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-rw-r--r--src/instructions/rvi.rs30
1 files changed, 30 insertions, 0 deletions
diff --git a/src/instructions/rvi.rs b/src/instructions/rvi.rs
index 239ae98..f182e88 100644
--- a/src/instructions/rvi.rs
+++ b/src/instructions/rvi.rs
@@ -61,6 +61,26 @@ pub fn sd(core: &mut Core, instr: Instruction) -> InstructionResult {
}
}
+pub fn ld(core: &mut Core, instr: Instruction) -> InstructionResult {
+ let addr = core.reg_read(instr.rs1()).wrapping_add(instr.imm_s());
+
+ if !addr.is_multiple_of(std::mem::size_of::<DWord>() as Addr) {
+ return InstructionResult::Exception(());
+ }
+
+ let page = (addr / 4096) as PageNum;
+ let offset = (addr / 8 & ((4096 / 8 as Addr) - 1)) as u16;
+
+ match core.mem.read_dword(page, offset) {
+ Ok(x) => {
+ core.reg_write(instr.rd(), x);
+ core.advance_pc();
+ InstructionResult::Normal
+ }
+ Err(_) => InstructionResult::Exception(()),
+ }
+}
+
pub fn sb(core: &mut Core, instr: Instruction) -> InstructionResult {
let addr = core.reg_read(instr.rs1()).wrapping_add(instr.imm_s());
@@ -145,6 +165,16 @@ pub fn beq(core: &mut Core, instr: Instruction) -> InstructionResult {
InstructionResult::Normal
}
+pub fn bne(core: &mut Core, instr: Instruction) -> InstructionResult {
+ if core.reg_read(instr.rs1()) != core.reg_read(instr.rs2()) {
+ core.pc = core.pc.wrapping_add(instr.imm_b());
+ } else {
+ core.advance_pc();
+ }
+
+ InstructionResult::Normal
+}
+
pub fn slli(core: &mut Core, instr: Instruction) -> InstructionResult {
core.reg_write(instr.rd(), core.reg_read(instr.rs1()) << instr.imm_shamt());