//! this is a distinct set of tests from the `yaxpeax-arm` root tests because i don't want extra
//! (optional!) dependencies in the disassembler's dependency tree.
use capstone::prelude::*;
use yaxpeax_arch::{Arch, Decoder};
#[test]
fn capstone_differential() {
let cs = Capstone::new()
.arm64()
.mode(capstone::arch::arm64::ArchMode::Arm)
.build()
.expect("can create capstone");
let yax = <yaxpeax_arm::armv8::a64::ARMv8 as Arch>::Decoder::default();
let mut mismatch = 0;
let mut good = 0;
let mut yax_reject = 0;
let mut missed_incomplete = 0;
for i in 0x00_00_00_00..u32::MAX {
let bytes = &i.to_le_bytes();
if i % 0x00_10_00_00 == 0 {
eprintln!("case {:08x}", i);
}
let res = cs.disasm_all(bytes, 0);
if let Ok(insts) = &res {
let insts_slice = insts.as_ref();
if insts_slice.len() == 1 {
// then yax should also succeed..
// and it should only be one instruction
let cs_text = format!("{}", insts_slice[0]);
let cs_text = &cs_text[5..];
let yax_res = yax.decode(&mut yaxpeax_arch::U8Reader::new(bytes));
let yax_text = if let Ok(inst) = yax_res {
format!("{}", inst)
} else if let Err(yaxpeax_arm::armv8::a64::DecodeError::IncompleteDecoder) = yax_res {
missed_incomplete += 1;
continue;
} else {
panic!("yax errored where capstone succeeded. cs text: '{}', bytes: {:x?}", cs_text, bytes);
};
fn acceptable_match(yax_text: &str, cs_text: &str) -> bool {
if yax_text == cs_text {
return true;
}
if cs_text
.replace("uxtw #0", "uxtw")
.replace("uxtx #0", "uxtx") == yax_text {
return true;
}
// capstone discards uxtw in some circumstances for reasons i don't yet
// know
if yax_text.ends_with("uxtw") &&
&yax_text[..yax_text.len() - 6] == cs_text {
return true;
}
if cs_text.ends_with("uxtw") &&
&cs_text[..cs_text.len() - 6] == yax_text {
return true;
}
if yax_text.replace("lsl", "uxtw") == cs_text {
return true;
}
if yax_text.ends_with("#0") &&
&yax_text[..yax_text.len() - 3] == cs_text {
return true;
}
if cs_text.ends_with("#0") &&
&cs_text[..cs_text.len() - 3] == yax_text {
return true;
}
if cs_text.starts_with(yax_text) && cs_text.ends_with("000") {
return true;
};
if cs_text.starts_with("ubfx ") {
return true;
}
if yax_text.starts_with("adrp ") {
return true;
}
if yax_text.starts_with("adr ") {
return true;
}
if yax_text.starts_with("b ") {
return true;
}
if yax_text.starts_with("bl ") {
return true;
}
// some instructions like `11400000` have an immeidate lsl #12 as their
// last operand. yax normalizes this to an unshifted `imm << 12`, capstone
// just prints lsl #12.
if cs_text.starts_with(yax_text) && cs_text.ends_with(", lsl #12") {
return true;
}
// yax and capstone deal with immediates in `mov reg, imm` a little
// differently. they're correct, but displayed differently (0xffffffff
// instead of -1)
if cs_text.starts_with("mov ") && yax_text.starts_with("mov ") {
return true;
}
// capstone just shows empty string for unrecognized prf{,u}m immediates,
// leaving broken text
if cs_text.starts_with("prfum ") && yax_text.starts_with("prfum ") {
return true;
}
if cs_text.starts_with("prfm ") && yax_text.starts_with("prfm ") {
return true;
}
// don't totally understand aliasing rules for `ORR (immediate)` and mov..
if cs_text.starts_with("mov ") && yax_text.starts_with("orr ") ||
cs_text.starts_with("orr ") && yax_text.starts_with("mov ")
{
return true;
}
// yax notmalizes movn to mov
if cs_text.starts_with("movn ") && yax_text.starts_with("mov ") {
return true;
}
// yax notmalizes movz to mov
if cs_text.starts_with("movz ") && yax_text.starts_with("mov ") {
return true;
}
// differences on displaying immediates..
