diff --git a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
--- a/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
+++ b/llvm/lib/Transforms/Vectorize/LoopVectorize.cpp
@@ -1677,7 +1677,10 @@
   /// not matter because we use the 'cost' units to compare different
   /// vector widths. The cost that is returned is *not* normalized by
   /// the factor width.
-  VectorizationCostTy expectedCost(ElementCount VF);
+  VectorizationCostTy expectedCost(
+      ElementCount VF,
+      SmallVectorImpl<std::pair<Instruction *, ElementCount>> *Invalid =
+          nullptr);
 
   /// Returns the execution time cost of an instruction for a given vector
   /// width. Vector width of one means scalar.
@@ -6075,12 +6078,13 @@
     ChosenFactor.Cost = InstructionCost::getMax();
   }
 
+  SmallVector<std::pair<Instruction *, ElementCount>> InvalidCosts;
   for (const auto &i : VFCandidates) {
     // The cost for scalar VF=1 is already calculated, so ignore it.
     if (i.isScalar())
       continue;
 
-    VectorizationCostTy C = expectedCost(i);
+    VectorizationCostTy C = expectedCost(i, &InvalidCosts);
     VectorizationFactor Candidate(i, C.first);
     LLVM_DEBUG(
         dbgs() << "LV: Vector loop of width " << i << " costs: "
@@ -6103,6 +6107,40 @@
       ChosenFactor = Candidate;
   }
 
+  // Emit a report of VFs with invalid costs in the loop, e.g.
+  // remark: Instructions with invalid costs prevent vectorization for certain
+  // VFs:
+  //    call float @llvm.sin(..)  (vscale x 1, vscale x 4)
+  if (!InvalidCosts.empty()) {
+    // Sort/group per instruction
+    llvm::sort(InvalidCosts, [](std::pair<Instruction *, ElementCount> &A,
+                                std::pair<Instruction *, ElementCount> &B) {
+      ElementCountComparator ECC;
+      return A.first < B.first || ECC(A.second, B.second);
+    });
+
+    std::string OutString;
+    raw_string_ostream OS(OutString);
+    OS << "Instructions with invalid costs prevent vectorization for certain "
+          "VFs:\n";
+
+    Instruction *Current = nullptr;
+    for (const auto &InstructionVFPair : InvalidCosts) {
+      if (Current != InstructionVFPair.first) {
+        if (Current != nullptr)
+          OS << ")\n";
+        OS << "\t" << *InstructionVFPair.first << "\t(";
+        Current = InstructionVFPair.first;
+      } else
+        OS << ", ";
+      OS << InstructionVFPair.second;
+    }
+    OS << ")";
+    OS.flush();
+    reportVectorizationInfo(OutString, "InvalidCost", ORE, TheLoop,
+                            InvalidCosts[0].first);
+  }
+
   if (!EnableCondStoresVectorization && NumPredStores) {
     reportVectorizationFailure("There are conditional stores.",
         "store that is conditionally executed prevents vectorization",
@@ -6884,7 +6922,9 @@
 }
 
 LoopVectorizationCostModel::VectorizationCostTy
-LoopVectorizationCostModel::expectedCost(ElementCount VF) {
+LoopVectorizationCostModel::expectedCost(
+    ElementCount VF,
+    SmallVectorImpl<std::pair<Instruction *, ElementCount>> *Invalid) {
   VectorizationCostTy Cost;
 
   // For each block.
@@ -6904,6 +6944,10 @@
       if (ForceTargetInstructionCost.getNumOccurrences() > 0)
         C.first = InstructionCost(ForceTargetInstructionCost);
 
+      // Keep a list of instructions with invalid costs.
+      if (Invalid && !C.first.isValid())
+        Invalid->emplace_back(&I, VF);
+
       BlockCost.first += C.first;
       BlockCost.second |= C.second;
       LLVM_DEBUG(dbgs() << "LV: Found an estimated cost of " << C.first
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/scalable-call.ll b/llvm/test/Transforms/LoopVectorize/AArch64/scalable-call.ll
--- a/llvm/test/Transforms/LoopVectorize/AArch64/scalable-call.ll
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/scalable-call.ll
@@ -1,4 +1,6 @@
-; RUN: opt -S -loop-vectorize -force-vector-interleave=1 -instcombine -mattr=+sve -mtriple aarch64-unknown-linux-gnu -scalable-vectorization=on < %s | FileCheck %s
+; RUN: opt -S -loop-vectorize -force-vector-interleave=1 -instcombine -mattr=+sve -mtriple aarch64-unknown-linux-gnu -scalable-vectorization=on \
+; RUN:     -pass-remarks-missed=loop-vectorize < %s 2>%t | FileCheck %s
+; RUN: cat %t | FileCheck %s --check-prefix=CHECK-REMARKS
 
 define void @vec_load(i64 %N, double* nocapture %a, double* nocapture readonly %b) {
 ; CHECK-LABEL: @vec_load
@@ -95,6 +97,9 @@
   ret void
 }
 
+; CHECK-REMARKS: UserVF ignored because of invalid costs.
+; CHECK-REMARKS-NEXT: Instructions with invalid costs prevent vectorization for certain VFs:
+; CHECK-REMARKS-NEXT:   %1 = tail call fast float @llvm.sin.f32(float %0)     (vscale x 1, vscale x 2)
 define void @vec_sin_no_mapping(float* noalias nocapture %dst, float* noalias nocapture readonly %src, i64 %n) {
 ; CHECK: @vec_sin_no_mapping
 ; CHECK: call fast <2 x float> @llvm.sin.v2f32
@@ -117,6 +122,9 @@
   ret void
 }
 
+; CHECK-REMARKS: UserVF ignored because of invalid costs.
+; CHECK-REMARKS-NEXT: Instructions with invalid costs prevent vectorization for certain VFs:
+; CHECK-REMARKS-NEXT:   %1 = tail call fast float @llvm.sin.f32(float %0) #5  (vscale x 1, vscale x 2)
 define void @vec_sin_fixed_mapping(float* noalias nocapture %dst, float* noalias nocapture readonly %src, i64 %n) {
 ; CHECK: @vec_sin_fixed_mapping
 ; CHECK: call fast <2 x float> @llvm.sin.v2f32