Index: lib/Transforms/Utils/BasicBlockUtils.cpp
===================================================================
--- lib/Transforms/Utils/BasicBlockUtils.cpp
+++ lib/Transforms/Utils/BasicBlockUtils.cpp
@@ -486,11 +486,12 @@
   }
 
   // Create new basic block, insert right before the original block.
-  BasicBlock *NewBB = BasicBlock::Create(BB->getContext(), BB->getName()+Suffix,
-                                         BB->getParent(), BB);
+  BasicBlock *NewBB = BasicBlock::Create(
+      BB->getContext(), BB->getName() + Suffix, BB->getParent(), BB);
 
   // The new block unconditionally branches to the old block.
   BranchInst *BI = BranchInst::Create(BB, NewBB);
+  BI->setDebugLoc(BB->getFirstNonPHI()->getDebugLoc());
 
   // Move the edges from Preds to point to NewBB instead of BB.
   for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
@@ -553,6 +554,7 @@
 
   // The new block unconditionally branches to the old block.
   BranchInst *BI1 = BranchInst::Create(OrigBB, NewBB1);
+  BI1->setDebugLoc(OrigBB->getFirstNonPHI()->getDebugLoc());
 
   // Move the edges from Preds to point to NewBB1 instead of OrigBB.
   for (unsigned i = 0, e = Preds.size(); i != e; ++i) {
@@ -593,6 +595,7 @@
 
     // The new block unconditionally branches to the old block.
     BranchInst *BI2 = BranchInst::Create(OrigBB, NewBB2);
+    BI2->setDebugLoc(OrigBB->getFirstNonPHI()->getDebugLoc());
 
     // Move the remaining edges from OrigBB to point to NewBB2.
     for (SmallVectorImpl<BasicBlock*>::iterator
Index: lib/Transforms/Utils/LoopSimplify.cpp
===================================================================
--- lib/Transforms/Utils/LoopSimplify.cpp
+++ lib/Transforms/Utils/LoopSimplify.cpp
@@ -144,8 +144,6 @@
   PreheaderBB = SplitBlockPredecessors(Header, OutsideBlocks, ".preheader",
                                        AA, DT, LI, PreserveLCSSA);
 
-  PreheaderBB->getTerminator()->setDebugLoc(
-                                      Header->getFirstNonPHI()->getDebugLoc());
   DEBUG(dbgs() << "LoopSimplify: Creating pre-header "
                << PreheaderBB->getName() << "\n");
 
Index: test/Transforms/LoopSimplify/dbg-loc.ll
===================================================================
--- /dev/null
+++ test/Transforms/LoopSimplify/dbg-loc.ll
@@ -0,0 +1,56 @@
+; Check that LoopSimplify creates debug locations in synthesized basic blocks.
+; RUN: opt -loop-simplify %s -S -o - | FileCheck %s
+
+; CHECK:       for.body.preheader:
+; CHECK-NEXT:    br label %for.body, !dbg [[PREHEADER_LOC:![0-9]+]]
+; CHECK:       for.end.loopexit:
+; CHECK-NEXT:    br label %for.end, !dbg [[LOOPEXIT_LOC:![0-9]+]]
+; CHECK-DAG: [[PREHEADER_LOC]] = !DILocation(line: 73, column: 27, scope: !{{[0-9]+}})
+; CHECK-DAG: [[LOOPEXIT_LOC]] = !DILocation(line: 75, column: 9, scope: !{{[0-9]+}})
+
+%union.anon = type { i32 }
+%"Length" = type <{ %union.anon, i8, i8, i8, i8 }>
+
+; Function Attrs: nounwind ssp uwtable
+define linkonce_odr hidden void @foo(%"Length"* %begin, %"Length"* %end) #4 align 2 {
+entry:
+  %cmp.4 = icmp eq %"Length"* %begin, %end, !dbg !7
+  br i1 %cmp.4, label %for.end, label %for.body, !dbg !8
+
+for.body:                                         ; preds = %entry, %length.exit
+  %begin.sink5 = phi %"Length"* [ %incdec.ptr, %length.exit ], [ %begin, %entry ]
+  %m_type.i.i.i = getelementptr inbounds %"Length", %"Length"* %begin.sink5, i64 0, i32 2, !dbg !9
+  %0 = load i8, i8* %m_type.i.i.i, align 1, !dbg !9
+  %cmp.i.i = icmp eq i8 %0, 9, !dbg !7
+  br i1 %cmp.i.i, label %if.then.i, label %length.exit, !dbg !8
+
+if.then.i:                                        ; preds = %for.body
+  tail call void @bar(%"Length"* %begin.sink5) #7, !dbg !10
+  br label %length.exit, !dbg !10
+
+length.exit:                        ; preds = %for.body, %if.then.i
+  %incdec.ptr = getelementptr inbounds %"Length", %"Length"* %begin.sink5, i64 1, !dbg !11
+  %cmp = icmp eq %"Length"* %incdec.ptr, %end, !dbg !7
+  br i1 %cmp, label %for.end, label %for.body, !dbg !8
+
+for.end:                                          ; preds = %length.exit, %entry
+  ret void, !dbg !12
+}
+
+declare void @bar(%"Length"*) #3
+
+!llvm.module.flags = !{!0, !1, !2}
+!0 = !{i32 2, !"Dwarf Version", i32 4}
+!1 = !{i32 2, !"Debug Info Version", i32 3}
+!2 = !{i32 1, !"PIC Level", i32 2}
+
+!3 = !{}
+!4 = !DISubroutineType(types: !3)
+!5 = !DIFile(filename: "Vector.h", directory: "/tmp")
+!6 = !DISubprogram(name: "destruct", scope: !5, file: !5, line: 71, type: !4, isLocal: false, isDefinition: true, scopeLine: 72, flags: DIFlagPrototyped, isOptimized: false, function: void (%"Length"*, %"Length"*)* @foo, variables: !3)
+!7 = !DILocation(line: 73, column: 38, scope: !6)
+!8 = !DILocation(line: 73, column: 13, scope: !6)
+!9 = !DILocation(line: 73, column: 27, scope: !6)
+!10 = !DILocation(line: 74, column: 17, scope: !6)
+!11 = !DILocation(line: 73, column: 46, scope: !6)
+!12 = !DILocation(line: 75, column: 9, scope: !6)