[Mlir-commits] [mlir] [mlir][AsmParser] Fix parseOptionalAttribute consuming loc() as an attribute (PR #180668)

[Mehdi Amini]

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@@ -0,0 +1,32 @@
+// RUN: mlir-opt %s | mlir-opt | FileCheck %s
+
+// Verify that nvvm.barrier roundtrips correctly when loc() annotations use
+// forward-referencing #loc aliases (defined after the module body).
+// This is a regression test for a bug where parseOptionalAttribute would
+// speculatively consume loc(#locN) as an attribute, failing on forward
+// references instead of leaving it for the trailing location parser.
+
+// CHECK-LABEL: @barrier_loc_forward_ref
+module {
+  llvm.func @barrier_loc_forward_ref(%barId : i32, %numThreads : i32, %pred : i32) {
+    // CHECK: nvvm.barrier
+    nvvm.barrier loc(#loc1)
+
+    // CHECK: nvvm.barrier id = %{{.*}}
+    nvvm.barrier id = %barId loc(#loc2)
+
+    // CHECK: nvvm.barrier id = %{{.*}} number_of_threads = %{{.*}}
+    nvvm.barrier id = %barId number_of_threads = %numThreads loc(#loc1)
+
+    // CHECK: %{{.*}} = nvvm.barrier #nvvm.reduction<and> %{{.*}} -> i32
+    %0 = nvvm.barrier #nvvm.reduction<and> %pred -> i32 loc(#loc2)
+
+    // CHECK: %{{.*}} = nvvm.barrier #nvvm.reduction<popc> %{{.*}} -> i32
+    %1 = nvvm.barrier #nvvm.reduction<popc> %pred -> i32 loc(#loc1)
+
+    llvm.return
+  } loc(#loc0)
+} loc(#loc0)
+#loc0 = loc(unknown)
+#loc1 = loc("barrier_test"(#loc0))
+#loc2 = loc("barrier_with_id"(#loc0))
----------------
joker-eph wrote:

Is it possible to have this test written using the test dialect instead?



https://github.com/llvm/llvm-project/pull/180668