Start modeling CPU

Wrote a shallow skeleton of a CPU Core.
Finally made the disassembler a clap subcommand.
This commit is contained in:
Michel Heily 2019-06-25 02:10:09 +03:00
parent addea1efa0
commit 9330c53957
11 changed files with 851 additions and 474 deletions

142
Cargo.lock generated
View file

@ -1,12 +1,21 @@
# This file is automatically @generated by Cargo.
# It is not intended for manual editing.
[[package]]
name = "arm7tdmi"
version = "0.1.0"
name = "ansi_term"
version = "0.11.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"bit 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
"enum-primitive-derive 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
"num-traits 0.1.43 (registry+https://github.com/rust-lang/crates.io-index)",
"winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "atty"
version = "0.2.11"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"libc 0.2.58 (registry+https://github.com/rust-lang/crates.io-index)",
"termion 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)",
"winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
@ -19,11 +28,31 @@ name = "bit"
version = "0.1.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "bitflags"
version = "1.1.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "byteorder"
version = "1.3.2"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "clap"
version = "2.33.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
"atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)",
"bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
"strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)",
"textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)",
"unicode-width 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
"vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)",
"yaml-rust 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "enum-primitive-derive"
version = "0.1.2"
@ -34,6 +63,11 @@ dependencies = [
"syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "libc"
version = "0.2.58"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "num-traits"
version = "0.1.43"
@ -50,19 +84,45 @@ dependencies = [
"autocfg 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "numtoa"
version = "0.1.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "quote"
version = "0.3.15"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "redox_syscall"
version = "0.1.54"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "redox_termios"
version = "0.1.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"redox_syscall 0.1.54 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "rustboyadvance"
version = "0.1.0"
dependencies = [
"arm7tdmi 0.1.0",
"bit 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
"byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)",
"clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)",
"enum-primitive-derive 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)",
"num-traits 0.1.43 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "strsim"
version = "0.8.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "syn"
version = "0.11.11"
@ -81,19 +141,89 @@ dependencies = [
"unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "termion"
version = "1.5.3"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"libc 0.2.58 (registry+https://github.com/rust-lang/crates.io-index)",
"numtoa 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)",
"redox_syscall 0.1.54 (registry+https://github.com/rust-lang/crates.io-index)",
"redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "textwrap"
version = "0.11.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"unicode-width 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "unicode-width"
version = "0.1.5"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "unicode-xid"
version = "0.0.4"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "vec_map"
version = "0.8.1"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "winapi"
version = "0.3.7"
source = "registry+https://github.com/rust-lang/crates.io-index"
dependencies = [
"winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
"winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)",
]
[[package]]
name = "winapi-i686-pc-windows-gnu"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "winapi-x86_64-pc-windows-gnu"
version = "0.4.0"
source = "registry+https://github.com/rust-lang/crates.io-index"
[[package]]
name = "yaml-rust"
version = "0.3.5"
source = "registry+https://github.com/rust-lang/crates.io-index"
[metadata]
"checksum ansi_term 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ee49baf6cb617b853aa8d93bf420db2383fab46d314482ca2803b40d5fde979b"
"checksum atty 0.2.11 (registry+https://github.com/rust-lang/crates.io-index)" = "9a7d5b8723950951411ee34d271d99dddcc2035a16ab25310ea2c8cfd4369652"
"checksum autocfg 0.1.4 (registry+https://github.com/rust-lang/crates.io-index)" = "0e49efa51329a5fd37e7c79db4621af617cd4e3e5bc224939808d076077077bf"
"checksum bit 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "2b645c5c09a7d4035949cfce1a915785aaad6f17800c35fda8a8c311c491f284"
"checksum bitflags 1.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "3d155346769a6855b86399e9bc3814ab343cd3d62c7e985113d46a0ec3c281fd"
"checksum byteorder 1.3.2 (registry+https://github.com/rust-lang/crates.io-index)" = "a7c3dd8985a7111efc5c80b44e23ecdd8c007de8ade3b96595387e812b957cf5"
"checksum clap 2.33.0 (registry+https://github.com/rust-lang/crates.io-index)" = "5067f5bb2d80ef5d68b4c87db81601f0b75bca627bc2ef76b141d7b846a3c6d9"
"checksum enum-primitive-derive 0.1.2 (registry+https://github.com/rust-lang/crates.io-index)" = "e2b90e520ec62c1864c8c78d637acbfe8baf5f63240f2fb8165b8325c07812dd"
"checksum libc 0.2.58 (registry+https://github.com/rust-lang/crates.io-index)" = "6281b86796ba5e4366000be6e9e18bf35580adf9e63fbe2294aadb587613a319"
"checksum num-traits 0.1.43 (registry+https://github.com/rust-lang/crates.io-index)" = "92e5113e9fd4cc14ded8e499429f396a20f98c772a47cc8622a736e1ec843c31"
"checksum num-traits 0.2.8 (registry+https://github.com/rust-lang/crates.io-index)" = "6ba9a427cfca2be13aa6f6403b0b7e7368fe982bfa16fccc450ce74c46cd9b32"
"checksum numtoa 0.1.0 (registry+https://github.com/rust-lang/crates.io-index)" = "b8f8bdf33df195859076e54ab11ee78a1b208382d3a26ec40d142ffc1ecc49ef"
"checksum quote 0.3.15 (registry+https://github.com/rust-lang/crates.io-index)" = "7a6e920b65c65f10b2ae65c831a81a073a89edd28c7cce89475bff467ab4167a"
"checksum redox_syscall 0.1.54 (registry+https://github.com/rust-lang/crates.io-index)" = "12229c14a0f65c4f1cb046a3b52047cdd9da1f4b30f8a39c5063c8bae515e252"
"checksum redox_termios 0.1.1 (registry+https://github.com/rust-lang/crates.io-index)" = "7e891cfe48e9100a70a3b6eb652fef28920c117d366339687bd5576160db0f76"
"checksum strsim 0.8.0 (registry+https://github.com/rust-lang/crates.io-index)" = "8ea5119cdb4c55b55d432abb513a0429384878c15dde60cc77b1c99de1a95a6a"
"checksum syn 0.11.11 (registry+https://github.com/rust-lang/crates.io-index)" = "d3b891b9015c88c576343b9b3e41c2c11a51c219ef067b264bd9c8aa9b441dad"
"checksum synom 0.11.3 (registry+https://github.com/rust-lang/crates.io-index)" = "a393066ed9010ebaed60b9eafa373d4b1baac186dd7e008555b0f702b51945b6"
"checksum termion 1.5.3 (registry+https://github.com/rust-lang/crates.io-index)" = "6a8fb22f7cde82c8220e5aeacb3258ed7ce996142c77cba193f203515e26c330"
"checksum textwrap 0.11.0 (registry+https://github.com/rust-lang/crates.io-index)" = "d326610f408c7a4eb6f51c37c330e496b08506c9457c9d34287ecc38809fb060"
"checksum unicode-width 0.1.5 (registry+https://github.com/rust-lang/crates.io-index)" = "882386231c45df4700b275c7ff55b6f3698780a650026380e72dabe76fa46526"
"checksum unicode-xid 0.0.4 (registry+https://github.com/rust-lang/crates.io-index)" = "8c1f860d7d29cf02cb2f3f359fd35991af3d30bac52c57d265a3c461074cb4dc"
"checksum vec_map 0.8.1 (registry+https://github.com/rust-lang/crates.io-index)" = "05c78687fb1a80548ae3250346c3db86a80a7cdd77bda190189f2d0a0987c81a"
"checksum winapi 0.3.7 (registry+https://github.com/rust-lang/crates.io-index)" = "f10e386af2b13e47c89e7236a7a14a086791a2b88ebad6df9bf42040195cf770"
"checksum winapi-i686-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "ac3b87c63620426dd9b991e5ce0329eff545bccbbb34f3be09ff6fb6ab51b7b6"
"checksum winapi-x86_64-pc-windows-gnu 0.4.0 (registry+https://github.com/rust-lang/crates.io-index)" = "712e227841d057c1ee1cd2fb22fa7e5a5461ae8e48fa2ca79ec42cfc1931183f"
"checksum yaml-rust 0.3.5 (registry+https://github.com/rust-lang/crates.io-index)" = "e66366e18dc58b46801afbf2ca7661a9f59cc8c5962c29892b6039b4f86fa992"

