[Mlir-commits] [mlir] [mlir][python][nfc] Test `-print-ir-after-all` (PR #75742)

[Maksim Levental]

================
@@ -281,3 +281,26 @@ def testPostPassOpInvalidation():
         # CHECK:   return
         # CHECK: }
         log(module)
+
+
+# Test -print-ir-after-all.
+# CHECK-LABEL: TEST: testPrintIrAfterAll
+ at run
+def testPrintIrAfterAll():
+    with Context() as ctx:
+        module = ModuleOp.parse(
+            """
+          module {
+            func.func @main() {
+              %0 = arith.constant 10
+              return
+            }
+          }
+        """
+        )
+        pm = PassManager.parse("builtin.module(canonicalize)")
+        ctx.enable_multithreading(False)
+        pm.enable_ir_printing()
+        pm.run(module)
+        log(module)
----------------
makslevental wrote:

```suggestion
        # CHECK: // -----// IR Dump Before Canonicalizer (canonicalize) ('builtin.module' operation) //----- //
        # CHECK: module {
        # CHECK:   func.func @main() {
        # CHECK:     %[[C10:.*]] = arith.constant 10 : i64
        # CHECK:     return
        # CHECK:   }
        # CHECK: }
        # CHECK: 
        # CHECK: 
        # CHECK: // -----// IR Dump After Canonicalizer (canonicalize) ('builtin.module' operation) //----- //
        # CHECK: module {
        # CHECK:   func.func @main() {
        # CHECK:     return
        # CHECK:   }
        # CHECK: }
        pm.run(module)
```

Would definitely prefer this for an explicit illustration.

https://github.com/llvm/llvm-project/pull/75742