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authoriximeow <me@iximeow.net>2020-12-05 16:42:17 -0800
committeriximeow <me@iximeow.net>2020-12-06 11:58:57 -0800
commite30fee133cd0296bf3d0211e5ce13b5dfba03561 (patch)
treef7b966083f48d22b9969bab9ff7f4cdf1c71c8cd /src/armv7/thumb.rs
parent72f9a2500b2f2b65e61a5d19b3606225084c896d (diff)
fix some 32-bit thumb2 instructions, hook up .w, `s`, and a few typos
mostly confusion of pre/post-increment, operand widths, immediate widths, things of that nature
Diffstat (limited to 'src/armv7/thumb.rs')
-rw-r--r--src/armv7/thumb.rs240
1 files changed, 143 insertions, 97 deletions
diff --git a/src/armv7/thumb.rs b/src/armv7/thumb.rs
index d786305..93290a1 100644
--- a/src/armv7/thumb.rs
+++ b/src/armv7/thumb.rs
@@ -96,7 +96,8 @@ fn DecodeImmShift(reg: u8, ty: u8, imm5: u8) -> RegShift {
}
#[allow(non_snake_case)]
-pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut Instruction, bytes: T) -> Result<(), DecodeError> {
+pub fn decode_into<T: IntoIterator<Item=u8>>(decoder: &InstDecoder, inst: &mut Instruction, bytes: T) -> Result<(), DecodeError> {
+ inst.set_w(false);
let mut iter = bytes.into_iter();
let instr: u16 =
((iter.next().ok_or(DecodeError::ExhaustedInput)? as u16) ) |
@@ -106,14 +107,17 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `A6.1 Thumb instruction set encoding`
if opword >= 0b11101 {
+ inst.set_w(true);
+
+ // 32b instruction - `A6-228, 32-bit Thumb instruction encoding`
+ // opword low bits 01, 10, and 11 correspond to `op1` in table `A6-9`
+
let lower: u16 =
((iter.next().ok_or(DecodeError::ExhaustedInput)? as u16) ) |
((iter.next().ok_or(DecodeError::ExhaustedInput)? as u16) << 8 );
let op2 = (instr >> 5) & 0b1111111;
- // 32b instruction - `A6-228, 32-bit Thumb instruction encoding`
- // opword low bits 01, 10, and 11 correspond to `op1` in table `A6-9`
if opword < 0b11110 {
// op1 == 0b01
if op2 < 0b1000000 {
@@ -130,15 +134,18 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
let rd = ((lower >> 8) & 0b1111) as u8;
let rt = ((lower >> 12) & 0b1111) as u8;
+ // all only-wide, no w suffix
+ inst.set_w(false);
+
match op1op2 {
0b0000 => {
// `STREX` (`A8-691`)
// v6T2
if rd == 13 || rd == 15 || rt == 13 || rt == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if rd == rn || rd == rt {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::STREX;
inst.operands = [
@@ -159,7 +166,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `LDREX` (`A8-433`)
// v6T2
if rt == 13 || rt == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// TODO: should_is_must()
// rd == 0b1111
@@ -189,7 +196,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `if P == '0' && W == '0' then SEE "Related encodings"` -> this
// would imply tbb/tbh, should be unreachable
if rn == 15 || rt == 13 || rt == 15 || rd == 13 || rd == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::STRD;
inst.operands = [
@@ -214,10 +221,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `if P == '0' && W == '0' then SEE "Related encodings"` -> this
// would imply tbb/tbh, should be unreachable
if rt == 13 || rt == 15 || rd == 13 || rd == 15 || rd == rt {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if w && (rn == rt || rn == rd) {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if rn != 0b1111 {
// `LDRD (immediate)` (`A8-427`)
@@ -238,7 +245,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `LDRD (literal)` (`A8-429`)
// v6T2
if w {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// which because !(p == 0 && w == 0), we know p is true
inst.opcode = Opcode::LDRD;
@@ -260,10 +267,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0100 => {
// `STREXB` (`A8-693`)
if rd == 13 || rd == 15 || rt == 13 || rt == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if rd == rn || rd == rt {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// TODO: should_is_must()
// rt2 == 0b1111
@@ -278,10 +285,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0101 => {
// `STREXH` (`A8-693`)
if rd == 13 || rd == 15 || rt == 13 || rt == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if rd == rn || rd == rt {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// TODO: should_is_must()
// rt2 == 0b1111
@@ -296,10 +303,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0111 => {
// `STREXD` (`A8-693`)
