llvm/test/DebugInfo/MIR/InstrRef/livedebugvalues-transfer-variadic-instr-ref.mir - rust-lang/llvm-project - Git at Google

 # RUN: llc %s -o - -experimental-debug-variable-locations=true \
 # RUN:     -run-pass=livedebugvalues  | \
 # RUN: FileCheck %s --implicit-check-not=DBG_VALUE
 #
 ## Check that LiveDebugValues can track and join DBG_INSTR_REFs that use
 ## registers, stack slots, and constants in a single instruction.
 #
 # CHECK: ![[VAR_D:[0-9]+]] = !DILocalVariable(name: "d"

 # CHECK-LABEL: bb.0.entry
 #
 ## Value at end of first block should use the registers given by DBG_PHI, and
 ## fold the offset+deref from stack slot [$rsp+12] into the expression.
 # CHECK:       DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $ebp, $rsp, $ebx, 6

 # CHECK-LABEL: bb.1.while.body
 #
 ## Prior DBG_VALUE_LIST should be live-in to this bb.1.
 # CHECK:       DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $ebp, $rsp, $ebx, 6
 #
 ## When $ebp is spilled to a stack slot, a new debug value using the stack slot
 ## should be inserted.
 # CHECK:       MOV32mr $rsp, {{.+}} $ebp
 # CHECK-NEXT:  DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_plus_uconst, 16, DW_OP_deref, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $rsp, $rsp, $ebx, 6
 #
 ## Similarly produce a new debug value when $ebx is spilled.
 # CHECK:       MOV32mr $rsp, {{.+}} $ebx
 # CHECK-NEXT:  DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_plus_uconst, 16, DW_OP_deref, DW_OP_LLVM_arg, 2, DW_OP_plus_uconst, 20, DW_OP_deref, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $rsp, $rsp, $rsp, 6
 #
 ## When the value in the stack slot is restored and then that slot is clobbered, the debug value should use the restored register.
 # CHECK:       MOV32mi $rsp
 # CHECK-NEXT:  DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_plus_uconst, 16, DW_OP_deref, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $rsp, $rsp, $ebx, 6
 #
 ## Repeat for the next stack slot that gets restored and then clobbered.
 # CHECK:       MOV32mi $rsp
 # CHECK-NEXT:  DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $ebp, $rsp, $ebx, 6
 #
 ## TODO: The debug value range should be terminated when the value in $ebx is clobbered.
 #
 ## At the end of the block a new DBG_INSTR_REF begins a new range.
 # CHECK:       DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $ebp, $rsp, $ebx, 6

 # CHECK-LABEL: bb.2.while.end
 #
 ## Finally, the two entry debug values should be joined, as they have identical
 ## expressions, their respective stack slots and constants are identical, and
 ## the remaining operands occupy the same registers out of each block.
 # CHECK:       DBG_VALUE_LIST ![[VAR_D]]
 # CHECK-SAME:  !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
 # CHECK-SAME:  $ebp, $rsp, $ebx, 6


 --- |

   ; ModuleID = 'test.ll'
   source_filename = "test.cpp"
   target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
   target triple = "x86_64-unknown-linux-gnu"

   ; Function Attrs: mustprogress uwtable
   define dso_local noundef i32 @_Z3fooii(i32 noundef %a, i32 noundef %b) local_unnamed_addr !dbg !9 {
   entry:
     %call = tail call noundef i32 @_Z3bazv(), !dbg !18
     call void @llvm.dbg.value(metadata !DIArgList(i32 %a, i32 %call, i32 %b), metadata !17, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_constu, 6, DW_OP_minus, DW_OP_stack_value)), !dbg !19
     %cmp19 = icmp sgt i32 %b, %a, !dbg !20
     br i1 %cmp19, label %while.body.preheader, label %while.end, !dbg !21

   while.body.preheader:                             ; preds = %entry
     br label %while.body, !dbg !21

   while.body:                                       ; preds = %while.body.preheader, %while.body
     %a.addr.021 = phi i32 [ %mul3, %while.body ], [ %a, %while.body.preheader ]
     %b.addr.020 = phi i32 [ %add2, %while.body ], [ %b, %while.body.preheader ]
     %call1 = tail call noundef i32 @_Z3bazv(), !dbg !22
     tail call void asm sideeffect "", "~{rax},~{rbx},~{rcx},~{rdx},~{rsi},~{rdi},~{rbp},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"() #3, !dbg !24, !srcloc !25
     %add2 = add i32 %b.addr.020, 2, !dbg !26
     %mul3 = shl nsw i32 %a.addr.021, 1, !dbg !27
     call void @llvm.dbg.value(metadata !DIArgList(i32 %mul3, i32 %call, i32 %add2), metadata !17, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_constu, 6, DW_OP_minus, DW_OP_stack_value)), !dbg !19
     %cmp = icmp sgt i32 %add2, %mul3, !dbg !20
     br i1 %cmp, label %while.body, label %while.end, !dbg !21, !llvm.loop !28

