[llvm] [RISCV] Cost UDIV/UREM by a constant power of 2 as a SHL/AND in getArithmeticInstrCost() (PR #179570)

[Luke Lau via llvm-commits]

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@@ -1700,3 +1700,26 @@ define i32 @xor() {
   xor <vscale x 8 x i64> undef, undef
   ret i32 undef
 }
+
+define void @transforms() {
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lukel97 wrote:

Can we add some tests for fixed vectors? With some uniform and non-uniform divisors too

https://github.com/llvm/llvm-project/pull/179570