if rd == 13 || rd == 15 || rt == 13 || rt == 15 || rt2 == 13 || rt2 == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if rd == rn || rd == rt || rd == rt2 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::STREXD;
inst.operands = [
@@ -366,7 +373,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0100 => {
// `LDREXB`
if rt == 13 || rt == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// TODO: should_is_must()
// rt2 == 0b1111
@@ -382,7 +389,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0101 => {
// `LDREXH`
if rt == 13 || rt == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// TODO: should_is_must()
// rt2 == 0b1111
@@ -398,7 +405,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0110 => {
// `LDREXD`
if rt == 13 || rt == 15 || rt2 == 13 || rt2 == 15 || rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// TODO: should_is_must()
// rd == 0b1111
@@ -428,7 +435,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `if P == '0' && W == '0' then SEE "Related encodings"` -> this
// would imply tbb/tbh, should be unreachable
if rn == 15 || rt == 13 || rt == 15 || rd == 13 || rd == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::STRD;
inst.operands = [
@@ -456,10 +463,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `if P == '0' && W == '0' then SEE "Related encodings"` -> this
// would imply tbb/tbh, should be unreachable
if rt == 13 || rt == 15 || rd == 13 || rd == 15 || rd == rt {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if w && (rn == rt || rn == rd) {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if rn != 0b1111 {
// `LDRD (immediate)` (`A8-427`)
@@ -469,10 +476,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
Operand::Reg(Reg::from_u8(rt)),
Operand::Reg(Reg::from_u8(rd)),
if p {
- Operand::RegDerefPreindexOffset(Reg::from_u8(rn), imm8 << 2, u, w)
+ Operand::RegDerefPostindexOffset(Reg::from_u8(rn), imm8 << 2, u, w)
} else {
// p == 0 and w == 0 is impossible, would be tbb/tbh
- Operand::RegDerefPostindexOffset(Reg::from_u8(rn), imm8 << 2, u, false)
+ Operand::RegDerefPreindexOffset(Reg::from_u8(rn), imm8 << 2, u, false)
},
Operand::Nothing,
];
@@ -480,7 +487,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `LDRD (literal)` (`A8-429`)
// v6T2
if w {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
// which because !(p == 0 && w == 0), we know p is true
inst.opcode = Opcode::LDRD;
@@ -517,14 +524,14 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `STM (STMIA, STMEA)` (`A8-665`)
// v6T2
if rn == 15 || lower.count_ones() < 2 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if w && (lower & (1 << rn)) != 0 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::STM(
true, // add
- true, // preincrement
+ false, // preincrement
w, // wback
true, // usermode
);
@@ -538,11 +545,15 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b10 => {
// `STMDB`/`STMFD` (`A8-669`)
// or `PUSH` (`A8-539`)
+
+ // implied by instruction?
+ inst.set_w(false);
+
if w && rn == 0b1101 {
// `PUSH`
// v6T2
if lower.count_ones() < 2 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::PUSH;
inst.operands = [
@@ -555,10 +566,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `STMDB`
// v6T2
if rn == 15 || lower.count_ones() < 2 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if w && (lower & (1 << rn)) != 0 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::STM(
false, // decrement
@@ -596,7 +607,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `RFE` (`B9-1986`)
// v6T2
if rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::RFE(false, true);
inst.operands = [
@@ -611,7 +622,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if w && rn == 0b1101 {
// `POP` (`A8-535`)
if lower.count_ones() < 2 || (lower & 0xc000) == 0xc000 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::POP;
inst.operands = [
@@ -623,12 +634,12 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `LDM/LDMIA/LDMFD`
if rn == 15 || lower.count_ones() < 2 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if w && (lower & (1 << rn)) != 0 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
- inst.opcode = Opcode::LDM(true, true, w, true);
+ inst.opcode = Opcode::LDM(true, false, w, true);
inst.operands = [
Operand::RegWBack(Reg::from_u8(rn), w),
Operand::RegList(lower),
@@ -639,11 +650,15 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
}
0b10 => {
// `LDMDB/LDMEA` (`A8-403`)
+
+ // wide is implied
+ inst.set_w(false);
+
