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| # Generated with
#
# clang -g -O1 -S -emit-llvm test.c
# llc -stop-before=branch-folder test.ll
#
# typedef struct bar {
# int data;
# } bar;
#
# int foo(int a)
# {
# return a;
# }
#
# int baz(int *out)
# {
# int ret;
#
# if ((ret = foo(*out)) < 0)
# return ret;
# if (out)
# *out = 1;
#
# return 0;
# }
#
# int test(bar *s)
# {
# int idx, ret;
#
# retry:
# do {
# ret = baz(&idx);
# if (ret < 0)
# return ret;
# } while (idx < 0 || !s->data);
#
# goto retry;
# }
#
# RUN: llc -o - %s -mtriple=x86_64-- -run-pass=branch-folder | FileCheck %s
--- |
; ModuleID = 'test.ll'
source_filename = "test.ll"
%struct.bar = type { i32 }
define i32 @foo(i32 returned %a) local_unnamed_addr {
entry:
ret i32 %a
}
define i32 @baz(i32* %out) local_unnamed_addr !dbg !4 {
entry:
%0 = load i32, i32* %out, align 4
%call = tail call i32 @foo(i32 %0), !dbg !9
%cmp = icmp slt i32 %call, 0
br i1 %cmp, label %cleanup, label %if.then1
if.then1: ; preds = %entry
store i32 1, i32* %out, align 4
br label %cleanup
cleanup: ; preds = %if.then1, %entry
%retval.0 = phi i32 [ %call, %entry ], [ 0, %if.then1 ]
ret i32 %retval.0
}
define i32 @test(%struct.bar* nocapture readonly %s) local_unnamed_addr !dbg !11 {
entry:
%idx = alloca i32, align 4
call void @llvm.dbg.label(metadata !20), !dbg !21
%call58 = call i32 @baz(i32* nonnull %idx), !dbg !22
%cmp69 = icmp slt i32 %call58, 0
br i1 %cmp69, label %if.then, label %do.cond.lr.ph.lr.ph
do.cond.lr.ph.lr.ph: ; preds = %entry
br label %do.cond
retry.loopexit: ; preds = %lor.rhs
call void @llvm.dbg.label(metadata !20), !dbg !21
%call5 = call i32 @baz(i32* nonnull %idx), !dbg !22
%cmp6 = icmp slt i32 %call5, 0
br i1 %cmp6, label %if.then, label %do.cond
if.then: ; preds = %do.body.backedge, %retry.loopexit, %entry
%call.lcssa = phi i32 [ %call58, %entry ], [ %call, %do.body.backedge ], [ %call5, %retry.loopexit ]
ret i32 %call.lcssa
do.cond: ; preds = %retry.loopexit, %do.body.backedge, %do.cond.lr.ph.lr.ph
%0 = load i32, i32* %idx, align 4
%cmp1 = icmp slt i32 %0, 0
br i1 %cmp1, label %do.body.backedge, label %lor.rhs
lor.rhs: ; preds = %do.cond
%1 = bitcast %struct.bar* %s to i32*
%2 = load i32, i32* %1, align 4
%tobool = icmp eq i32 %2, 0
br i1 %tobool, label %do.body.backedge, label %retry.loopexit
do.body.backedge: ; preds = %lor.rhs, %do.cond
%call = call i32 @baz(i32* nonnull %idx), !dbg !22
%cmp = icmp slt i32 %call, 0
br i1 %cmp, label %if.then, label %do.cond
}
; Function Attrs: nounwind readnone speculatable
declare void @llvm.dbg.label(metadata) #0
; Function Attrs: nounwind
declare void @llvm.stackprotector(i8*, i8**) #1
attributes #0 = { nounwind readnone speculatable }
attributes #1 = { nounwind }
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, nameTableKind: GNU)
!1 = !DIFile(filename: "test.c", directory: "/home/users")
!2 = !{}
!3 = !{i32 2, !"Debug Info Version", i32 3}
!4 = distinct !DISubprogram(name: "baz", scope: !1, file: !1, line: 10, type: !5, isLocal: false, isDefinition: true, scopeLine: 11, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !2)
!5 = !DISubroutineType(types: !6)
!6 = !{!7, !8}
