Index: include/llvm/CodeGen/TargetInstrInfo.h
===================================================================
--- include/llvm/CodeGen/TargetInstrInfo.h
+++ include/llvm/CodeGen/TargetInstrInfo.h
@@ -944,6 +944,17 @@
     return isCopyInstrImpl(MI, Source, Destination);
   }
 
+  /// If the specific machine instruction is an instruction that adds an
+  /// immediate value to its \c Source operand and stores it in \c Destination,
+  /// return true along with \c Destination and \c Source machine operand to
+  /// which \c Offset has been added.
+  virtual bool isAddImmediate(const MachineInstr &MI,
+                              const MachineOperand *&Destination,
+                              const MachineOperand *&Source,
+                              int &Offset) const {
+    return false;
+  }
+
   /// Store the specified register of the given register class to the specified
   /// stack frame index. The store instruction is to be added to the given
   /// machine basic block before the specified machine instruction. If isKill
Index: lib/CodeGen/AsmPrinter/DwarfDebug.cpp
===================================================================
--- lib/CodeGen/AsmPrinter/DwarfDebug.cpp
+++ lib/CodeGen/AsmPrinter/DwarfDebug.cpp
@@ -642,15 +642,20 @@
     // least partially) defined by the instruction's single explicit define.
     if (I->getNumExplicitDefs() != 1 || ExplicitFwdRegDefs.empty())
       continue;
-    unsigned Reg = ExplicitFwdRegDefs[0];
+    unsigned ParamFwdReg = ExplicitFwdRegDefs[0];
 
     if (auto ParamValue = TII->describeLoadedValue(*I)) {
       if (ParamValue->first.isImm()) {
         int64_t Val = ParamValue->first.getImm();
         DbgValueLoc DbgLocVal(ParamValue->second, Val);
-        finishCallSiteParam(DbgLocVal, Reg);
+        finishCallSiteParam(DbgLocVal, ParamFwdReg);
       } else if (ParamValue->first.isReg()) {
         Register RegLoc = ParamValue->first.getReg();
+       // TODO: For now, there is no use of describing the value loaded into the
+       //       register that is also the source registers (e.g. $r0 = add $r0, x).
+       if (ParamFwdReg == RegLoc)
+         continue;
+
         unsigned SP = TLI->getStackPointerRegisterToSaveRestore();
         Register FP = TRI->getFrameRegister(*MF);
         bool IsSPorFP = (RegLoc == SP) || (RegLoc == FP);
@@ -658,10 +663,12 @@
           DbgValueLoc DbgLocVal(ParamValue->second,
                                 MachineLocation(RegLoc,
                                                 /*IsIndirect=*/IsSPorFP));
-          finishCallSiteParam(DbgLocVal, Reg);
-        } else if (ShouldTryEmitEntryVals) {
+          finishCallSiteParam(DbgLocVal, ParamFwdReg);
+        // TODO: Add support for entry value plus an expression.
+        } else if (ShouldTryEmitEntryVals &&
+                   ParamValue->second->getNumElements() == 0) {
           ForwardedRegWorklist.insert(RegLoc);
-          RegsForEntryValues[RegLoc] = Reg;
+          RegsForEntryValues[RegLoc] = ParamFwdReg;
         }
       }
     }
Index: lib/CodeGen/TargetInstrInfo.cpp
===================================================================
--- lib/CodeGen/TargetInstrInfo.cpp
+++ lib/CodeGen/TargetInstrInfo.cpp
@@ -1124,15 +1124,18 @@
 TargetInstrInfo::describeLoadedValue(const MachineInstr &MI) const {
   const MachineFunction *MF = MI.getMF();
   const MachineOperand *Op = nullptr;
-  DIExpression *Expr = DIExpression::get(MF->getFunction().getContext(), {});;
+  DIExpression *Expr = DIExpression::get(MF->getFunction().getContext(), {});
   const MachineOperand *SrcRegOp, *DestRegOp;
+  int Offset;
 
   if (isCopyInstr(MI, SrcRegOp, DestRegOp)) {
-    Op = SrcRegOp;
-    return ParamLoadedValue(*Op, Expr);
+    return ParamLoadedValue(*SrcRegOp, Expr);
   } else if (MI.isMoveImmediate()) {
     Op = &MI.getOperand(1);
     return ParamLoadedValue(*Op, Expr);
+  } else if (isAddImmediate(MI, DestRegOp, SrcRegOp, Offset)) {
+    Expr = DIExpression::prepend(Expr, DIExpression::ApplyOffset, Offset);
+    return ParamLoadedValue(*SrcRegOp, Expr);
   }
 
   return None;
Index: lib/Target/AArch64/AArch64InstrInfo.h
===================================================================
--- lib/Target/AArch64/AArch64InstrInfo.h
+++ lib/Target/AArch64/AArch64InstrInfo.h
@@ -265,6 +265,14 @@
   /// on Windows.
