[python] Fix loc_tracebacks()

[jmolloy]

There were two bugs lurking in mlir.ir.loc_tracebacks():

1. The default None parameter was not handled correctly (passed to a
   C++ function that expects ints.
2. The yield was incorrectly indented meaning loc_tracebacks()
   could not be nested (a "generator didn't yield" exception would be
   raised).

Added testing of loc_tracebacks by replacing the custom contextmanager
in the auto_location.py test with the loc_tracebacks() API.

Had to harden the test to line number differences.

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[llvmbot]

@llvm/pr-subscribers-mlir

Author: James Molloy (jmolloy)

Changes

There were two bugs lurking in mlir.ir.loc_tracebacks():

1. The default None parameter was not handled correctly (passed to a
   C++ function that expects ints.
2. The yield was incorrectly indented meaning loc_tracebacks()
   could not be nested (a "generator didn't yield" exception would be
   raised).

Added testing of loc_tracebacks by replacing the custom contextmanager
in the auto_location.py test with the loc_tracebacks() API.

Had to harden the test to line number differences.

---

Full diff: https://github.com/llvm/llvm-project/pull/170831.diff

2 Files Affected:

• (modified) mlir/python/mlir/ir.py (+2-1)
• (modified) mlir/test/python/ir/auto_location.py (+14-18)

diff --git a/mlir/python/mlir/ir.py b/mlir/python/mlir/ir.py
index 11477d061e897..f4aa2d6b051c8 100644
--- a/mlir/python/mlir/ir.py
+++ b/mlir/python/mlir/ir.py
@@ -34,11 +34,12 @@ def loc_tracebacks(*, max_depth: int | None = None) -> Iterable[None]:
     """
     old_enabled = _globals.loc_tracebacks_enabled()
     old_limit = _globals.loc_tracebacks_frame_limit()
+    max_depth = old_limit if max_depth is None else max_depth
     try:
         _globals.set_loc_tracebacks_frame_limit(max_depth)
         if not old_enabled:
             _globals.set_loc_tracebacks_enabled(True)
-            yield
+        yield
     finally:
         if not old_enabled:
             _globals.set_loc_tracebacks_enabled(False)
diff --git a/mlir/test/python/ir/auto_location.py b/mlir/test/python/ir/auto_location.py
index 83168901341a8..b85beeec7f617 100644
--- a/mlir/test/python/ir/auto_location.py
+++ b/mlir/test/python/ir/auto_location.py
@@ -15,17 +15,10 @@ def run(f):
     assert Context._get_live_count() == 0
 
 
-@contextmanager
-def with_infer_location():
-    _cext.globals.set_loc_tracebacks_enabled(True)
-    yield
-    _cext.globals.set_loc_tracebacks_enabled(False)
-
-
 # CHECK-LABEL: TEST: testInferLocations
 @run
 def testInferLocations():
-    with Context() as ctx, with_infer_location():
+    with Context() as ctx, loc_tracebacks():
         ctx.allow_unregistered_dialects = True
 
         op = Operation.create("custom.op1")
@@ -34,24 +27,27 @@ def testInferLocations():
         two = arith.constant(IndexType.get(), 2)
 
         # fmt: off
-        # CHECK: loc(callsite("testInferLocations"("{{.*}}[[SEP:[/\\]+]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":31:13 to :43) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":13:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":26:1 to :4))))
+        # CHECK: loc(callsite("testInferLocations"("{{.*}}[[SEP:[/\\]+]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:13 to :43) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":13:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:1 to :4))))
         # fmt: on
         print(op.location)
 
-        # fmt: off
-        # CHECK: loc(callsite("ConstantOp.__init__"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]arith.py":65:12 to :76) at callsite("constant"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]arith.py":110:40 to :81) at callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":32:14 to :48) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":13:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":26:1 to :4))))))
-        # fmt: on
-        print(one.location)
+        # Test nesting of loc_tracebacks().
+        with loc_tracebacks():
+        
+            # fmt: off
+            # CHECK: loc(callsite("ConstantOp.__init__"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]arith.py":65:12 to :76) at callsite("constant"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]arith.py":110:40 to :81) at callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:14 to :48) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:1 to :4))))))
+            # fmt: on
+            print(one.location)
 
         # fmt: off
-        # CHECK: loc(callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":34:14 to :48) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":13:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":26:1 to :4))))
+        # CHECK: loc(callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:14 to :48) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:1 to :4))))
         # fmt: on
         print(two.location)
 
         _cext.globals.register_traceback_file_inclusion(_arith_ops_gen.__file__)
         three = arith.constant(IndexType.get(), 3)
         # fmt: off
-        # CHECK: loc(callsite("ConstantOp.__init__"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]_arith_ops_gen.py":{{[0-9]+}}:4 to :235) at callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":52:16 to :50) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":13:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":26:1 to :4)))))
+        # CHECK: loc(callsite("ConstantOp.__init__"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]_arith_ops_gen.py":{{[0-9]+}}:4 to :235) at callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:16 to :50) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:1 to :4)))))
         # fmt: on
         print(three.location)
 
@@ -60,7 +56,7 @@ def foo():
             print(four.location)
 
         # fmt: off
-        # CHECK: loc(callsite("ConstantOp.__init__"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]_arith_ops_gen.py":{{[0-9]+}}:4 to :235) at callsite("testInferLocations.<locals>.foo"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":59:19 to :53) at callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":65:8 to :13) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":13:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":26:1 to :4))))))
+        # CHECK: loc(callsite("ConstantOp.__init__"("{{.*}}[[SEP]]mlir[[SEP]]dialects[[SEP]]_arith_ops_gen.py":{{[0-9]+}}:4 to :235) at callsite("testInferLocations.<locals>.foo"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:19 to :53) at callsite("testInferLocations"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:8 to :13) at callsite("run"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:4 to :7) at "<module>"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:1 to :4))))))
         # fmt: on
         foo()
 
@@ -86,13 +82,13 @@ def bar3():
 
         _cext.globals.set_loc_tracebacks_frame_limit(2)
         # fmt: off
-        # CHECK: loc(callsite("testInferLocations.<locals>.bar1.<locals>.bar2.<locals>.bar3"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":77:27 to :61) at "testInferLocations.<locals>.bar1.<locals>.bar2"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":80:16 to :22)))
+        # CHECK: loc(callsite("testInferLocations.<locals>.bar1.<locals>.bar2.<locals>.bar3"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:27 to :61) at "testInferLocations.<locals>.bar1.<locals>.bar2"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:16 to :22)))
         # fmt: on
         bar1()
 
         _cext.globals.set_loc_tracebacks_frame_limit(1)
         # fmt: off
-        # CHECK: loc("testInferLocations.<locals>.bar1.<locals>.bar2.<locals>.bar3"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":77:27 to :61))
+        # CHECK: loc("testInferLocations.<locals>.bar1.<locals>.bar2.<locals>.bar3"("{{.*}}[[SEP]]test[[SEP]]python[[SEP]]ir[[SEP]]auto_location.py":{{[0-9]+}}:27 to :61))
         # fmt: on
         bar1()
 

[github-actions]

✅ With the latest revision this PR passed the Python code formatter.

[github-actions]

@jmolloy Congratulations on having your first Pull Request (PR) merged into the LLVM Project!

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