[Mlir-commits] [mlir] [mlir] Avoid removing returns for mismatch call results (PR #207587)

[Darwin Morris]

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@@ -335,14 +335,26 @@ static void processFuncOp(FunctionOpInterface funcOp, Operation *module,
   // can make our optimization strong by even removing a live return value (%0),
   // since it forwards only to non-live value(s) (%1#1).
   size_t numReturns = funcOp.getNumResults();
+  bool canCleanReturnValues = true;
   BitVector nonLiveRets(numReturns, true);
+
   for (SymbolTable::SymbolUse use : uses) {
     Operation *callOp = use.getUser();
     assert(isa<CallOpInterface>(callOp) && "expected a call-like user");
+
+    if (callOp->getNumResults() != numReturns) {
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darwinmorris wrote:

Good point. I looked through `CallOpInterface` and didn’t find anything that guarantees a 1:1 correspondence between callee results and operation results. I’ll look into adding an explicit interface method for result correspondence (with a conservative default), and then use that in `RemoveDeadValues`, if that seems like the right direction.

https://github.com/llvm/llvm-project/pull/207587