Fix some edge case for dbcc found on random tests

2 files changed, 7 insertions, 2 deletions

diff --git a/disasm.cpp b/disasm.cpp
index 2da9835..d4aaa3a 100644
--- a/disasm.cpp
+++ b/disasm.cpp
@@ -728,7 +728,7 @@ static void disasm_dbcc(DisasmNode& node, uint16_t instr, const DataBuffer &code
     const uint32_t branch_addr = static_cast<uint32_t>(node.offset + dispmt_raw);
     node.branch_addr = branch_addr;
     node.has_branch_addr = true;
-    const int16_t dispmt = dispmt_raw + kInstructionSizeStepBytes;
+    const int32_t dispmt = dispmt_raw + kInstructionSizeStepBytes;
     snprintf(node.mnemonic, kMnemonicBufferSize, "%s", mnemonic);
     const char * const sign = dispmt >= 0 ? "+" : "";
     // FIXME support s.rel_marks option for this instruction
diff --git a/test.bash b/test.bash
index 9724d7f..a065465 100644
--- a/test.bash
+++ b/test.bash
@@ -32,7 +32,7 @@ run_test_simple() {
   echo -ne "Test \"${test_name}\"... "
   echo -ne "${data}" >${file_orig_bin}
   ${DISASM} -t ${TRACE_FILE} -o ${file_asm} ${file_orig_bin}
-  ${AS} -o ${file_as_o} ${file_asm}
+  ${AS} -m68000 -o ${file_as_o} ${file_asm}
   ${LD} -o ${file_as_elf} ${file_as_o}
   ${OBJCOPY} ${file_as_elf} -O binary ${file_as_bin}
   if ! cmp ${file_orig_bin} ${file_as_bin} >/dev/null 2>&1; then
@@ -157,6 +157,11 @@ run_test_iterative "seq Xn" "\x57" 0xc0 8 1
 run_test_simple "dbt negative displacement" "\x50\xcf\xff\xfc"
 run_test_simple "dbt positive displacement" "\x50\xcf\x01\x08"
 
+# 50c9 7ffe
+#
+# From random tests
+run_test_simple "dbt %d1,.+32768" "\x50\xc9\x7f\xfe"
+
 # 60xx
 #
 run_test_simple "bras negative displacement" "\x60\xfc"