)?; File::create(outfile)?.write_all(&unpacked_data)?;
} }
if calculate_margin { Some(other) => {
println!("{}", upkr::calculate_margin(&data, &config)?); bail!("Unknown subcommand '{}'", other);
} }
} }
Ok(()) Ok(())
} }
fn print_help(exit_code: i32) -> ! { fn print_help() {
eprintln!("Usage:"); eprintln!("Usage:");
eprintln!(" upkr [-l level(0-9)] [config options] <infile> [<outfile>]"); eprintln!(" upkr pack [-b] [-l level(0-9)] <infile> <outfile>");
eprintln!(" upkr -u [config options] <infile> [<outfile>]"); eprintln!(" upkr unpack [-b] <infile> <outfile>");
eprintln!(" upkr --margin [config options] <infile>");
eprintln!(); eprintln!();
eprintln!(" -l, --level N compression level 0-9");
eprintln!(" -0, ..., -9 short form for setting compression level");
eprintln!(" -u, --unpack unpack infile");
eprintln!(" --margin calculate margin for overlapped unpacking of a packed file");
eprintln!();
eprintln!("Version: {}", env!("CARGO_PKG_VERSION"));
eprintln!();
eprintln!("Config presets for specific unpackers:");
eprintln!(" --z80 --big-endian-bitstream --invert-bit-encoding --simplified-prob-update -9");
eprintln!(
" --x86 --bitstream --invert-is-match-bit --invert-continue-value-bit --invert-new-offset-bit"
);
eprintln!(
" --x86b --bitstream --invert-continue-value-bit --no-repeated-offsets -9"
);
eprintln!();
eprintln!("Config options (need to match when packing/unpacking):");
eprintln!(" -b, --bitstream bitstream mode"); eprintln!(" -b, --bitstream bitstream mode");
eprintln!(" -p, --parity N use N (2/4) parity contexts"); eprintln!(" -l, --level N compression level 0-9");
eprintln!(" -r, --reverse reverse input & output"); std::process::exit(1);
eprintln!();
eprintln!("Config options to tailor output to specific optimized unpackers:");
eprintln!(" --invert-is-match-bit");
eprintln!(" --invert-new-offset-bit");
eprintln!(" --invert-continue-value-bit");
eprintln!(" --invert-bit-encoding");
eprintln!(" --simplified-prob-update");
eprintln!(" --big-endian-bitstream (implies --bitstream)");
eprintln!(" --no-repeated-offsets");
eprintln!(" --eof-in-length");
eprintln!(" --max-offset N");
eprintln!(" --max-length N");
process::exit(exit_code);
} }

View File

@@ -6,24 +6,19 @@ use crate::match_finder::MatchFinder;
use crate::rans::{CostCounter, RansCoder}; use crate::rans::{CostCounter, RansCoder};
use crate::{lz, ProgressCallback}; use crate::{lz, ProgressCallback};
pub fn pack( pub fn pack(data: &[u8], level: u8, use_bitstream: bool, progress_cb: Option<ProgressCallback>) -> Vec<u8> {
data: &[u8], let mut parse = parse(data, Config::from_level(level), progress_cb);
level: u8,
config: &crate::Config,
progress_cb: Option<ProgressCallback>,
) -> Vec<u8> {
let mut parse = parse(data, Config::from_level(level), config, progress_cb);
let mut ops = vec![]; let mut ops = vec![];
while let Some(link) = parse { while let Some(link) = parse {
ops.push(link.op); ops.push(link.op);
parse = link.prev.clone(); parse = link.prev.clone();
} }
let mut state = lz::CoderState::new(config); let mut state = lz::CoderState::new();
let mut coder = RansCoder::new(config); let mut coder = RansCoder::new(use_bitstream);
for op in ops.into_iter().rev() { for op in ops.into_iter().rev() {
op.encode(&mut coder, &mut state, config); op.encode(&mut coder, &mut state);
} }
lz::encode_eof(&mut coder, &mut state, config); lz::encode_eof(&mut coder, &mut state);
coder.finish() coder.finish()
} }
@@ -43,7 +38,6 @@ type Arrivals = HashMap<usize, Vec<Arrival>>;
