[mlir][transforms] Use isExternal instead of isDeclaration for FunctionOpInterface

[CoTinker]

This PR fixes a bug in RemoveDeadValues where the FunctionOpInterface does not have the isDeclaration method. As a result, we should use the isExternal method instead. Fixes #116347.

[llvmbot]

@llvm/pr-subscribers-mlir

@llvm/pr-subscribers-mlir-core

Author: Longsheng Mou (CoTinker)

Changes

This PR fixes a bug in RemoveDeadValues where the FunctionOpInterface does not have the isDeclaration method. As a result, we should use the isExternal method instead. Fixes #116347.

---

Full diff: https://github.com/llvm/llvm-project/pull/116573.diff

2 Files Affected:

• (modified) mlir/lib/Transforms/RemoveDeadValues.cpp (+2-2)
• (modified) mlir/test/Transforms/remove-dead-values.mlir (+5)

diff --git a/mlir/lib/Transforms/RemoveDeadValues.cpp b/mlir/lib/Transforms/RemoveDeadValues.cpp
index 7e45f18b660ba7..9f942485711297 100644
--- a/mlir/lib/Transforms/RemoveDeadValues.cpp
+++ b/mlir/lib/Transforms/RemoveDeadValues.cpp
@@ -191,10 +191,10 @@ static void cleanSimpleOp(Operation *op, RunLivenessAnalysis &la) {
 ///   non-live across all callers),
 ///   (5) Dropping the uses of these return values from its callers, AND
 ///   (6) Erasing these return values
-/// iff it is not public or declaration.
+/// iff it is not public or external.
 static void cleanFuncOp(FunctionOpInterface funcOp, Operation *module,
                         RunLivenessAnalysis &la) {
-  if (funcOp.isPublic() || funcOp.isDeclaration())
+  if (funcOp.isPublic() || funcOp.isExternal())
     return;
 
   // Get the list of unnecessary (non-live) arguments in `nonLiveArgs`.
diff --git a/mlir/test/Transforms/remove-dead-values.mlir b/mlir/test/Transforms/remove-dead-values.mlir
index 9f2be3331b6b4b..edb100acf3849b 100644
--- a/mlir/test/Transforms/remove-dead-values.mlir
+++ b/mlir/test/Transforms/remove-dead-values.mlir
@@ -374,3 +374,8 @@ func.func @kernel(%arg0: memref<18xf32>) {
 
 // CHECK: func.func private @no_block_func_declaration()
 func.func private @no_block_func_declaration() -> ()
+
+// -----
+
+// CHECK: llvm.func @no_block_external_func()
+llvm.func @no_block_external_func() attributes {sym_visibility = "private"}

[CoTinker]

Ping～

[CoTinker]

ping～

[hstk30-hw]

LGTM