[llvm] [GlobalISel] Handle div-by-pow2 (PR #83155)

[Matt Arsenault via llvm-commits]

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@@ -884,3 +786,14 @@ define <2 x i32> @v_sdiv_v2i32_24bit(<2 x i32> %num, <2 x i32> %den) {
   %result = sdiv <2 x i32> %num.mask, %den.mask
   ret <2 x i32> %result
 }
+
+define <2 x i32> @v_sdiv_i32_exact(<2 x i32> %num) {
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arsenm wrote:

Testname is a bit misleading. It's v2i32. Do we have a scalar version of the test? 

https://github.com/llvm/llvm-project/pull/83155