View file

@ -9,8 +9,4 @@ byteorder = "*"
enum-primitive-derive = "^0.1"
num-traits = "^0.1"
bit = "^0.1"
clap = {version = "2.33", features = ["color", "yaml"]}
[[bin]]
name = "disass"
path = "src/disass.rs"
clap = {version = "2.33", features = ["color", "yaml"]}

View file

@ -1,373 +0,0 @@
use crate::bit::BitIndex;
use crate::num_traits::FromPrimitive;
use std::convert::TryFrom;
pub use super::display;
#[derive(Debug, PartialEq)]
pub enum ArmError {
UnknownInstructionFormat(u32),
UndefinedConditionCode(u32),
InvalidShiftType(u32),
InvalidHSBits(u32),
}
#[derive(Debug, Copy, Clone, PartialEq, Primitive)]
pub enum ArmCond {
Equal = 0b0000,
NotEqual = 0b0001,
UnsignedHigherOrSame = 0b0010,
UnsignedLower = 0b0011,
Negative = 0b0100,
PositiveOrZero = 0b0101,
Overflow = 0b0110,
NoOverflow = 0b0111,
UnsignedHigher = 0b1000,
UnsignedLowerOrSame = 0b1001,
GreaterOrEqual = 0b1010,
LessThan = 0b1011,
GreaterThan = 0b1100,
LessThanOrEqual = 0b1101,
Always = 0b1110,
}
#[derive(Debug, Copy, Clone, PartialEq)]
#[allow(non_camel_case_types)]
pub enum ArmInstructionFormat {
// Branch and Exchange
BX,
// Branch /w Link
B_BL,
// Multiply and Multiply-Accumulate
MUL_MLA,
// Multiply Long and Multiply-Accumulate Long
MULL_MLAL,
// Single Data Transfer
LDR_STR,
// Halfword and Signed Data Transfer
LDR_STR_HS_REG,
// Halfword and Signed Data Transfer
LDR_STR_HS_IMM,
// Data Processing
DP,
// Block Data Transfer
LDM_STM,
// Single Data Swap
SWP,
// Transfer PSR contents to a register
MRS,
// Transfer register contents to PSR
MSR_REG,
// Tanssfer immediate/register to PSR flags only
MSR_FLAGS,
}
#[derive(Debug, Primitive)]
pub enum ArmOpCode {
AND = 0b0000,
EOR = 0b0001,
SUB = 0b0010,
RSB = 0b0011,
ADD = 0b0100,
ADC = 0b0101,
SBC = 0b0110,
RSC = 0b0111,
TST = 0b1000,
TEQ = 0b1001,
CMP = 0b1010,
CMN = 0b1011,
ORR = 0b1100,
MOV = 0b1101,
BIC = 0b1110,
MVN = 0b1111,
}
#[derive(Debug, PartialEq, Primitive)]
pub enum ArmHalfwordTransferType {
UnsignedHalfwords = 0b01,
SignedByte = 0b10,
SignedHalfwords = 0b11,
}
#[derive(Debug, Copy, Clone, PartialEq)]
pub struct ArmInstruction {
pub cond: ArmCond,
pub fmt: ArmInstructionFormat,
pub raw: u32,
pub pc: u32,
}
impl TryFrom<(u32, u32)> for ArmInstruction {
type Error = ArmError;
fn try_from(value: (u32, u32)) -> Result<Self, Self::Error> {
use ArmInstructionFormat::*;
let (raw, addr) = value;
let cond_code = raw.bit_range(28..32) as u8;
let cond = match ArmCond::from_u8(cond_code) {
Some(cond) => Ok(cond),
None => Err(ArmError::UndefinedConditionCode(cond_code as u32)),
}?;
let fmt = if (0x0fff_fff0 & raw) == 0x012f_ff10 {
Ok(BX)
} else if (0x0e00_0000 & raw) == 0x0a00_0000 {
Ok(B_BL)
} else if (0xe000_0010 & raw) == 0x0600_0000 {
Err(ArmError::UnknownInstructionFormat(raw))
} else if (0x0fb0_0ff0 & raw) == 0x0100_0090 {
Ok(SWP)
} else if (0x0fc0_00f0 & raw) == 0x0000_0090 {
Ok(MUL_MLA)
} else if (0x0f80_00f0 & raw) == 0x0080_0090 {
Ok(MULL_MLAL)
} else if (0x0fbf_0fff & raw) == 0x010f_0000 {
Ok(MRS)
} else if (0x0fbf_fff0 & raw) == 0x0129_f000 {
Ok(MSR_REG)
} else if (0x0dbf_f000 & raw) == 0x0128_f000 {
Ok(MSR_FLAGS)
} else if (0x0c00_0000 & raw) == 0x0400_0000 {
Ok(LDR_STR)
} else if (0x0e40_0F90 & raw) == 0x0000_0090 {
Ok(LDR_STR_HS_REG)
} else if (0x0e40_0090 & raw) == 0x0040_0090 {
Ok(LDR_STR_HS_IMM)
} else if (0x0e00_0000 & raw) == 0x0800_0000 {
Ok(LDM_STM)
} else if (0x0c00_0000 & raw) == 0x0000_0000 {
Ok(DP)
} else {
Err(ArmError::UnknownInstructionFormat(raw))
}?;
Ok(ArmInstruction {
cond: cond,
fmt: fmt,
raw: raw,
pc: addr,
})
}
}
#[derive(Debug, PartialEq, Primitive)]
pub enum ArmShiftType {
LSL = 0,
LSR = 1,
ASR = 2,
ROR = 3,
}
#[derive(Debug, PartialEq)]
pub enum ArmShift {
ImmediateShift(u32, ArmShiftType),
RegisterShift(usize, ArmShiftType),
}
impl TryFrom<u32> for ArmShift {
type Error = ArmError;
fn try_from(v: u32) -> Result<Self, Self::Error> {
let typ = match ArmShiftType::from_u8(v.bit_range(5..7) as u8) {
Some(s) => Ok(s),
_ => Err(ArmError::InvalidShiftType(v.bit_range(5..7))),
}?;
if v.bit(4) {
