[mlir][mesh] Exit after signalPassFailure to fix a crash

[CoTinker]

Fixes #131435.

[llvmbot]

@llvm/pr-subscribers-mlir

Author: Longsheng Mou (CoTinker)

Changes

Fixes #131435.

---

Full diff: https://github.com/llvm/llvm-project/pull/132662.diff

2 Files Affected:

• (modified) mlir/lib/Dialect/Mesh/Transforms/ShardingPropagation.cpp (+1-1)
• (added) mlir/test/Dialect/Mesh/sharding-propagation-failed.mlir (+4)

diff --git a/mlir/lib/Dialect/Mesh/Transforms/ShardingPropagation.cpp b/mlir/lib/Dialect/Mesh/Transforms/ShardingPropagation.cpp
index 8c989cce63406..4452dd65fce9d 100644
--- a/mlir/lib/Dialect/Mesh/Transforms/ShardingPropagation.cpp
+++ b/mlir/lib/Dialect/Mesh/Transforms/ShardingPropagation.cpp
@@ -369,7 +369,7 @@ struct ShardingPropagation
     OpBuilder builder(ctx);
     if (!region.hasOneBlock()) {
       funcOp.emitOpError() << "only one block is supported!";
-      signalPassFailure();
+      return signalPassFailure();
     }
     Block &block = region.front();
 
diff --git a/mlir/test/Dialect/Mesh/sharding-propagation-failed.mlir b/mlir/test/Dialect/Mesh/sharding-propagation-failed.mlir
new file mode 100644
index 0000000000000..b5eb98d859c36
--- /dev/null
+++ b/mlir/test/Dialect/Mesh/sharding-propagation-failed.mlir
@@ -0,0 +1,4 @@
+// RUN: mlir-opt --pass-pipeline="builtin.module(func.func(sharding-propagation))" %s -verify-diagnostics
+
+// expected-error @+1 {{'func.func' op only one block is supported!}}
+func.func private @no_block_function(i64)

[fschlimb]

LGTM. Thanks!