   while.end:                                        ; preds = %while.body, %entry
     %b.addr.0.lcssa = phi i32 [ %b, %entry ], [ %add2, %while.body ]
     %a.addr.0.lcssa = phi i32 [ %a, %entry ], [ %mul3, %while.body ]
     %add7 = sub i32 %b.addr.0.lcssa, %call, !dbg !31
     %sub8 = add i32 %add7, %a.addr.0.lcssa, !dbg !32
     ret i32 %sub8, !dbg !33
   }

   declare !dbg !34 noundef i32 @_Z3bazv() local_unnamed_addr

   ; Function Attrs: nocallback nofree nosync nounwind readnone speculatable willreturn
   declare void @llvm.dbg.value(metadata, metadata, metadata)

   !llvm.dbg.cu = !{!0}
   !llvm.module.flags = !{!2, !3, !4, !5, !6, !7}
   !llvm.ident = !{!8}

   !0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 16.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: None)
   !1 = !DIFile(filename: "test.cpp", directory: "/")
   !2 = !{i32 7, !"Dwarf Version", i32 5}
   !3 = !{i32 2, !"Debug Info Version", i32 3}
   !4 = !{i32 1, !"wchar_size", i32 4}
   !5 = !{i32 8, !"PIC Level", i32 2}
   !6 = !{i32 7, !"PIE Level", i32 2}
   !7 = !{i32 7, !"uwtable", i32 2}
   !8 = !{!"clang version 16.0.0"}
   !9 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooii", scope: !1, file: !1, line: 3, type: !10, scopeLine: 3, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !13)
   !10 = !DISubroutineType(types: !11)
   !11 = !{!12, !12, !12}
   !12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
   !13 = !{!14, !15, !16, !17}
   !14 = !DILocalVariable(name: "a", arg: 1, scope: !9, file: !1, line: 3, type: !12)
   !15 = !DILocalVariable(name: "b", arg: 2, scope: !9, file: !1, line: 3, type: !12)
   !16 = !DILocalVariable(name: "c", scope: !9, file: !1, line: 4, type: !12)
   !17 = !DILocalVariable(name: "d", scope: !9, file: !1, line: 5, type: !12)
   !18 = !DILocation(line: 4, column: 11, scope: !9)
   !19 = !DILocation(line: 0, scope: !9)
   !20 = !DILocation(line: 6, column: 12, scope: !9)
   !21 = !DILocation(line: 6, column: 3, scope: !9)
   !22 = !DILocation(line: 7, column: 5, scope: !23)
   !23 = distinct !DILexicalBlock(scope: !9, file: !1, line: 6, column: 17)
   !24 = !DILocation(line: 9, column: 5, scope: !23)
   !25 = !{i64 129}
   !26 = !DILocation(line: 8, column: 7, scope: !23)
   !27 = !DILocation(line: 10, column: 7, scope: !23)
   !28 = distinct !{!28, !21, !29, !30}
   !29 = !DILocation(line: 12, column: 3, scope: !9)
   !30 = !{!"llvm.loop.mustprogress"}
   !31 = !DILocation(line: 13, column: 12, scope: !9)
   !32 = !DILocation(line: 13, column: 16, scope: !9)
   !33 = !DILocation(line: 13, column: 3, scope: !9)
   !34 = !DISubprogram(name: "baz", linkageName: "_Z3bazv", scope: !1, file: !1, line: 1, type: !35, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !37)
   !35 = !DISubroutineType(types: !36)
   !36 = !{!12}
   !37 = !{}