let rs = v.bit_range(8..12) as usize;
Ok(ArmShift::RegisterShift(rs, typ))
} else {
let amount = v.bit_range(7..12) as u32;
Ok(ArmShift::ImmediateShift(amount, typ))
}
}
}
#[derive(Debug, PartialEq)]
pub enum ArmShiftedValue {
ImmediateValue(i32),
RotatedImmediate(u32, u32),
ShiftedRegister {
reg: usize,
shift: ArmShift,
added: Option<bool>,
},
}
impl ArmShiftedValue {
/// Decode operand2 as an immediate value
pub fn decode_rotated_immediate(&self) -> Option<i32> {
if let ArmShiftedValue::RotatedImmediate(immediate, rotate) = self {
return Some(immediate.rotate_right(*rotate) as i32);
}
None
}
}
impl ArmInstruction {
pub fn rn(&self) -> usize {
match self.fmt {
ArmInstructionFormat::MUL_MLA => self.raw.bit_range(12..16) as usize,
ArmInstructionFormat::MULL_MLAL => self.raw.bit_range(8..12) as usize,
ArmInstructionFormat::BX => self.raw.bit_range(0..4) as usize,
_ => self.raw.bit_range(16..20) as usize,
}
}
pub fn rd(&self) -> usize {
match self.fmt {
ArmInstructionFormat::MUL_MLA => self.raw.bit_range(16..20) as usize,
_ => self.raw.bit_range(12..16) as usize,
}
}
pub fn rm(&self) -> usize {
self.raw.bit_range(0..4) as usize
}
pub fn rs(&self) -> usize {
self.raw.bit_range(8..12) as usize
}
pub fn rd_lo(&self) -> usize {
self.raw.bit_range(12..16) as usize
}
pub fn rd_hi(&self) -> usize {
self.raw.bit_range(16..20) as usize
}
pub fn opcode(&self) -> Option<ArmOpCode> {
ArmOpCode::from_u32(self.raw.bit_range(21..25))
}
pub fn branch_offset(&self) -> i32 {
((((self.raw << 8) as i32) >> 8) << 2) + 8
}
pub fn load_flag(&self) -> bool {
self.raw.bit(20)
}
pub fn set_cond_flag(&self) -> bool {
self.raw.bit(20)
}
pub fn write_back_flag(&self) -> bool {
self.raw.bit(21)
}
pub fn accumulate_flag(&self) -> bool {
self.raw.bit(21)
}
pub fn u_flag(&self) -> bool {
self.raw.bit(22)
}
pub fn halfword_data_transfer_type(&self) -> Result<ArmHalfwordTransferType, ArmError> {
match ArmHalfwordTransferType::from_u32((self.raw & 0b1100000) >> 5) {
Some(x) => Ok(x),
None => Err(ArmError::InvalidHSBits(self.raw)),
}
}
pub fn transfer_size(&self) -> usize {
if self.raw.bit(22) {
1
} else {
4
}
}
pub fn is_loading_psr_and_forcing_user_mode(&self) -> bool {
self.raw.bit(22)
}
pub fn spsr_flag(&self) -> bool {
self.raw.bit(22)
}
pub fn add_offset_flag(&self) -> bool {
self.raw.bit(23)
}
pub fn pre_index_flag(&self) -> bool {
self.raw.bit(24)
}
pub fn link_flag(&self) -> bool {
self.raw.bit(24)
}
/// gets offset used by ldr/str instructions
pub fn ldr_str_offset(&self) -> ArmShiftedValue {
let ofs = self.raw.bit_range(0..12);
if self.raw.bit(25) {
let rm = ofs & 0xf;
let shift = ArmShift::try_from(ofs).unwrap();
ArmShiftedValue::ShiftedRegister {
reg: rm as usize,
shift: shift,
added: Some(self.add_offset_flag()),
}
} else {
let ofs = if self.add_offset_flag() {
ofs as i32
} else {
-(ofs as i32)
};
ArmShiftedValue::ImmediateValue(ofs)
}
}
pub fn ldr_str_hs_offset(&self) -> Option<ArmShiftedValue> {
match self.fmt {
ArmInstructionFormat::LDR_STR_HS_IMM => {
let offset8 = (self.raw.bit_range(8..12) << 4) + self.raw.bit_range(0..4);
let offset8 = if self.add_offset_flag() {
offset8 as i32
} else {
-(offset8 as i32)
};
Some(ArmShiftedValue::ImmediateValue(offset8))
},
ArmInstructionFormat::LDR_STR_HS_REG => {
Some(ArmShiftedValue::ShiftedRegister {
reg: (self.raw & 0xf) as usize,
shift: ArmShift::ImmediateShift(0, ArmShiftType::LSL),
added: Some(self.add_offset_flag())
})
},
_ => None
}
}
pub fn operand2(&self) -> ArmShiftedValue {
let op2 = self.raw.bit_range(0..12);
if self.raw.bit(25) {
let immediate = op2 & 0xff;
let rotate = 2 * op2.bit_range(8..12);
ArmShiftedValue::RotatedImmediate(immediate, rotate)
} else {
let reg = op2 & 0xf;
let shift = ArmShift::try_from(op2).unwrap(); // TODO error handling
ArmShiftedValue::ShiftedRegister {
reg: reg as usize,
shift: shift,
added: None,
}
}
}
pub fn register_list(&self) -> Vec<usize> {
let list_bits = self.raw & 0xffff;
let mut list = Vec::with_capacity(16);
for i in 0..16 {
if (list_bits & (1 << i)) != 0 {
list.push(i)
}
}
list
}
}

