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Renamed function table's comments to inline comments and added block comments.

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Found some of C's standard library functions.
Added random functions found.
`dcb-decompiler` will now properly align inline comments.
This commit is contained in:
Filipe Rodrigues 2021-04-18 23:12:32 +01:00
parent 68c76a7f03
commit 6c2de4fd80
6 changed files with 473 additions and 29 deletions
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4
dcb-exe/src/func.rs
View File

@ -30,6 +30,10 @@ pub struct Func {
#[serde(default)]
pub desc: String,
/// Inline Comments
#[serde(default)]
pub inline_comments: BTreeMap<Pos, String>,
/// Comments
#[serde(default)]
pub comments: BTreeMap<Pos, String>,

1
dcb-exe/src/func/table.rs
View File

@ -179,6 +179,7 @@ impl FuncTable {
name: format!("func_{idx}"),
signature: "fn()".to_owned(),
desc: String::new(),
inline_comments: BTreeMap::new(),
comments: BTreeMap::new(),
labels,
start_pos: func_pos,

14
dcb-tools/dcb-compiler/src/main.rs
View File

@ -7,6 +7,8 @@ mod cli;
// Imports
use anyhow::Context;
use dcb_exe::inst::parse::InstParser;
use std::io::Write;
fn main() -> Result<(), anyhow::Error> {
// Initialize the logger
@ -17,10 +19,16 @@ fn main() -> Result<(), anyhow::Error> {
let cli = cli::CliData::new();
// Open the input and output file
let _input_file = std::fs::File::open(&cli.input_path).context("Unable to open input file")?;
let _output_file = std::fs::File::open(&cli.output_file_path).context("Unable to open output file")?;
let input_file = std::fs::File::open(&cli.input_path).context("Unable to open input file")?;
let mut output_file = std::fs::File::create(&cli.output_file_path).context("Unable to open output file")?;
// Read the executable
// Read the input
let parser = InstParser::new(input_file);
// For each instruction, output it
for inst in parser {
writeln!(output_file, "{:?}", inst).context("Unable to write to output file")?;
}
/*
let exe = Exe::new();

102
dcb-tools/dcb-decompiler/src/main.rs
View File

@ -1,6 +1,14 @@
//! Decompiler
#![feature(box_syntax, backtrace, panic_info_message, array_chunks, format_args_capture, bindings_after_at)]
#![feature(
box_syntax,
backtrace,
panic_info_message,
array_chunks,
format_args_capture,
bindings_after_at,
iter_map_while
)]
// Modules
mod cli;
@ -12,7 +20,7 @@ use dcb_exe::{
reader::iter::ExeItem,
ExeReader, Func, Pos,
};
use std::fmt;
use std::{collections::BTreeMap, fmt};
fn main() -> Result<(), anyhow::Error> {
// Initialize the logger
@ -33,10 +41,19 @@ fn main() -> Result<(), anyhow::Error> {
println!("Header:\n{}", exe.header());
}
// Instruction buffers
let mut inst_buffers: BTreeMap<Pos, String> = BTreeMap::new();
// If currently in an inline-comment alignment
let mut cur_inline_comment_alignment_max_inst_len: Option<usize> = None;
for item in exe.iter() {
match item {
// For each function or header, print a header and all it's instructions
ExeItem::Func { func, insts } => {
// Drop any old instruction buffers
inst_buffers = inst_buffers.split_off(&func.start_pos);
println!("\n##########");
println!("{}:", func.name);
if !func.signature.is_empty() {
@ -45,22 +62,91 @@ fn main() -> Result<(), anyhow::Error> {
for description in func.desc.lines() {
println!("# {description}");
}
for (pos, inst) in insts {
let insts: Vec<_> = insts.collect();
for (cur_n, (pos, inst)) in insts.iter().enumerate() {
// If there's a comment, print it
if let Some(comment) = func.comments.get(pos) {
// Iterate over the lines in the comment
for line in comment.lines() {
println!("# {line}");
}
}
// If there's a label, print it
if let Some(label) = func.labels.get(&pos) {
if let Some(label) = func.labels.get(pos) {
println!("\t.{label}:");
}
// If we don't have a comment, remove the current alignment
if !func.inline_comments.contains_key(&pos) {
cur_inline_comment_alignment_max_inst_len = None;
}
// If we don't have any alignment padding, and this instruction and the next have inline comments,
// set the inline alignment
if cur_inline_comment_alignment_max_inst_len.is_none() &&
func.inline_comments.contains_key(&pos) &&
func.inline_comments.contains_key(&(pos + 4))
{
let max_inst_len = (0..)
.map_while(|n| {
// If the next instruction doesn't have a comment, return
let offset = 4 * n;
let pos = pos + offset;
if !func.inline_comments.contains_key(&pos) {
return None;
}
// Then build the instruction
let inst = &insts.get(cur_n + n)?.1;
let inst = inst_buffers
.entry(pos)
.or_insert_with(|| self::inst_display(inst, &exe, Some(func), pos).to_string());
let inst_len = inst.len();
Some(inst_len)
})
.max()
.expect("Next instruction had an inline comment");
cur_inline_comment_alignment_max_inst_len = Some(max_inst_len);
}
// Write the position
if cli.print_inst_pos {
print!("{pos}:");
}
// Write the instruction
print!("\t{}", self::inst_display(&inst, &exe, Some(func), pos));
// If we have the instruction buffer, pop it and use it
match inst_buffers.get(&pos) {
Some(inst) => print!("\t{inst}"),
None => print!("\t{}", self::inst_display(&inst, &exe, Some(func), *pos)),
}
// If there's an inline comment, print it
if let Some(comment) = func.inline_comments.get(&pos) {
// Replace any newlines with '\n'
let modified_comment;
let comment = match comment.contains('\n') {
true => {
modified_comment = comment.replace("\n", "\\n");
&modified_comment
},
false => comment,
};
// If we have alignment padding, apply it
if let Some(max_inst_len) = cur_inline_comment_alignment_max_inst_len {
let inst = inst_buffers
.get(&pos)
.expect("Instruction wasn't in buffer during inline comment alignment");
let padding = max_inst_len - inst.len();
for _ in 0..padding {
print!(" ");
}
}
// If there's a comment, print it
if let Some(comment) = func.comments.get(&pos) {
print!(" # {comment}");
}

