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Differential D73688

[ARM][LowOverheadLoops] Skip debug values
ClosedPublic

Authored by samparker on Jan 30 2020, 2:51 AM.

Details

Reviewers
SjoerdMeijer
dmgreen
Commits
rG06e12893ffb3: [ARM][LowOverheadLoops] Skip debug values
Summary

While iterating through the loop, don't inspect any dbg values.

Diff Detail

Event Timeline

samparker created this revision.Jan 30 2020, 2:51 AM
Herald added a project: Restricted Project. · View Herald TranscriptJan 30 2020, 2:51 AM
Herald added subscribers: hiraditya, kristof.beyls. · View Herald Transcript
SjoerdMeijer accepted this revision.Jan 30 2020, 3:47 AM

LGTM

This revision is now accepted and ready to land.Jan 30 2020, 3:47 AM
Closed by commit rG06e12893ffb3: [ARM][LowOverheadLoops] Skip debug values (authored by samparker). · Explain WhyJan 30 2020, 3:56 AM
This revision was automatically updated to reflect the committed changes.

Revision Contents

PathSize
llvm/
lib/
Target/
ARM/
4 lines
test/
CodeGen/
Thumb2/
LowOverheadLoops/
297 lines

Diff 241385

llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp

Show First 20 Lines • Show All 492 Lines • ▼ Show 20 Lines
else else
return false; return false;
// Find the low-overhead loop components and decide whether or not to fall // Find the low-overhead loop components and decide whether or not to fall
// back to a normal loop. Also look for a vctp instructions and decide // back to a normal loop. Also look for a vctp instructions and decide
// whether we can convert that predicate using tail predication. // whether we can convert that predicate using tail predication.
for (auto *MBB : reverse(ML->getBlocks())) { for (auto *MBB : reverse(ML->getBlocks())) {
for (auto &MI : *MBB) { for (auto &MI : *MBB) {
if (MI.getOpcode() == ARM::t2LoopDec) if (MI.isDebugValue())
continue;
else if (MI.getOpcode() == ARM::t2LoopDec)
LoLoop.Dec = &MI; LoLoop.Dec = &MI;
else if (MI.getOpcode() == ARM::t2LoopEnd) else if (MI.getOpcode() == ARM::t2LoopEnd)
LoLoop.End = &MI; LoLoop.End = &MI;
else if (isLoopStart(MI)) else if (isLoopStart(MI))
LoLoop.Start = &MI; LoLoop.Start = &MI;
else if (MI.getDesc().isCall()) { else if (MI.getDesc().isCall()) {
// TODO: Though the call will require LE to execute again, does this // TODO: Though the call will require LE to execute again, does this
// mean we should revert? Always executing LE hopefully should be // mean we should revert? Always executing LE hopefully should be
▲ Show 20 Lines • Show All 360 Lines • Show Last 20 Lines

