[PATCH] D91937: [ISel] Port AArch64 SABD and UABD to DAGCombine

[Simon Pilgrim via Phabricator via llvm-commits]

RKSimon added a comment.

Yeah - sum-of-abs-diff is a bit more complex - technically we could use ABD as a stepping stone in pattern matching it



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Comment at: llvm/include/llvm/CodeGen/ISDOpcodes.h:584
+  // two numbers interpreted as signed/unsigned.
+  // i.e trunc(abs(sext(Op0) - sext(Op1))).
+  ABDS,
----------------
Add comments showing both ADDS and ADDU patterns


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Comment at: llvm/lib/CodeGen/SelectionDAG/DAGCombiner.cpp:8851
+// Generates UABD/SABD instruction.
+static SDValue combineAbsToABD(SDNode *N, SelectionDAG &DAG,
+                               const TargetLowering &TLI) {
----------------
naming consistency - combineAbsToAbd or combineABSToABD


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  https://reviews.llvm.org/D91937/new/

https://reviews.llvm.org/D91937