Index: llvm/lib/CodeGen/GlobalISel/InstructionSelect.cpp
===================================================================
--- llvm/lib/CodeGen/GlobalISel/InstructionSelect.cpp
+++ llvm/lib/CodeGen/GlobalISel/InstructionSelect.cpp
@@ -174,8 +174,8 @@
         auto SrcRC = MRI.getRegClass(SrcReg);
         auto DstRC = MRI.getRegClass(DstReg);
         if (SrcRC == DstRC) {
-          MRI.replaceRegWith(DstReg, SrcReg);
           MI.eraseFromParentAndMarkDBGValuesForRemoval();
+          MRI.replaceRegWith(DstReg, SrcReg);
         }
       }
     }
Index: llvm/test/DebugInfo/AArch64/kk3.ll
===================================================================
--- /dev/null
+++ llvm/test/DebugInfo/AArch64/kk3.ll
@@ -0,0 +1,51 @@
+; RUN: llc -global-isel=1 -filetype=obj -mtriple=aarch64-linux-gnu -o - %s | llvm-dwarfdump -v - | FileCheck %s
+;
+; CHECK: .debug_info contents:
+; CHECK: DW_TAG_formal_parameter
+; CHECK: DW_AT_location
+
+
+%struct.mystruct = type { double, double, double, double, double }
+
+@.str = private unnamed_addr constant [5 x i8] c"%llu\00", align 1
+define dso_local void @foo(%struct.mystruct* %ms) !dbg !9 {
+entry:
+  call void @llvm.dbg.declare(metadata %struct.mystruct* %ms, metadata !21, metadata !DIExpression()), !dbg !22
+  %0 = ptrtoint %struct.mystruct* %ms to i64, !dbg !23
+  %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([5 x i8], [5 x i8]* @.str, i64 0, i64 0), i64 %0), !dbg !24
+  ret void, !dbg !25
+}
+declare void @llvm.dbg.declare(metadata, metadata, metadata)
+declare dso_local i32 @printf(i8*, ...)
+
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!5, !6, !7}
+!llvm.ident = !{!8}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: false, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, splitDebugInlining: false, nameTableKind: None)
+!1 = !DIFile(filename: ".", directory: ".")
+!2 = !{}
+!3 = !{!4}
+!4 = !DIBasicType(name: "long long unsigned int", size: 64, encoding: DW_ATE_unsigned)
+!5 = !{i32 7, !"Dwarf Version", i32 4}
+!6 = !{i32 2, !"Debug Info Version", i32 3}
+!7 = !{i32 1, !"wchar_size", i32 4}
+!8 = !{!"clang version 10.0.0"}
+!9 = distinct !DISubprogram(name: "foo", scope: !1, file: !1, line: 5, type: !10, scopeLine: 5, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition, unit: !0, retainedNodes: !2)
+!10 = !DISubroutineType(types: !11)
+!11 = !{null, !12}
+!12 = !DIDerivedType(tag: DW_TAG_typedef, name: "mystruct", file: !1, line: 3, baseType: !13)
+!13 = distinct !DICompositeType(tag: DW_TAG_structure_type, file: !1, line: 1, size: 320, elements: !14)
+!14 = !{!15, !17, !18, !19, !20}
+!15 = !DIDerivedType(tag: DW_TAG_member, name: "a", scope: !13, file: !1, line: 2, baseType: !16, size: 64)
+!16 = !DIBasicType(name: "double", size: 64, encoding: DW_ATE_float)
+!17 = !DIDerivedType(tag: DW_TAG_member, name: "b", scope: !13, file: !1, line: 2, baseType: !16, size: 64, offset: 64)
+!18 = !DIDerivedType(tag: DW_TAG_member, name: "c", scope: !13, file: !1, line: 2, baseType: !16, size: 64, offset: 128)
+!19 = !DIDerivedType(tag: DW_TAG_member, name: "d", scope: !13, file: !1, line: 2, baseType: !16, size: 64, offset: 192)
+!20 = !DIDerivedType(tag: DW_TAG_member, name: "e", scope: !13, file: !1, line: 2, baseType: !16, size: 64, offset: 256)
+!21 = !DILocalVariable(name: "ms", arg: 1, scope: !9, file: !1, line: 5, type: !12)
+!22 = !DILocation(line: 5, column: 19, scope: !9)
+!23 = !DILocation(line: 7, column: 1, scope: !9)
+!24 = !DILocation(line: 6, column: 5, scope: !9)
+!25 = !DILocation(line: 8, column: 1, scope: !9)