   static bool isSEHInstruction(const MachineInstr &MI);
 
+  bool isAddImmediate(const MachineInstr &MI,
+                      const MachineOperand *&Destination,
+                      const MachineOperand *&Source,
+                      int &Offset) const override;
+
+  Optional<ParamLoadedValue>
+  describeLoadedValue(const MachineInstr &MI) const override;
+
 #define GET_INSTRINFO_HELPER_DECLS
 #include "AArch64GenInstrInfo.inc"
 
Index: lib/Target/AArch64/AArch64InstrInfo.cpp
===================================================================
--- lib/Target/AArch64/AArch64InstrInfo.cpp
+++ lib/Target/AArch64/AArch64InstrInfo.cpp
@@ -5727,5 +5727,53 @@
   return false;
 }
 
+bool AArch64InstrInfo::isAddImmediate(const MachineInstr &MI,
+                                      const MachineOperand *&Destination,
+                                      const MachineOperand *&Source,
+                                      int &Offset) const {
+  int Sign = 1;
+  switch (MI.getOpcode()) {
+  default:
+    return false;
+  case AArch64::SUBWri:
+  case AArch64::SUBXri:
+  case AArch64::SUBSWri:
+  case AArch64::SUBSXri:
+    Sign *= -1;
+    LLVM_FALLTHROUGH;
+  case AArch64::ADDSWri:
+  case AArch64::ADDSXri:
+  case AArch64::ADDWri:
+  case AArch64::ADDXri: {
+    // TODO: Third operand can be global address (usually some string).
+    if (!MI.getOperand(0).isReg() || !MI.getOperand(1).isReg() ||
+        !MI.getOperand(2).isImm())
+      return false;
+    Source = &MI.getOperand(1);
+    Offset = MI.getOperand(2).getImm() * Sign;
+    int Shift = MI.getOperand(3).getImm();
+    assert((Shift == 0 || Shift == 12) && "Shift can be either 0 or 12");
+    Offset = Offset << Shift;
+  }
+  }
+  Destination = &MI.getOperand(0);
+  return true;
+}
+
+Optional<ParamLoadedValue>
+AArch64InstrInfo::describeLoadedValue(const MachineInstr &MI) const {
+  switch (MI.getOpcode()) {
+  case AArch64::MOVZWi:
+  case AArch64::MOVZXi:
+    if (!MI.getOperand(1).isImm())
+      return None;
+    int Immediate = MI.getOperand(1).getImm();
+    int Shift = MI.getOperand(2).getImm();
+    return ParamLoadedValue(MachineOperand::CreateImm(Immediate << Shift),
+                            nullptr);
+  }
+  return TargetInstrInfo::describeLoadedValue(MI);
+}
+
 #define GET_INSTRINFO_HELPERS
 #include "AArch64GenInstrInfo.inc"
Index: lib/Target/ARM/ARMBaseInstrInfo.h
===================================================================
--- lib/Target/ARM/ARMBaseInstrInfo.h
+++ lib/Target/ARM/ARMBaseInstrInfo.h
@@ -455,6 +455,11 @@
     // 3 - predicate reg
     return MI.getOperand(3).getReg();
   }
+
+  bool isAddImmediate(const MachineInstr &MI,
+                      const MachineOperand *&Destination,
+                      const MachineOperand *&Source,
+                      int &Offset) const override;
 };
 
 /// Get the operands corresponding to the given \p Pred value. By default, the
Index: lib/Target/ARM/ARMBaseInstrInfo.cpp
===================================================================
--- lib/Target/ARM/ARMBaseInstrInfo.cpp
+++ lib/Target/ARM/ARMBaseInstrInfo.cpp
@@ -5350,6 +5350,32 @@
   return makeArrayRef(TargetFlags);
 }
 
+bool ARMBaseInstrInfo::isAddImmediate(const MachineInstr &MI,
+                                      const MachineOperand *&Destination,
+                                      const MachineOperand *&Source,
+                                      int &Offset) const {
+  int Sign = 1;
+  unsigned Opcode = MI.getOpcode();
+
+  // We describe SUBri or ADDri instructions.
