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-rw-r--r--src/lib.rs467
1 files changed, 467 insertions, 0 deletions
diff --git a/src/lib.rs b/src/lib.rs
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+++ b/src/lib.rs
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+extern crate yaxpeax_arch;
+
+use yaxpeax_arch::{Arch, Decodable, LengthedInstruction};
+
+pub mod consts;
+pub mod display;
+
+pub struct PIC18;
+impl Arch for PIC18 {
+ type Address = u32;
+ type Instruction = Instruction;
+ type Operand = Operand;
+}
+
+#[derive(Debug, Copy, Clone)]
+pub struct Instruction {
+ pub opcode: Opcode,
+ pub operands: [Operand; 2]
+}
+
+impl LengthedInstruction for Instruction {
+ type Unit = <PIC18 as Arch>::Address;
+ fn len(&self) -> Self::Unit {
+ match self.opcode {
+ Opcode::MOVFF
+ | Opcode::MOVSF
+ | Opcode::MOVSD
+ | Opcode::CALL
+ | Opcode::LFSR
+ | Opcode::GOTO => {
+ 4
+ },
+ _ => 2
+ }
+ }
+}
+
+impl Instruction {
+ pub fn blank() -> Instruction {
+ Instruction {
+ opcode: Opcode::NOP,
+ operands: [Operand::Nothing, Operand::Nothing]
+ }
+ }
+}
+
+#[allow(non_camel_case_types)]
+#[derive(Debug, Copy, Clone)]
+pub enum Opcode {
+ Invalid(u8, u8),
+ NOP,
+ MOVFF,
+ MOVSF,
+ MOVSD,
+ CALL,
+ LFSR,
+ GOTO,
+ CALLW,
+ CLRWDT,
+ DAW,
+ POP,
+ PUSH,
+ RESET,
+ RETFIE,
+ RETFIE_FAST,
+ RETURN,
+ RETURN_FAST,
+ SLEEP,
+ TBLRD_I_S,
+ TBLRD_S,
+ TBLRD_S_D,
+ TBLRD_S_I,
+ TBLWT_I_S,
+ TBLWT_S,
+ TBLWT_S_D,
+ TBLWT_S_I,
+ MOVLB,
+ ADDLW,
+ MOVLW,
+ MULLW,
+ RETLW,
+ ANDLW,
+ XORLW,
+ IORLW,
+ SUBLW,
+ IORWF,
+ ANDWF,
+ XORWF,
+ COMF,
+ MULWF,
+ ADDWFC,
+ ADDWF,
+ INCF,
+ DECF,
+ DECFSZ,
+ RRCF,
+ RLCF,
+ SWAPF,
+ INCFSZ,
+ RRNCF,
+ RLNCF,
+ INFSNZ,
+ DCFSNZ,
+ MOVF,
+ SUBFWB,
+ SUBWFB,
+ SUBWF,
+ CPFSLT,
+ CPFSEQ,
+ CPFSGT,
+ TSTFSZ,
+ SETF,
+ CLRF,
+ NEGF,
+ MOVWF,
+ BTG,
+ BSF,
+ BCF,
+ BTFSS,
+ BTFSC,
+ BZ,
+ BNZ,
+ BC,
+ BNC,
+ BOV,
+ BNOV,
+ BN,
+ BNN,
+ BRA,
+ RCALL
+}
+
+#[derive(Debug, Copy, Clone)]
+pub enum Operand {
+ ImmediateU8(u8),
+ ImmediateU32(u32),
+ FileFSR(u8),
+ File(u8, bool), // a == banked
+ AbsoluteFile(u16),
+ RedirectableFile(u8, bool, bool), // a == banked, d == direction
+ Nothing
+}
+
+impl Decodable for Instruction {
+ fn decode<'a, T: IntoIterator<Item=&'a u8>>(bytes: T) -> Option<Self> {
+ let mut blank = Instruction::blank();
+ match blank.decode_into(bytes) {
+ Some(_) => Some(blank),
+ None => None
+ }
+ }
+ fn decode_into<'a, T: IntoIterator<Item=&'a u8>>(&mut self, bytes: T) -> Option<()> {
+ let mut bytes_iter = bytes.into_iter();
+ let word: Vec<&'a u8> = bytes_iter.by_ref().take(2).collect();
+ if word.len() != 2 {
+ return None;
+ }
+
+// println!("Decoding {:x?}", word);
+ match *word[1] {
+ 0x00 => {
+ match *word[0] {
+ 0x00 => {
+ self.opcode = Opcode::NOP;
+ Some(())
+ },
+ 0b00000011 => {
+ self.opcode = Opcode::SLEEP;
+ Some(())
+ },
+ 0b00000100 => {
+ self.opcode = Opcode::CLRWDT;
+ Some(())
+ },
+ 0b00000101 => {
+ self.opcode = Opcode::PUSH;
+ Some(())
+ },
+ 0b00000110 => {
+ self.opcode = Opcode::POP;
+ Some(())
+ },
+ 0b00000111 => {
