[PATCH] D21251: [TTI] The cost model should not assume illegal vector casts get completely scalarized

[Matt Arsenault via llvm-commits]

arsenm added inline comments.

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Comment at: test/Analysis/CostModel/AMDGPU/addrspacecast.ll:39
@@ -38,3 +38,3 @@
 ; CHECK: 'addrspacecast_local_to_flat_v32'
-; CHECK: estimated cost of 32 for {{.*}} addrspacecast <32 x i8 addrspace(3)*> %ptr to <32 x i8 addrspace(4)*>
+; CHECK: estimated cost of 47 for {{.*}} addrspacecast <32 x i8 addrspace(3)*> %ptr to <32 x i8 addrspace(4)*>
 define <32 x i8 addrspace(4)*> @addrspacecast_local_to_flat_v32(<32 x i8 addrspace(3)*> %ptr) #0 {
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Pretty much everything should be scalarized. The vector insert and extracts are supposed to be free (and the cost is reported as 0 for those) so I think adding the one there is inconsistent and should check the extract/insert cost


http://reviews.llvm.org/D21251