first (poorly optimized) risc-v unpacker

Cargo.lock

@@ -62,6 +62,12 @@ version = "1.4.0"
 source = "registry+https://github.com/rust-lang/crates.io-index"
 checksum = "e2abad23fbc42b3700f2f279844dc832adb2b2eb069b2df918f455c4e18cc646"
 
+[[package]]
+name = "lexopt"
+version = "0.2.1"
+source = "registry+https://github.com/rust-lang/crates.io-index"
+checksum = "478ee9e62aaeaf5b140bd4138753d1f109765488581444218d3ddda43234f3e8"
+
 [[package]]
 name = "libc"
 version = "0.2.108"
@@ -89,12 +95,6 @@ dependencies = [
  "winapi",
 ]
 
-[[package]]
-name = "pico-args"
-version = "0.4.2"
-source = "registry+https://github.com/rust-lang/crates.io-index"
-checksum = "db8bcd96cb740d03149cbad5518db9fd87126a10ab519c011893b1754134c468"
-
 [[package]]
 name = "sacabase"
 version = "2.0.0"
@@ -121,8 +121,8 @@ version = "0.1.0"
 dependencies = [
  "anyhow",
  "cdivsufsort",
+ "lexopt",
  "pbr",
- "pico-args",
 ]
 
 [[package]]

Cargo.toml

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

asm_unpackers/Makefile

@@ -1,4 +1,4 @@
-build/unpack_riscv64: ../c_unpacker/main.c ../c_unpacker/unpack.c
+build/unpack_riscv64: ../c_unpacker/main.c unpack_riscv.S
 	mkdir -p build
 	riscv64-linux-gnu-gcc -g -static -o $@ $^
 
@@ -6,6 +6,11 @@ test_riscv64: build/unpack_riscv64
 	qemu-riscv64 $< test_data.upk /tmp/out.bin
 	cmp test_data.bin /tmp/out.bin
 
+build/unpack_riscv64.bin: unpack_riscv.S
+	mkdir -p build
+	riscv64-linux-gnu-gcc -c -o build/unpack_riscv64.o $?
+	riscv64-linux-gnu-objcopy -O binary --only-section=.text build/unpack_riscv64.o $@
+
 build/unpack_armv6m: ../c_unpacker/main.c unpack_armv6m.S
 	mkdir -p build
 	arm-linux-gnueabihf-gcc -g -static -o $@ $^
@@ -15,6 +20,7 @@ test_armv6m: build/unpack_armv6m
 	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 $@
 	
@@ -26,5 +32,5 @@ test_c: build/unpack_c
 	$< test_data.upk /tmp/out.bin
 	cmp test_data.bin /tmp/out.bin
 
-sizes: build/unpack_armv6m.bin
+sizes: build/unpack_armv6m.bin build/unpack_riscv64.bin
 	ls -l build/*.bin

asm_unpackers/unpack_riscv.S

@@ -0,0 +1,144 @@
+.section .text
+
+#define FRAME_SIZE (256+64*4+4)
+
+// x8 prob array ptr
+// x9 prev was literal
+// x10 out ptr
+// x11 in ptr
+// x12 offset
+// x13 state
+
+.global upkr_unpack
+.type upkr_unpack, %function
+upkr_unpack:
+	mv t4, ra
+	mv x17, x8
+	mv t6, x9
+	li x13, FRAME_SIZE
+	li x9, 128
+1:
+	addi sp, sp, -1
+	sb x9, 0(sp)
+	addi x13, x13, -1
+	bnez x13, 1b
+	
+.Lmainloop:
+	li x14, 0
+	jal upkr_decode_bit
+	beqz x15, .Lliteral
+	
+	li x14, 256
+	beqz x9, .Lread_offset
+	jal upkr_decode_bit
+	beqz x15, .Lskip_offset
+.Lread_offset:
+	jal t3, upkr_decode_number
+	addi x12, x9, -1
+	beqz x12, .Ldone
+
+.Lskip_offset:
+	li x14, 256+64
+	jal t3, upkr_decode_number
+1:
+	sub x15, x10, x12
+	lbu x15, (x15)
+	sb x15, (x10)
+	addi x10, x10, 1
+	addi x9, x9, -1
+	bnez x9, 1b
+	j .Lmainloop
+	
+.Lliteral:
+	li x14, 1
+1:
+	jal upkr_decode_bit
+	slli x14, x14, 1
+	add x14, x14, x15
+	srli x9, x14, 8
+	beqz x9, 1b
+	sb x14, 0(x10)
+	addi x10, x10, 1
+	j .Lmainloop
+
+.Ldone:
+	addi sp, sp, FRAME_SIZE
+	mv x8, x17
+	mv x9, t6
+	jr t4
+
+// x14 context index
+// return: x9 decoded number 
+upkr_decode_number:
+	mv t5, x14
+	li x9, 0
+	li x8, 1
+1:
+	addi x14, x14, 1
+	jal upkr_decode_bit
+	beqz x15, 1f
+	addi x14, x14, 1
+	jal upkr_decode_bit
+	beqz x15, 2f
+	add x9, x9, x8
+2:
+	slli x8, x8, 1
+	j 1b
+1:
+	add x9, x9, x8
+	
+	mv x14, t5
+	jr t3
+
+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: x15 decoded bit
+upkr_decode_bit:
+	srli x15, x13, 12
+	beqz x15, upkr_load_byte
+
+	mv t0, x9
+	mv t1, x14
+	mv t2, x10
+	
+	add x14, x14, sp
+	lbu x9, 0(x14)
+	
+	andi x10, x13, 255
+	sltu x15, x10, x9
+	srli x13, x13, 8
+	beqz x15, .Lelse
+	
+	mul x13, x13, x9
+	add x13, x13, x10
+	li x10, 256 + 8
+	sub x10, x10, x9
+	srli x10, x10, 4
+	add x9, x9, x10
+	j .Lendif
+
+.Lelse:
+	li x16, 256
+	sub x16, x16, x9
+	mul x13, x13, x16
+	add x13, x13, x10
+	sub x13, x13, x9
+	addi x10, x9, 8
+	srli x10, x10, 4
+	sub x9, x9, x10
+
+.Lendif:
+
+	sb x9, 0(x14)
+	
+	mv x9, t0
+	mv x14, t1
+	mv x10, t2
+	ret

