diff --git a/llvm/lib/Target/X86/X86AvoidStoreForwardingBlocks.cpp b/llvm/lib/Target/X86/X86AvoidStoreForwardingBlocks.cpp
index 11a3ff1bd57e..3ac0b1ae5143 100644
--- a/llvm/lib/Target/X86/X86AvoidStoreForwardingBlocks.cpp
+++ b/llvm/lib/Target/X86/X86AvoidStoreForwardingBlocks.cpp
@@ -406,9 +406,7 @@ void X86AvoidSFBPass::buildCopy(MachineInstr *LoadInst, unsigned NLoadOpcode,
   // If the load and store are consecutive, use the loadInst location to
   // reduce register pressure.
   MachineInstr *StInst = StoreInst;
-  auto PrevInstrIt = skipDebugInstructionsBackward(
-      std::prev(MachineBasicBlock::instr_iterator(StoreInst)), MBB->instr_begin());
-  if (PrevInstrIt.getNodePtr() == LoadInst)
+  if (StoreInst->getPrevNode() == LoadInst)
     StInst = LoadInst;
   MachineInstr *NewStore =
       BuildMI(*MBB, StInst, StInst->getDebugLoc(), TII->get(NStoreOpcode))
@@ -532,7 +530,7 @@ void X86AvoidSFBPass::findPotentiallylBlockedCopies(MachineFunction &MF) {
       if (!isPotentialBlockedMemCpyLd(MI.getOpcode()))
         continue;
       int DefVR = MI.getOperand(0).getReg();
-      if (!MRI->hasOneNonDBGUse(DefVR))
+      if (!MRI->hasOneUse(DefVR))
         continue;
       for (auto UI = MRI->use_nodbg_begin(DefVR), UE = MRI->use_nodbg_end();
            UI != UE;) {
diff --git a/llvm/test/CodeGen/X86/avoid-sfb-g-no-change.mir b/llvm/test/CodeGen/X86/avoid-sfb-g-no-change.mir
deleted file mode 100644
index b78bb4c0bea9..000000000000
--- a/llvm/test/CodeGen/X86/avoid-sfb-g-no-change.mir
+++ /dev/null
@@ -1,248 +0,0 @@
-# RUN: llc %s -run-pass x86-avoid-SFB -mtriple=x86_64-unknown-linux-gnu -o - | FileCheck %s -check-prefixes DEBUG-LABEL,CHECK
-# RUN: llc %s -run-pass x86-avoid-SFB -mtriple=x86_64-unknown-linux-gnu -o - | FileCheck %s -check-prefixes NODEBUG-LABEL,CHECK
-#
-# This was generated from:
-#
-# using alpha = float __attribute__((ext_vector_type(4)));
-#
-# void bravo(alpha charlie) {
-#   unsigned char *delta = (unsigned char *)&charlie;
-#   delta[0] = 0;
-#   volatile alpha echo = charlie;
-# }
-#
-# Using the command line:
-# clang -g -c 1.cpp -O2 -S -emit-llvm -fno-strict-aliasing --target=x86_64-unknown-unknown -o test.ll
-
---- |
-  ; ModuleID = 'test.ll'
-  source_filename = "1.cpp"
-  target datalayout = "e-m:e-i64:64-f80:128-n8:16:32:64-S128"
-  target triple = "x86_64-unknown-unknown"
-
-  ; Function Attrs: nounwind uwtable
-  define dso_local void @debug(<4 x float> %charlie) local_unnamed_addr #0 !dbg !10 {
-  entry:
-    %charlie.addr = alloca <4 x float>, align 16
-    %echo = alloca <4 x float>, align 16
-    call void @llvm.dbg.value(metadata <4 x float> %charlie, metadata !19, metadata !DIExpression()), !dbg !23
-    store <4 x float> %charlie, <4 x float>* %charlie.addr, align 16
-    call void @llvm.dbg.value(metadata i8* undef, metadata !20, metadata !DIExpression()), !dbg !24
-    %charlie.addr.0.charlie.addr.0.arrayidx.sroa_cast = bitcast <4 x float>* %charlie.addr to i8*, !dbg !25
-    store i8 0, i8* %charlie.addr.0.charlie.addr.0.arrayidx.sroa_cast, align 16, !dbg !25
-    %echo.0.echo.0..sroa_cast = bitcast <4 x float>* %echo to i8*, !dbg !26
-    call void @llvm.lifetime.start.p0i8(i64 16, i8* nonnull %echo.0.echo.0..sroa_cast), !dbg !26
-    call void @llvm.dbg.declare(metadata <4 x float>* %echo, metadata !21, metadata !DIExpression()), !dbg !27