 ...
 ---
 name:            _Z3fooii
 alignment:       16
 tracksRegLiveness: true
 tracksDebugUserValues: true
 debugInstrRef: true
 registers:       []
 liveins:
   - { reg: '$edi', virtual-reg: '' }
   - { reg: '$esi', virtual-reg: '' }
 frameInfo:
   stackSize:       72
   offsetAdjustment: -72
   maxAlignment:    4
   adjustsStack:    true
   hasCalls:        true
   stackProtector:  ''
   functionContext: ''
   cvBytesOfCalleeSavedRegisters: 48
   savePoint:       ''
   restorePoint:    ''
 fixedStack:
   - { id: 0, type: spill-slot, offset: -56, size: 8, alignment: 8, stack-id: default,
       callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
       debug-info-expression: '', debug-info-location: '' }
   - { id: 1, type: spill-slot, offset: -48, size: 8, alignment: 16, stack-id: default,
       callee-saved-register: '$r12', callee-saved-restored: true, debug-info-variable: '',
       debug-info-expression: '', debug-info-location: '' }
   - { id: 2, type: spill-slot, offset: -40, size: 8, alignment: 8, stack-id: default,
       callee-saved-register: '$r13', callee-saved-restored: true, debug-info-variable: '',
       debug-info-expression: '', debug-info-location: '' }
   - { id: 3, type: spill-slot, offset: -32, size: 8, alignment: 16, stack-id: default,
       callee-saved-register: '$r14', callee-saved-restored: true, debug-info-variable: '',
       debug-info-expression: '', debug-info-location: '' }
   - { id: 4, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default,
       callee-saved-register: '$r15', callee-saved-restored: true, debug-info-variable: '',
       debug-info-expression: '', debug-info-location: '' }
   - { id: 5, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
       callee-saved-register: '$rbp', callee-saved-restored: true, debug-info-variable: '',
       debug-info-expression: '', debug-info-location: '' }
 stack:
   - { id: 0, name: '', type: spill-slot, offset: -60, size: 4, alignment: 4,
       stack-id: default, callee-saved-register: '', callee-saved-restored: true,
       debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
   - { id: 1, name: '', type: spill-slot, offset: -64, size: 4, alignment: 4,
       stack-id: default, callee-saved-register: '', callee-saved-restored: true,
       debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
   - { id: 2, name: '', type: spill-slot, offset: -68, size: 4, alignment: 4,
       stack-id: default, callee-saved-register: '', callee-saved-restored: true,
       debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
 callSites:       []
 debugValueSubstitutions: []
 constants:       []
 machineFunctionInfo: {}
 body:             |
   bb.0.entry:
     successors: %bb.1(0x78e38e39), %bb.3(0x071c71c7)
     liveins: $edi, $esi, $rbp, $r15, $r14, $r13, $r12, $rbx

     frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp
     frame-setup CFI_INSTRUCTION def_cfa_offset 16
     frame-setup PUSH64r killed $r15, implicit-def $rsp, implicit $rsp
     frame-setup CFI_INSTRUCTION def_cfa_offset 24
     frame-setup PUSH64r killed $r14, implicit-def $rsp, implicit $rsp
     frame-setup CFI_INSTRUCTION def_cfa_offset 32
     frame-setup PUSH64r killed $r13, implicit-def $rsp, implicit $rsp
     frame-setup CFI_INSTRUCTION def_cfa_offset 40
     frame-setup PUSH64r killed $r12, implicit-def $rsp, implicit $rsp
     frame-setup CFI_INSTRUCTION def_cfa_offset 48
     frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
     frame-setup CFI_INSTRUCTION def_cfa_offset 56
     $rsp = frame-setup SUB64ri8 $rsp, 24, implicit-def dead $eflags
     frame-setup CFI_INSTRUCTION def_cfa_offset 80
     CFI_INSTRUCTION offset $rbx, -56
     CFI_INSTRUCTION offset $r12, -48
     CFI_INSTRUCTION offset $r13, -40
     CFI_INSTRUCTION offset $r14, -32
     CFI_INSTRUCTION offset $r15, -24
     CFI_INSTRUCTION offset $rbp, -16
     DBG_PHI $esi, 5
     DBG_PHI $edi, 3
     $ebx = MOV32rr $esi
     $ebp = MOV32rr $edi
     CALL64pcrel32 target-flags(x86-plt) @_Z3bazv, csr_64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-instr-number 4, debug-location !18
     MOV32mr $rsp, 1, $noreg, 12, $noreg, $eax :: (store (s32) into %stack.2)
     DBG_INSTR_REF !17, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value), dbg-instr-ref(3, 0), dbg-instr-ref(4, 6), dbg-instr-ref(5, 0), 6, debug-location !19
     CMP32rr renamable $ebx, renamable $ebp, implicit-def $eflags, debug-location !20
     JCC_1 %bb.3, 14, implicit $eflags, debug-location !21

   bb.1.while.body (align 16):
     successors: %bb.1(0x78e38e39), %bb.3(0x071c71c7)
     liveins: $ebp, $ebx

