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authortaitep <taitep@taitep.se>2025-10-21 14:46:02 +0200
committertaitep <taitep@taitep.se>2025-10-21 14:46:02 +0200
commit9c4e2d17a2fda196cb5e936ae0693cdc1ee0b2f1 (patch)
tree7e18be388a623419305c04bd9b575e06d9f7492c /src/instructions
parent19568f855eca24f52e7db3bab44676086fbd2ac1 (diff)
Add support for addiw and lui
Diffstat (limited to 'src/instructions')
-rw-r--r--src/instructions/opcodes.rs1
-rw-r--r--src/instructions/rvi.rs31
2 files changed, 27 insertions, 5 deletions
diff --git a/src/instructions/opcodes.rs b/src/instructions/opcodes.rs
index 7115820..b5613f9 100644
--- a/src/instructions/opcodes.rs
+++ b/src/instructions/opcodes.rs
@@ -1,5 +1,6 @@
//! Opcodes (unless compressed) have the last 2 bits stripped off as they are always 1s for non-compressed instructions.
pub(super) const OP_IMM: u8 = 0b00100;
+pub(super) const OP_IMM_32: u8 = 0b00110;
pub(super) const STORE: u8 = 0b01000;
diff --git a/src/instructions/rvi.rs b/src/instructions/rvi.rs
index f82f1b3..365b133 100644
--- a/src/instructions/rvi.rs
+++ b/src/instructions/rvi.rs
@@ -5,17 +5,22 @@ use crate::{
instructions::{
OpcodeHandler,
gen_tools::insert_funct3_splitter,
- opcodes::{OP_IMM, STORE},
+ opcodes::{OP_IMM, OP_IMM_32, STORE},
},
mem::PageNum,
};
pub(super) fn add_instrs(list: &mut [OpcodeHandler; 32]) {
- let funct3_split_op_imm = insert_funct3_splitter(&mut list[OP_IMM as usize].splitter);
- funct3_split_op_imm[0b000].handler = Some(super::InstructionHandler { runner: addi }); // ADDI
+ let funct3_splitter = insert_funct3_splitter(&mut list[OP_IMM as usize].splitter); // OP-IMM
+ funct3_splitter[0b000].handler = Some(super::InstructionHandler { runner: addi }); // ADDI
- let funct3_split_store = insert_funct3_splitter(&mut list[STORE as usize].splitter);
- funct3_split_store[0b011].handler = Some(super::InstructionHandler { runner: sd }) // SD
+ let funct3_splitter = insert_funct3_splitter(&mut list[OP_IMM_32 as usize].splitter); // OP-IMM-32
+ funct3_splitter[0b000].handler = Some(super::InstructionHandler { runner: addiw }); //ADDIW
+
+ let funct3_splitter = insert_funct3_splitter(&mut list[STORE as usize].splitter); // STORE
+ funct3_splitter[0b011].handler = Some(super::InstructionHandler { runner: sd }); // SD
+
+ list[0b01101].handler = Some(super::InstructionHandler { runner: lui }); //LUI
}
fn addi(core: &mut Core, instr: Instruction) -> InstructionResult {
@@ -29,6 +34,16 @@ fn addi(core: &mut Core, instr: Instruction) -> InstructionResult {
InstructionResult::Normal
}
+fn addiw(core: &mut Core, instr: Instruction) -> InstructionResult {
+ let res = core.reg_read(instr.rs1()).wrapping_add(instr.imm_i()) as i32;
+
+ core.reg_write(instr.rd(), res as i64 as u64);
+
+ core.pc = core.pc.wrapping_add(4);
+
+ InstructionResult::Normal
+}
+
// TODO: Support misaligned memory access
fn sd(core: &mut Core, instr: Instruction) -> InstructionResult {
let addr = core.reg_read(instr.rs1()).wrapping_add(instr.imm_s());
@@ -49,3 +64,9 @@ fn sd(core: &mut Core, instr: Instruction) -> InstructionResult {
Err(_) => InstructionResult::Exception(()),
}
}
+
+fn lui(core: &mut Core, instr: Instruction) -> InstructionResult {
+ core.reg_write(instr.rd(), instr.imm_u());
+ core.pc = core.pc.wrapping_add(4);
+ InstructionResult::Normal
+}