1 files changed, 123 insertions, 1 deletions
diff --git a/test/passes/optimize-instructions.wast b/test/passes/optimize-instructions.wast
index 8ef6f67a5..eccbf1268 100644
--- a/test/passes/optimize-instructions.wast
+++ b/test/passes/optimize-instructions.wast
@@ -491,7 +491,19 @@
           )
           (i32.const 24)
         )
-        (i32.const 32767) ;; non-zero and bigger than the mask
+        (i32.const 32767) ;; non-zero and bigger than the mask, with sign bit
+      )
+    )
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $0)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const -149) ;; non-zero and bigger than the mask, without sign bit
       )
     )
     ;; eq of two sign-ext, can both be a zext
@@ -1370,6 +1382,30 @@
           )
           (i32.const 24)
         )
+        (i32.const 64872) ;; no sign bit
+      )
+    )
+    (drop
+      (i32.ne
+        (i32.shr_s
+          (i32.shl
+            (get_local $0)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const -149) ;; no sign bit, not all ones
+      )
+    )
+    (drop
+      (i32.ne
+        (i32.shr_s
+          (i32.shl
+            (get_local $0)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
         (i32.const 111)
       )
     )
@@ -2181,4 +2217,90 @@
       )
     )
   )
+  (func $fuzz-comp-impossible (param $x i32)
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $x)
+            (i32.const 16)
+          )
+          (i32.const 16)
+        )
+        (i32.const 65535) ;; impossible to be equal, the effective sign bit is set, but not the higher bits, which the sign-ext will set on the non-const value
+      )
+    )
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $x)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const 255)
+      )
+    )
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $x)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const 127) ;; safe
+      )
+    )
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $x)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const 128) ;; unsafe again
+      )
+    )
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $x)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const 4223) ;; more big bits, so sign bit though
+      )
+    )
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $x)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const 4224) ;; more big bits
+      )
+    )
+    (drop
+      (i32.eq
+        (i32.shr_s
+          (i32.shl
+            (get_local $x)
+            (i32.const 24)
+          )
+          (i32.const 24)
+        )
+        (i32.const -4) ;; safe even with more big bits, as they are all 1s
+      )
+    )
+  )
 )