     MOV32mr $rsp, 1, $noreg, 16, $noreg, killed renamable $ebp :: (store (s32) into %stack.1)
     MOV32mr $rsp, 1, $noreg, 20, $noreg, killed renamable $ebx :: (store (s32) into %stack.0)
     CALL64pcrel32 target-flags(x86-plt) @_Z3bazv, csr_64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp, implicit-def dead $eax, debug-location !22
     INLINEASM &"", 1 /* sideeffect attdialect */, 12 /* clobber */, implicit-def dead early-clobber $rax, 12 /* clobber */, implicit-def dead early-clobber $rbx, 12 /* clobber */, implicit-def dead early-clobber $rcx, 12 /* clobber */, implicit-def dead early-clobber $rdx, 12 /* clobber */, implicit-def dead early-clobber $rsi, 12 /* clobber */, implicit-def dead early-clobber $rdi, 12 /* clobber */, implicit-def dead early-clobber $rbp, 12 /* clobber */, implicit-def dead early-clobber $r8, 12 /* clobber */, implicit-def dead early-clobber $r9, 12 /* clobber */, implicit-def dead early-clobber $r10, 12 /* clobber */, implicit-def dead early-clobber $r11, 12 /* clobber */, implicit-def dead early-clobber $r12, 12 /* clobber */, implicit-def dead early-clobber $r13, 12 /* clobber */, implicit-def dead early-clobber $r14, 12 /* clobber */, implicit-def dead early-clobber $r15, 12 /* clobber */, implicit-def dead early-clobber $df, 12 /* clobber */, implicit-def early-clobber $fpsw, 12 /* clobber */, implicit-def dead early-clobber $eflags, !25, debug-location !24
     renamable $ebp = MOV32rm $rsp, 1, $noreg, 16, $noreg :: (load (s32) from %stack.1)
     renamable $ebx = MOV32rm $rsp, 1, $noreg, 20, $noreg :: (load (s32) from %stack.0)
     MOV32mi $rsp, 1, $noreg, 20, $noreg, 0 :: (store (s32) into %stack.0)
     MOV32mi $rsp, 1, $noreg, 16, $noreg, 0 :: (store (s32) into %stack.1)
     renamable $ebx = ADD32ri8 killed renamable $ebx, 2, implicit-def dead $eflags, debug-instr-number 2, debug-location !26
     renamable $ebp = nsw ADD32rr killed renamable $ebp, renamable $ebp, implicit-def dead $eflags, debug-instr-number 1, debug-location !27
     DBG_INSTR_REF !17, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value), dbg-instr-ref(1, 0), dbg-instr-ref(4, 6), dbg-instr-ref(2, 0), 6, debug-location !19
     CMP32rr renamable $ebx, renamable $ebp, implicit-def $eflags, debug-location !20
     JCC_1 %bb.1, 15, implicit $eflags, debug-location !21

   bb.3.while.end:
     liveins: $ebp, $ebx

     renamable $ebx = SUB32rm killed renamable $ebx, $rsp, 1, $noreg, 12, $noreg, implicit-def dead $eflags, debug-location !31 :: (load (s32) from %stack.2)
     renamable $ebx = ADD32rr killed renamable $ebx, killed renamable $ebp, implicit-def dead $eflags, debug-location !32
     $eax = MOV32rr killed $ebx, debug-location !33
     $rsp = frame-destroy ADD64ri8 $rsp, 24, implicit-def dead $eflags, debug-location !33
     frame-destroy CFI_INSTRUCTION def_cfa_offset 56, debug-location !33
     $rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
     frame-destroy CFI_INSTRUCTION def_cfa_offset 48, debug-location !33
     $r12 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
     frame-destroy CFI_INSTRUCTION def_cfa_offset 40, debug-location !33
     $r13 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
     frame-destroy CFI_INSTRUCTION def_cfa_offset 32, debug-location !33
     $r14 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
     frame-destroy CFI_INSTRUCTION def_cfa_offset 24, debug-location !33
     $r15 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
     frame-destroy CFI_INSTRUCTION def_cfa_offset 16, debug-location !33
     $rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
     frame-destroy CFI_INSTRUCTION def_cfa_offset 8, debug-location !33
     RET64 $eax, debug-location !33

 ...
	# RUN: llc %s -o - -experimental-debug-variable-locations=true \
	# RUN: -run-pass=livedebugvalues \| \
	# RUN: FileCheck %s --implicit-check-not=DBG_VALUE
	#
	## Check that LiveDebugValues can track and join DBG_INSTR_REFs that use
	## registers, stack slots, and constants in a single instruction.
	#
	# CHECK: ![[VAR_D:[0-9]+]] = !DILocalVariable(name: "d"

