Impl Thumb 18 (Branch)

Former-commit-id: 152dab739a1fa1b9d324084fc810b8540af9c3d7
This commit is contained in:
Michel Heily 2019-07-05 16:21:24 +03:00
parent 74329c2a0b
commit 638e449421
2 changed files with 26 additions and 3 deletions

View file

@ -170,6 +170,17 @@ impl ThumbInstruction {
)
}
fn fmt_thumb_branch(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(
f,
"b\t{addr:#x}",
addr = {
let offset = (self.offset11() << 21) >> 20;
(self.pc as i32 + 4).wrapping_add(offset) as Addr
}
)
}
fn fmt_thumb_branch_long_with_link(&self, f: &mut fmt::Formatter) -> fmt::Result {
write!(f, "bl\t#0x{:08x}", {
let offset11 = self.offset11();
@ -198,6 +209,7 @@ impl fmt::Display for ThumbInstruction {
ThumbFormat::AddSp => self.fmt_thumb_add_sp(f),
ThumbFormat::PushPop => self.fmt_thumb_push_pop(f),
ThumbFormat::BranchConditional => self.fmt_thumb_branch_with_cond(f),
ThumbFormat::Branch => self.fmt_thumb_branch(f),
ThumbFormat::BranchLongWithLink => self.fmt_thumb_branch_long_with_link(f),
_ => write!(f, "({:?})", self),
}

View file

@ -132,11 +132,11 @@ impl Core {
insn.rs()
};
let arm_alu_op: ArmOpCode = insn.format5_op().into();
let op1 = self.gpr[dst_reg] as i32;
let op2 = self.gpr[src_reg] as i32;
let op1 = self.get_reg(dst_reg) as i32;
let op2 = self.get_reg(src_reg) as i32;
let result = self.alu(arm_alu_op, op1, op2, true);
if let Some(result) = result {
self.gpr[dst_reg] = result as u32;
self.set_reg(dst_reg, result as u32);
}
Ok(CpuPipelineAction::IncPC)
}
@ -269,6 +269,16 @@ impl Core {
}
}
fn exec_thumb_branch(
&mut self,
_bus: &mut Bus,
insn: ThumbInstruction,
) -> CpuExecResult {
let offset = ((insn.offset11() << 21) >> 20) as i32;
self.pc = (self.pc as i32).wrapping_add(offset) as u32;
Ok(CpuPipelineAction::Flush)
}
fn exec_thumb_branch_long_with_link(
&mut self,
_bus: &mut Bus,
@ -305,6 +315,7 @@ impl Core {
ThumbFormat::AddSp => self.exec_thumb_add_sp(bus, insn),
ThumbFormat::PushPop => self.exec_thumb_push_pop(bus, insn),
ThumbFormat::BranchConditional => self.exec_thumb_branch_with_cond(bus, insn),
ThumbFormat::Branch => self.exec_thumb_branch(bus, insn),
ThumbFormat::BranchLongWithLink => self.exec_thumb_branch_long_with_link(bus, insn),
_ => unimplemented!("thumb not implemented {:#x?}", insn),
}