[PATCH] D17221: Don't combine fp_round (fp_round x) if f80 to f16 is generated

[Pirama Arumuga Nainar via llvm-commits]

pirama added inline comments.

================
Comment at: test/CodeGen/X86/half.ll:270
@@ +269,3 @@
+; fp_round and the subsequent fptrunc from float to half.
+define half @test_f80trunc_nodagcombine() #0 {
+; CHECK-LABEL: test_f80trunc_nodagcombine:
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srhines wrote:
> ab wrote:
> > What do you think of explicitly testing f80->f16 instead?
> Pirama, I think you missed this question. :)
Aah, sorry, I missed this.  I think you mean testing ftrunc from f80 -> say f32 followed by f32 -> f16.  This doesn't trigger the folding because the rounds are not value preserving.


Repository:
  rL LLVM

http://reviews.llvm.org/D17221