+ self.opcode = Opcode::DAW;
+ Some(())
+ },
+ 0b00001000 => {
+ self.opcode = Opcode::TBLRD_S;
+ Some(())
+ },
+ 0b00001001 => {
+ self.opcode = Opcode::TBLRD_S_I;
+ Some(())
+ },
+ 0b00001010 => {
+ self.opcode = Opcode::TBLRD_S_D;
+ Some(())
+ },
+ 0b00001011 => {
+ self.opcode = Opcode::TBLRD_I_S;
+ Some(())
+ },
+ 0b00001100 => {
+ self.opcode = Opcode::TBLWT_S;
+ Some(())
+ },
+ 0b00001101 => {
+ self.opcode = Opcode::TBLWT_S_I;
+ Some(())
+ },
+ 0b00001110 => {
+ self.opcode = Opcode::TBLWT_S_D;
+ Some(())
+ },
+ 0b00001111 => {
+ self.opcode = Opcode::TBLWT_I_S;
+ Some(())
+ },
+ 0b00010000 => {
+ self.opcode = Opcode::RETFIE;
+ Some(())
+ },
+ 0b00010001 => {
+ self.opcode = Opcode::RETFIE_FAST;
+ Some(())
+ },
+ 0b00010010 => {
+ self.opcode = Opcode::RETURN;
+ Some(())
+ },
+ 0b00010011 => {
+ self.opcode = Opcode::RETURN_FAST;
+ Some(())
+ },
+ 0b00010100 => {
+ self.opcode = Opcode::CALLW;
+ Some(())
+ },
+ 0b11111111 => {
+ self.opcode = Opcode::RESET;
+ Some(())
+ },
+ _ => {
+ self.opcode = Opcode::Invalid(*word[0], *word[1]);
+ None
+ }
+ }
+ },
+ 0x01 => {
+ self.opcode = Opcode::MOVLB;
+ // this ignores high nibble of low word. ok by isa, but...
+ self.operands[0] = Operand::ImmediateU8(*word[0] & 0x0f);
+ Some(())
+ },
+ 0x02 | 0x03 => {
+ self.opcode = Opcode::MULWF;
+ let a = (word[1] & 0x01) == 1;
+ self.operands[0] = Operand::File(*word[0], a);
+ Some(())
+ },
+ 0x04 | 0x05 | 0x06 | 0x07 => {
+ self.opcode = Opcode::DECF;
+ let d = ((word[1] >> 1) & 0x01u8) == 1u8;
+ let a = (word[1] & 0x01) == 1;
+ self.operands[0] = Operand::RedirectableFile(*word[0], a, d);
+ Some(())
+ },
+ 0x08 => {
+ self.opcode = Opcode::SUBLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0x09 => {
+ self.opcode = Opcode::IORLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0x0a => {
+ self.opcode = Opcode::XORLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0x0b => {
+ self.opcode = Opcode::ANDLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0x0c => {
+ self.opcode = Opcode::RETLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0x0d => {
+ self.opcode = Opcode::MULLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0x0e => {
+ self.opcode = Opcode::MOVLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0x0f => {
+ self.opcode = Opcode::ADDLW;
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ x if x >= 0x10 && x < 0b01100000 => {
+ let da = x & 0b0011;
+ let opc = (x >> 2) - 4;
+ self.opcode = [
+ Opcode::IORWF,
+ Opcode::ANDWF,
+ Opcode::XORWF,
+ Opcode::COMF,
+ Opcode::ADDWFC,
+ Opcode::ADDWF,
+ Opcode::INCF,
+ Opcode::DECFSZ,
+ Opcode::RRCF,
+ Opcode::RLCF,
+ Opcode::SWAPF,
+ Opcode::INCFSZ,
+ Opcode::RRNCF,
+ Opcode::RLNCF,
+ Opcode::INFSNZ,
+ Opcode::DCFSNZ,
+ Opcode::MOVF,
+ Opcode::SUBFWB,
+ Opcode::SUBWFB,
+ Opcode::SUBWF
+ ][opc as usize];
+ self.operands[0] = Operand::RedirectableFile(*word[0], (da & 0x01) == 0x01, (da & 0x02) == 0x02);
+ Some(())
+ },
+ x if x >= 0b01100000 && x < 0b01110000 => {
+ let a = x & 1;
+ let opc = (x >> 1) & 0b0000111;