src/lib.rs

@@ -9,21 +9,39 @@ pub use lz::unpack;
 
 pub type ProgressCallback<'a> = &'a mut dyn FnMut(usize);
 
+pub struct Config {
+    pub use_bitstream: bool,
+    pub parity_contexts: usize,
+}
+
+impl Default for Config {
+    fn default() -> Config {
+        Config {
+            use_bitstream: false,
+            parity_contexts: 1,
+        }
+    }
+}
+
 pub fn pack(
     data: &[u8],
     level: u8,
-    use_bitstream: bool,
-    parity_contexts: usize,
+    config: Config,
     progress_callback: Option<ProgressCallback>,
 ) -> Vec<u8> {
     if level == 0 {
-        greedy_packer::pack(data, use_bitstream, parity_contexts, progress_callback)
+        greedy_packer::pack(
+            data,
+            config.use_bitstream,
+            config.parity_contexts,
+            progress_callback,
+        )
     } else {
         parsing_packer::pack(
             data,
             level,
-            use_bitstream,
-            parity_contexts,
+            config.use_bitstream,
+            config.parity_contexts,
             progress_callback,
         )
     }

src/lz.rs

@@ -106,9 +106,9 @@ impl CoderState {
     }
 }
 
-pub fn unpack(packed_data: &[u8], use_bitstream: bool, parity_contexts: usize) -> Vec<u8> {
-    let mut decoder = RansDecoder::new(packed_data, use_bitstream);
-    let mut contexts = ContextState::new((1 + 255) * parity_contexts + 1 + 64 + 64);
+pub fn unpack(packed_data: &[u8], config: crate::Config) -> Vec<u8> {
+    let mut decoder = RansDecoder::new(packed_data, config.use_bitstream);
+    let mut contexts = ContextState::new((1 + 255) * config.parity_contexts + 1 + 64 + 64);
     let mut result = vec![];
     let mut offset = 0;
     let mut prev_was_match = false;
@@ -131,17 +131,26 @@ pub fn unpack(packed_data: &[u8], use_bitstream: bool, parity_contexts: usize) -
     }
 
     loop {
-        let literal_base = result.len() % parity_contexts * 256;
+        let literal_base = result.len() % config.parity_contexts * 256;
         if decoder.decode_with_context(&mut contexts.context_mut(literal_base)) {
             if prev_was_match
-                || decoder.decode_with_context(&mut contexts.context_mut(256 * parity_contexts))
+                || decoder
+                    .decode_with_context(&mut contexts.context_mut(256 * config.parity_contexts))
             {
-                offset = decode_length(&mut decoder, &mut contexts, 256 * parity_contexts + 1) - 1;
+                offset = decode_length(
+                    &mut decoder,
+                    &mut contexts,
+                    256 * config.parity_contexts + 1,
+                ) - 1;
                 if offset == 0 {
                     break;
                 }
             }
-            let length = decode_length(&mut decoder, &mut contexts, 256 * parity_contexts + 65);
+            let length = decode_length(
+                &mut decoder,
+                &mut contexts,
+                256 * config.parity_contexts + 65,
+            );
             for _ in 0..length {
                 result.push(result[result.len() - offset]);
             }

src/main.rs

@@ -1,44 +1,81 @@
-use anyhow::{bail, Result};
+use anyhow::Result;
+use std::ffi::OsStr;
 use std::io::prelude::*;
 use std::process;
 use std::{fs::File, path::PathBuf};
 
 fn main() -> Result<()> {
-    let mut args = pico_args::Arguments::from_env();
+    let mut config = upkr::Config::default();
+    let mut reverse = false;
+    let mut unpack = false;
+    let mut level = 2;
+    let mut infile: Option<PathBuf> = None;
+    let mut outfile: Option<PathBuf> = None;
 
