Index: lib/Target/X86/X86CmovConversion.cpp
===================================================================
--- lib/Target/X86/X86CmovConversion.cpp
+++ lib/Target/X86/X86CmovConversion.cpp
@@ -263,6 +263,9 @@
     bool SkipGroup = false;
 
     for (auto &I : *MBB) {
+      // Skip DBG instructions.
+      if (I.isDebugValue())
+        continue;
       X86::CondCode CC = X86::getCondFromCMovOpc(I.getOpcode());
       // Check if we found a X86::CMOVrr instruction.
       if (CC != X86::COND_INVALID && (IncludeLoads || !I.mayLoad())) {
@@ -400,6 +403,9 @@
       // Clear physical registers Def map.
       RegDefMaps[PhyRegType].clear();
       for (MachineInstr &MI : *MBB) {
+        // Skip DBG instructions.
+        if (MI.isDebugValue())
+          continue;
         unsigned MIDepth = 0;
         unsigned MIDepthOpt = 0;
         bool IsCMOV = CmovInstructions.count(&MI);
@@ -612,6 +618,17 @@
   MachineFunction *F = MBB->getParent();
   const BasicBlock *BB = MBB->getBasicBlock();
 
+  // If there are DBG instructions between first CMOV and last CMOV, move them
+  // to after the last CMOV.
+  MachineBasicBlock::iterator DbgIt = MI.getIterator();
+  MachineBasicBlock::iterator DbgE = LastCMOV->getIterator();
+  while (DbgIt != DbgE) {
+    MachineInstr &I = *DbgIt++;
+    if (I.isDebugValue()) {
+      MBB->insertAfter(DbgE, I.removeFromParent());
+    }
+  }
+
   MachineBasicBlock *FalseMBB = F->CreateMachineBasicBlock(BB);
   MachineBasicBlock *SinkMBB = F->CreateMachineBasicBlock(BB);
   F->insert(It, FalseMBB);
Index: test/CodeGen/X86/PR34565.ll
===================================================================
--- test/CodeGen/X86/PR34565.ll
+++ test/CodeGen/X86/PR34565.ll
@@ -0,0 +1,60 @@
+; RUN: llc -mtriple=x86_64-pc-linux -x86-cmov-converter=true -verify-machineinstrs < %s | FileCheck %s
+
+; Test for PR34565, check that DBG instructions are ignored while optimizing
+; X86 CMOV instructions.
+; In this case, we check that there is no 'cmov' generated.
+
+; CHECK-NOT: cmov
+
+@main.buf = private unnamed_addr constant [10 x i64] [i64 0, i64 1, i64 2, i64 3, i64 4, i64 5, i64 6, i64 7, i64 8, i64 9], align 8
+
+define i32 @main() #0 !dbg !5 {
+entry:
+  br label %while.body
+
+while.body:                                       ; preds = %while.body, %entry
+  %a.010 = phi i32 [ 0, %entry ], [ %add.a.0, %while.body ]
+  %b.09 = phi i32 [ 10, %entry ], [ %b.0.add, %while.body ]
+  %add = add i32 %a.010, %b.09
+  %call = tail call i32 @rand()
+  %conv = sext i32 %call to i64
+  %arrayidx = getelementptr inbounds [10 x i64], [10 x i64]* @main.buf, i32 0, i32 %add
+  %0 = load i64, i64* %arrayidx, align 8
+  %cmp1 = icmp ult i64 %0, %conv
+  %b.0.add = select i1 %cmp1, i32 %b.09, i32 %add
+  %add.a.0 = select i1 %cmp1, i32 %add, i32 %a.010
+  tail call void @llvm.dbg.value(metadata i32 %add.a.0, metadata !10, metadata !DIExpression()), !dbg !13
+  tail call void @llvm.dbg.value(metadata i32 %b.0.add, metadata !12, metadata !DIExpression()), !dbg !14
+  tail call void @llvm.dbg.value(metadata i32 %add.a.0, metadata !10, metadata !DIExpression()), !dbg !13
+  tail call void @llvm.dbg.value(metadata i32 %b.0.add, metadata !12, metadata !DIExpression()), !dbg !14
+  %cmp = icmp ult i32 %add.a.0, %b.0.add
+  br i1 %cmp, label %while.body, label %while.end
+
+while.end:                                        ; preds = %while.body
+  ret i32 0
+}
+
+declare i32 @rand()
+
+declare void @llvm.dbg.value(metadata, metadata, metadata)
+
+attributes #0 = { "target-cpu"="x86-64" }
+
+!llvm.dbg.cu = !{!0}
+!llvm.module.flags = !{!3, !4}
+
+!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0 (trunk)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
+!1 = !DIFile(filename: "PR34565.c", directory: "\5C")
+!2 = !{}
+!3 = !{i32 2, !"Dwarf Version", i32 4}
+!4 = !{i32 2, !"Debug Info Version", i32 3}
+!5 = distinct !DISubprogram(name: "main", scope: !1, file: !1, line: 3, type: !6, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, unit: !0, variables: !9)
+!6 = !DISubroutineType(types: !7)
+!7 = !{!8}
+!8 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+!9 = !{!10, !12}
+!10 = !DILocalVariable(name: "a", scope: !5, file: !1, line: 6, type: !11)
+!11 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned)
+!12 = !DILocalVariable(name: "b", scope: !5, file: !1, line: 7, type: !11)
+!13 = !DILocation(line: 6, column: 16, scope: !5)
+!14 = !DILocation(line: 7, column: 16, scope: !5)