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1# RUN: llc %s -o - -experimental-debug-variable-locations=true \2# RUN:   -run-pass=livedebugvalues \3# RUN: | FileCheck %s --implicit-check-not=DBG_VALUE4# RUN: llc %s -o - -experimental-debug-variable-locations=true \5# RUN:   -start-before=livedebugvalues -filetype=obj \6# RUN: | llvm-dwarfdump - | FileCheck %s --check-prefix=DWARF7#8# LLVM can produce DIExpressions that convert from one value of arbitrary size9# to another. This is normally fine, however that means the value for a10# variable tracked in instruction referencing might not be the same size as the11# variable itself.12#13# This becomes a problem when values move onto the stack and we emit14# DW_OP_deref: there is no information about how large a value the consumer15# should load from the stack. The convention today appears to be the size of16# the variable, and as a result if you have a value that's smaller than the17# variable size, extra information is loaded onto the DWARF expression stack.18# This then appears as a false variable value to the consumer.19#20# In this test, there are various scenarios to test where the size of the value21# needs to reach the expression emitter in LiveDebugValues. However, there are22# even more scenarios to consider where the value is in a spill slot, and:23#  * The value is larger than the variable, the same, or smaller,24#  * The variable is a normal scalar, or a fragment,25#  * There is a DW_OP_stack_value in the expression, or not26# That gives us twelve situations to consider, and the easiest way to confirm27# correctness is to write them all out. The final DWARF expressions to28# produce are:29# * No stack value,30#   * Scalar (32 bits),31#     * Larger value (64 bits)32#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_stack_value33#     * Same value (32 bits)34#       DW_OP_breg7 RSP-835#     * Smaller value (8 bits)36#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_stack_value37#   * Fragment (32 bits)38#     * Larger value (64 bits)39#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_stack_value, DW_OP_piece 0x440#     * Same value (32 bits)41#       DW_OP_breg7 RSP-8, DW_OP_piece 0x442#     * Smaller value (8 bits)43#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_stack_value, DW_OP_piece 0x444# * Stack value (imagine there was some arithmetic on the stack before the45#   DW_OP_stack_value opcode),46#   * Scalar (32 bits),47#     * Larger value (64 bits)48#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_stack_value49#     * Same value (32 bits)50#       DW_OP_breg7 RSP-8, DW_OP_deref, DW_OP_stack_value51#     * Smaller value (8 bits)52#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_stack_value53#   * Fragment (32 bits)54#     * Larger value (64 bits)55#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_stack_value, DW_OP_piece 0x456#     * Same value (32 bits)57#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x4, DW_OP_stack_value, DW_OP_piece 0x458#     * Smaller value (8 bits)59#       DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_stack_value, DW_OP_piece 0x460#61# The outlier from the pattern is (Stack value, Fragment, Same value size): we62# put a DW_OP_deref_size in where a DW_OP_deref could have sufficied. However,63# if we used DW_OP_deref, it would force the consumer to derive the deref size64# from the DW_OP_piece, which is un-necessarily hard.65 66## Capture variable num,67# CHECK-DAG: ![[VARNUM:[0-9]+]] = !DILocalVariable(name: "flannel",68# CHECK-DAG: ![[VARNUM2:[0-9]+]] = !DILocalVariable(name: "shoes",69 70# DWARF:      DW_TAG_variable71# DWARF-NEXT: DW_AT_location72## Defined in register, spilt to stack.73# DWARF-NEXT: DW_OP_breg0 RAX+0, DW_OP_constu 0xff, DW_OP_and, DW_OP_convert (0x00000026) "DW_ATE_signed_8", DW_OP_convert (0x0000002a) "DW_ATE_signed_32", DW_OP_stack_value74# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_convert (0x00000026) "DW_ATE_signed_8", DW_OP_convert (0x0000002a) "DW_ATE_signed_32", DW_OP_stack_value75## Defined on stack.76# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_convert (0x00000026) "DW_ATE_signed_8", DW_OP_convert (0x0000002a) "DW_ATE_signed_32", DW_OP_stack_value77## DBG_PHI