From cc0cb584a83a729e52ca0ab7e54beaee34072535 Mon Sep 17 00:00:00 2001
From: Steven Hugg <hugg@fasterlight.com>
Date: Sun, 1 Dec 2019 11:47:42 -0600
Subject: [PATCH] added message when emulation stopped (EmuHalt)

---
 src/common/baseplatform.ts | 9 ++++++---
 src/common/emu.ts          | 2 +-
 src/ide/ui.ts              | 3 ++-
 src/platform/nes.ts        | 2 +-
 4 files changed, 10 insertions(+), 6 deletions(-)

diff --git a/src/common/baseplatform.ts b/src/common/baseplatform.ts
index f676fe6b..87fd7f81 100644
--- a/src/common/baseplatform.ts
+++ b/src/common/baseplatform.ts
@@ -143,7 +143,7 @@ export interface MemoryBus {
 
 export type DebugCondition = () => boolean;
 export type DebugEvalCondition = (c:CpuState) => boolean;
-export type BreakpointCallback = (s:EmuState) => void;
+export type BreakpointCallback = (s:EmuState, msg?:string) => void;
 // for composite breakpoints w/ single debug function
 export class BreakpointList {
   id2bp : {[id:string] : Breakpoint} = {};
@@ -283,16 +283,19 @@ export abstract class BaseDebugPlatform extends BasePlatform {
   wasBreakpointHit() : boolean {
     return this.debugBreakState != null;
   }
-  breakpointHit(targetClock : number) {
+  breakpointHit(targetClock : number, reason? : string) {
     console.log(this.debugTargetClock, targetClock, this.debugClock, this.isStable());
     this.debugTargetClock = targetClock;
     this.debugBreakState = this.saveState();
     console.log("Breakpoint at clk", this.debugClock, "PC", this.debugBreakState.c.PC.toString(16));
     this.pause();
     if (this.onBreakpointHit) {
-      this.onBreakpointHit(this.debugBreakState);
+      this.onBreakpointHit(this.debugBreakState, reason);
     }
   }
+  haltAndCatchFire(reason : string) {
+    this.breakpointHit(this.debugClock, reason);
+  }
   runEval(evalfunc : DebugEvalCondition) {
     this.setDebugCondition( () => {
       if (++this.debugClock >= this.debugTargetClock && this.isStable()) {
diff --git a/src/common/emu.ts b/src/common/emu.ts
index e1fb962d..69711583 100644
--- a/src/common/emu.ts
+++ b/src/common/emu.ts
@@ -251,7 +251,7 @@ export class AnimationTimer {
       } catch (e) {
         this.running = false;
         this.pulsing = false;
-        throw e; // TODO: throw EmuHalt hides stack trace
+        throw e;
       }
     }
     if (this.useReqAnimFrame)
diff --git a/src/ide/ui.ts b/src/ide/ui.ts
index 8b7d0a15..252631a5 100644
--- a/src/ide/ui.ts
+++ b/src/ide/ui.ts
@@ -1123,9 +1123,10 @@ function uiDebugCallback(state: EmuState) {
 }
 
 function setupDebugCallback(btnid? : string) {
-  if (platform.setupDebug) platform.setupDebug((state:EmuState) => {
+  if (platform.setupDebug) platform.setupDebug((state:EmuState, msg:string) => {
     uiDebugCallback(state);
     setDebugButtonState(btnid||"pause", "stopped");
+    msg && showErrorAlert([{msg:"STOPPED: " + msg, line:0}]);
   });
 }
 
diff --git a/src/platform/nes.ts b/src/platform/nes.ts
index 626eb8d9..d6d17e24 100644
--- a/src/platform/nes.ts
+++ b/src/platform/nes.ts
@@ -131,7 +131,7 @@ class JSNESPlatform extends Base6502Platform implements Platform, Probeable {
     //this.nes.ppu.showSpr0Hit = true;
     //this.nes.ppu.clipToTvSize = false;
     this.nes.stop = () => {
-      this.breakpointHit(this.debugClock);
+      this.haltAndCatchFire("Illegal instruction");
       throw new EmuHalt("CPU STOPPED");
     };
     // insert debug hook