Max Kazantsev

[IndVars] Miscompile: UB introduced to a simple program by indvars

2

https://godbolt.org/z/xdce1e8P4 Run opt -passes=indvars on the following IR: ``` target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128-ni:1-p2:32:8:8:32-ni:2" target triple = "x86_64-unknown-linux-gnu" define void @test(i32 %tmp) { bb: br label %bb2 bb1: ; preds =...

[LoopVectorize] Clang fails to vectorize simple polynomial hash

1

Here is example of a simple polynomial hash that could not be auto-vectorized with SSE 4.1 (LV could not prove legality): https://godbolt.org/z/86o9zPT51 Original test: ```cpp unsigned rabin_karp_naive(unsigned *s, unsigned len)...