that moves to stack.78# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_stack_value79## DBG_PHI of stack with size.80# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x2, DW_OP_stack_value81## Followed by scalar / no-stack-value locations with various sizes.82# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_stack_value83# DWARF-NEXT: DW_OP_breg7 RSP-884# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_stack_value85## scalar / stack value with various sizes.86# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_lit1, DW_OP_plus, DW_OP_stack_value87# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref, DW_OP_lit1, DW_OP_plus, DW_OP_stack_value88# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_lit1, DW_OP_plus, DW_OP_stack_value)89# DWARF:      DW_AT_name ("flannel")90 91# Variable with fragments.92# DWARF:      DW_TAG_variable93# DWARF-NEXT: DW_AT_location94## Scalar / no-stack-value locations with various sizes.95# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_stack_value, DW_OP_piece 0x496# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_piece 0x497# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_stack_value, DW_OP_piece 0x498## Scalar / stack value with various sizes.99# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x8, DW_OP_lit1, DW_OP_plus, DW_OP_stack_value, DW_OP_piece 0x4100# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x4, DW_OP_lit1, DW_OP_plus, DW_OP_stack_value, DW_OP_piece 0x4101# DWARF-NEXT: DW_OP_breg7 RSP-8, DW_OP_deref_size 0x1, DW_OP_lit1, DW_OP_plus, DW_OP_stack_value, DW_OP_piece 0x4)102# DWARF:      DW_AT_name ("shoes")103 104--- |105  ; ModuleID = 'missingvar.ll'106  source_filename = "a"107  target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-f80:128-n8:16:32:64-S128"108  target triple = "x86_64-unknown-linux-gnu"109  110  define linkonce_odr void @_ZNSt5dequeIPN4llvm4LoopESaIS2_EE13_M_insert_auxESt15_Deque_iteratorIS2_RS2_PS2_EmRKS2_() local_unnamed_addr align 2 !dbg !3 {111  entry:112    call void @llvm.dbg.value(metadata i32 0, metadata !8, metadata !DIExpression()), !dbg !7113    call void @llvm.dbg.value(metadata i32 0, metadata !10, metadata !DIExpression()), !dbg !7114    ret void115  }116 117  declare void @llvm.dbg.value(metadata, metadata, metadata)118  119  !llvm.module.flags = !{!0, !9}120  !llvm.dbg.cu = !{!1}121  122  !0 = !{i32 2, !"Debug Info Version", i32 3}123  !1 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !2, producer: "beards", isOptimized: true, runtimeVersion: 4, emissionKind: FullDebug)124  !2 = !DIFile(filename: "bees.cpp", directory: "")125  !3 = distinct !DISubprogram(name: "nope", scope: !2, file: !2, line: 1, type: !4, spFlags: DISPFlagDefinition, unit: !1)126  !4 = !DISubroutineType(types: !5)127  !5 = !{!6}128  !6 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)129  !7 = !DILocation(line: 1, scope: !3)130  !8 = !DILocalVariable(name: "flannel", scope: !3, type: !6)131  !9 = !{i32 2, !"Dwarf Version", i32 5}132  !10 = !DILocalVariable(name: "shoes", scope: !3, type: !11)133  !11 = !DIBasicType(name: "long", size: 64, encoding: DW_ATE_signed)134 135 136...137---138name:            _ZNSt5dequeIPN4llvm4LoopESaIS2_EE13_M_insert_auxESt15_Deque_iteratorIS2_RS2_PS2_EmRKS2_139alignment:       16140tracksRegLiveness: true141debugInstrRef: true142liveins:143  - { reg: '$rdi' }144  - { reg: '$rsi' }145  - { reg: '$rdx' }146frameInfo:147  stackSize:       48148  offsetAdjustment: -48149  maxAlignment:    8150  maxCallFrameSize: 0151  cvBytesOfCalleeSavedRegisters: 48152fixedStack:153  - { id: 0, type: spill-slot, offset: -56, size: 8, alignment: 8, callee-saved-register: '$rbx' }154  - { id: 1, type: spill-slot, offset: -48, size: 8, alignment: 16, callee-saved-register: '$r12' }155  - { id: 2, type: spill-slot, offset: -40, size: 8, alignment: 8, callee-saved-register: '$r13' }156  - { id: 3, type: spill-slot, offset: -32, size: 8, alignment: 16, callee-saved-register: '$r14' }157  - { id: 4, type: spill-slot, offset: -24, size: 8, alignment: 8, callee-saved-register: '$r15' }158  - { id: 5, type: spill-slot, offset: -16, size: 8, alignment: 16, callee-saved-register: '$rbp' }159stack:160  - { id: 0, type: spill-slot, offset: -64, size: 8, alignment: 8 }161machineFunctionInfo: {}162body:             |163  bb.0.entry:164    liveins: $rdi, $rdx, $rsi, $rbp, $r15, $r14, $r13, $r12, $rbx165  166    ; CHECK-LABEL: bb.0.entry:167 168    ;; PART ONE: For this first block of tests, check that information about169    ;; the size of the value on the stack makes it through to the expression.170 171    $al = MOV8ri 0, debug-instr-number 1, debug-location !7172    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_convert, 8, DW_ATE_signed, DW_OP_LLVM_convert, 32, DW_ATE_signed, DW_OP_stack_value), dbg-instr-ref(1, 0), debug-location !7173    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],174    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_convert, 8, DW_ATE_signed,175    ; CHECK-SAME     : DW_OP_LLVM_convert, 32, DW_ATE_signed, DW_OP_stack_value), $al176 177    MOV8mr $rsp, 1, $noreg, -8, $noreg, renamable $al :: (store 1 into %stack.0)178    ;; Clobber to force variable location onto stack. We should use a179    ;; deref_size 1 because the value is smaller than the variable.180    $al = MOV8ri 0, debug-location !7181    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],182    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, 183    ; CHECK-SAME:     DW_OP_deref_size, 1, DW_OP_LLVM_convert, 8, DW_ATE_signed,184    ; CHECK-SAME:     DW_OP_LLVM_convert, 32, DW_ATE_signed, DW_OP_stack_value), $rsp185 186    ; Terminate the current variable location,187    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7188    ; CHECK: DBG_VALUE $noreg, $noreg, ![[VARNUM]], !DIExpression()189 190    ;; Try again, but with the value originating on the stack, to ensure that191    ;; we can find its size. It should be deref_size 1 again.192    INC8m $rsp, 1, $noreg, 4, $noreg, implicit-def dead $eflags, debug-instr-number 2, debug-location !7 :: (store (s8) into %stack.0)193    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_convert, 8, DW_ATE_signed, DW_OP_LLVM_convert, 32, DW_ATE_signed, DW_OP_stack_value), dbg-instr-ref(2, 1000000), debug-location !7194    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],195    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus,196    ; CHECK-SAME:     DW_OP_deref_size, 1, DW_OP_LLVM_convert, 8, DW_ATE_signed,197    ; CHECK-SAME:     DW_OP_LLVM_convert, 32, DW_ATE_signed, DW_OP_stack_value), $rsp198 199    $eax = MOV32ri 0, debug-location !7200 201    ;; How about DBG_PHIs? The size of the value is communicated by the register202    ;; size, or an extra DBG_PHI operand, and that should feed through into the203    ;; decision of whether to deref_size or not.204 205    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7206    ; CHECK: DBG_VALUE $noreg207 208    $al = MOV8ri 0, debug-location !7209    DBG_PHI $al, 7210 211    MOV32mr $rsp, 1, $noreg, -8, $noreg, renamable $eax :: (store 4 into %stack.0)212    $eax = MOV32ri 0, debug-location !7213    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0), dbg-instr-ref(7, 0), debug-location !7214    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],215    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 1, DW_OP_stack_value), $rsp216 217    $eax = MOV32ri 0, debug-location !7218 219    ;; And for when the DBG_PHI specifies a stack size...220    DBG_PHI %stack.0, 8, 16221    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0), dbg-instr-ref(8, 0), debug-location !7222    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],223    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 2, DW_OP_stack_value), $rsp224 225    $eax = MOV32ri 0, debug-location !7226    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7227    ; CHECK: DBG_VALUE $noreg, $noreg228    DBG_VALUE $noreg, $noreg, !10, !DIExpression(DW_OP_LLVM_fragment, 0, 32), debug-location !7229    ; CHECK: DBG_VALUE $noreg, $noreg230 231    ;; PART TWO: test the twelve kinds of location expression mentioned in the232    ;; opening comment of this test, in that order. Please update the opening233    ;; comment, these lines and the DWARF check lines at the same time.234    ;; In each test we'll state a location, give it an instruction to cover,235    ;; and then terminate it.236 237    ;; Scalar (32), Large value (64), no stack value,238    $rax = MOV64ri 0, debug-instr-number 10, debug-location !7239    MOV64mr $rsp, 1, $noreg, -8, $noreg, renamable $rax :: (store 8 into %stack.0)240    $rax = MOV64ri 0, debug-location !7241    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0), dbg-instr-ref(10, 0), debug-location !7242    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],243    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 8, DW_OP_stack_value), $rsp244    $eax = MOV32ri 0, debug-location !7245    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7246    ; CHECK: DBG_VALUE $noreg, $noreg247 248    ;; Scalar (32), Same value size (32), no stack value,249    $eax = MOV32ri 0, debug-instr-number 11, debug-location !7250    MOV32mr $rsp, 1, $noreg, -8, $noreg, renamable $eax :: (store 4 into %stack.0)251    $rax = MOV64ri 0, debug-location !7252    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0), dbg-instr-ref(11, 0), debug-location !7253    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],254    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref), $rsp255    $eax = MOV32ri 0, debug-location !7256    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7257    ; CHECK: DBG_VALUE $noreg, $noreg258 259    ;; Scalar (32), Smaller value (8), no stack value,260    $al = MOV8ri 0, debug-instr-number 12, debug-location !7261    MOV8mr $rsp, 1, $noreg, -8, $noreg, renamable $al :: (store 1 into %stack.0)262    $rax = MOV64ri 0, debug-location !7263    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0), dbg-instr-ref(12, 0), debug-location !7264    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],265    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 1, DW_OP_stack_value), $rsp266    $eax = MOV32ri 0, debug-location !7267    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7268    ; CHECK: DBG_VALUE $noreg, $noreg269 270    ;; Fragment (32), Larger value (64), no stack value,271    $rax = MOV64ri 0, debug-instr-number 13, debug-location !7272    MOV64mr $rsp, 1, $noreg, -8, $noreg, renamable $rax :: (store 8 into %stack.0)273    $rax = MOV64ri 0, debug-location !7274    DBG_INSTR_REF !10, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_fragment, 0, 32), dbg-instr-ref(13, 0), debug-location !7275    ; CHECK:      DBG_VALUE_LIST ![[VARNUM2]],276    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 8, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), $rsp277    $eax = MOV32ri 0, debug-location !7278    DBG_VALUE $noreg, $noreg, !10, !DIExpression(DW_OP_LLVM_fragment, 0, 32), debug-location !7279    ; CHECK: DBG_VALUE $noreg, $noreg280 281    ;; Fragment (32), Same value size (32), no stack value,282    $eax = MOV32ri 0, debug-instr-number 14, debug-location !7283    MOV32mr $rsp, 1, $noreg, -8, $noreg, renamable $eax :: (store 4 into %stack.0)284    $rax = MOV64ri 0, debug-location !7285    DBG_INSTR_REF !10, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_fragment, 0, 32), dbg-instr-ref(14, 0), debug-location !7286    ; CHECK:      DBG_VALUE_LIST ![[VARNUM2]],287    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref, DW_OP_LLVM_fragment, 0, 32), $rsp288    $eax = MOV32ri 0, debug-location !7289    DBG_VALUE $noreg, $noreg, !10, !DIExpression(DW_OP_LLVM_fragment, 0, 32), debug-location !7290    ; CHECK: DBG_VALUE $noreg, $noreg291 292    ;; Fragment (32), Smaller value (8), no stack value,293    $al = MOV8ri 0, debug-instr-number 15, debug-location !7294    MOV8mr $rsp, 1, $noreg, -8, $noreg, renamable $al :: (store 1 into %stack.0)295    $rax = MOV64ri 0, debug-location !7296    DBG_INSTR_REF !10, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_LLVM_fragment, 0, 32), dbg-instr-ref(15, 0), debug-location !7297    ; CHECK:      DBG_VALUE_LIST ![[VARNUM2]],298    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 1, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), $rsp299    $eax = MOV32ri 0, debug-location !7300    DBG_VALUE $noreg, $noreg, !10, !DIExpression(DW_OP_LLVM_fragment, 0, 32), debug-location !7301    ; CHECK: DBG_VALUE $noreg, $noreg302 303 304 305    ;; Scalar (32), Large value (64), with stack value,306    $rax = MOV64ri 0, debug-instr-number 