diff --git a/tests/meson.build b/tests/meson.build
index 8912fbf..dce27e7 100644
--- a/tests/meson.build
+++ b/tests/meson.build
@@ -15,6 +15,7 @@ endif
 
 testcases = [
   ['prefixes', 'prefixes.txt'],
+  ['modrm', 'modrm.txt'],
 
   ['enter', 'decode-enter.sh'],
   ['imul', 'decode-imul.sh'],
diff --git a/tests/modrm.txt b/tests/modrm.txt
new file mode 100644
index 0000000..abafe95
--- /dev/null
+++ b/tests/modrm.txt
@@ -0,0 +1,34 @@
+# reg
+decode 01c0 [ADD reg4:r0 reg4:r0]
+decode 01c1 [ADD reg4:r1 reg4:r0]
+decode 01d0 [ADD reg4:r0 reg4:r2]
+decode 01ff [ADD reg4:r7 reg4:r7]
+decode64 4101d0 [ADD reg4:r8 reg4:r2]
+decode64 4501d0 [ADD reg4:r8 reg4:r10]
+decode64 4501ff [ADD reg4:r15 reg4:r15]
+# [reg]
+decode 0100 [ADD mem4:r0 reg4:r0]
+decode 0108 [ADD mem4:r0 reg4:r1]
+decode 0101 [ADD mem4:r1 reg4:r0]
+decode 0107 [ADD mem4:r7 reg4:r0]
+decode 0138 [ADD mem4:r0 reg4:r7]
+decode 010424 [ADD mem4:r4 reg4:r0]
+decode64 410100 [ADD mem4:r8 reg4:r0]
+decode64 440108 [ADD mem4:r0 reg4:r9]
+decode64 450100 [ADD mem4:r8 reg4:r8]
+decode64 410107 [ADD mem4:r15 reg4:r0]
+decode64 41010424 [ADD mem4:r12 reg4:r0]
+# [disp32]
+decode32 010501000000 [ADD mem4:0x1 reg4:r0]
+decode32 0105ffffffff [ADD mem4:-0x1 reg4:r0]
+decode 01042501000000 [ADD mem4:0x1 reg4:r0]
+decode64 4101042501000000 [ADD mem4:0x1 reg4:r0]
+# [rip+disp32]
+decode64 010501000000 [ADD mem4:r16+0x1 reg4:r0]
+decode64 41010501000000 [ADD mem4:r16+0x1 reg4:r0]
+# [reg+disp32]
+decode 018001000000 [ADD mem4:r0+0x1 reg4:r0]
+# [reg+eiz+disp32]
+decode 01842501000000 [ADD mem4:r5+0x1 reg4:r0]
+# [reg+s*reg+disp32]
+decode64 4201842501000000 [ADD mem4:r5+1*r12+0x1 reg4:r0]
diff --git a/tests/test.py b/tests/test.py
index 771268e..f2226ce 100644
--- a/tests/test.py
+++ b/tests/test.py
@@ -41,7 +41,8 @@ if __name__ == "__main__":
     test_modes = frozenset(args.test_modes if args.test_modes else [32, 64])
 
     for file in args.cases:
-        cases = [tuple(ln.strip().split(maxsplit=2)) for ln in file.readlines()]
+        cases = [tuple(ln.strip().split(maxsplit=2)) for ln in file.readlines()
+                 if ln and ln[0] != "#"]
         for op, code, expected in cases:
             case_modes = {"decode":{32,64},"decode32":{32},"decode64":{64}}[op]
             if not case_modes & test_modes: continue