[llvm] [RISCV] Enable early if-conversion (PR #92959)

[Pengcheng Wang via llvm-commits]

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@@ -203,3 +211,12 @@ unsigned RISCVSubtarget::getMinimumJumpTableEntries() const {
              ? RISCVMinimumJumpTableEntries
              : TuneInfo->MinimumJumpTableEntries;
 }
+
+bool RISCVSubtarget::enableEarlyIfConversion() const {
+  TargetSchedModel SchedModel;
+  SchedModel.init(this);
+  return RISCVForceEalyIfcvt ||
+         (!RISCVDisableEarlyIfcvt &&
+          (hasStdExtZicond() || hasVendorXVentanaCondOps()) &&
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wangpc-pp wrote:

TODO: Add support for `xtheadcondmov`? cc @zixuan-wu 

https://github.com/llvm/llvm-project/pull/92959