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Author: Mel-Chen

llvm/test/Transforms/LoopVectorize/RISCV/vectorize-force-tail-with-evl-fixed-order-recurrence.ll

@@ -11,6 +11,10 @@
 ; RUN: -prefer-predicate-over-epilogue=predicate-else-scalar-epilogue \
 ; RUN: -mtriple=riscv64 -mattr=+v,+f -S < %s| FileCheck %s --check-prefix=NO-VP
 
+; FIXME: Fixed-order recurrence is not supported yet with EVL tail folding.
+; The llvm.splice may occurs unexpected behavior if the evl of the
+; second-to-last iteration is not VF*UF.
+
 define void @first_order_recurrence(ptr noalias %A, ptr noalias %B, i64 %TC) {
 ; IF-EVL-LABEL: define void @first_order_recurrence(
 ; IF-EVL-SAME: ptr noalias [[A:%.*]], ptr noalias [[B:%.*]], i64 [[TC:%.*]]) #[[ATTR0:[0-9]+]] {