	# CHECK-LABEL: bb.0.entry
	#
	## Value at end of first block should use the registers given by DBG_PHI, and
	## fold the offset+deref from stack slot [$rsp+12] into the expression.
	# CHECK: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $ebp, $rsp, $ebx, 6

	# CHECK-LABEL: bb.1.while.body
	#
	## Prior DBG_VALUE_LIST should be live-in to this bb.1.
	# CHECK: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $ebp, $rsp, $ebx, 6
	#
	## When $ebp is spilled to a stack slot, a new debug value using the stack slot
	## should be inserted.
	# CHECK: MOV32mr $rsp, {{.+}} $ebp
	# CHECK-NEXT: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_plus_uconst, 16, DW_OP_deref, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $rsp, $rsp, $ebx, 6
	#
	## Similarly produce a new debug value when $ebx is spilled.
	# CHECK: MOV32mr $rsp, {{.+}} $ebx
	# CHECK-NEXT: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_plus_uconst, 16, DW_OP_deref, DW_OP_LLVM_arg, 2, DW_OP_plus_uconst, 20, DW_OP_deref, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $rsp, $rsp, $rsp, 6
	#
	## When the value in the stack slot is restored and then that slot is clobbered, the debug value should use the restored register.
	# CHECK: MOV32mi $rsp
	# CHECK-NEXT: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_plus_uconst, 16, DW_OP_deref, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $rsp, $rsp, $ebx, 6
	#
	## Repeat for the next stack slot that gets restored and then clobbered.
	# CHECK: MOV32mi $rsp
	# CHECK-NEXT: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $ebp, $rsp, $ebx, 6
	#
	## TODO: The debug value range should be terminated when the value in $ebx is clobbered.
	#
	## At the end of the block a new DBG_INSTR_REF begins a new range.
	# CHECK: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $ebp, $rsp, $ebx, 6

	# CHECK-LABEL: bb.2.while.end
	#
	## Finally, the two entry debug values should be joined, as they have identical
	## expressions, their respective stack slots and constants are identical, and
	## the remaining operands occupy the same registers out of each block.
	# CHECK: DBG_VALUE_LIST ![[VAR_D]]
	# CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus_uconst, 12, DW_OP_deref, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value)
	# CHECK-SAME: $ebp, $rsp, $ebx, 6


	--- \|

	; ModuleID = 'test.ll'
	source_filename = "test.cpp"
	target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"
	target triple = "x86_64-unknown-linux-gnu"

	; Function Attrs: mustprogress uwtable
	define dso_local noundef i32 @_Z3fooii(i32 noundef %a, i32 noundef %b) local_unnamed_addr !dbg !9 {
	entry:
	%call = tail call noundef i32 @_Z3bazv(), !dbg !18
	call void @llvm.dbg.value(metadata !DIArgList(i32 %a, i32 %call, i32 %b), metadata !17, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_constu, 6, DW_OP_minus, DW_OP_stack_value)), !dbg !19
	%cmp19 = icmp sgt i32 %b, %a, !dbg !20
	br i1 %cmp19, label %while.body.preheader, label %while.end, !dbg !21

	while.body.preheader: ; preds = %entry
	br label %while.body, !dbg !21

	while.body: ; preds = %while.body.preheader, %while.body
	%a.addr.021 = phi i32 [ %mul3, %while.body ], [ %a, %while.body.preheader ]
	%b.addr.020 = phi i32 [ %add2, %while.body ], [ %b, %while.body.preheader ]
	%call1 = tail call noundef i32 @_Z3bazv(), !dbg !22
	tail call void asm sideeffect "", "~{rax},~{rbx},~{rcx},~{rdx},~{rsi},~{rdi},~{rbp},~{r8},~{r9},~{r10},~{r11},~{r12},~{r13},~{r14},~{r15},~{dirflag},~{fpsr},~{flags}"() #3, !dbg !24, !srcloc !25
	%add2 = add i32 %b.addr.020, 2, !dbg !26
	%mul3 = shl nsw i32 %a.addr.021, 1, !dbg !27
	call void @llvm.dbg.value(metadata !DIArgList(i32 %mul3, i32 %call, i32 %add2), metadata !17, metadata !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_constu, 6, DW_OP_minus, DW_OP_stack_value)), !dbg !19
	%cmp = icmp sgt i32 %add2, %mul3, !dbg !20
	br i1 %cmp, label %while.body, label %while.end, !dbg !21, !llvm.loop !28