-    match args.subcommand()?.as_ref().map(|s| s.as_str()) {
-        None => print_help(),
-        Some("pack") => {
-            let level = args.opt_value_from_str(["-l", "--level"])?.unwrap_or(2u8);
-            let use_bitstream = args.contains(["-b", "--bitstream"]);
-            let parity_contexts = args
-                .opt_value_from_str(["-p", "--parity"])?
-                .unwrap_or(1usize);
+    let mut parser = lexopt::Parser::from_env();
+    while let Some(arg) = parser.next()? {
+        use lexopt::prelude::*;
+        match arg {
+            Short('b') | Long("bitstream") => config.use_bitstream = true,
+            Short('p') | Long("parity") => config.parity_contexts = parser.value()?.parse()?,
+            Short('r') | Long("reverse") => reverse = true,
+            Short('u') | Long("unpack") => unpack = true,
+            Short('l') | Long("level") => level = parser.value()?.parse()?,
+            Short('h') | Long("help") => print_help(0),
+            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()),
+        }
+    }
 
-            if parity_contexts != 1 && parity_contexts != 2 && parity_contexts != 4 {
-                eprintln!("--parity has to be 1, 2 or 4");
+    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);
     }
 
-            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()))?;
-
+    if !unpack {
         let mut data = vec![];
         File::open(infile)?.read_to_end(&mut data)?;
+        if reverse {
+            data.reverse();
+        }
 
         let mut pb = pbr::ProgressBar::new(data.len() as u64);
         pb.set_units(pbr::Units::Bytes);
-            let packed_data = upkr::pack(
+        let mut packed_data = upkr::pack(
             &data,
             level,
-                use_bitstream,
-                parity_contexts,
+            config,
             Some(&mut |pos| {
                 pb.set(pos as u64);
             }),
         );
         pb.finish();
 
+        if reverse {
+            packed_data.reverse();
+        }
+
         println!(
             "Compressed {} bytes to {} bytes ({}%)",
             data.len(),
@@ -46,41 +83,33 @@ fn main() -> Result<()> {
             packed_data.len() as f32 * 100. / data.len() as f32
         );
         File::create(outfile)?.write_all(&packed_data)?;
-        }
-        Some("unpack") => {
-            let use_bitstream = args.contains(["-b", "--bitstream"]);
-            let parity_contexts = args
-                .opt_value_from_str(["-p", "--parity"])?
-                .unwrap_or(1usize);
-
-            if parity_contexts != 1 && parity_contexts != 2 && parity_contexts != 4 {
-                eprintln!("--parity has to be 1, 2 or 4");
-                process::exit(1);
-            }
-
-            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()))?;
-
+    } else {
         let mut data = vec![];
         File::open(infile)?.read_to_end(&mut data)?;
-            let packed_data = upkr::unpack(&data, use_bitstream, parity_contexts);
-            File::create(outfile)?.write_all(&packed_data)?;
+        if reverse {
+            data.reverse();
         }
-        Some(other) => {
-            bail!("Unknown subcommand '{}'", other);
+        let mut unpacked_data = upkr::unpack(&data, config);
+        if reverse {
+            unpacked_data.reverse();
         }
+        File::create(outfile)?.write_all(&unpacked_data)?;
     }
 
     Ok(())
 }
 
-fn print_help() {
+fn print_help(exit_code: i32) -> ! {
     eprintln!("Usage:");
-    eprintln!("  upkr pack [-b] [-l level(0-9)] [-p N] <infile> <outfile>");
-    eprintln!("  upkr unpack [-b] [-p N] <infile> <outfile>");
+    eprintln!("  upkr [-l level(0-9)] [config options] <infile> [<outfile>]");
+    eprintln!("  upkr -u [config options] <infile> [<outfile>]");
     eprintln!();
-    eprintln!(" -b, --bitstream     bitstream mode");
     eprintln!(" -l, --level N       compression level 0-9");
+    eprintln!(" -u, --unpack        unpack infile");
+    eprintln!();
+    eprintln!("Config options (need to match when packing/unpacking):");
+    eprintln!(" -b, --bitstream     bitstream mode");
     eprintln!(" -p, --parity N      use N (2/4) parity contexts");
-    process::exit(1);
+    eprintln!(" -r, --reverse       reverse input & output");
+    process::exit(exit_code);
 }