# RUN: llc -O0 -run-pass=arm-low-overhead-loops -o - -verify-machineinstrs %s | FileCheck %s
# CHECK-NOT: WLS
# CHECK-NOT: WhileLoopStart
--- |
target datalayout = "e-m:e-p:32:32-Fi8-i64:64-v128:64:128-a:0:32-n32-S64"
target triple = "thumbv8.1m.main"
define void @size_limit(i32* nocapture %a, i32* nocapture readonly %b, i32* nocapture readonly %c, i32 %N) #0 {
entry:
br label %while
for.cond.cleanup: ; preds = %while, %for.body
ret void
for.body.preheader: ; preds = %while
%scevgep = getelementptr i32, i32* %a, i32 -1
%scevgep4 = getelementptr i32, i32* %c, i32 -1
%scevgep8 = getelementptr i32, i32* %b, i32 -1
br label %for.body
for.body: ; preds = %for.body, %for.body.preheader
%lsr.iv9 = phi i32* [ %scevgep8, %for.body.preheader ], [ %scevgep10, %for.body ]
%lsr.iv5 = phi i32* [ %scevgep4, %for.body.preheader ], [ %scevgep6, %for.body ]
%lsr.iv1 = phi i32* [ %scevgep, %for.body.preheader ], [ %scevgep2, %for.body ]
%0 = phi i32 [ %N, %for.body.preheader ], [ %3, %for.body ]
%scevgep11 = getelementptr i32, i32* %lsr.iv9, i32 1
%1 = load i32, i32* %scevgep11, align 4
%scevgep7 = getelementptr i32, i32* %lsr.iv5, i32 1
%2 = load i32, i32* %scevgep7, align 4
%mul = mul nsw i32 %2, %1
%scevgep3 = getelementptr i32, i32* %lsr.iv1, i32 1
store i32 %mul, i32* %scevgep3, align 4
%scevgep2 = getelementptr i32, i32* %lsr.iv1, i32 1
%scevgep6 = getelementptr i32, i32* %lsr.iv5, i32 1
%scevgep10 = getelementptr i32, i32* %lsr.iv9, 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
while: ; preds = %entry
%cmp8 = call i1 @llvm.test.set.loop.iterations.i32(i32 %N)
br i1 %cmp8, label %for.body.preheader, label %for.cond.cleanup
}
; Function Attrs: nounwind
declare i32 @llvm.arm.space(i32 immarg, i32) #1
; Function Attrs: noduplicate nounwind
declare i1 @llvm.test.set.loop.iterations.i32(i32) #2
; Function Attrs: noduplicate nounwind
declare i32 @llvm.loop.decrement.reg.i32.i32.i32(i32, i32) #2
attributes #0 = { "target-features"="+lob" }
attributes #1 = { nounwind }
attributes #2 = { noduplicate nounwind }
...
---
name: size_limit
alignment: 2
exposesReturnsTwice: false
legalized: false
regBankSelected: false
selected: false
failedISel: false
tracksRegLiveness: true
hasWinCFI: false
registers: []
liveins:
- { reg: '$r0', virtual-reg: '' }
- { reg: '$r1', virtual-reg: '' }
- { reg: '$r2', virtual-reg: '' }
- { reg: '$r3', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 40
offsetAdjustment: 0
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: -12, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 1, name: '', type: spill-slot, offset: -16, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 2, name: '', type: spill-slot, offset: -20, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 3, name: '', type: spill-slot, offset: -24, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 4, name: '', type: spill-slot, 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: '' }
- { id: 5, name: '', type: spill-slot, offset: -32, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 6, name: '', type: spill-slot, offset: -36, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 7, name: '', type: spill-slot, offset: -40, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 8, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$lr', callee-saved-restored: false,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
