[Mlir-commits] [mlir] [MLIR][RemoveDeadValues] Mark arguments of a public function Live (PR #162038)

[Mehdi Amini]

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@@ -569,6 +569,24 @@ module @return_void_with_unused_argument {
     call @fn_return_void_with_unused_argument(%arg0, %unused) : (i32, memref<4xi32>) -> ()
     return %unused : memref<4xi32>
   }
+
+  // the function signature is immutable because it is public.
+  func.func public @immutable_fn_with_unused_argument(%arg0: i32, %arg1: memref<4xf32>) -> () {
+    return
+  }
+
+  // CHECK-LABEL: func.func @main2
+  // CHECK: %[[MEM:.*]] = memref.alloc() : memref<4xf32>
+  // CHECK: %[[UNUSED:.*]] = arith.constant 0 : i32
+  // CHECK: call @immutable_fn_with_unused_argument(%[[UNUSED]], %[[MEM]]) : (i32, memref<4xf32>) -> ()
+  func.func @main2() -> () {
+    %one = arith.constant 1 : i32
+    %scalar = arith.addi %one, %one: i32
+    %mem = memref.alloc() : memref<4xf32>
+
+    call @immutable_fn_with_unused_argument(%scalar, %mem) : (i32, memref<4xf32>) -> ()
+    return
+  }
 }
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joker-eph wrote:

Seems reasonable,  but this needs to be callable from RemoveDeadValues itself (the pass can't crash itself here)

https://github.com/llvm/llvm-project/pull/162038