Index: lib/Transforms/IPO/PassManagerBuilder.cpp
===================================================================
--- lib/Transforms/IPO/PassManagerBuilder.cpp
+++ lib/Transforms/IPO/PassManagerBuilder.cpp
@@ -661,6 +661,11 @@
   MPM.add(createLoopSinkPass());
   // Get rid of LCSSA nodes.
   MPM.add(createInstructionSimplifierPass());
+
+  // LoopSink (and other loop passes since the last simplifyCFG) might have
+  // resulted in single-entry-single-exit or empty blocks. Clean up the CFG.
+  MPM.add(createCFGSimplificationPass());
+
   addExtensionsToPM(EP_OptimizerLast, MPM);
 }
 
Index: test/Other/pass-pipelines.ll
===================================================================
--- test/Other/pass-pipelines.ll
+++ test/Other/pass-pipelines.ll
@@ -85,6 +85,7 @@
 ; CHECK-O2: FunctionPass Manager
 ; CHECK-O2: Loop Pass Manager
 ; CHECK-O2-NEXT: Loop Sink
+; CHECK-O2: Simplify the CFG
 ; CHECK-O2-NOT: Manager
 ;
 ; FIXME: There really shouldn't be another pass manager, especially one that
Index: test/Other/pr32085.ll
===================================================================
--- /dev/null
+++ test/Other/pr32085.ll
@@ -0,0 +1,119 @@
+; RUN: opt -O2 -S < %s | FileCheck %s
+; In PR32085 we were getting single-entry-single-exit basic blocks due to the
+; lack of cleanup after some loop transformations.
+; Make sure we end up with a single basic block, no branches
+; CHECK-NOT: br label
+
+; ModuleID = 'a.cpp'
+source_filename = "a.cpp"
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.12.0"
+
+; Function Attrs: ssp uwtable
+define i8* @_Z3go4i(i32) #0 {
+  %2 = alloca i32, align 4
+  %3 = alloca i32*, align 8
+  %4 = alloca i32, align 4
+  %5 = alloca i32
+  %6 = alloca i32, align 4
+  store i32 %0, i32* %2, align 4, !tbaa !2
+  %7 = bitcast i32** %3 to i8*
+  call void @llvm.lifetime.start(i64 8, i8* %7) #3
+  %8 = call i8* @_Znam(i64 4096) #4
+  %9 = bitcast i8* %8 to i32*
+  store i32* %9, i32** %3, align 8, !tbaa !6
+  %10 = bitcast i32* %4 to i8*
+  call void @llvm.lifetime.start(i64 4, i8* %10) #3
+  store i32 0, i32* %4, align 4, !tbaa !2
+  br label %11
+
+; <label>:11:                                     ; preds = %36, %1
+  %12 = load i32, i32* %4, align 4, !tbaa !2
+  %13 = icmp slt i32 %12, 8
+  br i1 %13, label %16, label %14
+
+; <label>:14:                                     ; preds = %11
+  store i32 2, i32* %5, align 4
+  %15 = bitcast i32* %4 to i8*
+  call void @llvm.lifetime.end(i64 4, i8* %15) #3
+  br label %39
+
+; <label>:16:                                     ; preds = %11
+  %17 = bitcast i32* %6 to i8*
+  call void @llvm.lifetime.start(i64 4, i8* %17) #3
+  store i32 0, i32* %6, align 4, !tbaa !2
+  br label %18
+
+; <label>:18:                                     ; preds = %32, %16
+  %19 = load i32, i32* %6, align 4, !tbaa !2
+  %20 = icmp slt i32 %19, 128
+  br i1 %20, label %23, label %21
+
+; <label>:21:                                     ; preds = %18
+  store i32 5, i32* %5, align 4
+  %22 = bitcast i32* %6 to i8*
+  call void @llvm.lifetime.end(i64 4, i8* %22) #3
+  br label %35
+
+; <label>:23:                                     ; preds = %18
+  %24 = load i32, i32* %2, align 4, !tbaa !2
+  %25 = load i32*, i32** %3, align 8, !tbaa !6
+  %26 = load i32, i32* %4, align 4, !tbaa !2
+  %27 = mul nsw i32 %26, 128
+  %28 = load i32, i32* %6, align 4, !tbaa !2
+  %29 = add nsw i32 %27, %28
+  %30 = sext i32 %29 to i64
+  %31 = getelementptr inbounds i32, i32* %25, i64 %30
+  store i32 %24, i32* %31, align 4, !tbaa !2
+  br label %32
+
+; <label>:32:                                     ; preds = %23
+  %33 = load i32, i32* %6, align 4, !tbaa !2
+  %34 = add nsw i32 %33, 1
+  store i32 %34, i32* %6, align 4, !tbaa !2
+  br label %18
+
+; <label>:35:                                     ; preds = %21
+  br label %36
+
+; <label>:36:                                     ; preds = %35
+  %37 = load i32, i32* %4, align 4, !tbaa !2
+  %38 = add nsw i32 %37, 1
+  store i32 %38, i32* %4, align 4, !tbaa !2
+  br label %11
+
+; <label>:39:                                     ; preds = %14
+  %40 = load i32*, i32** %3, align 8, !tbaa !6
+  %41 = bitcast i32* %40 to i8*
+  store i32 1, i32* %5, align 4
+  %42 = bitcast i32** %3 to i8*
+  call void @llvm.lifetime.end(i64 8, i8* %42) #3
+  ret i8* %41
+}
+
+; Function Attrs: argmemonly nounwind
+declare void @llvm.lifetime.start(i64, i8* nocapture) #1
+
+; Function Attrs: nobuiltin
+declare noalias i8* @_Znam(i64) #2
+
+; Function Attrs: argmemonly nounwind
+declare void @llvm.lifetime.end(i64, i8* nocapture) #1
+
+attributes #0 = { ssp uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="core-avx2" "target-features"="+aes,+avx,+avx2,+bmi,+bmi2,+cx16,+f16c,+fma,+fsgsbase,+fxsr,+lzcnt,+mmx,+movbe,+pclmul,+popcnt,+rdrnd,+rtm,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsaveopt" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #1 = { argmemonly nounwind }
+attributes #2 = { nobuiltin "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="core-avx2" "target-features"="+aes,+avx,+avx2,+bmi,+bmi2,+cx16,+f16c,+fma,+fsgsbase,+fxsr,+lzcnt,+mmx,+movbe,+pclmul,+popcnt,+rdrnd,+rtm,+sse,+sse2,+sse3,+sse4.1,+sse4.2,+ssse3,+x87,+xsave,+xsaveopt" "unsafe-fp-math"="false" "use-soft-float"="false" }
+attributes #3 = { nounwind }
+attributes #4 = { builtin }
+
+!llvm.module.flags = !{!0}
+!llvm.ident = !{!1}
+
+!0 = !{i32 1, !"PIC Level", i32 2}
+!1 = !{!"clang version 5.0.0 (trunk 296485) (llvm/trunk 296488)"}
+!2 = !{!3, !3, i64 0}
+!3 = !{!"int", !4, i64 0}
+!4 = !{!"omnipotent char", !5, i64 0}
+!5 = !{!"Simple C++ TBAA"}
+!6 = !{!7, !7, i64 0}
+!7 = !{!"any pointer", !4, i64 0}