View file

@ -1,7 +1,7 @@
use super::super::{reg_string, REG_PC};
use super::arm_isa::{
ArmCond, ArmInstruction, ArmInstructionFormat, ArmShiftedValue, ArmOpCode, ArmShift,
ArmShiftType, ArmHalfwordTransferType
use super::{
ArmCond, ArmHalfwordTransferType, ArmInstruction, ArmInstructionFormat, ArmOpCode, ArmShift,
ArmShiftType, ArmShiftedValue,
};
use std::fmt;
@ -108,9 +108,13 @@ impl ArmInstruction {
ofs = self.pc.wrapping_add(self.branch_offset() as u32) as u32
)
}
fn set_cond_mark(&self) -> &str {
if self.set_cond_flag() { "s" } else { "" }
if self.set_cond_flag() {
"s"
} else {
""
}
}
fn fmt_data_processing(&self, f: &mut fmt::Formatter) -> fmt::Result {
@ -145,21 +149,27 @@ impl ArmInstruction {
),
}?;
let operand2 = self.operand2();
let operand2 = self.operand2().unwrap();
match operand2 {
ArmShiftedValue::RotatedImmediate(_, _) => {
let value = operand2.decode_rotated_immediate().unwrap();
write!(f, "#{}\t; {:#x}", value, value)
}
ArmShiftedValue::ShiftedRegister{reg, shift, added: _} => {
write!(f, "{}", self.make_shifted_reg_string(reg, shift))
}
ArmShiftedValue::ShiftedRegister {
reg,
shift,
added: _,
} => write!(f, "{}", self.make_shifted_reg_string(reg, shift)),
_ => write!(f, "RegisterNotImpl"),
}
}
fn auto_incremenet_mark(&self) -> &str {
if self.write_back_flag() { "!" } else { "" }
if self.write_back_flag() {
"!"
} else {
""
}
}
fn fmt_rn_offset(&self, f: &mut fmt::Formatter, offset: ArmShiftedValue) -> fmt::Result {
@ -176,8 +186,16 @@ impl ArmInstruction {
Some(format!("\t; {:#x}", value_for_commnet)),
)
}
ArmShiftedValue::ShiftedRegister{reg, shift, added: Some(added)} => (
format!("{}{}", if added { "" } else { "-" }, self.make_shifted_reg_string(reg, shift)),
ArmShiftedValue::ShiftedRegister {
reg,
shift,
added: Some(added),
} => (
format!(
"{}{}",
if added { "" } else { "-" },
self.make_shifted_reg_string(reg, shift)
),
None,
),
_ => panic!("bad barrel shifter"),
@ -211,7 +229,7 @@ impl ArmInstruction {
Rd = reg_string(self.rd()),
)?;
self.fmt_rn_offset(f, self.ldr_str_offset())
self.fmt_rn_offset(f, self.ldr_str_offset().unwrap())
}
fn fmt_ldm_stm(&self, f: &mut fmt::Formatter) -> fmt::Result {
@ -284,7 +302,11 @@ impl ArmInstruction {
}
fn sign_mark(&self) -> &str {
if self.u_flag() { "s" } else { "u" }
if self.u_flag() {
"s"
} else {
"u"
}
}
fn fmt_mull_mlal(&self, f: &mut fmt::Formatter) -> fmt::Result {
@ -314,7 +336,7 @@ impl ArmInstruction {
}
}
fn fmt_ldr_str_hs(&self, f: &mut fmt::Formatter) -> fmt::Result{
fn fmt_ldr_str_hs(&self, f: &mut fmt::Formatter) -> fmt::Result {
if let Ok(transfer_type) = self.halfword_data_transfer_type() {
write!(
f,