!7 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!8 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !7, size: 64)
!9 = !DILocation(line: 14, column: 14, scope: !10)
!10 = distinct !DILexicalBlock(scope: !4, file: !1, line: 14, column: 7)
!11 = distinct !DISubprogram(name: "test", scope: !1, file: !1, line: 22, type: !12, isLocal: false, isDefinition: true, scopeLine: 23, flags: DIFlagPrototyped, isOptimized: true, unit: !0, retainedNodes: !19)
!12 = !DISubroutineType(types: !13)
!13 = !{!7, !14}
!14 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !15, size: 64)
!15 = !DIDerivedType(tag: DW_TAG_typedef, name: "bar", file: !1, line: 3, baseType: !16)
!16 = distinct !DICompositeType(tag: DW_TAG_structure_type, name: "bar", file: !1, line: 1, size: 32, elements: !17)
!17 = !{!18}
!18 = !DIDerivedType(tag: DW_TAG_member, name: "data", scope: !16, file: !1, line: 2, baseType: !7, size: 32)
!19 = !{!20}
!20 = !DILabel(scope: !11, name: "retry", file: !1, line: 26)
!21 = !DILocation(line: 26, column: 1, scope: !11)
!22 = !DILocation(line: 28, column: 11, scope: !23)
!23 = distinct !DILexicalBlock(scope: !11, file: !1, line: 27, column: 6)
...
---
name: foo
alignment: 16
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: true
hasWinCFI: false
registers:
liveins:
- { reg: '$edi', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 0
offsetAdjustment: 0
maxAlignment: 0
adjustsStack: false
hasCalls: false
stackProtector: ''
maxCallFrameSize: 0
cvBytesOfCalleeSavedRegisters: 0
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack:
stack:
constants:
body: |
bb.0.entry:
liveins: $edi
renamable $eax = COPY $edi
RET 0, $eax
...
---
name: baz
alignment: 16
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: true
hasWinCFI: false
registers:
liveins:
- { reg: '$rdi', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 8
offsetAdjustment: 0
maxAlignment: 0
adjustsStack: true
hasCalls: true
stackProtector: ''
maxCallFrameSize: 0
cvBytesOfCalleeSavedRegisters: 8
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack:
- { id: 0, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
stack:
constants:
body: |
bb.0.entry:
successors: %bb.1(0x30000000), %bb.2(0x50000000)
liveins: $rdi, $rbx
frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
CFI_INSTRUCTION def_cfa_offset 16
CFI_INSTRUCTION offset $rbx, -16
renamable $rbx = COPY $rdi
renamable $edi = MOV32rm $rdi, 1, $noreg, 0, $noreg :: (load 4 from %ir.out)
CALL64pcrel32 @foo, csr_64, implicit $rsp, implicit $ssp, implicit $edi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-location !9
TEST32rr renamable $eax, renamable $eax, implicit-def $eflags
JCC_1 %bb.2, 9, implicit killed $eflags
; CHECK: JCC_1 %bb.2, 8, implicit $eflags
bb.1:
successors: %bb.3(0x80000000)
liveins: $eax
JMP_1 %bb.3
bb.2.if.then1:
successors: %bb.3(0x80000000)
liveins: $rbx
MOV32mi killed renamable $rbx, 1, $noreg, 0, $noreg, 1 :: (store 4 into %ir.out)
renamable $eax = MOV32r0 implicit-def dead $eflags
bb.3.cleanup:
liveins: $eax
$rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp
CFI_INSTRUCTION def_cfa_offset 8
RET 0, $eax
...