10
resources/game_data.yaml
View File

@ -84,6 +84,11 @@
pos: 0x80077a08
ty: u32
kind: Known
- name: cur_prng_value
desc: Current prng value
pos: 0x801ddc10
ty: u32
kind: Known
- name: HeapStart
desc: Start of the heap
pos: 0x801ddf38
@ -122,7 +127,10 @@
kind: Known
- name: FuncList1
pos: 0x80070a88
ty: u32
ty:
Array:
ty: u32
len: 8
kind: Known
- name: FuncList1Ptr
desc: Pointer to FuncList1

371
resources/game_funcs.yaml
View File

@ -3,7 +3,7 @@
- name: start
signature: fn() -> !
desc: Executable start
comments:
inline_comments:
0x80056280: Zero out ZeroStart .. HeapStart word by word.
0x80056284: ^
0x80056288: ^
@ -22,7 +22,7 @@
signature: fn() -> !
desc: Runs the main loop of the game.
Never seems to return.
comments:
inline_comments:
0x80013e50: The return address is stored, but it seems it's never popped.
0x80013e54: Just sets `something1_executed` to 1.
0x80013e5c: Setup interrupts and DMA and possibly other stuff.
@ -43,7 +43,7 @@
desc: If something1_executed is 0, sets it to 1.
Also calls `call_func_arr(something1_data2, something1_data2)` if 0,
but this seems to be a nop.
comments:
inline_comments:
0x80056348: If *something1_executed != 0, skip
0x80056350: Else set it to 1.
0x80056368: "args: (something1_data2, something1_data2). Seems like a nop?"
@ -59,7 +59,7 @@
After running the game for a bit it doesn't seem to be triggered,
all the way from the start of a new game to the battle arena fight.
signature: "fn(start: *fn(), end: *fn())"
comments:
inline_comments:
0x800563a0: If `start >= end`, return
0x800563a8: Load the current function
0x800563b0: If it was null, skip the call.
@ -77,7 +77,7 @@
- name: something3
signature: fn()
desc: Calls `something5`.
comments:
inline_comments:
0x80056604: "Loads FuncList1[3]"
0x8005660c: "Calls FuncList1[3] (i.e. something5)"
start_pos: 0x800565f4
@ -88,7 +88,7 @@
signature: fn()
desc: Setups interrupt and DMA.
If called again, simply returns.
comments:
inline_comments:
0x8005679c: Loads *something5_data1
0x800567a4: "If the loaded value is not zero, exit"
0x800567c0: Stop all interrupts by writing 0 to I_MASK
@ -111,7 +111,7 @@
- name: something6
signature: "fn(arg: u32)"
desc: ""
comments:
inline_comments:
0x80056404: Get the gpu status from `GPU_STAT`
0x80056408: Read the horizontal retrace from timer1
0x80056418: Read the horizontal retrace again.
@ -142,7 +142,7 @@
# ?
- name: something7
signature: "fn(a: u32, b: u32)"
comments:
inline_comments:
0x80056578: If something6_data1 >= a, return
0x8005659c: If (b << 15 - 1) != -1, goto try_again
0x800565dc: If something6_data1 < a, try again, else exit.
@ -174,7 +174,7 @@
- name: memset_zero
signature: "fn(u32* ptr, u32 size)"
desc: "Zeroes out the memory at `ptr` for `size` words.\n"
comments:
inline_comments:
0x80056c90: "If size == 0, return"
