From e7dc2ce750df1c33ce97ce0a4052ab0aa55dd189 Mon Sep 17 00:00:00 2001
From: Steven Hugg <hugg@fasterlight.com>
Date: Tue, 15 Jun 2021 09:26:22 -0500
Subject: [PATCH] arm: fixed pc and listing for thumb

---
 src/common/cpu/ARM.ts    |  5 +++--
 src/worker/workermain.ts | 10 ++++++++--
 2 files changed, 11 insertions(+), 4 deletions(-)

diff --git a/src/common/cpu/ARM.ts b/src/common/cpu/ARM.ts
index 8e7b92e9..13799a60 100644
--- a/src/common/cpu/ARM.ts
+++ b/src/common/cpu/ARM.ts
@@ -2749,7 +2749,7 @@ ARMCore.prototype.resetCPU = function(startOffset) {
 
 ARMCore.prototype.freeze = function() : ARMCoreState {
 	return {
-		PC: this.gprs[15] - 4,
+		PC: this.gprs[15] - this.instructionWidth,
 		SP: this.gprs[13],
 		'gprs': [
 			this.gprs[0],
@@ -4097,6 +4097,7 @@ ARMCore.prototype.compileThumb = function(instruction) {
 
 	op.execMode = ARMMode.MODE_THUMB;
 	op.fixedJump = op.fixedJump || false;
+	//console.log(hex(instruction), op);
 	return op;
 };
 
@@ -4137,7 +4138,7 @@ export class ARM32CPU implements CPU, InstructionBased, ARMMMUInterface, ARMIRQI
 		return n > 0 ? n : 1;
 	}
 	getPC(): number {
-		return this.core.gprs[15] - 4;
+		return this.core.gprs[15] - this.core.instructionWidth;
 	}
 	getSP(): number {
 		return this.core.gprs[13];
diff --git a/src/worker/workermain.ts b/src/worker/workermain.ts
index ad054812..1c0eea0e 100644
--- a/src/worker/workermain.ts
+++ b/src/worker/workermain.ts
@@ -2935,8 +2935,14 @@ function assembleARMIPS(step:BuildStep) {
         var lst = listings[path2];
         if (lst == null) { lst = listings[path2] = {lines:[]}; }
         var ofs = parseInt(m[1], 16);
-        var insn = objout.slice(ofs, ofs+4); // TODO: doesn't do thumb or !=4 bytes
-        if (lastofs == ofs) lst.lines.pop(); else lastofs = ofs;
+        var insn = objout.slice(ofs, ofs+4);
+        if (lastofs == ofs) {
+            lst.lines.pop(); // get rid of duplicate offset
+        } else if (lastofs+2 == ofs) {
+          var lastline = lst.lines[lst.lines.length-1]; // convert 4-byte to 2-byte insn
+          if (lastline && lastline.insns) lastline.insns = lastline.insns.substring(4,8);
+        }
+        lastofs = ofs;
         lst.lines.push({
           path: path,
           line: parseInt(m[4]),