[llvm] [DAGCombiner] Fix exact power-of-two signed division for large integers (PR #177340)

[Matt Arsenault via llvm-commits]

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@@ -4373,6 +4373,115 @@ define i128 @v_sdiv_i128_v_pow2k(i128 %lhs) {
   ret i128 %div
 }
 
+define i128 @v_sdiv_exact_i128_v_pow2k(i128 %lhs) {
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arsenm wrote:

This was #176304 (and maybe another)?

https://github.com/llvm/llvm-project/pull/177340