View file

@ -1,2 +1,403 @@
pub mod arm_isa;
pub mod display;
use crate::bit::BitIndex;
use crate::num_traits::FromPrimitive;
use std::convert::TryFrom;
#[derive(Debug, PartialEq)]
pub enum ArmDecodeErrorKind {
UnknownInstructionFormat,
DecodedPartDoesNotBelongToInstruction,
UndefinedConditionCode(u32),
InvalidShiftType(u32),
InvalidHSBits(u32),
}
use ArmDecodeErrorKind::*;
#[derive(Debug, PartialEq)]
pub struct ArmDecodeError {
pub kind: ArmDecodeErrorKind,
pub insn: u32,
pub addr: u32,
}
impl ArmDecodeError {
fn new(kind: ArmDecodeErrorKind, insn: u32, addr: u32) -> ArmDecodeError {
ArmDecodeError {
kind: kind,
insn: insn,
addr: addr,
}
}
}
#[derive(Debug, Copy, Clone, PartialEq, Primitive)]
pub enum ArmCond {
Equal = 0b0000,
NotEqual = 0b0001,
UnsignedHigherOrSame = 0b0010,
UnsignedLower = 0b0011,
Negative = 0b0100,
PositiveOrZero = 0b0101,
Overflow = 0b0110,
NoOverflow = 0b0111,
UnsignedHigher = 0b1000,
UnsignedLowerOrSame = 0b1001,
GreaterOrEqual = 0b1010,
LessThan = 0b1011,
GreaterThan = 0b1100,
LessThanOrEqual = 0b1101,
Always = 0b1110,
}
#[derive(Debug, Copy, Clone, PartialEq)]
#[allow(non_camel_case_types)]
pub enum ArmInstructionFormat {
// Branch and Exchange
BX,
// Branch /w Link
B_BL,
// Multiply and Multiply-Accumulate
MUL_MLA,
// Multiply Long and Multiply-Accumulate Long
MULL_MLAL,
// Single Data Transfer
LDR_STR,
// Halfword and Signed Data Transfer
LDR_STR_HS_REG,
// Halfword and Signed Data Transfer
LDR_STR_HS_IMM,
// Data Processing
DP,
// Block Data Transfer
LDM_STM,
// Single Data Swap
SWP,
// Transfer PSR contents to a register
MRS,
// Transfer register contents to PSR
MSR_REG,
// Tanssfer immediate/register to PSR flags only
MSR_FLAGS,
}
#[derive(Debug, Primitive)]
pub enum ArmOpCode {
AND = 0b0000,
EOR = 0b0001,
SUB = 0b0010,
RSB = 0b0011,
ADD = 0b0100,
ADC = 0b0101,
SBC = 0b0110,
RSC = 0b0111,
TST = 0b1000,
TEQ = 0b1001,
CMP = 0b1010,
CMN = 0b1011,
ORR = 0b1100,
MOV = 0b1101,
BIC = 0b1110,
MVN = 0b1111,
}
#[derive(Debug, PartialEq, Primitive)]
pub enum ArmHalfwordTransferType {
UnsignedHalfwords = 0b01,
SignedByte = 0b10,
SignedHalfwords = 0b11,
}
#[derive(Debug, Copy, Clone, PartialEq)]
pub struct ArmInstruction {
pub cond: ArmCond,
pub fmt: ArmInstructionFormat,
pub raw: u32,
pub pc: u32,
}
impl TryFrom<(u32, u32)> for ArmInstruction {
type Error = ArmDecodeError;
fn try_from(value: (u32, u32)) -> Result<Self, Self::Error> {
use ArmInstructionFormat::*;
let (raw, addr) = value;
let cond_code = raw.bit_range(28..32) as u8;
let cond = match ArmCond::from_u8(cond_code) {
Some(cond) => Ok(cond),
None => Err(ArmDecodeError::new(
UndefinedConditionCode(cond_code as u32),
raw,
addr,
)),
}?;
let fmt = if (0x0fff_fff0 & raw) == 0x012f_ff10 {
Ok(BX)
} else if (0x0e00_0000 & raw) == 0x0a00_0000 {
Ok(B_BL)
} else if (0xe000_0010 & raw) == 0x0600_0000 {
Err(ArmDecodeError::new(UnknownInstructionFormat, raw, addr))
} else if (0x0fb0_0ff0 & raw) == 0x0100_0090 {
Ok(SWP)
} else if (0x0fc0_00f0 & raw) == 0x0000_0090 {
Ok(MUL_MLA)
} else if (0x0f80_00f0 & raw) == 0x0080_0090 {
Ok(MULL_MLAL)
} else if (0x0fbf_0fff & raw) == 0x010f_0000 {
Ok(MRS)
} else if (0x0fbf_fff0 & raw) == 0x0129_f000 {
Ok(MSR_REG)
} else if (0x0dbf_f000 & raw) == 0x0128_f000 {
Ok(MSR_FLAGS)
} else if (0x0c00_0000 & raw) == 0x0400_0000 {
Ok(LDR_STR)
} else if (0x0e40_0F90 & raw) == 0x0000_0090 {
Ok(LDR_STR_HS_REG)
} else if (0x0e40_0090 & raw) == 0x0040_0090 {
Ok(LDR_STR_HS_IMM)
} else if (0x0e00_0000 & raw) == 0x0800_0000 {
Ok(LDM_STM)
} else if (0x0c00_0000 & raw) == 0x0000_0000 {
Ok(DP)
} else {
Err(ArmDecodeError::new(UnknownInstructionFormat, raw, addr))
}?;
Ok(ArmInstruction {
cond: cond,
fmt: fmt,
raw: raw,
pc: addr,
})
}
}
#[derive(Debug, PartialEq, Primitive)]
pub enum ArmShiftType {
LSL = 0,
LSR = 1,
ASR = 2,
ROR = 3,
}
#[derive(Debug, PartialEq)]
pub enum ArmShift {
ImmediateShift(u32, ArmShiftType),
RegisterShift(usize, ArmShiftType),
}
impl TryFrom<u32> for ArmShift {
type Error = ArmDecodeErrorKind;
fn try_from(v: u32) -> Result<Self, Self::Error> {
let typ = match ArmShiftType::from_u8(v.bit_range(5..7) as u8) {
Some(s) => Ok(s),
_ => Err(InvalidShiftType(v.bit_range(5..7))),
}?;
if v.bit(4) {
let rs = v.bit_range(8..12) as usize;
Ok(ArmShift::RegisterShift(rs, typ))
} else {
let amount = v.bit_range(7..12) as u32;
