[llvm] [TLI] ReplaceWithVecLib pass uses CostModel (PR #78688)

[Graham Hunter via llvm-commits]

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@@ -428,7 +428,7 @@ define <vscale x 4 x float> @llvm_sin_vscale_f32(<vscale x 4 x float> %in) #0 {
 define <2 x double> @frem_f64(<2 x double> %in) {
 ; CHECK-LABEL: define <2 x double> @frem_f64
 ; CHECK-SAME: (<2 x double> [[IN:%.*]]) {
-; CHECK-NEXT:    [[TMP1:%.*]] = call <2 x double> @armpl_vfmodq_f64(<2 x double> [[IN]], <2 x double> [[IN]])
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huntergr-arm wrote:

Might be a good idea to add a flag to ReplaceWithVeclib.cpp to override the cost for testing purposes. Then filter for call or frem with the autogenerator, and add a second runline using the flag to make sure we still perform the transformation.

https://github.com/llvm/llvm-project/pull/78688