From 030ca2281206d0b8d48d3e590becd3932ef9051f Mon Sep 17 00:00:00 2001
From: pjht <pterpstra@pterpstra.com>
Date: Thu, 7 Dec 2023 13:56:41 -0600
Subject: [PATCH] Allow dissasembly errors to include abnormal traps

---
 src/m68k.rs | 26 +++++++++++++++++++-------
 src/main.rs |  3 ++-
 2 files changed, 21 insertions(+), 8 deletions(-)

diff --git a/src/m68k.rs b/src/m68k.rs
index adbdd1d..8649612 100644
--- a/src/m68k.rs
+++ b/src/m68k.rs
@@ -144,8 +144,14 @@ impl From<DetailedBusError> for InsExecError {
     }
 }
 
-
-
+impl Display for InsExecError {
+    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
+        match self {
+            InsExecError::BusError(err) => f.write_fmt(format_args!("{}", err)),
+            InsExecError::AbnormalTrap => f.write_str("Abnormal trap"),
+        }
+    }
+}
 
 #[derive(Debug)]
 pub struct M68K {
@@ -243,11 +249,14 @@ impl M68K {
     pub fn disassemble(
         &mut self,
         loc: u32,
-    ) -> Result<(Instruction, u32), DisassemblyError<DetailedBusError>> {
+    ) -> Result<(Instruction, u32), DisassemblyError<InsExecError>> {
         disas::disasm(loc, &mut |addr| {
-            self.read_word(addr).map_err(|err| DetailedBusError {
-                cause: BusErrorCause::ReadingInstruction,
-                ..err.try_into_bus_error().unwrap()
+            self.read_word(addr).map_err(|err| match err {
+                InsExecError::AbnormalTrap => InsExecError::AbnormalTrap,
+                InsExecError::BusError(err) => InsExecError::BusError(DetailedBusError {
+                    cause: BusErrorCause::ReadingInstruction,
+                    ..err
+                }),
             })
         })
     }
@@ -316,7 +325,10 @@ impl M68K {
         }
         let (ins, new_pc) = match self.disassemble(self.pc) {
             Ok(ins) => ins,
-            Err(DisassemblyError::InvalidInstruction) => panic!("Invalid instruction"),
+            Err(DisassemblyError::InvalidInstruction) => {
+                self.trap(4)?;
+                return self.step_ret_berr();
+            }
             Err(DisassemblyError::ReadError(e)) => return Err(e.into()),
         };
         self.pc = new_pc;
diff --git a/src/main.rs b/src/main.rs
index 4960222..06bace2 100644
--- a/src/main.rs
+++ b/src/main.rs
@@ -25,6 +25,7 @@ use clap::Parser;
 use disas::DisassemblyError;
 use indexmap::IndexSet;
 use itertools::Itertools;
+use m68k::InsExecError;
 use parse_int::parse;
 use reedline_repl_rs::{
     clap::{builder::BoolishValueParser, Arg, ArgAction, Command},
@@ -527,7 +528,7 @@ fn disas_fmt(
     cpu: &mut M68K,
     addr: u32,
     symbol_tables: &SymbolTables,
-) -> (String, Result<u32, DisassemblyError<DetailedBusError>>) {
+) -> (String, Result<u32, DisassemblyError<InsExecError>>) {
     let addr_fmt = if let Some((table, symbol, offset)) = symbol_tables.address_to_symbol(addr) {
         format!("{table}:{symbol} + {offset} (0x{addr:x})")
     } else {