Ok(ArmShift::ImmediateShift(amount, typ))
}
}
}
#[derive(Debug, PartialEq)]
pub enum ArmShiftedValue {
ImmediateValue(i32),
RotatedImmediate(u32, u32),
ShiftedRegister {
reg: usize,
shift: ArmShift,
added: Option<bool>,
},
}
impl ArmShiftedValue {
/// Decode operand2 as an immediate value
pub fn decode_rotated_immediate(&self) -> Option<i32> {
if let ArmShiftedValue::RotatedImmediate(immediate, rotate) = self {
return Some(immediate.rotate_right(*rotate) as i32);
}
None
}
}
impl ArmInstruction {
fn make_decode_error(&self, kind: ArmDecodeErrorKind) -> ArmDecodeError {
ArmDecodeError {
kind: kind,
insn: self.raw,
addr: self.pc,
}
}
pub fn rn(&self) -> usize {
match self.fmt {
ArmInstructionFormat::MUL_MLA => self.raw.bit_range(12..16) as usize,
ArmInstructionFormat::MULL_MLAL => self.raw.bit_range(8..12) as usize,
ArmInstructionFormat::BX => self.raw.bit_range(0..4) as usize,
_ => self.raw.bit_range(16..20) as usize,
}
}
pub fn rd(&self) -> usize {
match self.fmt {
ArmInstructionFormat::MUL_MLA => self.raw.bit_range(16..20) as usize,
_ => self.raw.bit_range(12..16) as usize,
}
}
pub fn rm(&self) -> usize {
self.raw.bit_range(0..4) as usize
}
pub fn rs(&self) -> usize {
self.raw.bit_range(8..12) as usize
}
pub fn rd_lo(&self) -> usize {
self.raw.bit_range(12..16) as usize
}
pub fn rd_hi(&self) -> usize {
self.raw.bit_range(16..20) as usize
}
pub fn opcode(&self) -> Option<ArmOpCode> {
ArmOpCode::from_u32(self.raw.bit_range(21..25))
}
pub fn branch_offset(&self) -> i32 {
((((self.raw << 8) as i32) >> 8) << 2) + 8
}
pub fn load_flag(&self) -> bool {
self.raw.bit(20)
}
pub fn set_cond_flag(&self) -> bool {
self.raw.bit(20)
}
pub fn write_back_flag(&self) -> bool {
self.raw.bit(21)
}
pub fn accumulate_flag(&self) -> bool {
self.raw.bit(21)
}
pub fn u_flag(&self) -> bool {
self.raw.bit(22)
}
pub fn halfword_data_transfer_type(&self) -> Result<ArmHalfwordTransferType, ArmDecodeError> {
let bits = (self.raw & 0b1100000) >> 5;
match ArmHalfwordTransferType::from_u32(bits) {
Some(x) => Ok(x),
None => Err(ArmDecodeError::new(InvalidHSBits(bits), self.raw, self.pc)),
}
}
pub fn transfer_size(&self) -> usize {
if self.raw.bit(22) {
1
} else {
4
}
}
pub fn is_loading_psr_and_forcing_user_mode(&self) -> bool {
self.raw.bit(22)
}
pub fn spsr_flag(&self) -> bool {
self.raw.bit(22)
}
pub fn add_offset_flag(&self) -> bool {
self.raw.bit(23)
}
pub fn pre_index_flag(&self) -> bool {
self.raw.bit(24)
}
pub fn link_flag(&self) -> bool {
self.raw.bit(24)
}
/// gets offset used by ldr/str instructions
pub fn ldr_str_offset(&self) -> Result<ArmShiftedValue, ArmDecodeError> {
let ofs = self.raw.bit_range(0..12);
if self.raw.bit(25) {
let rm = ofs & 0xf;
let shift = ArmShift::try_from(ofs).map_err(|kind| self.make_decode_error(kind))?;
Ok(ArmShiftedValue::ShiftedRegister {
reg: rm as usize,
shift: shift,
added: Some(self.add_offset_flag()),
})
} else {
let ofs = if self.add_offset_flag() {
ofs as i32
} else {
-(ofs as i32)
};
Ok(ArmShiftedValue::ImmediateValue(ofs))
}
}
pub fn ldr_str_hs_offset(&self) -> Result<ArmShiftedValue, ArmDecodeError> {
match self.fmt {
ArmInstructionFormat::LDR_STR_HS_IMM => {
let offset8 = (self.raw.bit_range(8..12) << 4) + self.raw.bit_range(0..4);
let offset8 = if self.add_offset_flag() {
offset8 as i32
} else {
-(offset8 as i32)
};
Ok(ArmShiftedValue::ImmediateValue(offset8))
}
ArmInstructionFormat::LDR_STR_HS_REG => Ok(ArmShiftedValue::ShiftedRegister {
reg: (self.raw & 0xf) as usize,
shift: ArmShift::ImmediateShift(0, ArmShiftType::LSL),
added: Some(self.add_offset_flag()),
}),
_ => Err(self.make_decode_error(DecodedPartDoesNotBelongToInstruction)),
}
}
pub fn operand2(&self) -> Result<ArmShiftedValue, ArmDecodeError> {
let op2 = self.raw.bit_range(0..12);
if self.raw.bit(25) {
let immediate = op2 & 0xff;
let rotate = 2 * op2.bit_range(8..12);
Ok(ArmShiftedValue::RotatedImmediate(immediate, rotate))
} else {
let reg = op2 & 0xf;
let shift = ArmShift::try_from(op2).map_err(|kind| self.make_decode_error(kind))?; // TODO error handling
Ok(ArmShiftedValue::ShiftedRegister {
reg: reg as usize,
shift: shift,
added: None,
})
}
}
pub fn register_list(&self) -> Vec<usize> {
let list_bits = self.raw & 0xffff;
let mut list = Vec::with_capacity(16);
for i in 0..16 {
if (list_bits & (1 << i)) != 0 {
list.push(i)
}
}
list
}
}