fn parse( fn parse(
data: &[u8], data: &[u8],
config: Config, config: Config,
encoding_config: &crate::Config,
mut progress_cb: Option<ProgressCallback>, mut progress_cb: Option<ProgressCallback>,
) -> Option<Rc<Parse>> { ) -> Option<Rc<Parse>> {
let mut match_finder = MatchFinder::new(data) let mut match_finder = MatchFinder::new(data)
@@ -105,22 +99,17 @@ fn parse(
cost_counter: &mut CostCounter, cost_counter: &mut CostCounter,
pos: usize, pos: usize,
offset: usize, offset: usize,
mut length: usize, length: usize,
arrival: &Arrival, arrival: &Arrival,
max_arrivals: usize, max_arrivals: usize,
config: &crate::Config,
) { ) {
if length < config.min_length() {
return;
}
length = length.min(config.max_length);
cost_counter.reset(); cost_counter.reset();
let mut state = arrival.state.clone(); let mut state = arrival.state.clone();
let op = lz::Op::Match { let op = lz::Op::Match {
offset: offset as u32, offset: offset as u32,
len: length as u32, len: length as u32,
}; };
op.encode(cost_counter, &mut state, config); op.encode(cost_counter, &mut state);
add_arrival( add_arrival(
arrivals, arrivals,
pos + length, pos + length,
@@ -140,13 +129,13 @@ fn parse(
0, 0,
Arrival { Arrival {
parse: None, parse: None,
state: lz::CoderState::new(encoding_config), state: lz::CoderState::new(),
cost: 0.0, cost: 0.0,
}, },
max_arrivals, max_arrivals,
); );
let cost_counter = &mut CostCounter::new(encoding_config); let cost_counter = &mut CostCounter::new();
let mut best_per_offset = HashMap::new(); let mut best_per_offset = HashMap::new();
for pos in 0..data.len() { for pos in 0..data.len() {
let match_length = |offset: usize| { let match_length = |offset: usize| {
@@ -187,7 +176,6 @@ fn parse(
for m in match_finder.matches(pos) { for m in match_finder.matches(pos) {
closest_match = Some(closest_match.unwrap_or(0).max(m.pos)); closest_match = Some(closest_match.unwrap_or(0).max(m.pos));
let offset = pos - m.pos; let offset = pos - m.pos;
if offset <= encoding_config.max_offset {
found_last_offset |= offset as u32 == arrival.state.last_offset(); found_last_offset |= offset as u32 == arrival.state.last_offset();
add_match( add_match(
&mut arrivals, &mut arrivals,
@@ -197,13 +185,11 @@ fn parse(
m.length, m.length,
&arrival, &arrival,
max_arrivals, max_arrivals,
encoding_config,
); );
if m.length >= config.greedy_size { if m.length >= config.greedy_size {
break 'arrival_loop; break 'arrival_loop;
} }
} }
}
let mut near_matches_left = config.num_near_matches; let mut near_matches_left = config.num_near_matches;
let mut match_pos = last_seen[data[pos] as usize]; let mut match_pos = last_seen[data[pos] as usize];
@@ -212,9 +198,6 @@ fn parse(
&& closest_match.iter().all(|p| *p < match_pos) && closest_match.iter().all(|p| *p < match_pos)
{ {
let offset = pos - match_pos; let offset = pos - match_pos;
if offset > encoding_config.max_offset {
break;
}
let length = match_length(offset); let length = match_length(offset);
assert!(length > 0); assert!(length > 0);
add_match( add_match(
@@ -225,7 +208,6 @@ fn parse(
length, length,
&arrival, &arrival,
max_arrivals, max_arrivals,
encoding_config,
); );
found_last_offset |= offset as u32 == arrival.state.last_offset(); found_last_offset |= offset as u32 == arrival.state.last_offset();
if offset < near_matches.len() { if offset < near_matches.len() {
@@ -246,7 +228,6 @@ fn parse(
length, length,
&arrival, &arrival,
max_arrivals, max_arrivals,
encoding_config,