	while.end: ; preds = %while.body, %entry
	%b.addr.0.lcssa = phi i32 [ %b, %entry ], [ %add2, %while.body ]
	%a.addr.0.lcssa = phi i32 [ %a, %entry ], [ %mul3, %while.body ]
	%add7 = sub i32 %b.addr.0.lcssa, %call, !dbg !31
	%sub8 = add i32 %add7, %a.addr.0.lcssa, !dbg !32
	ret i32 %sub8, !dbg !33
	}

	declare !dbg !34 noundef i32 @_Z3bazv() local_unnamed_addr

	; Function Attrs: nocallback nofree nosync nounwind readnone speculatable willreturn
	declare void @llvm.dbg.value(metadata, metadata, metadata)

	!llvm.dbg.cu = !{!0}
	!llvm.module.flags = !{!2, !3, !4, !5, !6, !7}
	!llvm.ident = !{!8}

	!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus_14, file: !1, producer: "clang version 16.0.0", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, splitDebugInlining: false, nameTableKind: None)
	!1 = !DIFile(filename: "test.cpp", directory: "/")
	!2 = !{i32 7, !"Dwarf Version", i32 5}
	!3 = !{i32 2, !"Debug Info Version", i32 3}
	!4 = !{i32 1, !"wchar_size", i32 4}
	!5 = !{i32 8, !"PIC Level", i32 2}
	!6 = !{i32 7, !"PIE Level", i32 2}
	!7 = !{i32 7, !"uwtable", i32 2}
	!8 = !{!"clang version 16.0.0"}
	!9 = distinct !DISubprogram(name: "foo", linkageName: "_Z3fooii", scope: !1, file: !1, line: 3, type: !10, scopeLine: 3, flags: DIFlagPrototyped \| DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition \| DISPFlagOptimized, unit: !0, retainedNodes: !13)
	!10 = !DISubroutineType(types: !11)
	!11 = !{!12, !12, !12}
	!12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
	!13 = !{!14, !15, !16, !17}
	!14 = !DILocalVariable(name: "a", arg: 1, scope: !9, file: !1, line: 3, type: !12)
	!15 = !DILocalVariable(name: "b", arg: 2, scope: !9, file: !1, line: 3, type: !12)
	!16 = !DILocalVariable(name: "c", scope: !9, file: !1, line: 4, type: !12)
	!17 = !DILocalVariable(name: "d", scope: !9, file: !1, line: 5, type: !12)
	!18 = !DILocation(line: 4, column: 11, scope: !9)
	!19 = !DILocation(line: 0, scope: !9)
	!20 = !DILocation(line: 6, column: 12, scope: !9)
	!21 = !DILocation(line: 6, column: 3, scope: !9)
	!22 = !DILocation(line: 7, column: 5, scope: !23)
	!23 = distinct !DILexicalBlock(scope: !9, file: !1, line: 6, column: 17)
	!24 = !DILocation(line: 9, column: 5, scope: !23)
	!25 = !{i64 129}
	!26 = !DILocation(line: 8, column: 7, scope: !23)
	!27 = !DILocation(line: 10, column: 7, scope: !23)
	!28 = distinct !{!28, !21, !29, !30}
	!29 = !DILocation(line: 12, column: 3, scope: !9)
	!30 = !{!"llvm.loop.mustprogress"}
	!31 = !DILocation(line: 13, column: 12, scope: !9)
	!32 = !DILocation(line: 13, column: 16, scope: !9)
	!33 = !DILocation(line: 13, column: 3, scope: !9)
	!34 = !DISubprogram(name: "baz", linkageName: "_Z3bazv", scope: !1, file: !1, line: 1, type: !35, flags: DIFlagPrototyped, spFlags: DISPFlagOptimized, retainedNodes: !37)
	!35 = !DISubroutineType(types: !36)
	!36 = !{!12}
	!37 = !{}