let new_cs_text = cs_text
.replace("#0x", "")
.replace("#-0x", "")
.replace("#-", "")
.replace("#", "");
let new_yax_text = yax_text
.replace("#0x", "")
.replace("#-0x", "")
.replace("#-", "")
.replace("#", "")
.replace("$+0x", "");
if new_cs_text == new_yax_text {
return true;
}
if cs_text.len() > 7 && yax_text.len() > 7 {
if &cs_text[..7] == &yax_text[..7] && (cs_text.contains("#-") || yax_text.contains("#-")) {
return true;
}
if &cs_text[..7] == &yax_text[..7] && (cs_text.contains("shll") || yax_text.contains("shll")) {
return true;
}
}
// capstone doesn't show relative offsets, always makes absolute for some
// ip
if yax_text.contains("$-0x") || yax_text.contains("$+0x") {
return true;
}
if yax_text.contains("esb") {
return true;
}
if yax_text.contains("movi") {
return true;
}
if cs_text.starts_with("dup") && yax_text.starts_with("mov ") && cs_text.replace("dup ", "mov ") == yax_text {
return true;
}
// capstone bug! e0030033 is `bfxil w0, wzr, #0, #1`, but capstone picks
// the bfc alias instead. skip these, generally.
if yax_text.starts_with("bfxil") && (cs_text.starts_with("bfc") || cs_text.starts_with("bfi")) {
return true;
}
if cs_text.len() > 10 && yax_text.len() > 10 {
// eh they're probably the same but yax has a signed hex and capstone has
// unsigned
if &cs_text[..10] == &yax_text[..10] && cs_text.contains("ffffffff") && yax_text.contains("#-0x") {
return true;
}
// yax, for reg + shifted-reg operands, does not omit shift amount
if &cs_text[..10] == &yax_text[..10] && yax_text.contains(" #0x0]") {
return true;
}
// postindex offsets are base 10 in capstone sometimes?
if yax_text.contains("], #0x") && cs_text.contains("], #") &&
&cs_text[..20] == &yax_text[..20] {
return true;
}
}
// yax omits `uxt{w,x}` for extended reg where extension matches the
// register size
if cs_text.starts_with(yax_text) && (cs_text.ends_with("uxtx") || cs_text.ends_with("uxtw")) {
return true;
}
if cs_text.starts_with(yax_text) && cs_text.ends_with("0") {
return true;
}
// S being present or not has no bearing on the shift amount, #0 either
// way.
// yax will not print shift because of its ineffectual nature.
if (cs_text.starts_with("strb") || cs_text.starts_with("ldrb") || cs_text.starts_with("ldrsb") || cs_text.starts_with("ldr b") || cs_text.starts_with("str b")) && cs_text.contains(" lsl #0]") {
return true;
}
if cs_text == yax_text.replace(" #0", "") {
return true;
}
// yax uses lsl instead of uxtx when the reg size is uxtx. same for
// uxtw/w-regs
if cs_text.replace("uxtx", "lsl") == yax_text ||
cs_text.replace("uxtw", "lsl") == yax_text {
return true;
}
// yax shows dcps{1,2} operand, capstone does not?
if yax_text.starts_with("dcps") {
return true;
}
if cs_text.starts_with("msr ") {
return true;
}
// yax does not handle aliases for msr instructions yet
if yax_text.starts_with("msr ") {
return true;
}
// some kinda bug to deal with hint value width
if cs_text.starts_with("hint ") {
return true;
}
if cs_text.starts_with("dsb ") {
return true;
}
if cs_text.starts_with("clrex ") {
return true;
}
if yax_text.starts_with("sys ") {
return true;
}
if cs_text.starts_with("yield ") {
return true;
}
if cs_text.starts_with("wfe ") {
return true;
}
if cs_text.starts_with("wfi ") {
return true;
}
if cs_text.starts_with("sev ") {
return true;
}
if cs_text.starts_with("mrs ") {
return true;
}
if cs_text.starts_with("sysl ") {
return true;
}
if yax_text.starts_with("hint ") {
return true;
}
if yax_text == &cs_text[..cs_text.len() - 1] && cs_text.ends_with(" ") {
return true;
}
return false;
}
if !acceptable_match(&yax_text, cs_text) {
panic!("disassembly mismatch: {} != {}. bytes: {:x?}", yax_text, cs_text, bytes);
} else {
good += 1;
}
} else {
// yax should also fail?
}
}
}
eprintln!("match: {}", good);
eprintln!("mismatch: {}", mismatch);
eprintln!("bad reject: {}", yax_reject);
eprintln!("incomplete: {}", missed_incomplete);
}