- { id: 9, name: '', type: spill-slot, offset: -8, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$r4', callee-saved-restored: true,
debug-info-variable: '', debug-info-expression: '', debug-info-location: '' }
callSites: []
constants: []
machineFunctionInfo: {}
body: |
bb.0.entry:
successors: %bb.4(0x80000000)
liveins: $r0, $r1, $r2, $r3, $r4, $lr
frame-setup tPUSH 14, $noreg, killed $r4, killed $lr, implicit-def $sp, implicit $sp
frame-setup CFI_INSTRUCTION def_cfa_offset 8
frame-setup CFI_INSTRUCTION offset $lr, -4
frame-setup CFI_INSTRUCTION offset $r4, -8
$sp = frame-setup tSUBspi $sp, 8, 14, $noreg
frame-setup CFI_INSTRUCTION def_cfa_offset 40
tSTRspi killed $r3, $sp, 7, 14, $noreg :: (store (s32) into %stack.0)
tSTRspi killed $r2, $sp, 6, 14, $noreg :: (store (s32) into %stack.1)
tSTRspi killed $r1, $sp, 5, 14, $noreg :: (store (s32) into %stack.2)
tSTRspi killed $r0, $sp, 4, 14, $noreg :: (store (s32) into %stack.3)
tB %bb.4, 14, $noreg
bb.1.for.cond.cleanup:
$sp = tADDspi $sp, 8, 14, $noreg
tPOP_RET 14, $noreg, def $r4, def $pc
bb.2.for.body.preheader:
successors: %bb.3(0x80000000)
$r0 = tLDRspi $sp, 4, 14, $noreg :: (load (s32) from %stack.3)
renamable $r1, dead $cpsr = tSUBi3 killed renamable $r0, 4, 14, $noreg
$r2 = tLDRspi $sp, 6, 14, $noreg :: (load (s32) from %stack.1)
renamable $r3, dead $cpsr = tSUBi3 killed renamable $r2, 4, 14, $noreg
$r12 = t2LDRi12 $sp, 20, 14, $noreg :: (load (s32) from %stack.2)
renamable $lr = t2SUBri killed renamable $r12, 4, 14, $noreg, $noreg
$r4 = tLDRspi $sp, 7, 14, $noreg :: (load (s32) from %stack.0)
t2STRi12 killed $lr, $sp, 12, 14, $noreg :: (store (s32) into %stack.4)
tSTRspi killed $r3, $sp, 2, 14, $noreg :: (store (s32) into %stack.5)
tSTRspi killed $r1, $sp, 1, 14, $noreg :: (store (s32) into %stack.6)
tSTRspi killed $r4, $sp, 0, 14, $noreg :: (store (s32) into %stack.7)
tB %bb.3, 14, $noreg
bb.3.for.body:
successors: %bb.3(0x40000000), %bb.1(0x40000000)
$r0 = tLDRspi $sp, 0, 14, $noreg :: (load (s32) from %stack.7)
$r1 = tLDRspi $sp, 1, 14, $noreg :: (load (s32) from %stack.6)
$r2 = tLDRspi $sp, 2, 14, $noreg :: (load (s32) from %stack.5)
$r3 = tLDRspi $sp, 3, 14, $noreg :: (load (s32) from %stack.4)
renamable $r12, renamable $r3 = t2LDR_PRE renamable $r3, 4, 14, $noreg :: (load (s32) from %ir.scevgep11)
renamable $lr, renamable $r2 = t2LDR_PRE renamable $r2, 4, 14, $noreg :: (load (s32) from %ir.scevgep7)
renamable $r12 = nsw t2MUL killed renamable $lr, killed renamable $r12, 14, $noreg
early-clobber renamable $r1 = t2STR_PRE killed renamable $r12, renamable $r1, 4, 14, $noreg :: (store (s32) into %ir.scevgep3)
$lr = tMOVr killed $r0, 14, $noreg
renamable $lr = t2LoopDec killed renamable $lr, 1
$r0 = tMOVr $lr, 14, $noreg
tSTRspi killed $r0, $sp, 0, 14, $noreg :: (store (s32) into %stack.7)
tSTRspi killed $r1, $sp, 1, 14, $noreg :: (store (s32) into %stack.6)
tSTRspi killed $r2, $sp, 2, 14, $noreg :: (store (s32) into %stack.5)
tSTRspi killed $r3, $sp, 3, 14, $noreg :: (store (s32) into %stack.4)
t2LoopEnd killed renamable $lr, %bb.3, implicit-def dead $cpsr
tB %bb.1, 14, $noreg
bb.4.while:
successors: %bb.2(0x40000000), %bb.1(0x40000000)
$r0 = tLDRspi $sp, 7, 14, $noreg :: (load (s32) from %stack.0)
$lr = t2WhileLoopStartLR killed renamable $r0, %bb.1, implicit-def dead $cpsr
tB %bb.2, 14, $noreg
...