	...
	---
	name: _Z3fooii
	alignment: 16
	tracksRegLiveness: true
	tracksDebugUserValues: true
	debugInstrRef: true
	registers: []
	liveins:
	- { reg: '$edi', virtual-reg: '' }
	- { reg: '$esi', virtual-reg: '' }
	frameInfo:
	stackSize: 72
	offsetAdjustment: -72
	maxAlignment: 4
	adjustsStack: true
	hasCalls: true
	stackProtector: ''
	functionContext: ''
	cvBytesOfCalleeSavedRegisters: 48
	savePoint: ''
	restorePoint: ''
	fixedStack:
	- { id: 0, type: spill-slot, offset: -56, size: 8, alignment: 8, stack-id: default,
	callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
	debug-info-expression: '', debug-info-location: '' }
	- { id: 1, type: spill-slot, offset: -48, size: 8, alignment: 16, stack-id: default,
	callee-saved-register: '$r12', callee-saved-restored: true, debug-info-variable: '',
	debug-info-expression: '', debug-info-location: '' }
	- { id: 2, type: spill-slot, offset: -40, size: 8, alignment: 8, stack-id: default,
	callee-saved-register: '$r13', callee-saved-restored: true, debug-info-variable: '',
	debug-info-expression: '', debug-info-location: '' }
	- { id: 3, type: spill-slot, offset: -32, size: 8, alignment: 16, stack-id: default,
	callee-saved-register: '$r14', callee-saved-restored: true, debug-info-variable: '',
	debug-info-expression: '', debug-info-location: '' }
	- { id: 4, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default,
	callee-saved-register: '$r15', callee-saved-restored: true, debug-info-variable: '',
	debug-info-expression: '', debug-info-location: '' }
	- { id: 5, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
	callee-saved-register: '$rbp', callee-saved-restored: true, debug-info-variable: '',
	debug-info-expression: '', debug-info-location: '' }
	stack:
	- { id: 0, name: '', type: spill-slot, offset: -60, size: 4, alignment: 4,
	stack-id: default, callee-saved-register: '', callee-saved-restored: true,
	debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
	- { id: 1, name: '', type: spill-slot, offset: -64, size: 4, alignment: 4,
	stack-id: default, callee-saved-register: '', callee-saved-restored: true,
	debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
	- { id: 2, name: '', type: spill-slot, offset: -68, size: 4, alignment: 4,
	stack-id: default, callee-saved-register: '', callee-saved-restored: true,
	debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
	callSites: []
	debugValueSubstitutions: []
	constants: []
	machineFunctionInfo: {}
	body: \|
	bb.0.entry:
	successors: %bb.1(0x78e38e39), %bb.3(0x071c71c7)
	liveins: $edi, $esi, $rbp, $r15, $r14, $r13, $r12, $rbx

	frame-setup PUSH64r killed $rbp, implicit-def $rsp, implicit $rsp
	frame-setup CFI_INSTRUCTION def_cfa_offset 16
	frame-setup PUSH64r killed $r15, implicit-def $rsp, implicit $rsp
	frame-setup CFI_INSTRUCTION def_cfa_offset 24
	frame-setup PUSH64r killed $r14, implicit-def $rsp, implicit $rsp
	frame-setup CFI_INSTRUCTION def_cfa_offset 32
	frame-setup PUSH64r killed $r13, implicit-def $rsp, implicit $rsp
	frame-setup CFI_INSTRUCTION def_cfa_offset 40
	frame-setup PUSH64r killed $r12, implicit-def $rsp, implicit $rsp
	frame-setup CFI_INSTRUCTION def_cfa_offset 48
	frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
	frame-setup CFI_INSTRUCTION def_cfa_offset 56
	$rsp = frame-setup SUB64ri8 $rsp, 24, implicit-def dead $eflags
	frame-setup CFI_INSTRUCTION def_cfa_offset 80
	CFI_INSTRUCTION offset $rbx, -56
	CFI_INSTRUCTION offset $r12, -48
	CFI_INSTRUCTION offset $r13, -40
	CFI_INSTRUCTION offset $r14, -32
	CFI_INSTRUCTION offset $r15, -24
	CFI_INSTRUCTION offset $rbp, -16
	DBG_PHI $esi, 5
	DBG_PHI $edi, 3
	$ebx = MOV32rr $esi
	$ebp = MOV32rr $edi
	CALL64pcrel32 target-flags(x86-plt) @_Z3bazv, csr_64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-instr-number 4, debug-location !18
	MOV32mr $rsp, 1, $noreg, 12, $noreg, $eax :: (store (s32) into %stack.2)
	DBG_INSTR_REF !17, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value), dbg-instr-ref(3, 0), dbg-instr-ref(4, 6), dbg-instr-ref(5, 0), 6, debug-location !19
	CMP32rr renamable $ebx, renamable $ebp, implicit-def $eflags, debug-location !20
	JCC_1 %bb.3, 14, implicit $eflags, debug-location !21

	bb.1.while.body (align 16):
	successors: %bb.1(0x78e38e39), %bb.3(0x071c71c7)
	liveins: $ebp, $ebx