-    %charlie.addr.0.charlie.addr.0. = load <4 x float>, <4 x float>* %charlie.addr, align 16, !dbg !28
-    call void @llvm.dbg.value(metadata <4 x float> %charlie.addr.0.charlie.addr.0., metadata !19, metadata !DIExpression()), !dbg !23
-    store volatile <4 x float> %charlie.addr.0.charlie.addr.0., <4 x float>* %echo, align 16, !dbg !27
-    call void @llvm.lifetime.end.p0i8(i64 16, i8* nonnull %echo.0.echo.0..sroa_cast), !dbg !29
-    ret void, !dbg !29
-  }
-
-  ; Function Attrs: nounwind uwtable
-  define dso_local void @nodebug(<4 x float> %charlie) local_unnamed_addr #0 {
-  entry:
-    %charlie.addr = alloca <4 x float>, align 16
-    %echo = alloca <4 x float>, align 16
-    store <4 x float> %charlie, <4 x float>* %charlie.addr, align 16
-    %charlie.addr.0.charlie.addr.0.arrayidx.sroa_cast = bitcast <4 x float>* %charlie.addr to i8*
-    store i8 0, i8* %charlie.addr.0.charlie.addr.0.arrayidx.sroa_cast, align 16
-    %echo.0.echo.0..sroa_cast = bitcast <4 x float>* %echo to i8*
-    call void @llvm.lifetime.start.p0i8(i64 16, i8* nonnull %echo.0.echo.0..sroa_cast)
-    %charlie.addr.0.charlie.addr.0. = load <4 x float>, <4 x float>* %charlie.addr, align 16
-    store volatile <4 x float> %charlie.addr.0.charlie.addr.0., <4 x float>* %echo, align 16
-    call void @llvm.lifetime.end.p0i8(i64 16, i8* nonnull %echo.0.echo.0..sroa_cast)
-    ret void
-  }
-
-  ; Function Attrs: nounwind readnone speculatable
-  declare void @llvm.dbg.declare(metadata, metadata, metadata) #1
-
-  ; Function Attrs: argmemonly nounwind
-  declare void @llvm.lifetime.start.p0i8(i64 immarg, i8* nocapture) #2
-
-  ; Function Attrs: argmemonly nounwind
-  declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture) #2
-
-  ; Function Attrs: nounwind readnone speculatable
-  declare void @llvm.dbg.value(metadata, metadata, metadata) #1
-
-  ; Function Attrs: nounwind
-  declare void @llvm.stackprotector(i8*, i8**) #3
-
-  attributes #0 = { nounwind uwtable "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="128" "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"="x86-64" "target-features"="+cx8,+fxsr,+mmx,+sse,+sse2,+x87" "unsafe-fp-math"="false" "use-soft-float"="false" }
-  attributes #1 = { nounwind readnone speculatable }
-  attributes #2 = { argmemonly nounwind }
-  attributes #3 = { nounwind }
-
-  !llvm.dbg.cu = !{!0}
-  !llvm.module.flags = !{!6, !7, !8}
-  !llvm.ident = !{!9}
-
-  !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 9.0.0 (https://github.com/llvm/llvm-project.git dfaba1587d4c17409f28c4be46b184fb77237e8e)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
-  !1 = !DIFile(filename: "1.cpp", directory: "C:\5CUsers\5Cgbdawsoc\5CDocuments\5Cllvm\5Cbg40969")
-  !2 = !{}
-  !3 = !{!4}
-  !4 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !5, size: 64)
-  !5 = !DIBasicType(name: "unsigned char", size: 8, encoding: DW_ATE_unsigned_char)
-  !6 = !{i32 2, !"Dwarf Version", i32 4}
-  !7 = !{i32 2, !"Debug Info Version", i32 3}
-  !8 = !{i32 1, !"wchar_size", i32 4}
-  !9 = !{!"clang version 9.0.0 (https://github.com/llvm/llvm-project.git dfaba1587d4c17409f28c4be46b184fb77237e8e)"}
-  !10 = distinct !DISubprogram(name: "bravo", linkageName: "_Z5bravoDv4_f", scope: !1, file: !1, line: 3, type: !11, scopeLine: 3, flags: DIFlagPrototyped, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !18)
-  !11 = !DISubroutineType(types: !12)
-  !12 = !{null, !13}
