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|
# RUN: llc -mtriple=thumbv8.1m.main %s -run-pass=arm-low-overhead-loops -o -
# CHECK: bb.1.for.body.preheader:
# CHECK: $lr = t2DLS
# CHECK-NOT: t2LoopDec
# CHECK: bb.6.for.inc:
# CHECK: $lr = t2LEUpdate renamable $lr, %bb.2
--- |
target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
target triple = "thumbv8.1m.main-unknown-unknown"
; Function Attrs: norecurse nounwind readonly
define dso_local arm_aapcscc i32 @search(i8* nocapture readonly %c, i32 %N) local_unnamed_addr #0 {
entry:
%cmp11 = icmp eq i32 %N, 0
br i1 %cmp11, label %for.cond.cleanup, label %for.body.preheader
for.body.preheader:
call void @llvm.set.loop.iterations.i32(i32 %N)
br label %for.body
for.cond.cleanup:
%found.0.lcssa = phi i32 [ 0, %entry ], [ %found.1, %for.inc ]
%spaces.0.lcssa = phi i32 [ 0, %entry ], [ %spaces.1, %for.inc ]
%sub = sub nsw i32 %found.0.lcssa, %spaces.0.lcssa
ret i32 %sub
for.body:
%lsr.iv1 = phi i8* [ %c, %for.body.preheader ], [ %scevgep, %for.inc ]
%spaces.013 = phi i32 [ %spaces.1, %for.inc ], [ 0, %for.body.preheader ]
%found.012 = phi i32 [ %found.1, %for.inc ], [ 0, %for.body.preheader ]
%0 = phi i32 [ %N, %for.body.preheader ], [ %3, %for.inc ]
%1 = load i8, i8* %lsr.iv1, align 1
%2 = zext i8 %1 to i32
switch i32 %2, label %for.inc [
i32 108, label %sw.bb
i32 111, label %sw.bb
i32 112, label %sw.bb
i32 32, label %sw.bb1
]
sw.bb:
%inc = add nsw i32 %found.012, 1
br label %for.inc
sw.bb1:
%inc2 = add nsw i32 %spaces.013, 1
br label %for.inc
for.inc:
%found.1 = phi i32 [ %found.012, %for.body ], [ %found.012, %sw.bb1 ], [ %inc, %sw.bb ]
%spaces.1 = phi i32 [ %spaces.013, %for.body ], [ %inc2, %sw.bb1 ], [ %spaces.013, %sw.bb ]
%scevgep = getelementptr i8, i8* %lsr.iv1, i32 1
%3 = call i32 @llvm.loop.decrement.reg.i32.i32.i32(i32 %0, i32 1)
%4 = icmp ne i32 %3, 0
br i1 %4, label %for.body, label %for.cond.cleanup
}
declare void @llvm.set.loop.iterations.i32(i32) #1
declare i32 @llvm.loop.decrement.reg.i32.i32.i32(i32, i32) #1
declare void @llvm.stackprotector(i8*, i8**) #2
attributes #0 = { norecurse nounwind readonly "correctly-rounded-divide-sqrt-fp-math"="false" "disable-tail-calls"="false" "less-precise-fpmad"="false" "min-legal-vector-width"="0" "no-frame-pointer-elim"="true" "no-frame-pointer-elim-non-leaf" "no-infs-fp-math"="false" "no-jump-tables"="false" "no-nans-fp-math"="false" "no-signed-zeros-fp-math"="false" "no-trapping-math"="false" "stack-protector-buffer-size"="8" "target-cpu"="generic" "target-features"="+armv8.1-m.main,+hwdiv,+ras,+soft-float,+strict-align,+thumb-mode,-crypto,-d32,-dotprod,-fp-armv8,-fp-armv8d16,-fp-armv8d16sp,-fp-armv8sp,-fp16,-fp16fml,-fp64,-fpregs,-fullfp16,-neon,-vfp2,-vfp2d16,-vfp2d16sp,-vfp2sp,-vfp3,-vfp3d16,-vfp3d16sp,-vfp3sp,-vfp4,-vfp4d16,-vfp4d16sp,-vfp4sp" "unsafe-fp-math"="false" "use-soft-float"="true" }
attributes #1 = { noduplicate nounwind }
attributes #2 = { nounwind }
...