16, debug-location !7307    MOV64mr $rsp, 1, $noreg, -8, $noreg, renamable $rax :: (store 8 into %stack.0)308    $rax = MOV64ri 0, debug-location !7309    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value), dbg-instr-ref(16, 0), debug-location !7310    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],311    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 8, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value), $rsp312    $eax = MOV32ri 0, debug-location !7313    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7314    ; CHECK: DBG_VALUE $noreg, $noreg315 316    ;; Scalar (32), Same value size (32), no stack value,317    $eax = MOV32ri 0, debug-instr-number 17, debug-location !7318    MOV32mr $rsp, 1, $noreg, -8, $noreg, renamable $eax :: (store 4 into %stack.0)319    $rax = MOV64ri 0, debug-location !7320    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value), dbg-instr-ref(17, 0), debug-location !7321    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],322    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value), $rsp323    $eax = MOV32ri 0, debug-location !7324    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7325    ; CHECK: DBG_VALUE $noreg, $noreg326 327    ;; Scalar (32), Smaller value (8), no stack value,328    $al = MOV8ri 0, debug-instr-number 18, debug-location !7329    MOV8mr $rsp, 1, $noreg, -8, $noreg, renamable $al :: (store 1 into %stack.0)330    $rax = MOV64ri 0, debug-location !7331    DBG_INSTR_REF !8, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value), dbg-instr-ref(18, 0), debug-location !7332    ; CHECK:      DBG_VALUE_LIST ![[VARNUM]],333    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 1, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value), $rsp334    $eax = MOV32ri 0, debug-location !7335    DBG_VALUE $noreg, $noreg, !8, !DIExpression(), debug-location !7336    ; CHECK: DBG_VALUE $noreg, $noreg337 338    ;; Fragment (32), Larger value (64), no stack value,339    $rax = MOV64ri 0, debug-instr-number 19, debug-location !7340    MOV64mr $rsp, 1, $noreg, -8, $noreg, renamable $rax :: (store 8 into %stack.0)341    $rax = MOV64ri 0, debug-location !7342    DBG_INSTR_REF !10, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), dbg-instr-ref(19, 0), debug-location !7343    ; CHECK:      DBG_VALUE_LIST ![[VARNUM2]],344    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 8, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), $rsp345    $eax = MOV32ri 0, debug-location !7346    DBG_VALUE $noreg, $noreg, !10, !DIExpression(DW_OP_LLVM_fragment, 0, 32), debug-location !7347    ; CHECK: DBG_VALUE $noreg, $noreg348 349    ;; Fragment (32), Same value size (32), no stack value,350    $eax = MOV32ri 0, debug-instr-number 20, debug-location !7351    MOV32mr $rsp, 1, $noreg, -8, $noreg, renamable $eax :: (store 4 into %stack.0)352    $rax = MOV64ri 0, debug-location !7353    DBG_INSTR_REF !10, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), dbg-instr-ref(20, 0), debug-location !7354    ; CHECK:      DBG_VALUE_LIST ![[VARNUM2]],355    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 4, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), $rsp356    $eax = MOV32ri 0, debug-location !7357    DBG_VALUE $noreg, $noreg, !10, !DIExpression(DW_OP_LLVM_fragment, 0, 32), debug-location !7358    ; CHECK: DBG_VALUE $noreg, $noreg359 360    ;; Fragment (32), Smaller value (8), no stack value,361    $al = MOV8ri 0, debug-instr-number 21, debug-location !7362    MOV8mr $rsp, 1, $noreg, -8, $noreg, renamable $al :: (store 1 into %stack.0)363    $rax = MOV64ri 0, debug-location !7364    DBG_INSTR_REF !10, !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), dbg-instr-ref(21, 0), debug-location !7365    ; CHECK:      DBG_VALUE_LIST ![[VARNUM2]],366    ; CHECK-SAME: !DIExpression(DW_OP_LLVM_arg, 0, DW_OP_constu, 8, DW_OP_minus, DW_OP_deref_size, 1, DW_OP_constu, 1, DW_OP_plus, DW_OP_stack_value, DW_OP_LLVM_fragment, 0, 32), $rsp367    $eax = MOV32ri 0, debug-location !7368    DBG_VALUE $noreg, $noreg, !10, !DIExpression(DW_OP_LLVM_fragment, 0, 32), debug-location !7369    ; CHECK: DBG_VALUE $noreg, $noreg370 371    RET64 0, debug-location !7372...373