[llvm] [RISCV][GISel] Lower G_ABDS and G_ABDU (PR #155888)

[Shaoce SUN via llvm-commits]

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@@ -488,6 +488,8 @@ RISCVLegalizerInfo::RISCVLegalizerInfo(const RISCVSubtarget &ST)
       .minScalar(ST.hasStdExtZbb(), 0, sXLen)
       .lower();
 
+  getActionDefinitionsBuilder({G_ABDS, G_ABDU}).customFor({s8, s16, s32, s64});
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sunshaoce wrote:

I switched to `.lower()` and added a case in `LegalizerHelper::lower()` to forward `G_ABDS/G_ABDU` to `lowerAbsDiffToMinMax`.

https://github.com/llvm/llvm-project/pull/155888