if rn == 15 || lower.count_ones() < 2 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
if w && (lower & (1 << rn)) != 0 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::LDM(false, true, w, true);
inst.operands = [
@@ -657,7 +672,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// `RFE` (`B9-1986`)
// v6T2
if rn == 15 {
- todo!("UNPREDICTABLE");
+ decoder.unpredictable()?;
}
inst.opcode = Opcode::RFE(true, false);
inst.operands = [
@@ -694,11 +709,14 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
);
let shift = Operand::RegShift(shift);
+ inst.s = s;
+
match op {
0b0000 => {
if rd == 0b1111 && s {
// `TST` (`A8-747`)
// v6T2
+ inst.s = false;
inst.opcode = Opcode::TST;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -709,7 +727,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `AND` (`A8-324`)
// v6T2
- // TODO: S
inst.opcode = Opcode::AND;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -722,7 +739,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0001 => {
// `BIC` (`A8-340`)
// v6T2
- // TODO: S
inst.opcode = Opcode::BIC;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -771,7 +787,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `ORR` (`A8-519`)
// v6T2
- // TODO: S
inst.opcode = Opcode::ORR;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -785,7 +800,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rn == 0b1111 {
// `MVN` (`A8-507`)
// v6T2
- // TODO: S
inst.opcode = Opcode::MVN;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -796,7 +810,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `ORN` (`A8-515`)
// v6T2
- // TODO: S
inst.opcode = Opcode::ORN;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -810,6 +823,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rd == 0b1111 && s {
// `TEQ` (`A8-741`)
// v6T2
+ inst.s = false;
inst.opcode = Opcode::TEQ;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -820,7 +834,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `EOR` (`A8-385`)
// v6T2
- // TODO: S
inst.opcode = Opcode::EOR;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -835,7 +848,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
// v6T2
// TODO: fix shift
// TODO: check opcode
- // TODO: S
+ inst.s = false;
inst.opcode = if lower & 0b10000 != 0 {
Opcode::PKHTB
} else {
@@ -852,6 +865,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rd == 0b1111 && s {
// `CMN` (`A8-364`)
// v6T2
+ inst.s = false;
inst.opcode = Opcode::CMN;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -861,7 +875,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
];
} else {
// `ADD` (`A8-308`)
- // TODO: S
inst.opcode = Opcode::ADD;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -874,7 +887,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b1010 => {
// `ADC` (`A8-300`)
// v6T2
- // TODO: S
inst.opcode = Opcode::ADC;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -886,7 +898,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b1011 => {
// `SBC` (`A8-595`)
// v6T2
- // TODO: S
inst.opcode = Opcode::SBC;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -899,6 +910,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rd == 0b1111 && s {
// `CMP` (`A8-370`)
// v6T2
+ inst.s = false;
inst.opcode = Opcode::CMP;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -909,7 +921,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `SUB` (`A8-713`)
// v6T2
- // TODO: S
inst.opcode = Opcode::SUB;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -959,6 +970,8 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
let imm8 = lower & 0b11111111;
let imm = (i << 11) | (imm3 << 8) | imm8;
+ inst.s = s;
+
let imm = ThumbExpandImm_C(imm);
match op {
@@ -966,6 +979,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rd == 0b1111 && s {
// `TST` (`A8-745`)
// v6T2
+ inst.s = false;
inst.opcode = Opcode::TST;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -976,7 +990,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `AND` (`A8-322`)
// v6T2
- // TODO: S
inst.opcode = Opcode::AND;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -989,7 +1002,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b0001 => {
// `BIC` (`A8-338`)
// v6T2
- // TODO: S
inst.opcode = Opcode::BIC;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1002,7 +1014,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rn == 0b1111 {
// `MOV` (`A8-485`)
// v6T2
- // TODO: S
