[Mlir-commits] [mlir] [mlir][vector] Refactor WarpOpScfForOp to support unused or swapped forOp results. (PR #147620)

[Charitha Saumya]

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@@ -1769,81 +1772,155 @@ struct WarpOpScfForOp : public WarpDistributionPattern {
               AffineMap map = distributionMapFn(operand->get());
               distType = getDistributedType(vecType, map, warpOp.getWarpSize());
             }
-            inputTypes.push_back(operand->get().getType());
-            distTypes.push_back(distType);
+            escapingValueInputTypes.push_back(operand->get().getType());
+            escapingValuedistTypes.push_back(distType);
           }
         });
 
-    if (llvm::is_contained(distTypes, Type{}))
+    if (llvm::is_contained(escapingValuedistTypes, Type{}))
       return failure();
+    // Warp op can yield two types of values:
+    // 1. Values that are not results of the forOp:
+    //    These values must also be yielded by the new warp op. Also, we need to
+    //    record the index mapping for these values to replace them later.
+    // 2. Values that are results of the forOp:
+    //    In this case, we record the index mapping between the warp op result
+    //    index and matching forOp result index.
+    SmallVector<Value> nonForYieldedValues;
+    SmallVector<unsigned> nonForResultIndices;
+    DenseMap<unsigned, unsigned> forResultMapping;
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charithaintc wrote:

I thought about using IRMapping. but it has the same amount of book keeping. So I don't see any added benefit. DenseMap does the job and code looks easy to read in my view.

But if you can point to some code example with value mapping I will reconsider it. 

https://github.com/llvm/llvm-project/pull/147620