[flang-commits] [flang] [mlir] [mlir][flang] Added Weighted[Region]BranchOpInterface's. (PR #142079)

[Slava Zakharin via flang-commits]

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@@ -375,6 +375,114 @@ def SelectLikeOpInterface : OpInterface<"SelectLikeOpInterface"> {
   ];
 }
 
+//===----------------------------------------------------------------------===//
+// WeightedBranchOpInterface
+//===----------------------------------------------------------------------===//
+
+def WeightedBranchOpInterface : OpInterface<"WeightedBranchOpInterface"> {
+  let description = [{
+    This interface provides weight information for branching terminator
+    operations, i.e. terminator operations with successors.
+
+    This interface provides methods for getting/setting integer non-negative
+    weight of each branch. The probability of executing a branch
+    is computed as the ratio between the branch's weight and the total
+    sum of the weights.
+    The number of weights must match the number of successors of the operation,
+    with one exception for CallOpInterface operations, which may only
----------------
vzakhari wrote:

I believe this is exploited by LLVM dialect tests. Since I replaced the LLVM interface with this one, we have to support this case, e.g. coming from importing LLVM IR.

I can probably do not import the weight from such LLVM IR, and remove this relaxation of the constraint.  This seems to affect the current way LLVM IR/Dialect work, so would that be okay to change that in a follow-up PR?

https://github.com/llvm/llvm-project/pull/142079