[PATCH] D53181: SelectionDAG: Reuse bigger sized constants in memset expansion.

[Matthias Braun via Phabricator via llvm-commits]

MatzeB added inline comments.


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Comment at: test/CodeGen/X86/pr38771.ll:8
 ; CHECK-NEXT:    movl $0, (%rax)
+; CHECK-NEXT:    movq $0, (%rax)
 ; CHECK-NEXT:    retq
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This code changes because ConstantHoisting touches the constants here, and the less aggressive behavior of trunc(OpaqueConstant)" somehow makes DAGCombiner realizes this whole expression being 0 now which it didn't do before. The testcase unfortunately doesn't have enough information to figure out how an equivalent tests would look like that wouldn't constant fold to zero. So this probably has to stay like this...


Repository:
  rL LLVM

https://reviews.llvm.org/D53181