---
name: test
alignment: 16
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: true
hasWinCFI: false
registers:
liveins:
- { reg: '$rdi', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 24
offsetAdjustment: 0
maxAlignment: 4
adjustsStack: true
hasCalls: true
stackProtector: ''
maxCallFrameSize: 0
cvBytesOfCalleeSavedRegisters: 16
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack:
- { id: 0, type: spill-slot, offset: -24, size: 8, alignment: 8, stack-id: default,
callee-saved-register: '$rbx', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
- { id: 1, type: spill-slot, offset: -16, size: 8, alignment: 16, stack-id: default,
callee-saved-register: '$r14', callee-saved-restored: true, debug-info-variable: '',
debug-info-expression: '', debug-info-location: '' }
stack:
- { id: 0, name: idx, type: default, offset: -28, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
constants:
body: |
bb.0.entry:
successors: %bb.1(0x30000000), %bb.2(0x50000000)
liveins: $rdi, $r14, $rbx
frame-setup PUSH64r killed $r14, implicit-def $rsp, implicit $rsp
CFI_INSTRUCTION def_cfa_offset 16
frame-setup PUSH64r killed $rbx, implicit-def $rsp, implicit $rsp
CFI_INSTRUCTION def_cfa_offset 24
frame-setup PUSH64r undef $rax, implicit-def $rsp, implicit $rsp
CFI_INSTRUCTION def_cfa_offset 32
CFI_INSTRUCTION offset $rbx, -24
CFI_INSTRUCTION offset $r14, -16
renamable $rbx = COPY $rdi
DBG_LABEL !20, debug-location !21
renamable $rdi = LEA64r $rsp, 1, $noreg, 4, $noreg
CALL64pcrel32 @baz, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-location !22
TEST32rr renamable $eax, renamable $eax, implicit-def $eflags
JCC_1 %bb.2, 9, implicit killed $eflags
; CHECK: JCC_1 %bb.5, 8, implicit $eflags
bb.1:
successors: %bb.5(0x80000000)
liveins: $eax
JMP_1 %bb.5
bb.2:
successors: %bb.6(0x80000000)
liveins: $rbx
renamable $r14 = LEA64r $rsp, 1, $noreg, 4, $noreg
JMP_1 %bb.6
bb.3.retry.loopexit:
successors: %bb.4(0x04000000), %bb.6(0x7c000000)
liveins: $rbx, $r14
DBG_LABEL !20, debug-location !21
$rdi = COPY renamable $r14, debug-location !22
CALL64pcrel32 @baz, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-location !22
TEST32rr renamable $eax, renamable $eax, implicit-def $eflags
JCC_1 %bb.6, 9, implicit killed $eflags
bb.4:
successors: %bb.5(0x80000000)
liveins: $eax
bb.5.if.then:
liveins: $eax
$rsp = frame-destroy ADD64ri8 $rsp, 8, implicit-def dead $eflags
CFI_INSTRUCTION def_cfa_offset 24
$rbx = frame-destroy POP64r implicit-def $rsp, implicit $rsp
CFI_INSTRUCTION def_cfa_offset 16
$r14 = frame-destroy POP64r implicit-def $rsp, implicit $rsp
CFI_INSTRUCTION def_cfa_offset 8
RET 0, $eax
bb.6.do.cond:
successors: %bb.8(0x30000000), %bb.7(0x50000000)
liveins: $rbx, $r14
CMP32mi8 $rsp, 1, $noreg, 4, $noreg, 0, implicit-def $eflags :: (dereferenceable load 4 from %ir.idx)
JCC_1 %bb.8, 8, implicit killed $eflags
JMP_1 %bb.7
bb.7.lor.rhs:
successors: %bb.8(0x30000000), %bb.3(0x50000000)
liveins: $rbx, $r14
CMP32mi8 renamable $rbx, 1, $noreg, 0, $noreg, 0, implicit-def $eflags :: (load 4 from %ir.1)
JCC_1 %bb.3, 5, implicit killed $eflags
JMP_1 %bb.8
bb.8.do.body.backedge:
successors: %bb.9(0x04000000), %bb.6(0x7c000000)
liveins: $rbx, $r14
$rdi = COPY renamable $r14, debug-location !22
CALL64pcrel32 @baz, csr_64, implicit $rsp, implicit $ssp, implicit $rdi, implicit-def $rsp, implicit-def $ssp, implicit-def $eax, debug-location !22
TEST32rr renamable $eax, renamable $eax, implicit-def $eflags
JCC_1 %bb.6, 9, implicit killed $eflags
bb.9:
successors: %bb.5(0x80000000)
liveins: $eax
JMP_1 %bb.5
...
|