); );
} }
} }
@@ -254,7 +235,7 @@ fn parse(
cost_counter.reset(); cost_counter.reset();
let mut state = arrival.state; let mut state = arrival.state;
let op = lz::Op::Literal(data[pos]); let op = lz::Op::Literal(data[pos]);
op.encode(cost_counter, &mut state, encoding_config); op.encode(cost_counter, &mut state);
add_arrival( add_arrival(
&mut arrivals, &mut arrivals,
pos + 1, pos + 1,

View File

@@ -1,5 +1,4 @@
use crate::{context_state::Context, Config}; use crate::context_state::Context;
use thiserror::Error;
pub const PROB_BITS: u32 = 8; pub const PROB_BITS: u32 = 8;
pub const ONE_PROB: u32 = 1 << PROB_BITS; pub const ONE_PROB: u32 = 1 << PROB_BITS;
@@ -16,25 +15,20 @@ pub trait EntropyCoder {
pub struct RansCoder { pub struct RansCoder {
bits: Vec<u16>, bits: Vec<u16>,
use_bitstream: bool, use_bitstream: bool,
bitstream_is_big_endian: bool,
invert_bit_encoding: bool,
} }
impl EntropyCoder for RansCoder { impl EntropyCoder for RansCoder {
fn encode_bit(&mut self, bit: bool, prob: u16) { fn encode_bit(&mut self, bit: bool, prob: u16) {
assert!(prob < 32768); assert!(prob < 32768);
self.bits self.bits.push(prob | ((bit as u16) << 15));
.push(prob | (((bit ^ self.invert_bit_encoding) as u16) << 15));
} }
} }
impl RansCoder { impl RansCoder {
pub fn new(config: &Config) -> RansCoder { pub fn new(use_bitstream: bool) -> RansCoder {
RansCoder { RansCoder {
bits: Vec::new(), bits: Vec::new(),
use_bitstream: config.use_bitstream, use_bitstream,
bitstream_is_big_endian: config.bitstream_is_big_endian,
invert_bit_encoding: config.invert_bit_encoding,
} }
} }
@@ -44,9 +38,8 @@ impl RansCoder {
let mut state = 1 << l_bits; let mut state = 1 << l_bits;
let mut byte = 0u8; let mut byte = 0u8;
let mut bit = if self.bitstream_is_big_endian { 0 } else { 8 }; let mut bit = 0;
let mut flush_state: Box<dyn FnMut(&mut u32)> = if self.use_bitstream { let mut flush_state: Box<dyn FnMut(&mut u32)> = if self.use_bitstream {
if self.bitstream_is_big_endian {
Box::new(|state: &mut u32| { Box::new(|state: &mut u32| {
byte |= ((*state & 1) as u8) << bit; byte |= ((*state & 1) as u8) << bit;
bit += 1; bit += 1;
@@ -57,18 +50,6 @@ impl RansCoder {
} }
*state >>= 1; *state >>= 1;
}) })
} else {
Box::new(|state: &mut u32| {
bit -= 1;
byte |= ((*state & 1) as u8) << bit;
if bit == 0 {
buffer.push(byte);
byte = 0;
bit = 8;
}
*state >>= 1;
})
}
} else { } else {
Box::new(|state: &mut u32| { Box::new(|state: &mut u32| {
buffer.push(*state as u8); buffer.push(*state as u8);
@@ -80,7 +61,7 @@ impl RansCoder {
let max_state_factor: u32 = 1 << (l_bits + num_flush_bits - PROB_BITS); let max_state_factor: u32 = 1 << (l_bits + num_flush_bits - PROB_BITS);
for step in self.bits.into_iter().rev() { for step in self.bits.into_iter().rev() {
let prob = step as u32 & 32767; let prob = step as u32 & 32767;
let (start, prob) = if step & 32768 != 0 { let (start, prob) = if step & 32768 == 0 {
(0, prob) (0, prob)
} else { } else {
(prob, ONE_PROB - prob) (prob, ONE_PROB - prob)
@@ -110,11 +91,10 @@ impl RansCoder {
pub struct CostCounter { pub struct CostCounter {
cost: f64, cost: f64,
log2_table: Vec<f64>, log2_table: Vec<f64>,
invert_bit_encoding: bool,
} }
impl CostCounter { impl CostCounter {
pub fn new(config: &Config) -> CostCounter { pub fn new() -> CostCounter {
let log2_table = (0..ONE_PROB) let log2_table = (0..ONE_PROB)
.map(|prob| { .map(|prob| {
let inv_prob = ONE_PROB as f64 / prob as f64; let inv_prob = ONE_PROB as f64 / prob as f64;
