[llvm] [LoopUnroll] Consider simplified operands while retrieving TTI instruction cost (PR #70929)

[Sergey Kachkov via llvm-commits]

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@@ -50,7 +50,7 @@ for.end:
 }
 
 ; CHECK-LABEL: @test_func_addrspacecast_cost_nonfree(
-; CHECK: br i1 %exitcond
+; CHECK-NOT: br i1 %exitcond
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skachkov-sc wrote:

Unfortunately, with this change it's now impossbile to find threshold that keeps old behavour for all tests in this file. The savings in test_func_addrspacecast_cost_nonfree are higher (I assume that for AMDGPU target GEP with constant offset is cheaper in addrspace(3)), so there is no threshold where first 2 tests are unrolled and the last is not.

https://github.com/llvm/llvm-project/pull/70929