Index: lib/Transforms/Scalar/WarnMissedTransforms.cpp
===================================================================
--- lib/Transforms/Scalar/WarnMissedTransforms.cpp
+++ lib/Transforms/Scalar/WarnMissedTransforms.cpp
@@ -91,6 +91,11 @@
 // New pass manager boilerplate
 PreservedAnalyses
 WarnMissedTransformationsPass::run(Function &F, FunctionAnalysisManager &AM) {
+  // Do not warn about not applied transformations if optimizations are
+  // disabled.
+  if (F.hasFnAttribute(Attribute::OptimizeNone))
+    return PreservedAnalyses::all();
+
   auto &ORE = AM.getResult<OptimizationRemarkEmitterAnalysis>(F);
   auto &LI = AM.getResult<LoopAnalysis>(F);
 
Index: test/Transforms/LoopTransformWarning/optnone.ll
===================================================================
--- /dev/null
+++ test/Transforms/LoopTransformWarning/optnone.ll
@@ -0,0 +1,50 @@
+; Legacy pass manager
+; RUN: opt -transform-warning -disable-output -pass-remarks-missed=transform-warning -pass-remarks-analysis=transform-warning < %s 2>&1 | FileCheck -allow-empty %s
+;
+; New pass manager
+; RUN: opt -passes=transform-warning -disable-output -pass-remarks-missed=transform-warning -pass-remarks-analysis=transform-warning < %s 2>&1 | FileCheck -allow-empty %s
+;
+; Verify that no transformation warnings are emitted for functions with
+; 'optnone' attribute.
+;
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+
+define void @func(i32* nocapture %A, i32* nocapture readonly %B, i32 %Length) #0 {
+entry:
+  %cmp9 = icmp sgt i32 %Length, 0
+  br i1 %cmp9, label %for.body.preheader, label %for.end
+
+for.body.preheader:                          
+  br label %for.body
+
+for.body:                                    
+  %indvars.iv = phi i64 [ %indvars.iv.next, %for.body ], [ 0, %for.body.preheader ]
+  %arrayidx = getelementptr inbounds i32, i32* %B, i64 %indvars.iv
+  %0 = load i32, i32* %arrayidx, align 4
+  %idxprom1 = sext i32 %0 to i64
+  %arrayidx2 = getelementptr inbounds i32, i32* %A, i64 %idxprom1
+  %1 = load i32, i32* %arrayidx2, align 4
+  %arrayidx4 = getelementptr inbounds i32, i32* %A, i64 %indvars.iv
+  store i32 %1, i32* %arrayidx4, align 4
+  %indvars.iv.next = add nuw nsw i64 %indvars.iv, 1
+  %lftr.wideiv = trunc i64 %indvars.iv.next to i32
+  %exitcond = icmp eq i32 %lftr.wideiv, %Length
+  br i1 %exitcond, label %for.end.loopexit, label %for.body, !llvm.loop !0
+
+for.end.loopexit:                            
+  br label %for.end
+
+for.end:                                      
+  ret void
+}
+
+attributes #0 = { noinline optnone }
+
+!0 = distinct !{!0, !1, !2, !3}
+!1 = !{!"llvm.loop.unroll.enable"}
+!2 = !{!"llvm.loop.distribute.enable"}
+!3 = !{!"llvm.loop.unroll_and_jam.enable"}
+!4 = !{!"llvm.loop.vectorize.enable", i1 true}
+
+
+; CHECK-NOT: warning