+  if (Opcode == ARM::SUBri)
+    Sign = -1;
+  else if (Opcode != ARM::ADDri)
+    return false;
+
+  // TODO: Third operand can be global address (usually some string). Since
+  //       strings can be relocated we cannot calculate their offsets for
+  //       now.
+  if (!MI.getOperand(0).isReg() || !MI.getOperand(1).isReg() ||
+      !MI.getOperand(2).isImm())
+    return false;
+
+  Destination = &MI.getOperand(0);
+  Source = &MI.getOperand(1);
+  Offset = MI.getOperand(2).getImm() * Sign;
+  return true;
+}
+
 bool llvm::registerDefinedBetween(unsigned Reg,
                                   MachineBasicBlock::iterator From,
                                   MachineBasicBlock::iterator To,
Index: test/DebugInfo/MIR/AArch64/dbgcall-site-interpretation.mir
===================================================================
--- /dev/null
+++ test/DebugInfo/MIR/AArch64/dbgcall-site-interpretation.mir
@@ -0,0 +1,180 @@
+# RUN: llc -mtriple aarch64-linux-gnu -debug-entry-values -start-after=machineverifier -filetype=obj %s -o -| llvm-dwarfdump -| FileCheck %s
+# Following code is used for producing this test case. Note that
+# some of argument loading instruction are modified in order to
+# cover certain cases.
+#
+# extern int func2(int,int,int*);
+# int func1(int arg1, int arg2, int arg3) {
+#   int a = func2(arg1 + 2, arg2 - 4, &arg3);
+#   a += func2(arg3 - 16, arg1 + 8, &a);
+#   return a++;
+# }
+#
+# CHECK: DW_TAG_GNU_call_site
+# CHECK-NEXT: DW_AT_abstract_origin {{.*}} "func2"
+# CHECK: DW_TAG_GNU_call_site_parameter
+# CHECK-NOT:   DW_AT_location      (DW_OP_reg2 W0)
+# CHECK-NEXT:   DW_AT_location      (DW_OP_reg2 W2)
+# CHECK-NEXT:   DW_AT_GNU_call_site_value   (DW_OP_fbreg +28)
+# CHECK-EMPTY: 
+# CHECK-NEXT: DW_TAG_GNU_call_site_parameter
+# CHECK-NEXT:   DW_AT_location      (DW_OP_reg1 W1)
+# CHECK-NEXT:   DW_AT_GNU_call_site_value   (DW_OP_breg19 W19-4)
+# CHECK: DW_TAG_GNU_call_site
+# CHECK-NEXT: DW_AT_abstract_origin {{.*}} "func2")
+# CHECK-NEXT: DW_AT_low_pc
+# CHECK-EMPTY: 
+# CHECK-NEXT: DW_TAG_GNU_call_site_parameter
+# CHECK-NEXT:   DW_AT_location      (DW_OP_reg0 W0)
+# CHECK-NEXT:   DW_AT_GNU_call_site_value   (DW_OP_lit13)
+# CHECK-EMPTY: 
+# CHECK-NEXT: DW_TAG_GNU_call_site_parameter
+# W2 loads memory location. We can't rely that memory location won't be changed.
+# CHECK-NOT:   DW_AT_location      (DW_OP_reg2 W2)
+# CHECK-NEXT:   DW_AT_location      (DW_OP_reg1 W1)
+# CHECK-NEXT:   DW_AT_GNU_call_site_value   (DW_OP_constu 0xc0)
+--- |
+  ; ModuleID = 'describe-call-pram-load-instruction.c'
+  source_filename = "describe-call-pram-load-instruction.c"
+  target datalayout = "e-m:e-i8:8:32-i16:16:32-i64:64-i128:128-n32:64-S128"
+  target triple = "aarch64-unknown-linux-gnu"
+  
+  ; Function Attrs: nounwind
+  define dso_local i32 @func1(i32 %arg1, i32 %arg2, i32 %arg3) local_unnamed_addr #0 !dbg !13 {
+  entry:
+    %arg3.addr = alloca i32, align 4
+    %a = alloca i32, align 4
+    call void @llvm.dbg.value(metadata i32 %arg1, metadata !17, metadata !DIExpression()), !dbg !21
+    call void @llvm.dbg.value(metadata i32 %arg2, metadata !18, metadata !DIExpression()), !dbg !21
+    call void @llvm.dbg.value(metadata i32 %arg3, metadata !19, metadata !DIExpression()), !dbg !21
+    store i32 %arg3, i32* %arg3.addr, align 4
+    %0 = bitcast i32* %a to i8*, !dbg !21
+    call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull %0), !dbg !21
