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
@@ -6823,9 +6823,11 @@
     for (Instruction &I : *BB)
       if (isScalarWithPredication(&I)) {
         ScalarCostsTy ScalarCosts;
+        // Do not apply discount if scalable, because that would lead to
+        // invalid scalarization costs.
         // Do not apply discount logic if hacked cost is needed
         // for emulated masked memrefs.
-        if (!useEmulatedMaskMemRefHack(&I) &&
+        if (!VF.isScalable() && !useEmulatedMaskMemRefHack(&I) &&
             computePredInstDiscount(&I, ScalarCosts, VF) >= 0)
           ScalarCostsVF.insert(ScalarCosts.begin(), ScalarCosts.end());
         // Remember that BB will remain after vectorization.
@@ -7624,6 +7626,9 @@
       ScalarPredicatedBB = true;
 
     if (ScalarPredicatedBB) {
+      // Not possible to scalarize scalable vector with predicated instructions.
+      if (VF.isScalable())
+        return InstructionCost::getInvalid();
       // Return cost for branches around scalarized and predicated blocks.
       auto *Vec_i1Ty =
           VectorType::get(IntegerType::getInt1Ty(RetTy->getContext()), VF);
diff --git a/llvm/test/Transforms/LoopVectorize/AArch64/scalable-predicate-instruction.ll b/llvm/test/Transforms/LoopVectorize/AArch64/scalable-predicate-instruction.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/Transforms/LoopVectorize/AArch64/scalable-predicate-instruction.ll
@@ -0,0 +1,95 @@
+; RUN: opt < %s -loop-vectorize -scalable-vectorization=on -S | FileCheck %s
+; RUN: opt < %s -loop-vectorize -scalable-vectorization=on -prefer-predicate-over-epilogue=predicate-dont-vectorize -S | FileCheck %s
+
+target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
+target triple = "aarch64-unknown-linux-gnu"
+
+; The test predication_in_loop corresponds
+; to the following function
+;   for (long long i = 0; i < 1024; i++) {
+;    if (cond[i])
+;      a[i] /= b[i];
+;  }
+
+; Scalarizing the division cannot be done for scalable vectors at the moment
+; when the loop needs predication
+; Future implementation of llvm.vp could allow this to happen
+
+define void  @predication_in_loop(i32* %a, i32* %b, i32* %cond) #0 {
+; CHECK-LABEL: @predication_in_loop
+; CHECK-NOT:  sdiv <vscale x 4 x i32>
+;
+entry:
+  br label %for.body
+
+for.cond.cleanup:                                 ; preds = %for.inc, %entry
+  ret void
+
+for.body:                                         ; preds = %entry, %for.inc
+  %i.09 = phi i64 [ %inc, %for.inc ], [ 0, %entry ]
+  %arrayidx = getelementptr inbounds i32, i32* %cond, i64 %i.09
+  %0 = load i32, i32* %arrayidx, align 4
+  %tobool.not = icmp eq i32 %0, 0
+  br i1 %tobool.not, label %for.inc, label %if.then
+
+if.then:                                          ; preds = %for.body
+  %arrayidx1 = getelementptr inbounds i32, i32* %b, i64 %i.09
+  %1 = load i32, i32* %arrayidx1, align 4
+  %arrayidx2 = getelementptr inbounds i32, i32* %a, i64 %i.09
+  %2 = load i32, i32* %arrayidx2, align 4
+  %div = sdiv i32 %2, %1
+  store i32 %div, i32* %arrayidx2, align 4
+  br label %for.inc
+
+for.inc:                                          ; preds = %for.body, %if.then
+  %inc = add nuw nsw i64 %i.09, 1
+  %exitcond.not = icmp eq i64 %inc, 1024
+  br i1 %exitcond.not, label %for.cond.cleanup, label %for.body, !llvm.loop !0
+}
+
+
+;
+; This test unpredicated_loop_predication_through_tailfolding corresponds
+; to the following function
+;   for (long long i = 0; i < 1024; i++) {
+;      a[i] /= b[i];
+;  }
+
+; Scalarization not possible in the main loop when there is no predication and
+; epilogue should not be able to allow scalarization
+; otherwise it could  be able to vectorize, but will not because
+; "Max legal vector width too small, scalable vectorization unfeasible.."
+
+define void @unpredicated_loop_predication_through_tailfolding(i32* %a, i32* %b) #0 {
+; CHECK-LABEL: @unpredicated_loop_predication_through_tailfolding
+; CHECK-NOT:  sdiv <vscale x 4 x i32>
+
+entry:
+  br label %loop
+
+loop:
+  %iv = phi i64 [ 0, %entry ], [ %iv.next, %loop ]
+  %arrayidx = getelementptr inbounds i32, i32* %a, i64 %iv
+  %0 = load i32, i32* %arrayidx, align 4
+  %arrayidx2 = getelementptr inbounds i32, i32* %b, i64 %iv
+  %1 = load i32, i32* %arrayidx2, align 4
+  %sdiv = sdiv i32 %1, %0
+  %2 = add nuw nsw i64 %iv, 8
+  %arrayidx5 = getelementptr inbounds i32, i32* %a, i64 %2
+  store i32 %sdiv, i32* %arrayidx5, align 4
+  %iv.next = add nuw nsw i64 %iv, 1
+  %exitcond.not = icmp eq i64 %iv.next, 1024
+  br i1 %exitcond.not, label %exit, label %loop, !llvm.loop !0
+
+exit:
+  ret void
+
+}
+
+attributes #0 = { "target-features"="+sve" }
+
+!0 = distinct !{!0, !1, !2, !3, !4}
+!1 = !{!"llvm.loop.vectorize.width", i32 4}
+!2 = !{!"llvm.loop.vectorize.scalable.enable", i1 true}
+!3 = !{!"llvm.loop.interleave.count", i32 1}
+!4 = !{!"llvm.loop.vectorize.enable", i1 true}