[llvm] [RISCV] Override default sched policy (PR #115445)

[Min-Yih Hsu via llvm-commits]

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@@ -199,3 +200,25 @@ unsigned RISCVSubtarget::getMinimumJumpTableEntries() const {
              ? RISCVMinimumJumpTableEntries
              : TuneInfo->MinimumJumpTableEntries;
 }
+
+void RISCVSubtarget::overrideSchedPolicy(MachineSchedPolicy &Policy,
+                                         unsigned NumRegionInstrs) const {
+  // Do bidirectional scheduling since it provides a more balanced scheduling
+  // leading to better performance. This will increase compile time.
+  Policy.OnlyTopDown = false;
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mshockwave wrote:

IIRC setting OnlyBottomUp to false is sufficient to turn on bidirectional scheduler, since OnlyTopDown is default to false

https://github.com/llvm/llvm-project/pull/115445