+    %add = add nsw i32 %arg1, 2, !dbg !21
+    %sub = add nsw i32 %arg2, -4, !dbg !21
+    call void @llvm.dbg.value(metadata i32* %arg3.addr, metadata !19, metadata !DIExpression(DW_OP_deref)), !dbg !21
+    %call = call i32 @func2(i32 %add, i32 %sub, i32* nonnull %arg3.addr), !dbg !21
+    call void @llvm.dbg.value(metadata i32 %call, metadata !20, metadata !DIExpression()), !dbg !21
+    store i32 %call, i32* %a, align 4, !dbg !21
+    %1 = load i32, i32* %arg3.addr, align 4, !dbg !21
+    call void @llvm.dbg.value(metadata i32 %1, metadata !19, metadata !DIExpression()), !dbg !21
+    %sub1 = add nsw i32 %1, -16, !dbg !21
+    %add2 = add nsw i32 %arg1, 8, !dbg !21
+    call void @llvm.dbg.value(metadata i32* %a, metadata !20, metadata !DIExpression(DW_OP_deref)), !dbg !21
+    %call3 = call i32 @func2(i32 %sub1, i32 %add2, i32* nonnull %a), !dbg !21
+    %2 = load i32, i32* %a, align 4, !dbg !21
+    call void @llvm.dbg.value(metadata i32 %2, metadata !20, metadata !DIExpression()), !dbg !21
+    %add4 = add nsw i32 %2, %call3, !dbg !21
+    call void @llvm.dbg.value(metadata i32 %add4, metadata !20, metadata !DIExpression(DW_OP_plus_uconst, 1, DW_OP_stack_value)), !dbg !21
+    call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull %0), !dbg !21
+    ret i32 %add4, !dbg !21
+  }
+  
+  ; Function Attrs: argmemonly nounwind willreturn
+  declare void @llvm.lifetime.start.p0i8(i64 immarg, i8* nocapture)
+  
+  declare !dbg !4 dso_local i32 @func2(i32, i32, i32*) local_unnamed_addr
+  
+  ; Function Attrs: argmemonly nounwind willreturn
+  declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture)
+  
+  ; Function Attrs: nounwind readnone speculatable willreturn
+  declare void @llvm.dbg.value(metadata, metadata, metadata)
+  
+  ; Function Attrs: nounwind
+  declare void @llvm.stackprotector(i8*, i8**)
+  
+  attributes #0 = { "frame-pointer"="all" }
+  
+  !llvm.dbg.cu = !{!0}
+  !llvm.module.flags = !{!9, !10, !11}
+  !llvm.ident = !{!12}
+  
+  !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
+  !1 = !DIFile(filename: "describe-call-pram-load-instruction.c", directory: "/")
+  !2 = !{}
+  !3 = !{!4}
+  !4 = !DISubprogram(name: "func2", scope: !1, file: !1, line: 8, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
+  !5 = !DISubroutineType(types: !6)
+  !6 = !{!7, !7, !7, !8}
+  !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+  !8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !7, size: 64)
+  !9 = !{i32 2, !"Dwarf Version", i32 4}
+  !10 = !{i32 2, !"Debug Info Version", i32 3}
+  !11 = !{i32 1, !"wchar_size", i32 4}
+  !12 = !{!"clang version 10.0.0 "}
+  !13 = distinct !DISubprogram(name: "func1", scope: !1, file: !1, line: 9, type: !14, scopeLine: 9, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !16)
+  !14 = !DISubroutineType(types: !15)
+  !15 = !{!7, !7, !7, !7}
+  !16 = !{!17, !18, !19, !20}
+  !17 = !DILocalVariable(name: "arg1", arg: 1, scope: !13, file: !1, line: 9, type: !7, flags: DIFlagArgumentNotModified)
+  !18 = !DILocalVariable(name: "arg2", arg: 2, scope: !13, file: !1, line: 9, type: !7, flags: DIFlagArgumentNotModified)
+  !19 = !DILocalVariable(name: "arg3", arg: 3, scope: !13, file: !1, line: 9, type: !7)
+  !20 = !DILocalVariable(name: "a", scope: !13, file: !1, line: 10, type: !7)
+  !21 = !DILocation(line: 0, scope: !13)
+
+...
