Index: llvm/trunk/lib/Transforms/Utils/InlineFunction.cpp
===================================================================
--- llvm/trunk/lib/Transforms/Utils/InlineFunction.cpp
+++ llvm/trunk/lib/Transforms/Utils/InlineFunction.cpp
@@ -1350,7 +1350,7 @@
 /// Update inlined instructions' line numbers to
 /// to encode location where these instructions are inlined.
 static void fixupLineNumbers(Function *Fn, Function::iterator FI,
-                             Instruction *TheCall) {
+                             Instruction *TheCall, bool CalleeHasDebugInfo) {
   const DebugLoc &TheCallDL = TheCall->getDebugLoc();
   if (!TheCallDL)
     return;
@@ -1374,6 +1374,8 @@
          BI != BE; ++BI) {
       DebugLoc DL = BI->getDebugLoc();
       if (!DL) {
+        if (CalleeHasDebugInfo)
+          continue;
         // If the inlined instruction has no line number, make it look as if it
         // originates from the call location. This is important for
         // ((__always_inline__, __nodebug__)) functions which must use caller
@@ -1643,8 +1645,11 @@
     if (IFI.CG)
       UpdateCallGraphAfterInlining(CS, FirstNewBlock, VMap, IFI);
 
-    // Update inlined instructions' line number information.
-    fixupLineNumbers(Caller, FirstNewBlock, TheCall);
+    // For 'nodebug' functions, the associated DISubprogram is always null.
+    // Conservatively avoid propagating the callsite debug location to
+    // instructions inlined from a function whose DISubprogram is not null.
+    fixupLineNumbers(Caller, FirstNewBlock, TheCall,
+                     CalledFunc->getSubprogram() != nullptr);
 
     // Clone existing noalias metadata if necessary.
     CloneAliasScopeMetadata(CS, VMap);
Index: llvm/trunk/test/DebugInfo/Generic/inline-debug-loc.ll
===================================================================
--- llvm/trunk/test/DebugInfo/Generic/inline-debug-loc.ll
+++ llvm/trunk/test/DebugInfo/Generic/inline-debug-loc.ll
@@ -0,0 +1,47 @@
+; RUN: opt -inline -S < %s | FileCheck %s
+
+target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
+
+; Function @bar contains instruction %cmp which is not associated to any debug
+; location. This test verifies that the inliner doesn't incorrectly attribute
+; the callsite debug location to %cmp.
+
+define i32 @bar(i32 %a, i32 %b) #0 !dbg !6 {
+entry:
+  %inc = add i32 %a, 1, !dbg !8
+  %cmp = icmp slt i32 %inc, %b
+  %select = select i1 %cmp, i32 %a, i32 %b, !dbg !8
+  ret i32 %select, !dbg !8
+}
+
+
+; CHECK-LABEL: define i32 @baz(
+; CHECK: entry:
+; CHECK:   %[[INC:[a-z0-9.]+]] = add i32 %a, 1, !dbg ![[DL:[0-9]+]]
+; CHECK:   %[[CMP:[a-z0-9.]+]] = icmp slt i32 %[[INC]], %b
+; CHECK-NOT: !dbg
+; CHECK:   %[[SELECT:[a-z0-9.]+]] = select i1 %[[CMP]], i32 %a, i32 %b, !dbg ![[DL]]
+;
+; ![[DL]] = !DILocation(line: 3, scope: !{{.*}}, inlinedAt: {{.*}})
+
+define i32 @baz(i32 %a, i32 %b) !dbg !9 {
+entry:
+  %call = tail call i32 @bar(i32 %a, i32 %b), !dbg !10
+  ret i32 %call, !dbg !10
+}
+
+attributes #0 = { alwaysinline }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, isOptimized: true, runtimeVersion: 0, emissionKind: LineTablesOnly, enums: !2)
+!1 = !DIFile(filename: "test.c", directory: "")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!6 = distinct !DISubprogram(name: "bar", scope: !1, file: !1, line: 2, type: !7, isLocal: false, isDefinition: true, scopeLine: 2, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !2)
+!7 = !DISubroutineType(types: !2)
+!8 = !DILocation(line: 3, scope: !6)
+!9 = distinct !DISubprogram(name: "baz", scope: !1, file: !1, line: 11, type: !7, isLocal: false, isDefinition: true, scopeLine: 11, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !2)
+!10 = !DILocation(line: 12, scope: !9)