From 502647806c09d76ab5b03fae3069de49305d61b7 Mon Sep 17 00:00:00 2001
From: Rekai Musuka <rekai@musuka.dev>
Date: Tue, 19 Sep 2023 23:15:04 -0500
Subject: [PATCH] feat(v5te): stub THUMB BKPT

---
 src/arm/cpu/thumb/data_processing.zig | 10 ++++++++++
 src/arm/v5te.zig                      | 19 ++++++++++++-------
 2 files changed, 22 insertions(+), 7 deletions(-)

diff --git a/src/arm/cpu/thumb/data_processing.zig b/src/arm/cpu/thumb/data_processing.zig
index d0e4b63..36bb5ea 100644
--- a/src/arm/cpu/thumb/data_processing.zig
+++ b/src/arm/cpu/thumb/data_processing.zig
@@ -216,3 +216,13 @@ pub fn fmt13(comptime InstrFn: type, comptime S: bool) InstrFn {
         }
     }.inner;
 }
+
+pub fn bkpt(comptime InstrFn: type) InstrFn {
+    const Arm32 = @typeInfo(@typeInfo(@typeInfo(InstrFn).Pointer.child).Fn.params[0].type.?).Pointer.child;
+
+    return struct {
+        fn inner(cpu: *Arm32, _: u16) void {
+            cpu.panic("TODO: handle THUMB BKPT", .{});
+        }
+    }.inner;
+}
diff --git a/src/arm/v5te.zig b/src/arm/v5te.zig
index 69a5bec..0b07b03 100644
--- a/src/arm/v5te.zig
+++ b/src/arm/v5te.zig
@@ -212,13 +212,18 @@ pub const thumb = struct {
                             const rd = i >> 2 & 0x7;
                             break :blk processing.fmt12(InstrFn, isSP, rd);
                         },
-                        0b011 => if (i >> 4 & 1 == 1) blk: {
-                            const L = i >> 5 & 1 == 1;
-                            const R = i >> 2 & 1 == 1;
-                            break :blk block_transfer.fmt14(InstrFn, L, R);
-                        } else blk: {
-                            const S = i >> 1 & 1 == 1;
-                            break :blk processing.fmt13(InstrFn, S);
+                        0b011 => switch (@as(u2, @truncate(i >> 3 & 0x3))) {
+                            0b10 => blk: {
+                                // PUSH / POP
+                                const L = i >> 5 & 1 == 1;
+                                const R = i >> 2 & 1 == 1;
+                                break :blk block_transfer.fmt14(InstrFn, L, R);
+                            },
+                            0b11 => processing.bkpt(InstrFn),
+                            else => blk: {
+                                const S = i >> 1 & 1 == 1;
+                                break :blk processing.fmt13(InstrFn, S);
+                            },
                         },
                         0b100 => blk: {
                             const L = i >> 5 & 1 == 1;