+---
+name:            func1
+frameInfo:
+  adjustsStack:    true
+  hasCalls:        true
+stack:
+  - { id: 0, name: arg3.addr, offset: -4, size: 4, alignment: 4, local-offset: -4 }
+  - { id: 1, name: a, offset: -8, size: 4, alignment: 4, local-offset: -8 }
+  - { id: 2, type: spill-slot, offset: -16, size: 8, alignment: 16, callee-saved-register: '$x19' }
+  - { id: 3, type: spill-slot, offset: -24, size: 8, alignment: 8, callee-saved-register: '$lr' }
+  - { id: 4, type: spill-slot, offset: -32, size: 8, alignment: 8, callee-saved-register: '$fp' }
+callSites:
+  - { bb: 0, offset: 20, fwdArgRegs: 
+      - { arg: 0, reg: '$w0' }
+      - { arg: 1, reg: '$w1' }
+      - { arg: 2, reg: '$x2' } }
+  - { bb: 0, offset: 29, fwdArgRegs: 
+      - { arg: 0, reg: '$w0' }
+      - { arg: 1, reg: '$w1' }
+      - { arg: 2, reg: '$x2' } }
+body:             |
+  bb.0.entry:
+    liveins: $w0, $w1, $w2, $lr, $x19
+  
+    DBG_VALUE $w0, $noreg, !17, !DIExpression(), debug-location !21
+    DBG_VALUE $w1, $noreg, !18, !DIExpression(), debug-location !21
+    DBG_VALUE $w1, $noreg, !18, !DIExpression(), debug-location !21
+    DBG_VALUE $w2, $noreg, !19, !DIExpression(), debug-location !21
+    DBG_VALUE $w2, $noreg, !19, !DIExpression(), debug-location !21
+    early-clobber $sp = frame-setup STPXpre $fp, killed $lr, $sp, -4 :: (store 8 into %stack.4), (store 8 into %stack.3)
+    frame-setup STRXui killed $x19, $sp, 2 :: (store 8 into %stack.2)
+    $fp = frame-setup ADDXri $sp, 0, 0
+    frame-setup CFI_INSTRUCTION def_cfa $w29, 32
+    frame-setup CFI_INSTRUCTION offset $w19, -16
+    frame-setup CFI_INSTRUCTION offset $w30, -24
+    frame-setup CFI_INSTRUCTION offset $w29, -32
+    $w19 = ORRWrs $wzr, $w0, 0
+    DBG_VALUE $w19, $noreg, !17, !DIExpression(), debug-location !21
+    STRWui killed renamable $w2, $fp, 7 :: (store 4 into %ir.arg3.addr)
+    renamable $w0 = nsw ADDWri $w0, 2, 0, debug-location !21
+    renamable $w1 = nsw SUBWri renamable $w19, 4, 0, debug-location !21
+    DBG_VALUE $w1, $noreg, !18, !DIExpression(DW_OP_LLVM_entry_value, 1), debug-location !21
+    DBG_VALUE $fp, $noreg, !19, !DIExpression(DW_OP_plus_uconst, 28, DW_OP_deref), debug-location !21
+    $x2 = ADDXri $fp, 28, 0, debug-location !21
+    BL @func2, csr_aarch64_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $w0, implicit killed $w1, implicit killed $x2, implicit-def $sp, implicit-def $w0, debug-location !21
+    DBG_VALUE $w0, $noreg, !20, !DIExpression(), debug-location !21
+    renamable $w8 = LDRWui $fp, 7, debug-location !21 :: (dereferenceable load 4 from %ir.arg3.addr)
+    DBG_VALUE $w8, $noreg, !19, !DIExpression(), debug-location !21
+    STRWui killed renamable $w0, $fp, 6, debug-location !21 :: (store 4 into %ir.a)
+    renamable $w1 = nsw MOVZWi 12, 4
+    DBG_VALUE $fp, $noreg, !20, !DIExpression(DW_OP_plus_uconst, 24, DW_OP_deref), debug-location !21
+    $x2 = LDRXui $fp, 24, debug-location !21
+    renamable $w0 = nsw MOVZWi 13, 0
+    BL @func2, csr_aarch64_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $w0, implicit killed $w1, implicit killed $x2, implicit-def $sp, implicit-def $w0, debug-location !21
+    renamable $w8 = LDRWui $fp, 6, debug-location !21 :: (dereferenceable load 4 from %ir.a)
+    DBG_VALUE $w8, $noreg, !20, !DIExpression(), debug-location !21
+    $x19 = frame-destroy LDRXui $sp, 2, debug-location !21 :: (load 8 from %stack.2)
+    DBG_VALUE $w0, $noreg, !17, !DIExpression(DW_OP_LLVM_entry_value, 1), debug-location !21
+    $w0 = ADDWrs killed renamable $w8, killed renamable $w0, 0, debug-location !21
+    DBG_VALUE $w0, $noreg, !20, !DIExpression(DW_OP_plus_uconst, 1, DW_OP_stack_value), debug-location !21
+    early-clobber $sp, $fp, $lr = frame-destroy LDPXpost $sp, 4, debug-location !21 :: (load 8 from %stack.4), (load 8 from %stack.3)
+    RET undef $lr, implicit killed $w0, debug-location !21
+
+...
