[MLIR][test] Check for ml_dtypes before running tests

Author: kwk

mlir/test/python/execution_engine.py

@@ -5,7 +5,12 @@
 from mlir.passmanager import *
 from mlir.execution_engine import *
 from mlir.runtime import *
-from ml_dtypes import bfloat16, float8_e5m2
+try:
+    from ml_dtypes import bfloat16, float8_e5m2
+    HAS_ML_DTYPES=True
+except ModuleNotFoundError:
+    HAS_ML_DTYPES=False
+
 
 MLIR_RUNNER_UTILS = os.getenv(
     "MLIR_RUNNER_UTILS", "../../../../lib/libmlir_runner_utils.so"
@@ -564,7 +569,8 @@ def testBF16Memref():
         log(npout)
 
 
-run(testBF16Memref)
+if HAS_ML_DTYPES:
+    run(testBF16Memref)
 
 
 # Test f8E5M2 memrefs
@@ -603,7 +609,8 @@ def testF8E5M2Memref():
         log(npout)
 
 
-run(testF8E5M2Memref)
+if HAS_ML_DTYPES:
+    run(testF8E5M2Memref)
 
 
 #  Test addition of two 2d_memref