# RUN: llc -o - %s -start-after=patchable-function -O0 -mtriple=x86_64-unknown-linux-gnu | FileCheck %s
# Test dwarf codegen of DW_OP_minus.
#
# This was built by compiling the following source with SafeStack and
# simplifying the result a little.
# extern "C" {
# void Capture(int *);
# void f() {
# int buf[100];
# Capture(buf);
# }
# }
# The interesting part is !DIExpression(DW_OP_constu, 400, DW_OP_minus)
#
# RCX - 400
# CHECK: .short 3 # Loc expr size
# CHECK-NEXT: .byte 114 # DW_OP_breg2
# CHECK-NEXT: .byte 240 # -400
# CHECK-NEXT: .byte 124
#
# RCX is clobbered in call @Capture, but there is a spilled copy.
# *(RSP + 8) - 400
# CHECK: .short 7 # Loc expr size
# CHECK-NEXT: .byte 119 # DW_OP_breg7
# CHECK-NEXT: .byte 8 # 8
# CHECK-NEXT: .byte 6 # DW_OP_deref
# CHECK-NEXT: .byte 16 # DW_OP_constu
# CHECK-NEXT: .byte 144 # 400
# CHECK-NEXT: .byte 3 #
# CHECK-NEXT: .byte 28 # DW_OP_minus
--- |
@__safestack_unsafe_stack_ptr = external thread_local(initialexec) global ptr
define void @f() !dbg !5 {
entry:
%unsafe_stack_ptr = load ptr, ptr @__safestack_unsafe_stack_ptr
%unsafe_stack_static_top = getelementptr i8, ptr %unsafe_stack_ptr, i32 -400
store ptr %unsafe_stack_static_top, ptr @__safestack_unsafe_stack_ptr
%0 = getelementptr i8, ptr %unsafe_stack_ptr, i32 -400
%buf = bitcast ptr %0 to ptr
%1 = bitcast ptr %buf to ptr, !dbg !14
call void @llvm.dbg.declare(metadata ptr %unsafe_stack_ptr, metadata !9, metadata !DIExpression(DW_OP_constu, 400, DW_OP_minus)), !dbg !15
%arraydecay = getelementptr inbounds [100 x i32], ptr %buf, i64 0, i64 0, !dbg !16
call void @Capture(ptr %arraydecay), !dbg !17
store ptr %unsafe_stack_ptr, ptr @__safestack_unsafe_stack_ptr, !dbg !18
ret void, !dbg !18
}
; Function Attrs: nounwind readnone speculatable
declare void @llvm.dbg.declare(metadata, metadata, metadata) #0
declare void @Capture(ptr)
; Function Attrs: nounwind
declare void @llvm.stackprotector(ptr, ptr) #1
attributes #0 = { nounwind readnone speculatable }
attributes #1 = { nounwind }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4}
!0 = distinct !DICompileUnit(language: DW_LANG_C_plus_plus, file: !1, producer: "clang version 3.8.0 (trunk 248518) (llvm/trunk 248512)", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
!1 = !DIFile(filename: "1.cc", directory: "/tmp")
!2 = !{}
!3 = !{i32 2, !"Dwarf Version", i32 4}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 4, type: !6, isLocal: false, isDefinition: true, scopeLine: 4, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !8)
!6 = !DISubroutineType(types: !7)
!7 = !{null}
!8 = !{!9}
!9 = !DILocalVariable(name: "buf", scope: !5, file: !1, line: 5, type: !10)
!10 = !DICompositeType(tag: DW_TAG_array_type, baseType: !11, size: 3200, align: 32, elements: !12)
!11 = !DIBasicType(name: "int", size: 32, align: 32, encoding: DW_ATE_signed)
!12 = !{!13}
!13 = !DISubrange(count: 100)
!14 = !DILocation(line: 5, column: 3, scope: !5)
!15 = !DILocation(line: 5, column: 7, scope: !5)
!16 = !DILocation(line: 6, column: 11, scope: !5)
!17 = !DILocation(line: 6, column: 3, scope: !5)
!18 = !DILocation(line: 7, column: 1, scope: !5)
...
---
name: f
alignment: 16
tracksRegLiveness: true
frameInfo:
stackSize: 24
maxAlignment: 8
adjustsStack: true
hasCalls: true
maxCallFrameSize: 0
stack:
- { id: 0, type: spill-slot, offset: -16, size: 8, alignment: 8, stack-id: default }
- { id: 1, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default }
body: |
bb.0.entry:
$rsp = frame-setup SUB64ri8 $rsp, 24, implicit-def dead $eflags
CFI_INSTRUCTION def_cfa_offset 32
renamable $rax = MOV64rm $rip, 1, $noreg, target-flags(x86-gottpoff) @__safestack_unsafe_stack_ptr, $noreg :: (load (s64) from got)
renamable $rcx = MOV64rm renamable $rax, 1, $noreg, 0, $fs :: (dereferenceable load (s64) from @__safestack_unsafe_stack_ptr)
DBG_VALUE renamable $rcx, 0, !9, !DIExpression(DW_OP_constu, 400, DW_OP_minus), debug-location !15
$rdx = MOV64rr $rcx
renamable $rdx = ADD64ri32 renamable $rdx, -400, implicit-def dead $eflags
MOV64mr renamable $rax, 1, $noreg, 0, $fs, renamable $rdx :: (store (s64) into @__safestack_unsafe_stack_ptr)
$rdi = MOV64rr killed $rdx, debug-location !17
MOV64mr $rsp, 1, $noreg, 16, $noreg, killed $rax :: (store (s64) into %stack.0)
MOV64mr $rsp, 1, $noreg, 8, $noreg, killed $rcx :: (store (s64) into %stack.1)
DBG_VALUE $rsp, 0, !9, !DIExpression(DW_OP_plus_uconst, 8, DW_OP_deref, DW_OP_constu, 400, DW_OP_minus), debug-location !15
CALL64pcrel32 @Capture, csr_64, implicit $rsp, implicit $ssp, implicit killed $rdi, implicit-def $rsp, implicit-def $ssp, debug-location !17
$rax = MOV64rm $rsp, 1, $noreg, 16, $noreg :: (load (s64) from %stack.0)
$rcx = MOV64rm $rsp, 1, $noreg, 8, $noreg :: (load (s64) from %stack.1)
MOV64mr killed renamable $rax, 1, $noreg, 0, $fs, killed renamable $rcx, debug-location !18 :: (store (s64) into @__safestack_unsafe_stack_ptr)
$rsp = frame-destroy ADD64ri8 $rsp, 24, implicit-def dead $eflags, debug-location !18
CFI_INSTRUCTION def_cfa_offset 8, debug-location !18
RET64 debug-location !18
...
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