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|
# RUN: llc -start-after=machine-scheduler %s -o - | FileCheck %s
# C source:
# void escape(int *);
# extern int global;
# void f(int x) {
# escape(&x);
# x = 1;
# global = x;
# x = 2;
# escape(&x);
# }
# CHECK-LABEL: f: # @f
# CHECK: movl %ecx, [[OFF_X:[0-9]+]](%rsp)
# CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]]] [$rsp+0]
# CHECK: leaq [[OFF_X]](%rsp), %rsi
# CHECK: callq escape
# CHECK: #DEBUG_VALUE: f:x <- 1
# CHECK: movl $1, global(%rip)
# CHECK: #DEBUG_VALUE: f:x <- [DW_OP_plus_uconst [[OFF_X]]] [$rsp+0]
# CHECK: movl $2, [[OFF_X]](%rsp)
# CHECK: callq escape
# CHECK: retq
--- |
; ModuleID = '<stdin>'
source_filename = "dse.c"
target datalayout = "e-m:w-i64:64-f80:128-n8:16:32:64-S128"
target triple = "x86_64-pc-windows-msvc19.0.24215"
@global = external global i32, align 4
; Function Attrs: nounwind readnone speculatable
declare void @llvm.dbg.value(metadata, metadata, metadata) #0
declare void @escape(i32*)
; Function Attrs: nounwind uwtable
define void @f(i32 %x) #1 !dbg !8 {
entry:
%x.addr = alloca i32, align 4
store i32 %x, i32* %x.addr, align 4
call void @llvm.dbg.value(metadata i32* %x.addr, metadata !13, metadata !DIExpression()), !dbg !14
call void @escape(i32* %x.addr), !dbg !15
call void @llvm.dbg.value(metadata i32 1, metadata !13, metadata !DIExpression()), !dbg !16
store i32 1, i32* @global, align 4, !dbg !17
call void @llvm.dbg.value(metadata i32* %x.addr, metadata !13, metadata !DIExpression()), !dbg !18
store i32 2, i32* %x.addr, align 4, !dbg !18
call void @escape(i32* %x.addr), !dbg !19
ret void, !dbg !20
}
; Function Attrs: nounwind
declare void @llvm.stackprotector(i8*, i8**) #2
attributes #0 = { nounwind readnone speculatable }
attributes #1 = { nounwind uwtable }
attributes #2 = { nounwind }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4, !5, !6}
!llvm.ident = !{!7}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "clang version 6.0.0 ", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2)
!1 = !DIFile(filename: "dse.c", directory: "C:\5Csrc\5Cllvm-project\5Cbuild")
!2 = !{}
!3 = !{i32 2, !"Dwarf Version", i32 4}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = !{i32 1, !"wchar_size", i32 2}
!6 = !{i32 7, !"PIC Level", i32 2}
!7 = !{!"clang version 6.0.0 "}
!8 = distinct !DISubprogram(name: "f", scope: !1, file: !1, line: 3, type: !9, isLocal: false, isDefinition: true, scopeLine: 3, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !12)
!9 = !DISubroutineType(types: !10)
!10 = !{null, !11}
!11 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!12 = !{!13}
!13 = !DILocalVariable(name: "x", arg: 1, scope: !8, file: !1, line: 3, type: !11)
!14 = !DILocation(line: 3, column: 12, scope: !8)
!15 = !DILocation(line: 4, column: 3, scope: !8)
!16 = !DILocation(line: 5, column: 5, scope: !8)
!17 = !DILocation(line: 6, column: 10, scope: !8)
!18 = !DILocation(line: 7, column: 5, scope: !8)
!19 = !DILocation(line: 8, column: 3, scope: !8)
!20 = !DILocation(line: 9, column: 1, scope: !8)
...
---
name: f
alignment: 16
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
tracksRegLiveness: true
registers:
- { id: 0, class: gr32, preferred-register: '' }
- { id: 1, class: gr64, preferred-register: '' }
liveins:
- { reg: '$ecx', virtual-reg: '%0' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 0
offsetAdjustment: 0
maxAlignment: 8
adjustsStack: false
hasCalls: true
stackProtector: ''
maxCallFrameSize: 4294967295
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
savePoint: ''
restorePoint: ''
fixedStack:
stack:
- { id: 0, name: x.addr, type: default, offset: 0, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
constants:
body: |
bb.0.entry:
liveins: $ecx
%0 = COPY $ecx
MOV32mr %stack.0.x.addr, 1, _, 0, _, %0 :: (store 4 into %ir.x.addr)
DBG_VALUE %stack.0.x.addr, 0, !13, !DIExpression(), debug-location !14
ADJCALLSTACKDOWN64 32, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !15
%1 = LEA64r %stack.0.x.addr, 1, _, 0, _
$rcx = COPY %1, debug-location !15
CALL64pcrel32 @escape, csr_win64, implicit $rsp, implicit $ssp, implicit $rcx, implicit-def $rsp, implicit-def $ssp, debug-location !15
ADJCALLSTACKUP64 32, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !15
DBG_VALUE 1, _, !13, !DIExpression(), debug-location !16
MOV32mi $rip, 1, _, @global, _, 1, debug-location !17 :: (store 4 into @global)
DBG_VALUE %stack.0.x.addr, 0, !13, !DIExpression(), debug-location !18
MOV32mi %stack.0.x.addr, 1, _, 0, _, 2, debug-location !18 :: (store 4 into %ir.x.addr)
ADJCALLSTACKDOWN64 32, 0, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !19
$rcx = COPY %1, debug-location !19
CALL64pcrel32 @escape, csr_win64, implicit $rsp, implicit $ssp, implicit $rcx, implicit-def $rsp, implicit-def $ssp, debug-location !19
ADJCALLSTACKUP64 32, 0, implicit-def dead $rsp, implicit-def dead $eflags, implicit-def dead $ssp, implicit $rsp, implicit $ssp, debug-location !19
RET 0, debug-location !20
...
|