Index: test/DebugInfo/MIR/ARM/dbgcall-site-interpretation.mir
===================================================================
--- /dev/null
+++ test/DebugInfo/MIR/ARM/dbgcall-site-interpretation.mir
@@ -0,0 +1,171 @@
+# RUN: llc -mtriple=arm-linux-gnueabi -debug-entry-values -filetype=obj -start-after=machineverifier %s -o -| llvm-dwarfdump -| FileCheck %s
+# Following code is used for producing this test case. Note that
+# some of argument loading instruction are modified in order to
+# cover certain cases.
+#
+# extern int func2(int,int,int*);
+# int func1(int arg1, int arg2, int arg3) {
+#   int a = func2(arg1 + 2, arg2 - 4, &arg3);
+#   a += func2(arg3 - 16, arg1 + 8, &a);
+#   return a++;
+# }
+#
+# CHECK: DW_TAG_GNU_call_site
+# CHECK-NEXT:   DW_AT_abstract_origin {{.*}}"func2")
+# CHECK-NEXT:   DW_AT_low_pc 
+# CHECK: DW_TAG_GNU_call_site_parameter
+# CHECK-NEXT:   DW_AT_location      (DW_OP_reg2 R2)
+# CHECK-NEXT:   DW_AT_GNU_call_site_value   (DW_OP_breg13 SP+4)
+# CHECK-EMPTY: 
+# CHECK-NEXT: DW_TAG_GNU_call_site_parameter
+# CHECK-NEXT:   DW_AT_location      (DW_OP_reg1 R1)
+# CHECK-NEXT:   DW_AT_GNU_call_site_value   (DW_OP_breg4 R4-4)
+# CHECK: DW_TAG_GNU_call_site
+# CHECK-NEXT:   DW_AT_abstract_origin {{.*}}"func2")
+# CHECK-NEXT:   DW_AT_low_pc 
+# CHECK-EMPTY: 
+# CHECK-NEXT: DW_TAG_GNU_call_site_parameter
+# R2 loads memory location. We can't rely that memory location won't be changed.
+# CHECK-NOT:   DW_AT_location      (DW_OP_reg2 R2)
+# CHECK-NEXT:   DW_AT_location      (DW_OP_reg1 R1)
+# CHECK-NEXT:   DW_AT_GNU_call_site_value   (DW_OP_breg4 R4+8)
+--- |
+  ; ModuleID = 'dbgcall-site-interpretation.c'
+  source_filename = "dbgcall-site-interpretation.c"
+  target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
+  target triple = "armv4t-unknown-linux-gnu"
+  
+  ; Function Attrs: nounwind
+  define dso_local arm_aapcscc i32 @func1(i32 %arg1, i32 %arg2, i32 %arg3) local_unnamed_addr #0 !dbg !14 {
+  entry:
+    %arg3.addr = alloca i32, align 4
+    %a = alloca i32, align 4
+    call void @llvm.dbg.value(metadata i32 %arg1, metadata !18, metadata !DIExpression()), !dbg !22
+    call void @llvm.dbg.value(metadata i32 %arg2, metadata !19, metadata !DIExpression()), !dbg !22
+    call void @llvm.dbg.value(metadata i32 %arg3, metadata !20, metadata !DIExpression()), !dbg !22
+    store i32 %arg3, i32* %arg3.addr, align 4
+    %0 = bitcast i32* %a to i8*, !dbg !22
+    call void @llvm.lifetime.start.p0i8(i64 4, i8* nonnull %0), !dbg !22
+    %add = add nsw i32 %arg1, 2, !dbg !22
+    %sub = add nsw i32 %arg2, -4, !dbg !22
+    call void @llvm.dbg.value(metadata i32* %arg3.addr, metadata !20, metadata !DIExpression(DW_OP_deref)), !dbg !22
+    %call = call arm_aapcscc i32 @func2(i32 %add, i32 %sub, i32* nonnull %arg3.addr), !dbg !22
+    call void @llvm.dbg.value(metadata i32 %call, metadata !21, metadata !DIExpression()), !dbg !22
+    store i32 %call, i32* %a, align 4, !dbg !22
+    %1 = load i32, i32* %arg3.addr, align 4, !dbg !22