inst.opcode = Opcode::MOV;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1013,7 +1024,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `ORR` (`A8-517`)
// v6T2
- // TODO: S
inst.opcode = Opcode::ORR;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1027,7 +1037,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rn == 0b1111 {
// `MVN` (`A8-505`)
// v6T2
- // TODO: S
inst.opcode = Opcode::MOV;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1038,7 +1047,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `ORN` (`A8-513`)
// v6T2
- // TODO: S
inst.opcode = Opcode::ORN;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1052,7 +1060,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rd == 0b1111 && s {
// `TEQ` (`A8-739`)
// v6T2
- // TODO: S
+ inst.s = false;
inst.opcode = Opcode::TEQ;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -1063,7 +1071,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `EOR` (`A8-383`)
// v6T2
- // TODO: S
inst.opcode = Opcode::EOR;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1077,7 +1084,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rd == 0b1111 && s {
// `CMN` (`A8-362`)
// v6T2
- // TODO: S
+ inst.s = false;
inst.opcode = Opcode::CMN;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -1088,7 +1095,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `ADD` (`A8-304`)
// v6T2
- // TODO: S
inst.opcode = Opcode::ADD;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1101,7 +1107,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b1010 => {
// `ADC` (`A8-298`)
// v6T2
- // TODO: S
inst.opcode = Opcode::ADC;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1113,7 +1118,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b1011 => {
// `SBC` (`A8-593`)
// v6T2
- // TODO: S
inst.opcode = Opcode::SBC;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1126,7 +1130,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if rd == 0b1111 && s {
// `CMP` (`A8-368`)
// v6T2
- // TODO: S
+ inst.s = false;
inst.opcode = Opcode::CMP;
inst.operands = [
Operand::Reg(Reg::from_u8(rn)),
@@ -1137,7 +1141,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
// `SUB` (`A8-709`)
// v6T2
- // TODO: S
inst.opcode = Opcode::SUB;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1150,7 +1153,6 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b1110 => {
// `RSB` (`A8-575`)
// v6T2
- // TODO: S
inst.opcode = Opcode::RSB;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
@@ -1289,6 +1291,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b10100 => {
// `SBFX` (`A8-599`)
// v6T2
+
+ // wide is implied
+ inst.set_w(false);
+
inst.opcode = Opcode::SBFX;
let imm3_2 = ((lower >> 10) & 0b11100) | ((lower >> 6) & 0b11);
inst.operands = [
@@ -1334,7 +1340,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
inst.opcode = Opcode::USAT;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
- Operand::Imm32((lower & 0b1111) as u32),
+ Operand::Imm32((lower & 0b11111) as u32),
Operand::RegShift(shift),
Operand::Nothing,
];
@@ -1349,7 +1355,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
inst.opcode = Opcode::USAT;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
- Operand::Imm32((lower & 0b1111) as u32),
+ Operand::Imm32((lower & 0b11111) as u32),
Operand::RegShift(shift),
Operand::Nothing,
];
@@ -1359,7 +1365,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
inst.opcode = Opcode::USAT16;
inst.operands = [
Operand::Reg(Reg::from_u8(rd)),
- Operand::Imm32((lower & 0b1111) as u32),
+ Operand::Imm32((lower & 0b11111) as u32),
Operand::Reg(Reg::from_u8(rn)),
Operand::Nothing,
];
@@ -1368,6 +1374,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
0b11100 => {
// `UBFX` (`A8-757`)
// v6T2
+
+ // wide is implied
+ inst.set_w(false);
+
inst.opcode = Opcode::UBFX;
let imm3_2 = ((lower >> 10) & 0b11100) | ((lower >> 6) & 0b11);
inst.operands = [
@@ -1432,7 +1442,10 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
let mask = (lower >> 10) & 0b11;
let spec_reg = match mask {
0b00 => {
- todo!("UNPREDICTABLE");
+ // TODO: generally "unpredictable" is
+ // overridden by DecodeMode::Any but there's
+ // nothing to salvage here?
+ return Err(DecodeError::Unpredictable);
}
0b01 => {
StatusRegMask::APSR_G
@@ -1920,13 +1933,22 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
];
} else {
// `STRB (immediate, Thumb)` (`A8-679`)
- // encoding T3
+ // encoding T2/T3
// v6T2
- let imm8 = lower & 0b1111_1111;
- let puw = (lower >> 8) & 0b111;
