[clang] [llvm] [CIR] Support x86 builtin rotate (PR #169566)

[Omar Hossam via llvm-commits]

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@@ -90,6 +92,41 @@ static mlir::Value getMaskVecValue(CIRGenFunction &cgf, const CallExpr *expr,
   return maskVec;
 }
 
+static mlir::Value emitX86FunnelShift(CIRGenFunction &cgf, const CallExpr *e,
+                                      mlir::Value &op0, mlir::Value &op1,
+                                      mlir::Value &amt, bool isRight) {
+  auto &builder = cgf.getBuilder();
+  auto op0Ty = op0.getType();
+
+  // Amount may be scalar immediate, in which case create a splat vector.
+  // Funnel shifts amounts are treated as modulo and types are all power-of-2
+  // so we only care about the lowest log2 bits anyway.
+  if (amt.getType() != op0Ty) {
+    auto vecTy = mlir::cast<cir::VectorType>(op0Ty);
+    auto numElems = vecTy.getSize();
+
+    auto amtTy = mlir::cast<cir::IntType>(amt.getType());
+    auto vecElemTy = mlir::cast<cir::IntType>(vecTy.getElementType());
+
+    // Cast to same width unsigned if not already unsigned.
+    if (amtTy.isSigned()) {
+      auto unsignedAmtTy = builder.getUIntNTy(amtTy.getWidth());
+      amt = builder.createIntCast(amt,
+                                  builder.getUIntNTy(unsignedAmtTy.getWidth()));
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moar55 wrote:

Ah yes, oops

https://github.com/llvm/llvm-project/pull/169566