Index: lib/CodeGen/SelectionDAG/SelectionDAG.cpp
===================================================================
--- lib/CodeGen/SelectionDAG/SelectionDAG.cpp
+++ lib/CodeGen/SelectionDAG/SelectionDAG.cpp
@@ -7797,7 +7797,7 @@
 
   // Preserve Debug Info.
   for (unsigned i = 0, e = From->getNumValues(); i != e; ++i)
-    transferDbgValues(SDValue(From, i), *To);
+    transferDbgValues(SDValue(From, i), To[i]);
 
   // Iterate over just the existing users of From. See the comments in
   // the ReplaceAllUsesWith above.
Index: test/DebugInfo/X86/sdag-legalize-multires.ll
===================================================================
--- /dev/null
+++ test/DebugInfo/X86/sdag-legalize-multires.ll
@@ -0,0 +1,48 @@
+; RUN: llc -O0 %s -stop-after=livedebugvars -o - | FileCheck %s
+; This is a hand-crafted example modified after some Swift compiler output.
+; Test that SelectionDAG legalization of DAG nodes with two results
+; transfers debug info correctly.
+
+source_filename = "/tmp/sincos.ll"
+target datalayout = "e-m:o-i64:64-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-apple-macosx10.13.0"
+
+declare float @llvm.cos.f32(float)
+declare float @llvm.sin.f32(float)
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+declare swiftcc void @g(float, float)
+
+; CHECK: ![[RCOS:.*]] = !DILocalVariable(name: "rcos"
+; CHECK: ![[RSIN:.*]] = !DILocalVariable(name: "rsin"
+
+define hidden swiftcc void @f() #0 !dbg !8 {
+entry:
+  ; CHECK: CALL64pcrel32 &__sincosf_stret
+  %0 = call float @llvm.cos.f32(float 1.500000e+00), !dbg !13
+  ; CHECK: $xmm1 = MOVAPSrr $xmm0
+  call void @llvm.dbg.value(metadata float %0, metadata !15, metadata !DIExpression()), !dbg !13
+  ; CHECK: DBG_VALUE debug-use {{.*}}$xmm1, {{.*}}, ![[RSIN]], !DIExpression(),
+  %1 = call float @llvm.sin.f32(float 1.500000e+00), !dbg !13
+  call void @llvm.dbg.value(metadata float %1, metadata !11, metadata !DIExpression()), !dbg !13
+  ; CHECK: DBG_VALUE debug-use {{.*}}$xmm0, {{.*}}, ![[RCOS]], !DIExpression(),
+  call void @g(float %0, float %1), !dbg !13
+  ret void, !dbg !13
+}
+
+attributes #0 = { noinline nounwind optnone ssp uwtable "target-features"="+sse,+sse2,+sse3,+sse4.1,+ssse3,+x87" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 8.0.0 (trunk 340541) (llvm/trunk 340540)", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: None)
+!1 = !DIFile(filename: "sincos.ll", directory: "/")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!8 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 2, type: !9, isLocal: false, isDefinition: true, scopeLine: 2, isOptimized: false, unit: !0, retainedNodes: !2)
+!9 = !DISubroutineType(types: !10)
+!10 = !{null}
+!11 = !DILocalVariable(name: "rsin", scope: !8, file: !1, line: 3, type: !12)
+!12 = !DIBasicType(name: "float", size: 32, encoding: DW_ATE_float)
+!13 = !DILocation(line: 3, scope: !8)
+!15 = !DILocalVariable(name: "rcos", scope: !8, file: !1, line: 4, type: !12)