+    call void @llvm.dbg.value(metadata i32 %1, metadata !20, metadata !DIExpression()), !dbg !22
+    %sub1 = add nsw i32 %1, -16, !dbg !22
+    %add2 = add nsw i32 %arg1, 8, !dbg !22
+    call void @llvm.dbg.value(metadata i32* %a, metadata !21, metadata !DIExpression(DW_OP_deref)), !dbg !22
+    %call3 = call arm_aapcscc i32 @func2(i32 %sub1, i32 %add2, i32* nonnull %a), !dbg !22
+    %2 = load i32, i32* %a, align 4, !dbg !22
+    call void @llvm.dbg.value(metadata i32 %2, metadata !21, metadata !DIExpression()), !dbg !22
+    %add4 = add nsw i32 %2, %call3, !dbg !22
+    call void @llvm.dbg.value(metadata i32 %add4, metadata !21, metadata !DIExpression(DW_OP_plus_uconst, 1, DW_OP_stack_value)), !dbg !22
+    call void @llvm.lifetime.end.p0i8(i64 4, i8* nonnull %0), !dbg !22
+    ret i32 %add4, !dbg !22
+  }
+  
+  ; Function Attrs: argmemonly nounwind willreturn
+  declare void @llvm.lifetime.start.p0i8(i64 immarg, i8* nocapture)
+  
+  declare !dbg !4 dso_local arm_aapcscc i32 @func2(i32, i32, i32*) local_unnamed_addr
+  
+  ; Function Attrs: argmemonly nounwind willreturn
+  declare void @llvm.lifetime.end.p0i8(i64 immarg, i8* nocapture)
+  
+  ; Function Attrs: nounwind readnone speculatable willreturn
+  declare void @llvm.dbg.value(metadata, metadata, metadata)
+  
+  ; Function Attrs: nounwind
+  declare void @llvm.stackprotector(i8*, i8**)
+  
+  attributes #0 = { "frame-pointer"="all"}
+  
+  !llvm.dbg.cu = !{!0}
+  !llvm.module.flags = !{!9, !10, !11, !12}
+  !llvm.ident = !{!13}
+  
+  !0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 10.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, retainedTypes: !3, nameTableKind: None)
+  !1 = !DIFile(filename: "dbgcall-site-interpretation.c", directory: "/")
+  !2 = !{}
+  !3 = !{!4}
+  !4 = !DISubprogram(name: "func2", scope: !1, file: !1, line: 8, type: !5, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !2)
+  !5 = !DISubroutineType(types: !6)
+  !6 = !{!7, !7, !7, !8}
+  !7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
+  !8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !7, size: 32)
+  !9 = !{i32 2, !"Dwarf Version", i32 4}
+  !10 = !{i32 2, !"Debug Info Version", i32 3}
+  !11 = !{i32 1, !"wchar_size", i32 4}
+  !12 = !{i32 1, !"min_enum_size", i32 4}
+  !13 = !{!"clang version 10.0.0"}
+  !14 = distinct !DISubprogram(name: "func1", scope: !1, file: !1, line: 9, type: !15, scopeLine: 9, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !17)
+  !15 = !DISubroutineType(types: !16)
+  !16 = !{!7, !7, !7, !7}
+  !17 = !{!18, !19, !20, !21}
+  !18 = !DILocalVariable(name: "arg1", arg: 1, scope: !14, file: !1, line: 9, type: !7, flags: DIFlagArgumentNotModified)
+  !19 = !DILocalVariable(name: "arg2", arg: 2, scope: !14, file: !1, line: 9, type: !7, flags: DIFlagArgumentNotModified)
+  !20 = !DILocalVariable(name: "arg3", arg: 3, scope: !14, file: !1, line: 9, type: !7)
+  !21 = !DILocalVariable(name: "a", scope: !14, file: !1, line: 10, type: !7)
+  !22 = !DILocation(line: 0, scope: !14)
+...