	MOV32mr $rsp, 1, $noreg, 16, $noreg, killed renamable $ebp :: (store (s32) into %stack.1)
	MOV32mr $rsp, 1, $noreg, 20, $noreg, killed renamable $ebx :: (store (s32) into %stack.0)
	CALL64pcrel32 target-flags(x86-plt) @_Z3bazv, csr_64, implicit $rsp, implicit $ssp, implicit-def $rsp, implicit-def $ssp, implicit-def dead $eax, debug-location !22
	INLINEASM &"", 1 /* sideeffect attdialect /, 12 / clobber /, implicit-def dead early-clobber $rax, 12 / clobber /, implicit-def dead early-clobber $rbx, 12 / clobber /, implicit-def dead early-clobber $rcx, 12 / clobber /, implicit-def dead early-clobber $rdx, 12 / clobber /, implicit-def dead early-clobber $rsi, 12 / clobber /, implicit-def dead early-clobber $rdi, 12 / clobber /, implicit-def dead early-clobber $rbp, 12 / clobber /, implicit-def dead early-clobber $r8, 12 / clobber /, implicit-def dead early-clobber $r9, 12 / clobber /, implicit-def dead early-clobber $r10, 12 / clobber /, implicit-def dead early-clobber $r11, 12 / clobber /, implicit-def dead early-clobber $r12, 12 / clobber /, implicit-def dead early-clobber $r13, 12 / clobber /, implicit-def dead early-clobber $r14, 12 / clobber /, implicit-def dead early-clobber $r15, 12 / clobber /, implicit-def dead early-clobber $df, 12 / clobber /, implicit-def early-clobber $fpsw, 12 / clobber */, implicit-def dead early-clobber $eflags, !25, debug-location !24
	renamable $ebp = MOV32rm $rsp, 1, $noreg, 16, $noreg :: (load (s32) from %stack.1)
	renamable $ebx = MOV32rm $rsp, 1, $noreg, 20, $noreg :: (load (s32) from %stack.0)
	MOV32mi $rsp, 1, $noreg, 20, $noreg, 0 :: (store (s32) into %stack.0)
	MOV32mi $rsp, 1, $noreg, 16, $noreg, 0 :: (store (s32) into %stack.1)
	renamable $ebx = ADD32ri8 killed renamable $ebx, 2, implicit-def dead $eflags, debug-instr-number 2, debug-location !26
	renamable $ebp = nsw ADD32rr killed renamable $ebp, renamable $ebp, implicit-def dead $eflags, debug-instr-number 1, debug-location !27
	DBG_INSTR_REF !17, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_arg, 2, DW_OP_mul, DW_OP_LLVM_arg, 1, DW_OP_plus, DW_OP_LLVM_arg, 3, DW_OP_minus, DW_OP_stack_value), dbg-instr-ref(1, 0), dbg-instr-ref(4, 6), dbg-instr-ref(2, 0), 6, debug-location !19
	CMP32rr renamable $ebx, renamable $ebp, implicit-def $eflags, debug-location !20
	JCC_1 %bb.1, 15, implicit $eflags, debug-location !21

	bb.3.while.end:
	liveins: $ebp, $ebx

	renamable $ebx = SUB32rm killed renamable $ebx, $rsp, 1, $noreg, 12, $noreg, implicit-def dead $eflags, debug-location !31 :: (load (s32) from %stack.2)
	renamable $ebx = ADD32rr killed renamable $ebx, killed renamable $ebp, implicit-def dead $eflags, debug-location !32
	$eax = MOV32rr killed $ebx, debug-location !33
	$rsp = frame-destroy ADD64ri8 $rsp, 24, implicit-def dead $eflags, debug-location !33
	frame-destroy CFI_INSTRUCTION def_cfa_offset 56, debug-location !33
	$rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
	frame-destroy CFI_INSTRUCTION def_cfa_offset 48, debug-location !33
	$r12 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
	frame-destroy CFI_INSTRUCTION def_cfa_offset 40, debug-location !33
	$r13 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
	frame-destroy CFI_INSTRUCTION def_cfa_offset 32, debug-location !33
	$r14 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
	frame-destroy CFI_INSTRUCTION def_cfa_offset 24, debug-location !33
	$r15 = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
	frame-destroy CFI_INSTRUCTION def_cfa_offset 16, debug-location !33
	$rbp = frame-destroy POP64r implicit-def $rsp, implicit $rsp, debug-location !33
	frame-destroy CFI_INSTRUCTION def_cfa_offset 8, debug-location !33
	RET64 $eax, debug-location !33

	...