[CIR] Backport VecCreateOp Folder

clang/include/clang/CIR/Dialect/IR/CIROps.td

@@ -3107,6 +3107,7 @@ def VecCreateOp : CIR_Op<"vec.create", [Pure]> {
   }];
 
   let hasVerifier = 1;
+  let hasFolder = 1;
 }
 
 //===----------------------------------------------------------------------===//

clang/lib/CIR/Dialect/IR/CIRDialect.cpp

@@ -1011,6 +1011,16 @@ void cir::StoreOp::setAtomic(cir::MemOrder order) {
 // VecCreateOp
 //===----------------------------------------------------------------------===//
 
+OpFoldResult cir::VecCreateOp::fold(FoldAdaptor adaptor) {
+  if (llvm::any_of(getElements(), [](mlir::Value value) {
+        return !mlir::isa<cir::ConstantOp>(value.getDefiningOp());
+      }))
+    return {};
+
+  return cir::ConstVectorAttr::get(
+      getType(), mlir::ArrayAttr::get(getContext(), adaptor.getElements()));
+}
+
 LogicalResult cir::VecCreateOp::verify() {
   // Verify that the number of arguments matches the number of elements in the
   // vector, and that the type of all the arguments matches the type of the

clang/lib/CIR/Dialect/Transforms/CIRCanonicalize.cpp

@@ -179,7 +179,7 @@ void CIRCanonicalizePass::runOnOperation() {
     // CastOp, UnaryOp and VecExtractOp are here to perform a manual `fold` in
     // applyOpPatternsGreedily.
     if (isa<BrOp, BrCondOp, ScopeOp, SwitchOp, CastOp, TryOp, UnaryOp, SelectOp,
-            ComplexCreateOp, ComplexRealOp, ComplexImagOp, CallOp,
+            ComplexCreateOp, ComplexRealOp, ComplexImagOp, CallOp, VecCreateOp,
             VecExtractOp>(op))
       ops.push_back(op);
   });

clang/test/CIR/Transforms/vector-create-fold.cir

@@ -0,0 +1,19 @@
+// RUN: cir-opt %s -cir-canonicalize -o - | FileCheck %s
+
+!s32i = !cir.int<s, 32>
+
+module  {
+  cir.func @fold_create_vector_op_test() -> !cir.vector<!s32i x 4> {
+    %2 = cir.const #cir.int<1> : !s32i
+    %3 = cir.const #cir.int<2> : !s32i
+    %4 = cir.const #cir.int<3> : !s32i
+    %5 = cir.const #cir.int<4> : !s32i
+    %vec = cir.vec.create(%2, %3, %4, %5 : !s32i, !s32i, !s32i, !s32i) : !cir.vector<!s32i x 4>
+    cir.return %vec : !cir.vector<!s32i x 4>
+  }
+
+  // CHECK:  cir.func @fold_create_vector_op_test() -> !cir.vector<!s32i x 4> {
+  // CHECK-NEXT: %[[VEC:.*]] = cir.const #cir.const_vector<[#cir.int<1> : !s32i, #cir.int<2> : !s32i,
+  // CHECK-SAME: #cir.int<3> : !s32i, #cir.int<4> : !s32i]> : !cir.vector<!s32i x 4>
+  // CHECK-NEXT: cir.return %[[VEC]] : !cir.vector<!s32i x 4>
+}