-  !13 = !DIDerivedType(tag: DW_TAG_typedef, name: "alpha", file: !1, line: 1, baseType: !14)
-  !14 = !DICompositeType(tag: DW_TAG_array_type, baseType: !15, size: 128, flags: DIFlagVector, elements: !16)
-  !15 = !DIBasicType(name: "float", size: 32, encoding: DW_ATE_float)
-  !16 = !{!17}
-  !17 = !DISubrange(count: 4)
-  !18 = !{!19, !20, !21}
-  !19 = !DILocalVariable(name: "charlie", arg: 1, scope: !10, file: !1, line: 3, type: !13)
-  !20 = !DILocalVariable(name: "delta", scope: !10, file: !1, line: 4, type: !4)
-  !21 = !DILocalVariable(name: "echo", scope: !10, file: !1, line: 6, type: !22)
-  !22 = !DIDerivedType(tag: DW_TAG_volatile_type, baseType: !13)
-  !23 = !DILocation(line: 3, column: 18, scope: !10)
-  !24 = !DILocation(line: 4, column: 18, scope: !10)
-  !25 = !DILocation(line: 5, column: 12, scope: !10)
-  !26 = !DILocation(line: 6, column: 3, scope: !10)
-  !27 = !DILocation(line: 6, column: 18, scope: !10)
-  !28 = !DILocation(line: 6, column: 25, scope: !10)
-  !29 = !DILocation(line: 7, column: 1, scope: !10)
-
-...
----
-name:            debug
-alignment:       4
-exposesReturnsTwice: false
-legalized:       false
-regBankSelected: false
-selected:        false
-failedISel:      false
-tracksRegLiveness: true
-hasWinCFI:       false
-registers:
-  - { id: 0, class: vr128, preferred-register: '' }
-  - { id: 1, class: vr128, preferred-register: '' }
-liveins:
-  - { reg: '$xmm0', virtual-reg: '%0' }
-frameInfo:
-  isFrameAddressTaken: false
-  isReturnAddressTaken: false
-  hasStackMap:     false
-  hasPatchPoint:   false
-  stackSize:       0
-  offsetAdjustment: 0
-  maxAlignment:    16
-  adjustsStack:    false
-  hasCalls:        false
-  stackProtector:  ''
-  maxCallFrameSize: 4294967295
-  cvBytesOfCalleeSavedRegisters: 0
-  hasOpaqueSPAdjustment: false
-  hasVAStart:      false
-  hasMustTailInVarArgFunc: false
-  localFrameSize:  0
-  savePoint:       ''
-  restorePoint:    ''
-fixedStack:      []
-stack:
-  - { id: 0, name: charlie.addr, type: default, offset: 0, size: 16, alignment: 16,
-      stack-id: 0, callee-saved-register: '', callee-saved-restored: true,
-      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
-  - { id: 1, name: echo, type: default, offset: 0, size: 16, alignment: 16,
-      stack-id: 0, callee-saved-register: '', callee-saved-restored: true,
-      debug-info-variable: '!21', debug-info-expression: '!DIExpression()',
-      debug-info-location: '!27' }
-constants:       []
-machineFunctionInfo: {}
-body:             |
-  bb.0.entry:
-    liveins: $xmm0
-
-    DBG_VALUE $xmm0, $noreg, !19, !DIExpression(), debug-location !23
-    %0:vr128 = COPY $xmm0
-    DBG_VALUE %0, $noreg, !19, !DIExpression(), debug-location !23
-    MOVAPSmr %stack.0.charlie.addr, 1, $noreg, 0, $noreg, %0 :: (store 16 into %ir.charlie.addr)
-    DBG_VALUE $noreg, $noreg, !20, !DIExpression(), debug-location !24
-    MOV8mi %stack.0.charlie.addr, 1, $noreg, 0, $noreg, 0, debug-location !25 :: (store 1 into %ir.charlie.addr.0.charlie.addr.0.arrayidx.sroa_cast, align 16)
-    %1:vr128 = MOVAPSrm %stack.0.charlie.addr, 1, $noreg, 0, $noreg, debug-location !28 :: (dereferenceable load 16 from %ir.charlie.addr)
-    DBG_VALUE %1, $noreg, !19, !DIExpression(), debug-location !23
-    MOVAPSmr %stack.1.echo, 1, $noreg, 0, $noreg, killed %1, debug-location !27 :: (volatile store 16 into %ir.echo)
-    RET 0, debug-location !29
-
-...