108
src/arm7tdmi/cpu.rs Normal file
View file

@ -0,0 +1,108 @@
use crate::num_traits::FromPrimitive;
use super::arm::*;
use super::sysbus::SysBus;
#[derive(Debug, PartialEq)]
pub enum CpuError {
IllegalInstruction,
}
pub type CpuResult<T> = Result<T, CpuError>;
#[derive(Debug, PartialEq)]
pub enum CpuState {
ARM,
THUMB,
}
#[derive(Debug, Primitive)]
#[repr(u8)]
enum CpuMode {
User = 0b10000,
Fiq = 0b10001,
Irq = 0b10010,
Supervisor = 0b10011,
Abort = 0b10111,
Undefined = 0b11011,
System = 0b11111,
}
pub struct CpuModeContext {
// r8-r14
banked_gpr: [u32; 7],
spsr: u32,
}
#[derive(Debug)]
pub struct Core {
pc: u32,
// r0-r7
gpr: [u32; 8],
cpsr: u32,
mode: CpuMode,
state: CpuState,
}
impl Core {
pub fn new() -> Core {
Core {
pc: 0,
gpr: [0; 8],
cpsr: 0,
mode: CpuMode::System,
state: CpuState::ARM,
}
}
pub fn get_reg(&self, reg_num: usize) -> u32 {
match reg_num {
0...7 => self.gpr[reg_num],
15 => self.pc,
_ => unimplemented!("TODO banked registers"),
}
}
pub fn set_reg(&mut self, reg_num: usize, val: u32) {
match reg_num {
0...7 => self.gpr[reg_num] = val,
15 => self.pc = val,
_ => unimplemented!("TODO banked registers"),
}
}
/// Resets the cpu
pub fn reset(&mut self) {
self.pc = 0;
self.cpsr = 0;
self.mode = CpuMode::System;
self.state = CpuState::ARM;
}
fn word_size(&self) -> usize {
match self.state {
CpuState::ARM => 4,
CpuState::THUMB => 2,
}
}
fn advance_pc(&mut self) {
self.pc = self.pc.wrapping_add(self.word_size() as u32)
}
fn step_arm(&mut self, sysbus: &mut SysBus) -> CpuResult<()> {
Err(CpuError::IllegalInstruction)
}
pub fn step(&mut self, sysbus: &mut SysBus) -> CpuResult<()> {
match self.state {
CpuState::ARM => self.step_arm(sysbus)?,
CpuState::THUMB => unimplemented!("thumb not implemented :("),
};
self.advance_pc();
Ok(())
}
}

View file

@ -1,12 +1,13 @@
pub mod arm;
pub use arm::arm_isa::ArmInstruction;
pub mod cpu;
pub use super::sysbus;
pub const REG_PC: usize = 15;
pub fn reg_string(reg: usize) -> &'static str {
let reg_names = &[
"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "fp", "ip", "sp",
"lr", "pc",
"r0", "r1", "r2", "r3", "r4", "r5", "r6", "r7", "r8", "r9", "r10", "fp", "ip", "sp", "lr",
"pc",
];
reg_names[reg]
}

20
src/cli.yml Normal file
View file

@ -0,0 +1,20 @@
name: rustboyadvance
author: Michel Heily <michelheily@gmail.com>
about: Game boy advance emulator
subcommands:
- debug:
about: debug the bios with the arm core emulation
args:
- BIOS:
help: Sets the bios file to use
required: false
default_value: gba_bios.bin
index: 1
- disass:
about: disassemble an arm binary file
args:
- INPUT:
help: Sets the input file to use
required: true
index: 1

