[llvm] [RISCV][GISEL] Legalize, regbank select, and instruction select G_ZEXT, G_SEXT, G_ANYEXT, G_SPLAT_VECTOR, and G_ICMP (PR #85938)

[Matt Arsenault via llvm-commits]

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@@ -141,6 +141,9 @@ RISCVLegalizerInfo::RISCVLegalizerInfo(const RISCVSubtarget &ST)
 
   if (ST.is64Bit()) {
     getActionDefinitionsBuilder({G_ZEXT, G_SEXT, G_ANYEXT})
+        .customIf(typeIsLegalBoolVec(1, BoolVecTys, ST))
+        .legalIf(all(typeIsLegalIntOrFPVec(0, IntOrFPVecTys, ST),
+                     typeIsLegalIntOrFPVec(1, IntOrFPVecTys, ST)))
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arsenm wrote:

legal operations should be preferred as the first action 

https://github.com/llvm/llvm-project/pull/85938