[llvm] [RISCV][llvm] Preliminary P extension codegen support (PR #162668)

[Craig Topper via llvm-commits]

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@@ -1034,6 +1046,14 @@ void RISCVDAGToDAGISel::Select(SDNode *Node) {
     if (!isInt<32>(Imm) && isUInt<32>(Imm) && hasAllWUsers(Node))
       Imm = SignExtend64<32>(Imm);
 
+    if (hasAllWUsers(Node) && isApplicableToPLI(Imm) &&
+        Subtarget->enablePExtCodeGen()) {
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topperc wrote:

Do the enablePExtCodeGen and isApplicableToPLI checks first, hasAllWUsers is expensive.

https://github.com/llvm/llvm-project/pull/162668