View file

@ -1,69 +0,0 @@
use std::env;
use std::io;
use std::io::Cursor;
use std::io::prelude::*;
use std::fs::File;
use std::convert::TryFrom;
#[macro_use]
extern crate enum_primitive_derive;
extern crate num_traits;
extern crate bit;
extern crate byteorder;
use byteorder::{LittleEndian, ReadBytesExt};
mod arm7tdmi;
use arm7tdmi::ArmInstruction;
#[derive(Debug)]
pub enum DisassemblerError {
IO(io::Error),
}
impl From<io::Error> for DisassemblerError {
fn from(err: io::Error) -> DisassemblerError {
DisassemblerError::IO(err)
}
}
fn read_file(filename: &str) -> Result<Vec<u8>, DisassemblerError> {
let mut buf = Vec::new();
let mut file = File::open(filename)?;
file.read_to_end(&mut buf)?;
Ok(buf)
}
fn main() {
let filename = match env::args().nth(1) {
Some(filename) => filename,
None => panic!("usage: {} <file> <n>", env::args().nth(0).unwrap())
};
// let num_instructions = match env::args().nth(2) {
// Some(n) => n,
// None => panic!("usage: {} <file> <n>", env::args().nth(0).unwrap())
// }.parse::<usize>();
let buf = match read_file(&filename) {
Ok(buf) => buf,
Err(e) => panic!(e)
};
let mut rdr = Cursor::new(buf);
loop {
let value: u32 = match rdr.read_u32::<LittleEndian>() {
Ok(v) => v,
Err(err) => {
panic!("got an error {:?}", err);
}
};
let addr = (rdr.position() - 4) as u32;
print!("{:8x}:\t{:08x} \t", addr, value);
match ArmInstruction::try_from((value, addr)) {
Ok(insn) => println!("{}", insn),
Err(_) => println!("<UNDEFINED>")
}
}
}

View file

@ -1,3 +1,110 @@
fn main() {
println!("Hello, world!");
use std::convert::TryFrom;
use std::fs::File;
use std::io;
use std::io::prelude::*;
use std::io::ErrorKind;
#[macro_use]
extern crate enum_primitive_derive;
extern crate num_traits;
extern crate bit;
extern crate byteorder;
use byteorder::{LittleEndian, ReadBytesExt};
#[macro_use]
extern crate clap;
use clap::{App, ArgMatches};
pub mod sysbus;
use sysbus::SysBus;
mod arm7tdmi;
use arm7tdmi::arm;
use arm7tdmi::cpu;
#[derive(Debug)]
pub enum GBAError {
IO(io::Error),
ArmDecodeError(arm::ArmDecodeError),
CpuError(cpu::CpuError),
}
pub type GBAResult<T> = Result<T, GBAError>;
impl From<io::Error> for GBAError {
fn from(err: io::Error) -> GBAError {
GBAError::IO(err)
}
}
impl From<arm::ArmDecodeError> for GBAError {
fn from(err: arm::ArmDecodeError) -> GBAError {
GBAError::ArmDecodeError(err)
}
}
impl From<cpu::CpuError> for GBAError {
fn from(err: cpu::CpuError) -> GBAError {
GBAError::CpuError(err)
}
}
fn read_bin_file(filename: &str) -> GBAResult<Vec<u8>> {
let mut buf = Vec::new();
let mut file = File::open(filename)?;
file.read_to_end(&mut buf)?;
Ok(buf)
}
fn run_disass(matches: &ArgMatches) -> GBAResult<()> {
let input = matches.value_of("INPUT").unwrap();
let bin = read_bin_file(&input)?;
let mut rdr = io::Cursor::new(bin);
loop {
let value: u32 = match rdr.read_u32::<LittleEndian>() {
Ok(value) => Ok(value),
Err(e) => match e.kind() {
ErrorKind::UnexpectedEof => {
break;
}
_ => Err(e),
},
}?;
let addr = (rdr.position() - 4) as u32;
print!("{:8x}:\t{:08x} \t", addr, value);
match arm::ArmInstruction::try_from((value, addr)) {
Ok(insn) => println!("{}", insn),
Err(_) => println!("<UNDEFINED>"),
};
}
Ok(())
}
fn run_debug(matches: &ArgMatches) -> GBAResult<()> {
let gba_bios_path = matches.value_of("BIOS").unwrap_or_default();
println!("Loading BIOS: {}", gba_bios_path);
let bios_bin = read_bin_file(gba_bios_path)?;
let sysbus = SysBus::new(bios_bin);
let core = cpu::Core::new();
unimplemented!()
}
fn main() {
let yaml = load_yaml!("cli.yml");
let matches = App::from_yaml(yaml).get_matches();
let result = match matches.subcommand() {
("debug", Some(m)) => run_debug(m),
("disass", Some(m)) => run_disass(m),
_ => Ok(()),
};
if let Err(err) = result {
println!("Got an error: {:?}", err);
}
}

34
src/sysbus.rs Normal file
View file

@ -0,0 +1,34 @@
use byteorder::{LittleEndian, ReadBytesExt, WriteBytesExt};
const VIDEO_RAM_SIZE: usize = 128 * 1024;
const WORK_RAM_SIZE: usize = 256 * 1024;
const INTERNAL_RAM: usize = 32 * 1024;
const PALETTE_AM_SIZE: usize = 1 * 1024;
const OAM_SIZE: usize = 1 * 1024;
const BIOS_SIZE: usize = 16 * 1024;
const GAMEPAK_ROM_SIZE: usize = 32 * 1024 * 1024;
#[derive(Debug)]
pub struct SysBus {
bios_rom: Vec<u8>,
}
impl SysBus {
pub fn new(bios_rom: Vec<u8>) -> SysBus {
SysBus { bios_rom: bios_rom }
}
pub fn read_32(&self, addr: u32) -> u32 {
let addr = addr as usize;
(&self.bios_rom[addr..addr + 4])
.read_u32::<LittleEndian>()
.unwrap()
}
pub fn read_16(&self, addr: u32) -> u16 {
let addr = addr as usize;
(&self.bios_rom[addr..addr + 4])
.read_u16::<LittleEndian>()
.unwrap()
}
}