0x80056c94: size--
0x80056c9c: "*ptr = 0"
@ -199,29 +199,72 @@
start_pos: 0x8006a6b0
end_pos: 0x8006a6fc
- name: main_loop_sub1
- name: prng_next
signature: fn()
desc: "Called on loop by `main_loop` forever, maybe an interrupt breaks
out of the loop, but not sure how this function is related to that.\n
Simply reads from 0x801ddc10, calculates `(value * 0x41c64e6d) as u32 + 0x3039`,\n
storing it back into 0x801ddc10, then returns `value << 10 | 0x7fff`, where `value`
is the new value, just stored back."
desc: |-
Advances the current prng, stored at `cur_prng_value`.
Returns `cur_prng_value << 0x10 | 0x7fff`.
start_pos: 0x80069124
end_pos: 0x80069154
- name: something8
signature: "fn(a: u32, b: u32, c: u32, d: u32)"
desc: ""
comments:
inline_comments:
0x80061910: "args: ($s1, $s0, c & 0xffff, d & 0xffff)"
start_pos: 0x800618e4
end_pos: 0x80061954
- name: modify_spu_delay1
signature: "fn() -> u32"
desc: |-
Sets `SPU_DELAY` to `(SPU_DELAY & 0xf0fffff) | 0x2000ffff`
and returns the new value
inline_comments:
0x8004b45c: "$v0 = *SPU_DELAY"
0x8004b474: "*SPU_DELAY = $v0"
start_pos: 0x8004b428
end_pos: 0x8004b450
- name: modify_spu_delay2
signature: "fn() -> u32"
desc: |-
Sets `SPU_DELAY` to `(SPU_DELAY & 0xf0fffff) | 0x2200ffff`
and returns the new value
inline_comments:
0x8004b45c: "$v0 = *SPU_DELAY"
0x8004b474: "*SPU_DELAY = $v0"
start_pos: 0x8004b450
end_pos: 0x8004b478
- name: calc_0x890e6fbd
signature: "fn() -> u32"
desc: |-
Simply calculates and returns `0x890e6fbd`.
inline_comments:
0x8004b480: "$sp[0x4] = 0xd;"
0x8004b488: "$sp[0x4] = 0x0;"
0x8004b4a4: "$sp[0x4] *= 13;"
0x8004b4b4: "$sp[0x0] += 1;"
0x8004b4c4: "if $sp[0x0] <= 0x3c { goto .loop; }"
comments:
0x8004b48c: |-
let value = 0xd;
for _ in 0..0x3c {
value *= 13;
}
return value;
labels:
0x8004b48c: "loop"
0x8004b4b8: "while_condition"
start_pos: 0x8004b478
end_pos: 0x8004b4d4
# A functions
- name: InitHeap
signature: "fn(addr: *u32, size: u32)"
desc: Calls A(0x39)
comments:
inline_comments:
0x8006a738: Register tailcall. Likely to prevent calling in KSEG0 and do it in KUSEG
0x8006a73c: "arg: 0x39"
start_pos: 0x8006a734
@ -405,3 +448,297 @@
desc: Calls C(0x0a)
start_pos: 0x8006a894
end_pos: 0x8006a8a0
# Std
- name: sprintf
signature: "fn sprintf(buffer: *char, format: *const char, ...) -> i32"
inline_comments:
0x80069d6c: "if *buffer == '\\0' { goto.65; }"
0x80069d84: "if *buffer == '%' { goto .58; }"
comments:
0x80069d24: "Save arguments on wasted space."
0x80069d30: |-
Reserve stack space and save all additional
registers there
labels:
0x80069d84: "0"
0x80069db4: "1"
0x80069de8: "2"
0x80069e04: "3"
0x80069e14: "4"
0x80069e30: "5"
0x80069e4c: "6"
0x80069e84: "7"
0x80069e98: "8"
0x80069ed4: "9"
0x80069ee0: "10"
0x80069f34: "11"
0x80069f70: "12"
0x80069f7c: "13"
0x80069f9c: "14"
0x80069fbc: "15"