---
name: search
alignment: 1
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: true
hasWinCFI: false
registers: []
liveins:
- { reg: '$r0', virtual-reg: '' }
- { reg: '$r1', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 16
offsetAdjustment: -8
maxAlignment: 4
adjustsStack: false
hasCalls: false
stackProtector: ''
maxCallFrameSize: 0
cvBytesOfCalleeSavedRegisters: 0
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack: []
stack:
- { id: 0, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$lr', callee-saved-restored: false,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 1, name: '', type: spill-slot, offset: -8, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r7', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 2, name: '', type: spill-slot, offset: -12, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r6', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 3, name: '', type: spill-slot, offset: -16, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r4', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
constants: []
machineFunctionInfo: {}
body: |
bb.0.entry:
successors: %bb.1(0x30000000), %bb.3(0x50000000)
liveins: $r0, $r1, $r4, $r6, $lr
$sp = frame-setup t2STMDB_UPD $sp, 14, $noreg, killed $r4, killed $r6, $r7, killed $lr
frame-setup CFI_INSTRUCTION def_cfa_offset 16
frame-setup CFI_INSTRUCTION offset $lr, -4
frame-setup CFI_INSTRUCTION offset $r7, -8
frame-setup CFI_INSTRUCTION offset $r6, -12
frame-setup CFI_INSTRUCTION offset $r4, -16
$r7 = frame-setup t2ADDri $sp, 8, 14, $noreg, $noreg
frame-setup CFI_INSTRUCTION def_cfa $r7, 8
t2CMPri $r1, 0, 14, $noreg, implicit-def $cpsr
t2Bcc %bb.1, 0, killed $cpsr
bb.3.for.body.preheader:
successors: %bb.4(0x80000000)
liveins: $r0, $r1
$lr = tMOVr $r1, 14, $noreg
t2DoLoopStart killed $r1
renamable $r1 = t2MOVi 0, 14, $noreg, $noreg
renamable $r12 = t2MOVi 1, 14, $noreg, $noreg
renamable $r2 = t2MOVi 0, 14, $noreg, $noreg
bb.4.for.body:
successors: %bb.5(0x26666665), %bb.6(0x5999999b)
liveins: $lr, $r0, $r1, $r2, $r12
renamable $r3 = t2LDRBi12 renamable $r0, 0, 14, $noreg :: (load 1 from %ir.lsr.iv1)
renamable $r4 = t2SUBri renamable $r3, 108, 14, $noreg, $noreg
renamable $lr = t2LoopDec killed renamable $lr, 1
t2CMPri renamable $r4, 4, 14, $noreg, implicit-def $cpsr
t2Bcc %bb.5, 8, killed $cpsr
bb.6.for.body:
successors: %bb.7(0x6db6db6e), %bb.5(0x12492492)
liveins: $lr, $r0, $r1, $r2, $r3, $r4, $r12
renamable $r4 = t2LSLrr renamable $r12, killed renamable $r4, 14, $noreg, $noreg
t2TSTri killed renamable $r4, 25, 14, $noreg, implicit-def $cpsr
t2Bcc %bb.5, 0, killed $cpsr
bb.7.sw.bb:
successors: %bb.8(0x80000000)
liveins: $lr, $r0, $r1, $r2, $r12
renamable $r2 = nsw t2ADDri killed renamable $r2, 1, 14, $noreg, $noreg
t2B %bb.8, 14, $noreg
bb.5.for.body:
successors: %bb.8(0x80000000)
liveins: $lr, $r0, $r1, $r2, $r3, $r12
t2CMPri killed renamable $r3, 32, 14, $noreg, implicit-def $cpsr
BUNDLE implicit-def dead $itstate, implicit-def $r1, implicit killed $r1, implicit killed $cpsr {
t2IT 0, 8, implicit-def $itstate
renamable $r1 = nsw t2ADDri killed renamable $r1, 1, 0, killed $cpsr, $noreg, implicit $r1, implicit internal killed $itstate
}
bb.8.for.inc:
successors: %bb.4(0x7c000000), %bb.2(0x04000000)
liveins: $lr, $r0, $r1, $r2, $r12
renamable $r0 = t2ADDri killed renamable $r0, 1, 14, $noreg, $noreg
t2LoopEnd renamable $lr, %bb.4
t2B %bb.2, 14, $noreg
bb.2.for.cond.cleanup:
liveins: $r1, $r2
renamable $r0 = nsw t2SUBrr killed renamable $r2, killed renamable $r1, 14, $noreg, $noreg
$sp = t2LDMIA_RET $sp, 14, $noreg, def $r4, def $r6, def $r7, def $pc, implicit killed $r0
bb.1:
renamable $r2 = t2MOVi 0, 14, $noreg, $noreg
renamable $r1 = t2MOVi 0, 14, $noreg, $noreg
renamable $r0 = nsw t2SUBrr killed renamable $r2, killed renamable $r1, 14, $noreg, $noreg
$sp = t2LDMIA_RET $sp, 14, $noreg, def $r4, def $r6, def $r7, def $pc, implicit killed $r0
...
|
