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Diffstat (limited to 'src/cpu/isa_teq.rs')
| -rw-r--r-- | src/cpu/isa_teq.rs | 45 |
1 files changed, 45 insertions, 0 deletions
diff --git a/src/cpu/isa_teq.rs b/src/cpu/isa_teq.rs new file mode 100644 index 0000000..2bc162a --- /dev/null +++ b/src/cpu/isa_teq.rs @@ -0,0 +1,45 @@ +/* + Copyright 2021-2023 Gabriel Jensen. + + This file is part of Luma. + + Luma is free software: you can redistribute it + and/or modify it under the terms of the GNU + Affero General Public License as published by + the Free Software Foundation, either version 3 + of the License, or (at your option) any later + version. + + Luma is distributed in the hope that it will be + useful, but WITHOUT ANY WARRANTY; without even + the implied warranty of MERCHANTABILITY or + FITNESS FOR A PARTICULAR PURPOSE. See the GNU + Affero General Public License for more details. + + You should have received a copy of the GNU + Affero General Public License along with Luma. + If not, see <https://www.gnu.org/licenses/>. +*/ + +use crate::log; +use crate::cpu::{Cpu, take_state_mut}; +use crate::shifter::Shifter; + +impl Cpu { + pub(super) fn isa_teq(&mut self, rn: u8, shifter: Shifter) { + log!("teq r{rn}, {shifter}"); + + take_state_mut!(state, self); + + let rn_value = state.read_register(rn); + let (mask, c) = state.shifter_value(shifter); + + let temporary = rn_value ^ mask; + + let mut cpsr = state.read_cpsr() & 0b00011111111111111111111111111111; + cpsr |= (c as u32) << 0x1D; + cpsr |= ((temporary == 0x0) as u32) << 0x1E; + cpsr |= temporary & 0b10000000000000000000000000000000; + state.write_cpsr(cpsr); + } +} |