+---
+name:            func1
+alignment:       4
+callSites:
+  - { bb: 0, offset: 22, fwdArgRegs: 
+      - { arg: 0, reg: '$r0' }
+      - { arg: 1, reg: '$r1' }
+      - { arg: 2, reg: '$r2' } }
+  - { bb: 0, offset: 32, fwdArgRegs: 
+      - { arg: 0, reg: '$r0' }
+      - { arg: 1, reg: '$r1' }
+      - { arg: 2, reg: '$r2' } }
+body:             |
+  bb.0.entry:
+    liveins: $r0, $r1, $r2, $r4, $r5, $r10, $lr
+  
+    DBG_VALUE $r0, $noreg, !18, !DIExpression(), debug-location !22
+    DBG_VALUE $r1, $noreg, !19, !DIExpression(), debug-location !22
+    DBG_VALUE $r1, $noreg, !19, !DIExpression(), debug-location !22
+    DBG_VALUE $r2, $noreg, !20, !DIExpression(), debug-location !22
+    DBG_VALUE $r2, $noreg, !20, !DIExpression(), debug-location !22
+    $sp = frame-setup STMDB_UPD $sp, 14, $noreg, killed $r4, killed $r10, $r11, killed $lr
+    frame-setup CFI_INSTRUCTION def_cfa_offset 16
+    frame-setup CFI_INSTRUCTION offset $lr, -4
+    frame-setup CFI_INSTRUCTION offset $r11, -8
+    frame-setup CFI_INSTRUCTION offset $r10, -12
+    frame-setup CFI_INSTRUCTION offset $r4, -16
+    $r11 = frame-setup ADDri $sp, 8, 14, $noreg, $noreg
+    frame-setup CFI_INSTRUCTION def_cfa $r11, 8
+    $sp = frame-setup SUBri $sp, 8, 14, $noreg, $noreg
+    $r4 = MOVr $r0, 14, $noreg, $noreg
+    DBG_VALUE $r4, $noreg, !18, !DIExpression(), debug-location !22
+    STRi12 killed renamable $r2, $sp, 4, 14, $noreg :: (store 4 into %ir.arg3.addr)
+    DBG_VALUE $sp, $noreg, !20, !DIExpression(DW_OP_plus_uconst, 4, DW_OP_deref), debug-location !22
+    renamable $r0 = nsw ADDri killed $r0, 2, 14, $noreg, $noreg, debug-location !22
+    renamable $r1 = nsw SUBri renamable $r4, 4, 14, $noreg, $noreg, debug-location !22
+    DBG_VALUE $r1, $noreg, !19, !DIExpression(DW_OP_LLVM_entry_value, 1), debug-location !22
+    renamable $r2 = ADDri $sp, 4, 14, $noreg, $noreg
+    BL @func2, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit killed $r1, implicit killed $r2, implicit-def $sp, implicit-def $r0, debug-location !22
+    DBG_VALUE $r0, $noreg, !21, !DIExpression(), debug-location !22
+    STRi12 killed renamable $r0, $sp, 0, 14, $noreg, debug-location !22 :: (store 4 into %ir.a)
+    renamable $r0 = LDRi12 $sp, 4, 14, $noreg, debug-location !22 :: (dereferenceable load 4 from %ir.arg3.addr)
+    DBG_VALUE $sp, $noreg, !21, !DIExpression(DW_OP_deref), debug-location !22
+    DBG_VALUE $r0, $noreg, !20, !DIExpression(), debug-location !22
+    renamable $r1 = nsw ADDri killed renamable $r4, 8, 14, $noreg, $noreg, debug-location !22
+    $r5 = MOVr $sp, 14, $noreg, $noreg
+    renamable $r2 = LDRi12 killed $r5, 16, 14, $noreg
+    renamable $r0 = nsw SUBri killed renamable $r0, 16, 14, $noreg, $noreg, debug-location !22
+    BL @func2, csr_aapcs, implicit-def dead $lr, implicit $sp, implicit killed $r0, implicit killed $r1, implicit killed $r2, implicit-def $sp, implicit-def $r0, debug-location !22
+    renamable $r1 = LDRi12 $sp, 0, 14, $noreg, debug-location !22 :: (dereferenceable load 4 from %ir.a)
+    DBG_VALUE $r1, $noreg, !21, !DIExpression(), debug-location !22
+    renamable $r0 = nsw ADDrr killed renamable $r1, killed renamable $r0, 14, $noreg, $noreg, debug-location !22
+    DBG_VALUE $r0, $noreg, !21, !DIExpression(DW_OP_plus_uconst, 1, DW_OP_stack_value), debug-location !22
+    $sp = SUBri $r11, 8, 14, $noreg, $noreg, debug-location !22
+    $sp = LDMIA_UPD $sp, 14, $noreg, def $r4, def $r10, def $r11, def $lr, debug-location !22
+    DBG_VALUE $r0, $noreg, !18, !DIExpression(DW_OP_LLVM_entry_value, 1), debug-location !22
+    BX_RET 14, $noreg, implicit killed $r0, debug-location !22
+
+...