----
-name:            nodebug
-alignment:       4
-exposesReturnsTwice: false
-legalized:       false
-regBankSelected: false
-selected:        false
-failedISel:      false
-tracksRegLiveness: true
-hasWinCFI:       false
-registers:
-  - { id: 0, class: vr128, preferred-register: '' }
-  - { id: 1, class: vr128, preferred-register: '' }
-liveins:
-  - { reg: '$xmm0', virtual-reg: '%0' }
-frameInfo:
-  isFrameAddressTaken: false
-  isReturnAddressTaken: false
-  hasStackMap:     false
-  hasPatchPoint:   false
-  stackSize:       0
-  offsetAdjustment: 0
-  maxAlignment:    16
-  adjustsStack:    false
-  hasCalls:        false
-  stackProtector:  ''
-  maxCallFrameSize: 4294967295
-  cvBytesOfCalleeSavedRegisters: 0
-  hasOpaqueSPAdjustment: false
-  hasVAStart:      false
-  hasMustTailInVarArgFunc: false
-  localFrameSize:  0
-  savePoint:       ''
-  restorePoint:    ''
-fixedStack:      []
-stack:
-  - { id: 0, name: charlie.addr, type: default, offset: 0, size: 16, alignment: 16,
-      stack-id: 0, callee-saved-register: '', callee-saved-restored: true,
-      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
-  - { id: 1, name: echo, type: default, offset: 0, size: 16, alignment: 16,
-      stack-id: 0, callee-saved-register: '', callee-saved-restored: true,
-      debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
-constants:       []
-machineFunctionInfo: {}
-body:             |
-  bb.0.entry:
-    liveins: $xmm0
-
-    %0:vr128 = COPY $xmm0
-    MOVAPSmr %stack.0.charlie.addr, 1, $noreg, 0, $noreg, %0 :: (store 16 into %ir.charlie.addr)
-    MOV8mi %stack.0.charlie.addr, 1, $noreg, 0, $noreg, 0 :: (store 1 into %ir.charlie.addr.0.charlie.addr.0.arrayidx.sroa_cast, align 16)
-    %1:vr128 = MOVAPSrm %stack.0.charlie.addr, 1, $noreg, 0, $noreg :: (dereferenceable load 16 from %ir.charlie.addr)
-    MOVAPSmr %stack.1.echo, 1, $noreg, 0, $noreg, killed %1 :: (volatile store 16 into %ir.echo)
-    RET 0
-
-    ; DEBUG-LABEL: name: debug
-    ; NODEBUG-LABEL: name: nodebug
-    ; CHECK: %0:vr128 = COPY $xmm0
-    ; CHECK: MOVAPSmr
-    ; CHECK: MOV8mi
-    ; ChECK: %2:gr8 = MOV8rm
-    ; CHECK: MOV8mr
-    ; CHECK: %3:gr64 = MOV64rm
-    ; CHECK: MOV64mr
-    ; CHECK: %4:gr32 = MOV32rm
-    ; CHECK: MOV32mr
-    ; CHECK: %5:gr16 = MOV16rm
-    ; CHECK: MOV16mr
-    ; CHECK: %6:gr8 = MOV8rm
-    ; CHECK: MOV8mr
-    ; CHECK: RET 0
-    ; DEBUG-LABEL: name: nodebug
-...