From 47cabad5ec1ec2a5f70fa146edf9c3689a615cb6 Mon Sep 17 00:00:00 2001
From: Steven Hugg <hugg@fasterlight.com>
Date: Fri, 7 Jul 2023 23:59:44 -0500
Subject: [PATCH] atari8: debug tree display list

---
 src/machine/atari8.ts      | 45 +++++++++++++++++++++++++++++++++++++-
 src/machine/chips/antic.ts |  8 +++++--
 src/platform/atari8.ts     |  5 +++++
 3 files changed, 55 insertions(+), 3 deletions(-)

diff --git a/src/machine/atari8.ts b/src/machine/atari8.ts
index 827fbb83..9b880c2a 100644
--- a/src/machine/atari8.ts
+++ b/src/machine/atari8.ts
@@ -5,7 +5,7 @@ import { AcceptsKeyInput, AcceptsPaddleInput, AcceptsROM, BasicScanlineMachine,
 import { KeyFlags, Keys, makeKeycodeMap, newAddressDecoder, newKeyboardHandler } from "../common/emu";
 import { hex } from "../common/util";
 import { BaseWASIMachine } from "../common/wasmplatform";
-import { ANTIC, MODE_SHIFT } from "./chips/antic";
+import { ANTIC, MODE_LINES, MODE_SHIFT } from "./chips/antic";
 import { CONSOL, GTIA, TRIG0 } from "./chips/gtia";
 import { POKEY } from "./chips/pokey";
 
@@ -410,6 +410,49 @@ export class Atari800 extends BasicScanlineMachine implements AcceptsPaddleInput
     this.irq_pokey.pot_inputs[controller] = 255 - value;
   }
 
+  getDebugDisplayList() {
+    let pc = this.antic.getDlistAddr();
+    const nextInsn = () => {
+      let b = this.read(pc);
+      pc = ((pc + 1) & 0x3ff) | (pc & ~0x3ff);
+      return b;
+    }
+    let dlist = {};
+    let y = 0;
+    for (let i=0; i<256 && y<240; i++) {
+      let pc0 = pc;
+      let op = nextInsn(); // get mode
+      let mode = op & 0xf;
+      let debugmsg = ""; // op=" + hex(op);
+      let jmp = false;
+      let lines;
+      if (mode == 0) {
+        lines = (((op >> 4) & 7) + 1);
+        debugmsg += " blank=" + lines;
+      } else {
+        lines = MODE_LINES[mode];
+        debugmsg += " mode=" + hex(mode);
+        debugmsg += " lines=" + lines;
+        jmp = (op & ~0x40) == 0x01; // JMP insn?
+        let lms = (op & 0x40) != 0 && (op & 0xf) != 0; // LMS insn?
+        if (jmp && (op & 0x40)) { debugmsg += " JVB"; }
+        else if (jmp) debugmsg += " JMP";
+        else if (lms) debugmsg += " LMS";
+        if (this.antic.isPlayfieldDMAEnabled() && (jmp || lms)) {
+          let dlarg_lo = nextInsn();
+          let dlarg_hi = nextInsn();
+          debugmsg += " $" + hex(dlarg_hi) + "" + hex(dlarg_lo);
+        }
+        if (op & 0x10) { debugmsg += " HSCROL"; }
+        if (op & 0x20) { debugmsg += " VSCROL"; }
+      }
+      dlist["$"+hex(pc0) + " y=" + y] = debugmsg;
+      if (jmp) break;
+      y += lines;
+    }
+    return dlist;
+  }
+
 }
 
 export class Atari5200 extends Atari800 {
diff --git a/src/machine/chips/antic.ts b/src/machine/chips/antic.ts
index 554fff79..ba677d4c 100644
--- a/src/machine/chips/antic.ts
+++ b/src/machine/chips/antic.ts
@@ -42,7 +42,7 @@ const ANTIC_LEFT = 17 - 4; // gtia 34, 4 cycle delay
 const ANTIC_RIGHT = 110 - 4; // gtia 221, 4 cycle delay
 const LAST_DMA_H = 105; // last DMA cycle
 
-const MODE_LINES = [0, 0, 8, 10, 8, 16, 8, 16, 8, 4, 4, 2, 1, 2, 1, 1];
+export const MODE_LINES = [0, 0, 8, 10, 8, 16, 8, 16, 8, 4, 4, 2, 1, 2, 1, 1];
 // how many bits before DMA clock repeats?
 const MODE_PERIOD = [0, 0, 2, 2, 2, 2, 4, 4, 8, 4, 4, 4, 4, 2, 2, 2];
 const MODE_YPERIOD = [0, 0, 0, 0, 0, 1, 0, 1, 0, 0, 2, 1, 0, 0, 0, 0];
@@ -199,8 +199,12 @@ export class ANTIC {
         }
     }
 
+    getDlistAddr() {
+        return this.regs[DLISTL] + (this.regs[DLISTH] << 8);
+    }
+
     nextInsn(): number {
-        let pc = this.regs[DLISTL] + (this.regs[DLISTH] << 8);
+        let pc = this.getDlistAddr();
         let b = this.read(pc);
         //console.log('nextInsn', hex(pc), hex(b), this.v);
         pc = ((pc + 1) & 0x3ff) | (pc & ~0x3ff);
diff --git a/src/platform/atari8.ts b/src/platform/atari8.ts
index a6b9511b..3810f5e5 100644
--- a/src/platform/atari8.ts
+++ b/src/platform/atari8.ts
@@ -63,6 +63,11 @@ class Atari800Platform extends Base6502MachinePlatform<Atari800> {
       return new Uint8Array(biosBinary);
     } else throw new Error('could not load BIOS file');
   }
+  getDebugTree() {
+    let tree = super.getDebugTree();
+    tree['display_list'] = this.machine.getDebugDisplayList();
+    return tree;
+  }
 }
 
 class Atari5200Platform extends Atari800Platform {