vnf: display also the break mark on report()

When reporting the final instruction, if that was actually a brk (and
hence we stopped because of it), show the breaking mark as that could be
relevant when debugging.

Signed-off-by: Miquel Sabaté Solà <mssola@mssola.com>

4 files changed, 46 insertions, 1 deletions

diff --git a/lib/vnf/src/lib.rs b/lib/vnf/src/lib.rs
index c9ae1a0..534fc1c 100644
--- a/lib/vnf/src/lib.rs
+++ b/lib/vnf/src/lib.rs
@@ -577,7 +577,15 @@ impl Machine {
         }
 
         if !self.active {
-            println!("<end>");
+            if matches!(
+                self.current_instruction.identifier,
+                InstructionIdentifier::Brk
+            ) && let Some(brk) = self.status_register.break_mark
+            {
+                println!("<end> (break mark = ${:02X})", brk);
+            } else {
+                println!("<end>");
+            }
         }
     }
 
diff --git a/scripts/test-e2e.sh b/scripts/test-e2e.sh
index 2dce6fb..4df7128 100755
--- a/scripts/test-e2e.sh
+++ b/scripts/test-e2e.sh
@@ -288,6 +288,12 @@ echo "test: runrom => stack.nes"
 diff tests/out/stack.txt tests/expected/runrom/stack.txt
 exit_code=$((exit_code + $?))
 
+echo "test: runrom => halt.nes"
+./target/debug/nasm -Werror -o tests/out/halt.nes tests/runrom/halt.s
+./target/debug/runrom --dump-memory tests/out/halt.nes > tests/out/halt.txt
+diff tests/out/halt.txt tests/expected/runrom/halt.txt
+exit_code=$((exit_code + $?))
+
 echo "test: runrom => cmp.nes"
 ./target/debug/nasm -Werror --asan -o tests/out/cmp.nes tests/runrom/cmp.s
 ./target/debug/runrom --function --dump-memory tests/out/cmp.nes > tests/out/cmp.txt
diff --git a/tests/expected/runrom/halt.txt b/tests/expected/runrom/halt.txt
new file mode 100644
index 0000000..8e4d83e
--- /dev/null
+++ b/tests/expected/runrom/halt.txt
@@ -0,0 +1,11 @@
+<start>		PC: $8000, cycles: 7, registers: [a: $00, x: $00, y: $00, sp: $FD], status: ----I--
+		[STACK]: 02 80 00 00 
+		[STACK]: 34 02 80 00 00 
+brk		PC: $8000, cycles: 14, registers: [a: $00, x: $00, y: $00, sp: $FA], status: --B-I--
+<end> (break mark = $42)
+
+== Memory dump ==
+
+[$2FB] = $34 [reads=0, writes=1]
+[$2FC] = $02 [reads=0, writes=1]
+[$2FD] = $80 [reads=0, writes=1]
diff --git a/tests/runrom/halt.s b/tests/runrom/halt.s
new file mode 100644
index 0000000..06d0bef
--- /dev/null
+++ b/tests/runrom/halt.s
@@ -0,0 +1,20 @@
+.segment "HEADER"
+    .byte 'N', 'E', 'S', $1A
+    .byte $02, $01
+    .byte $00
+    .byte $00
+
+.segment "CHARS"
+.byte 0
+
+.segment "VECTORS"
+    .addr reset, reset, reset
+
+.segment "CODE"
+;; asan:stack full
+
+.proc reset
+    brk
+    .byte $42
+    rts
+.endproc