+ self.opcode = [
+ Opcode::CPFSLT,
+ Opcode::CPFSEQ,
+ Opcode::CPFSGT,
+ Opcode::TSTFSZ,
+ Opcode::SETF,
+ Opcode::CLRF,
+ Opcode::NEGF,
+ Opcode::MOVWF
+ ][opc as usize];
+ self.operands[0] = Operand::File(*word[0], a == 1);
+ Some(())
+ },
+ x if x >= 0b01110000 && x < 0b11000000 => {
+ let a = x & 1;
+ let opc = ((x >> 4) & 0b00001111) - 0b111;
+ self.opcode = [
+ Opcode::BTG,
+ Opcode::BSF,
+ Opcode::BCF,
+ Opcode::BTFSS,
+ Opcode::BTFSC
+ ][opc as usize];
+ let bit = (x >> 1) & 0b0000111;
+ self.operands[0] = Operand::File(*word[0], a == 1);
+ self.operands[1] = Operand::ImmediateU8(bit);
+ Some(())
+ },
+ x if x >= 0b11000000 && x < 0b11010000 => {
+ self.opcode = Opcode::MOVFF;
+ let word2: Vec<&'a u8> = bytes_iter.take(2).collect();
+ if word2.len() != 2 {
+ return None;
+ }
+ if word2[1] & 0xf0 != 0xf0 {
+ return None;
+ }
+
+ let src = (*word[0] as u16) | ((*word[1] as u16 & 0x0f) << 8);
+ let dest = (*word2[0] as u16) | ((*word2[1] as u16 & 0x0f) << 8);
+ self.operands[0] = Operand::AbsoluteFile(src);
+ self.operands[1] = Operand::AbsoluteFile(dest);
+ Some(())
+ },
+ x if x >= 0b11010000 && x < 0b11100000 => {
+ self.opcode = [
+ Opcode::BRA,
+ Opcode::RCALL
+ ][((x >> 3) & 1) as usize];
+ self.operands[0] = Operand::ImmediateU32((((x & 0b111) as u32) << 8) | *word[0] as u32);
+ Some(())
+ },
+ x if x >= 0b11100000 && x < 0b11101000 => {
+ let opc = x & 0b00000111;
+ self.opcode = [
+ Opcode::BZ,
+ Opcode::BNZ,
+ Opcode::BC,
+ Opcode::BNC,
+ Opcode::BOV,
+ Opcode::BNOV,
+ Opcode::BN,
+ Opcode::BNN
+ ][opc as usize];
+ self.operands[0] = Operand::ImmediateU8(*word[0]);
+ Some(())
+ },
+ 0xee => {
+ let f_k_msb = *word[0];
+ let word2: Vec<&'a u8> = bytes_iter.take(2).collect();
+ if word2.len() != 2 {
+ return None;
+ }
+
+ if (word2[1] & 0xf0) != 0xf0 {
+ return None; // invalid instruction
+ }
+
+ self.opcode = Opcode::LFSR;
+
+ let f = (f_k_msb >> 4) & 0b0011;
+ let k_msb = f_k_msb & 0b1111;
+ let k_lsb = word2[0];
+
+ self.operands[0] = Operand::FileFSR(f);
+ self.operands[1] = Operand::ImmediateU32(((k_msb as u32) << 8) | (*k_lsb as u32));
+ Some(())
+ }
+ /* ... */
+ 0xeb | 0xec => {
+ // TODO: respect s bit
+ let k_lsb = *word[0];
+ let word2: Vec<&'a u8> = bytes_iter.take(2).collect();
+ if word2.len() != 2 {
+ return None;
+ }
+
+ if (word2[1] & 0xf0) != 0xf0 {
+ return None; // invalid instruction
+ }
+
+ let k_msb = (((*word2[1] & 0xf) as u32) << 8) | *word2[0] as u32;
+
+ self.opcode = Opcode::CALL;
+ self.operands[0] = Operand::ImmediateU32(((k_msb << 8) | k_lsb as u32) << 1);
+ Some(())
+ }
+ 0xef => {
+ let k_lsb = *word[0];
+ let word2: Vec<&'a u8> = bytes_iter.take(2).collect();
+ if word2.len() != 2 {
+ return None;
+ }
+
+ if (word2[1] & 0xf0) != 0xf0 {
+ return None; // invalid instruction
+ }
+
+ let k_msb = (((*word2[1] & 0xf) as u32) << 8) | *word2[0] as u32;
+
+ self.opcode = Opcode::GOTO;
+ self.operands[0] = Operand::ImmediateU32(((k_msb << 8) | k_lsb as u32) << 1);
+ Some(())
+ }
+ _ => None
+ }
+ }
+}
+
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