[PATCH] D47725: [SelectionDAG] Provide default expansion for rotates

Eli Friedman via Phabricator via llvm-commits llvm-commits at lists.llvm.org
Wed Jun 6 15:09:27 PDT 2018


efriedma added inline comments.


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Comment at: test/CodeGen/Hexagon/rotate.ll:107
+; CHECK: r[[R74:[0-9]+]]:[[R75:[0-9]+]] = asl(r1:0,r[[R71]])
+; CHECK: r[[R74]]:[[R75]] |= lsr(r1:0,r[[R73]])
+define i64 @f7(i64 %a0, i32 %a1) #0 {
----------------
This looks correct, but low quality.  Trunk generates 3 instructions, the ideal rotate expansion would generate 5 instructions (I think), this is 6 instructions.


Repository:
  rL LLVM

https://reviews.llvm.org/D47725





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