@@ -124,7 +104,6 @@ impl CostCounter {
CostCounter { CostCounter {
cost: 0.0, cost: 0.0,
log2_table, log2_table,
invert_bit_encoding: config.invert_bit_encoding,
} }
} }
@@ -139,7 +118,7 @@ impl CostCounter {
impl EntropyCoder for CostCounter { impl EntropyCoder for CostCounter {
fn encode_bit(&mut self, bit: bool, prob: u16) { fn encode_bit(&mut self, bit: bool, prob: u16) {
let prob = if bit ^ self.invert_bit_encoding { let prob = if !bit {
prob as u32 prob as u32
} else { } else {
ONE_PROB - prob as u32 ONE_PROB - prob as u32
@@ -150,85 +129,60 @@ impl EntropyCoder for CostCounter {
pub struct RansDecoder<'a> { pub struct RansDecoder<'a> {
data: &'a [u8], data: &'a [u8],
pos: usize,
state: u32, state: u32,
use_bitstream: bool, use_bitstream: bool,
byte: u8, byte: u8,
bits_left: u8, bits_left: u8,
invert_bit_encoding: bool,
bitstream_is_big_endian: bool,
} }
const PROB_MASK: u32 = ONE_PROB - 1; const PROB_MASK: u32 = ONE_PROB - 1;
#[derive(Debug, Error)]
#[error("Unexpected end of input")]
pub struct UnexpectedEOF;
impl<'a> RansDecoder<'a> { impl<'a> RansDecoder<'a> {
pub fn new(data: &'a [u8], config: &Config) -> RansDecoder<'a> { pub fn new(data: &'a [u8], use_bitstream: bool) -> RansDecoder<'a> {
RansDecoder { RansDecoder {
data, data,
pos: 0,
state: 0, state: 0,
use_bitstream: config.use_bitstream, use_bitstream,
byte: 0, byte: 0,
bits_left: 0, bits_left: 0,
invert_bit_encoding: config.invert_bit_encoding,
bitstream_is_big_endian: config.bitstream_is_big_endian,
} }
} }
pub fn pos(&self) -> usize { pub fn decode_with_context(&mut self, context: &mut Context) -> bool {
self.pos let bit = self.decode_bit(context.prob());
}
pub fn decode_with_context(&mut self, context: &mut Context) -> Result<bool, UnexpectedEOF> {
let bit = self.decode_bit(context.prob())?;
context.update(bit); context.update(bit);
Ok(bit) bit
} }
pub fn decode_bit(&mut self, prob: u16) -> Result<bool, UnexpectedEOF> { pub fn decode_bit(&mut self, prob: u16) -> bool {
let prob = prob as u32; let prob = prob as u32;
if self.use_bitstream { if self.use_bitstream {
while self.state < 32768 { while self.state < 32768 {
if self.bits_left == 0 { if self.bits_left == 0 {
if self.pos >= self.data.len() { self.byte = self.data[0];
return Err(UnexpectedEOF); self.data = &self.data[1..];
}
self.byte = self.data[self.pos];
self.pos += 1;
self.bits_left = 8; self.bits_left = 8;
} }
if self.bitstream_is_big_endian {
self.state = (self.state << 1) | (self.byte >> 7) as u32; self.state = (self.state << 1) | (self.byte >> 7) as u32;
self.byte <<= 1; self.byte <<= 1;
} else {
self.state = (self.state << 1) | (self.byte & 1) as u32;
self.byte >>= 1;
}
self.bits_left -= 1; self.bits_left -= 1;
} }
} else { } else {
while self.state < 4096 { while self.state < 4096 {
if self.pos >= self.data.len() { self.state = (self.state << 8) | self.data[0] as u32;
return Err(UnexpectedEOF); self.data = &self.data[1..];
}
self.state = (self.state << 8) | self.data[self.pos] as u32;
self.pos += 1;
} }
} }
let bit = (self.state & PROB_MASK) < prob; let bit = (self.state & PROB_MASK) >= prob;
let (start, prob) = if bit { let (start, prob) = if bit {
(0, prob)
} else {
(prob, ONE_PROB - prob) (prob, ONE_PROB - prob)
} else {
(0, prob)
}; };
self.state = prob * (self.state >> PROB_BITS) + (self.state & PROB_MASK) - start; self.state = prob * (self.state >> PROB_BITS) + (self.state & PROB_MASK) - start;
Ok(bit ^ self.invert_bit_encoding) bit
} }
} }