0x80069fc0: "16"
0x80069fe4: "17"
0x80069ff0: "18"
0x80069FFC: "66"
0x8006a008: "19"
0x8006a028: "20"
0x8006a058: "21"
0x8006a06c: "22"
0x8006a080: "23"
0x8006a0b0: "24"
0x8006a0b4: "25"
0x8006a0f4: "26"
0x8006a108: "27"
0x8006a118: "28"
0x8006a14c: "29"
0x8006a164: "30"
0x8006a180: "31"
0x8006a1a0: "32"
0x8006a1d0: "33"
0x8006a1f4: "34"
0x8006a208: "35"
0x8006a210: "36"
0x8006a22c: "37"
0x8006a268: "38"
0x8006a280: "39"
0x8006a2a0: "40"
0x8006a2b4: "41"
0x8006a2c0: "42"
0x8006a2c8: "43"
0x8006a2f8: "44"
0x8006a328: "45"
0x8006a33c: "46"
0x8006a344: "47"
0x8006a364: "48"
0x8006a380: "49"
0x8006a39c: "50"
0x8006a3cc: "51"
0x8006a3ec: "52"
0x8006a43c: "53"
0x8006a458: "54"
0x8006a478: "55"
0x8006a4a4: "56"
0x8006a4ac: "57"
0x8006a4b8: "58"
0x8006a4c4: "59"
0x8006a4ec: "60"
0x8006a514: "61"
0x8006a518: "62"
0x8006a534: "63"
0x8006a550: "64"
0x8006a570: "65"
start_pos: 0x80069d24
end_pos: 0x8006a5a4
- name: memcpy_args_reversed
signature: "fn(src: *const u8, dst: *mut u8, len: u32) -> *mut u8"
desc: |-
`memcpy` with the first two arguments swapped.
inline_comments:
0x80069044: "if src == NULL { return 0; }"
0x80069048: ""
0x8006904c: "if len <= 0 { return src; }"
comments:
0x80069054: |-
do {
*dst = *src;
src += 1;
len -= 1;
dst += 1;
} while (len > 0)
labels:
0x80069054: "loop"
0x8006906c: "end"
0x80069070: "on_null"
start_pos: 0x80069044
end_pos: 0x80069078
- name: mem_zero
signature: "fn(dst: *mut u8, len: u32) -> *mut u8"
desc: |-
Zeroes out `len` bytes of `dst`.
If `len <= 0`, returns `NULL`.
Otherwise returns `dst`.
inline_comments:
0x80069084: "if dst == NULL { return 0; }"
0x80069088: ""
0x8006908c: ""
0x80069090: "if len > 0 { _ret = dst; }"
0x80069094: "if len <= 0 { return 0; }"
comments:
0x8006909c: |-
do {
*dst = 0;
len -= 1;
dst += 1;
} while (len > 0)
labels:
0x8006909c: "loop"
0x800690ac: "end"
start_pos: 0x80069084
end_pos: 0x800690b4
- name: memcpy
signature: "fn(dst: *mut u8, src: *const u8, len: u32) -> *mut u8"
inline_comments:
0x800690b4: "if ptr == NULL { return 0; }"
0x800690b8: ""
0x800690bc: "if len <= 0 { return 0; }"
comments:
0x800690c4: |-
do {
*dst = *src;
src += 1;
len -= 1;
dst += 1;
} while (len > 0)
labels:
0x800690c4: "loop"
0x800690dc: "end"
0x800690e0: "on_null"
start_pos: 0x800690b4
end_pos: 0x800690e8
- name: memset
signature: "fn(dst: *mut u8, value: u32, len: u32) -> *mut u8"
inline_comments:
0x800690f4: "if ptr == NULL { return 0; }"
0x800690f8: ""
0x800690fc: ""
0x80069100: "if len > 0 { _ret = ptr; }"
0x80069104: "if len <= 0 { return 0; }"
comments:
0x8006910c: |-
do {
*dst = value;
len -= 1;
ptr += 1;
} while (len > 0)
labels:
0x8006910c: "loop"
0x8006911c: "end"
start_pos: 0x800690f4
end_pos: 0x80069124
- name: strcat
signature: "fn(dst: *mut u8, src: *const u8) -> *mut u8"
desc: ""
inline_comments:
0x8006917c: "if dst == NULL { return NULL; }"
0x80069180: ""
0x80069184: "if src == NULL { return NULL; }"
0x8006918c: "let dst_len = strlen(dst);"
0x80069190: ""
0x80069194: ""
0x80069198: "let src_len = strlen(src);"
0x800691a4: "if dst + dst_len == src + src_len { return NULL; }"
0x800691b4: "dst += 1; if *dst == 0 { goto go_back_1_dst; }"
0x800691cc: "dst -= 1;"
0x800691e8: "return dst;"
comments:
0x800691ac: |-
Skips `dst` until it hits one-past '\\0'.
Then backs up one and begins appending `src`
0x800691bc: |-
// Note: This causes `dst` to be one-past the null.
do {
let tmp = *dst;
dst += 1;
} while tmp != 0
0x800691d0: |-
// Note: The null is copied in this loop too.
do {
let tmp = *src;
*dst = src;
src += 1;
dst += 1;
} while tmp != 0
labels:
0x800691bc: "advance_dst_until_past_null"
0x800691cc: "go_back_1_dst"
0x800691d0: "loop"
0x800691ec: "on_null"
0x800691f0: "exit"
start_pos: 0x80069164
end_pos: 0x80069208
- name: strlen
signature: "fn(ptr: *const u8) -> u32"
desc: ""
inline_comments:
0x800692d8: "if ptr == NULL { return 0; }"
labels:
0x800692e8: "increase_len"
0x800692ec: "loop"
0x80069300: "on_null"
start_pos: 0x800692d4
end_pos: 0x80069308
# TODO: Investigate this more, seems weird
- name: strcmp
signature: "fn(lhs: *const u8, rhs: *const u8) -> u32"
desc: ""
inline_comments:
0x80069214: "if lhs == NULL { goto .lhs_null; }"
0x8006921c: "if rhs != NULL { goto .start_cmp; }"
0x80069224: "if lhs == rhs { return 0; } // Same as `rhs == NULL`"
0x80069228: ""
0x8006922c: "if lhs == NULL { return -1; } // Always true?"
0x80069234: "// Dead code?"
0x8006925c: "rhs += 1;"
0x80069248: "lhs += 1;"
0x8006926c: "return lhs[0] - rhs[-1]; // Note: This is because we don't advance `lhs` when we don't take the branch"
comments:
0x8006924c: |-
// Note: Includes the code from `.2` and `.1`
loop {
let left = *lhs;
let right = *rhs;
rhs += 1;
if left == right {
if *right == 0 { return 0; }
}
}
0x8006926c: |-
// This is because we update `rhs` prematurely in the previous loop.
// Note: This returns the lexicographic order by comparing the last character.
return lhs[0] - rhs[-1];
labels:
0x80069224: "lhs_null"
0x8006923c: "1"
0x80069244: "2"
0x8006924c: "start_cmp"
0x80069270: "exit"
start_pos: 0x80069214
end_pos: 0x80069278
- name: strcpy
signature: "fn(dst: *mut u8, src: *const u8) -> *mut u8"
desc: ""
inline_comments:
0x80069284: "if dst == NULL { return NULL; }"
0x80069288: ""
0x8006928c: "if dst == NULL { return NULL; }"
0x800692bc: "// Returns the original `lhs`"
comments:
0x80069294: |-
let tmp = *rhs;
rhs += 1;
*lhs = tmp;
lhs += 1;
if tmp == 0 { return lhs; }
0x800692a8: |-
do {
let tmp = *rhs;
rhs += 1;
*lhs = tmp;
lhs += 1;
if tmp == 0 { return lhs; }
}
labels:
0x800692a8: "loop"
0x800692bc: "end"
0x800692c0: "on_null"
start_pos: 0x80069284
end_pos: 0x800692c8