- let p = puw & 0b100 != 0;
- let u = puw & 0b010 != 0;
- let w = puw & 0b001 != 0;
+ let (imm, p, u, w) = if has_imm12 {
+ let imm12 = lower & 0b1111_1111_1111;
+ let p = true;
+ let u = true;
+ let w = false;
+ (imm12, p, u, w)
+ } else {
+ let imm8 = lower & 0b1111_1111;
+ let puw = (lower >> 8) & 0b111;
+ let p = puw & 0b100 != 0;
+ let u = puw & 0b010 != 0;
+ let w = puw & 0b001 != 0;
+ (imm8, p, u, w)
+ };
// assert!(puw != 0b110) // would be `strbt`
let rt = ((lower >> 12) & 0b1111) as u8;
inst.opcode = Opcode::STRB;
@@ -1936,14 +1958,14 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if p {
Operand::RegDerefPreindexOffset(
Reg::from_u8(rn),
- imm8,
+ imm,
u, // add
w, // wback
)
} else {
Operand::RegDerefPostindexOffset(
Reg::from_u8(rn),
- imm8,
+ imm,
u, // add
w, // wback
)
@@ -1997,13 +2019,22 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
];
} else {
// `STRH (immediate, Thumb)` (`A8-699`)
- // encoding T3
+ // encoding T2/T3
// v6T2
- let imm8 = lower & 0b1111_1111;
- let puw = (lower >> 8) & 0b111;
- let p = puw & 0b100 != 0;
- let u = puw & 0b010 != 0;
- let w = puw & 0b001 != 0;
+ let (imm, p, u, w) = if has_imm12 {
+ let imm12 = lower & 0b1111_1111_1111;
+ let p = true;
+ let u = true;
+ let w = false;
+ (imm12, p, u, w)
+ } else {
+ let imm8 = lower & 0b1111_1111;
+ let puw = (lower >> 8) & 0b111;
+ let p = puw & 0b100 != 0;
+ let u = puw & 0b010 != 0;
+ let w = puw & 0b001 != 0;
+ (imm8, p, u, w)
+ };
// assert!(puw != 0b110) // would be `strbt`
let rt = ((lower >> 12) & 0b1111) as u8;
inst.opcode = Opcode::STRH;
@@ -2013,14 +2044,14 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if p {
Operand::RegDerefPreindexOffset(
Reg::from_u8(rn),
- imm8,
+ imm,
u, // add
w, // wback
)
} else {
Operand::RegDerefPostindexOffset(
Reg::from_u8(rn),
- imm8,
+ imm,
u, // add
w, // wback
)
@@ -2074,13 +2105,22 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
];
} else {
// `STR (immediate, Thumb)` (`A8-673`)
- // encoding T4
+ // encoding T3/T4
// v6T2
- let imm8 = lower & 0b1111_1111;
- let puw = (lower >> 8) & 0b111;
- let p = puw & 0b100 != 0;
- let u = puw & 0b010 != 0;
- let w = puw & 0b001 != 0;
+ let (imm, p, u, w) = if has_imm12 {
+ let imm12 = lower & 0b1111_1111_1111;
+ let p = true;
+ let u = true;
+ let w = false;
+ (imm12, p, u, w)
+ } else {
+ let imm8 = lower & 0b1111_1111;
+ let puw = (lower >> 8) & 0b111;
+ let p = puw & 0b100 != 0;
+ let u = puw & 0b010 != 0;
+ let w = puw & 0b001 != 0;
+ (imm8, p, u, w)
+ };
// assert!(puw != 0b110) // would be `strbt`
let rt = ((lower >> 12) & 0b1111) as u8;
inst.opcode = Opcode::STR;
@@ -2090,14 +2130,14 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
if p {
Operand::RegDerefPreindexOffset(
Reg::from_u8(rn),
- imm8,
+ imm,
u, // add
w, // wback
)
} else {
Operand::RegDerefPostindexOffset(
Reg::from_u8(rn),
- imm8,
+ imm,
u, // add
w, // wback
)
@@ -2211,24 +2251,30 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
} else {
if op2 < 0b0100 {
// `Parallel addition and subtraction, signed`
+ return Err(DecodeError::Incomplete);
} else if op2 < 0b1000 {
// `Parallel addition and subtraction, unsigned` (`A6-244`)
+ return Err(DecodeError::Incomplete);
} else if op2 < 0b1100 {
// `Miscellaneous operations` (`A6-246`)
+ return Err(DecodeError::Incomplete);
} else {
return Err(DecodeError::Undefined);
}
}
} else {
- if op2 & 0b0001000 == 0 {
- // `Multiply, multiply accumulate, and absolute difference` (`A6-247`)
- } else {
+ if op2 & 0b0001000 != 0 {
// `Long multiply, long multiply accumulate, and divide` (`A6-248`)
+ return Err(DecodeError::Incomplete);
+ } else {
+ // `Multiply, multiply accumulate, and absolute difference` (`A6-247`)
+ return Err(DecodeError::Incomplete);
}
}
}
} else {
// `Coprocessor, Advanced SIMD, and Floating-point instructions` (`A6-249`)
+ return Err(DecodeError::Incomplete);
}
}
} else {
@@ -3040,7 +3086,7 @@ pub fn decode_into<T: IntoIterator<Item=u8>>(_decoder: &InstDecoder, inst: &mut
let rn = ((instr >> 8) & 0b111) as u8;
let reglist = instr & 0b1111_1111;
let w = (reglist & (1 << rn)) == 0;
- inst.opcode = Opcode::LDM(true, true, false, true); // ldmia, no wback, yes usermode
+ inst.opcode = Opcode::LDM(true, false, false, true); // ldmia, no wback, yes usermode
inst.operands = [
Operand::RegWBack(Reg::from_u8(rn), w),
Operand::RegList(reglist as u16),
generated by cgit v1.1 at 2024-11-01 04:32:31 +0000