llvm/test/CodeGen/Thumb2/LowOverheadLoops/skip-debug.mir

  • This file was added.
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py
# RUN: llc -mtriple=thumbv8.1m.main -mattr=+mve -run-pass=arm-low-overhead-loops %s -o - --verify-machineinstrs | FileCheck %s
--- |
define dso_local arm_aapcs_vfpcc void @skip_debug(i32* nocapture %a, i16* nocapture readonly %b, i32 %N) !dbg !8 {
entry:
call void @llvm.dbg.value(metadata i32* %a, metadata !17, metadata !DIExpression()), !dbg !23
call void @llvm.dbg.value(metadata i16* %b, metadata !18, metadata !DIExpression()), !dbg !23
call void @llvm.dbg.value(metadata i32 %N, metadata !19, metadata !DIExpression()), !dbg !23
%0 = load i32, i32* %a, align 4, !dbg !24
call void @llvm.dbg.value(metadata i32 %0, metadata !20, metadata !DIExpression()), !dbg !23
call void @llvm.dbg.value(metadata i32 0, metadata !21, metadata !DIExpression()), !dbg !29
%cmp7 = icmp eq i32 %N, 0, !dbg !30
%1 = add i32 %N, 3, !dbg !32
%2 = lshr i32 %1, 2, !dbg !32
%3 = shl nuw i32 %2, 2, !dbg !32
%4 = add i32 %3, -4, !dbg !32
%5 = lshr i32 %4, 2, !dbg !32
%6 = add nuw nsw i32 %5, 1, !dbg !32
br i1 %cmp7, label %for.cond.cleanup, label %vector.ph, !dbg !32
vector.ph: ; preds = %entry
%7 = insertelement <4 x i32> <i32 undef, i32 0, i32 0, i32 0>, i32 %0, i32 0, !dbg !32
call void @llvm.set.loop.iterations.i32(i32 %6), !dbg !32
%8 = shl i32 %5, 2, !dbg !32
%9 = sub i32 %N, %8, !dbg !32
br label %vector.body, !dbg !32
vector.body: ; preds = %vector.body, %vector.ph
%lsr.iv = phi i16* [ %scevgep, %vector.body ], [ %b, %vector.ph ], !dbg !33
%vec.phi = phi <4 x i32> [ %7, %vector.ph ], [ %15, %vector.body ]
%10 = phi i32 [ %6, %vector.ph ], [ %16, %vector.body ]
%11 = phi i32 [ %N, %vector.ph ], [ %13, %vector.body ]
%lsr.iv14 = bitcast i16* %lsr.iv to <4 x i16>*
%12 = call <4 x i1> @llvm.arm.mve.vctp32(i32 %11), !dbg !34
%13 = sub i32 %11, 4, !dbg !34
%wide.masked.load = call <4 x i16> @llvm.masked.load.v4i16.p0v4i16(<4 x i16>* %lsr.iv14, i32 2, <4 x i1> %12, <4 x i16> undef), !dbg !34
%14 = sext <4 x i16> %wide.masked.load to <4 x i32>, !dbg !34
%15 = sub <4 x i32> %vec.phi, %14, !dbg !38
%scevgep = getelementptr i16, i16* %lsr.iv, i32 4, !dbg !33
%16 = call i32 @llvm.loop.decrement.reg.i32.i32.i32(i32 %10, i32 1), !dbg !33
%17 = icmp ne i32 %16, 0, !dbg !33
br i1 %17, label %vector.body, label %middle.block, !dbg !33
middle.block: ; preds = %vector.body
%vec.phi.lcssa = phi <4 x i32> [ %vec.phi, %vector.body ]
%.lcssa = phi <4 x i32> [ %15, %vector.body ], !dbg !38
%18 = call <4 x i1> @llvm.arm.mve.vctp32(i32 %9), !dbg !34
%19 = select <4 x i1> %18, <4 x i32> %.lcssa, <4 x i32> %vec.phi.lcssa, !dbg !38
%20 = call i32 @llvm.experimental.vector.reduce.add.v4i32(<4 x i32> %19), !dbg !32
br label %for.cond.cleanup, !dbg !42
for.cond.cleanup: ; preds = %middle.block, %entry
%temp.0.lcssa = phi i32 [ %0, %entry ], [ %20, %middle.block ], !dbg !23
call void @llvm.dbg.value(metadata i32 %temp.0.lcssa, metadata !20, metadata !DIExpression()), !dbg !23
store i32 %temp.0.lcssa, i32* %a, align 4, !dbg !42
ret void, !dbg !43
}
declare void @llvm.dbg.value(metadata, metadata, metadata)
declare <4 x i16> @llvm.masked.load.v4i16.p0v4i16(<4 x i16>*, i32 immarg, <4 x i1>, <4 x i16>)
declare i32 @llvm.experimental.vector.reduce.add.v4i32(<4 x i32>)
declare void @llvm.set.loop.iterations.i32(i32)
declare i32 @llvm.loop.decrement.reg.i32.i32.i32(i32, i32)
declare <4 x i1> @llvm.arm.mve.vctp32(i32)
!llvm.dbg.cu = !{!0}
!llvm.module.flags = !{!3, !4, !5, !6}
!llvm.ident = !{!7}
!0 = distinct !DICompileUnit(language: DW_LANG_C99, file: !1, producer: "", isOptimized: true, runtimeVersion: 0, emissionKind: FullDebug, enums: !2, splitDebugInlining: false, nameTableKind: None)
!1 = !DIFile(filename: "skip-debug", directory: "")
!2 = !{}
!3 = !{i32 7, !"Dwarf Version", i32 4}
!4 = !{i32 2, !"Debug Info Version", i32 3}
!5 = !{i32 1, !"wchar_size", i32 4}
!6 = !{i32 1, !"min_enum_size", i32 4}
!7 = !{!""}
!8 = distinct !DISubprogram(name: "skip_debug", scope: !1, file: !1, line: 2, type: !9, scopeLine: 2, flags: DIFlagPrototyped | DIFlagAllCallsDescribed, spFlags: DISPFlagDefinition | DISPFlagOptimized, unit: !0, retainedNodes: !16)
!9 = !DISubroutineType(types: !10)
!10 = !{null, !11, !13, !15}
!11 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !12, size: 32)
!12 = !DIBasicType(name: "int", size: 32, encoding: DW_ATE_signed)
!13 = !DIDerivedType(tag: DW_TAG_pointer_type, baseType: !14, size: 32)
!14 = !DIBasicType(name: "short", size: 16, encoding: DW_ATE_signed)
!15 = !DIBasicType(name: "unsigned int", size: 32, encoding: DW_ATE_unsigned)
!16 = !{!17, !18, !19, !20, !21}
!17 = !DILocalVariable(name: "a", arg: 1, scope: !8, file: !1, line: 2, type: !11)
!18 = !DILocalVariable(name: "b", arg: 2, scope: !8, file: !1, line: 2, type: !13)
!19 = !DILocalVariable(name: "N", arg: 3, scope: !8, file: !1, line: 2, type: !15)
!20 = !DILocalVariable(name: "temp", scope: !8, file: !1, line: 3, type: !12)
!21 = !DILocalVariable(name: "i", scope: !22, file: !1, line: 4, type: !15)
!22 = distinct !DILexicalBlock(scope: !8, file: !1, line: 4, column: 3)
!23 = !DILocation(line: 0, scope: !8)
!24 = !DILocation(line: 3, column: 14, scope: !8)
!25 = !{!26, !26, i64 0}
!26 = !{!"int", !27, i64 0}
!27 = !{!"omnipotent char", !28, i64 0}
!28 = !{!"Simple C/C++ TBAA"}
!29 = !DILocation(line: 0, scope: !22)
!30 = !DILocation(line: 4, column: 26, scope: !31)
!31 = distinct !DILexicalBlock(scope: !22, file: !1, line: 4, column: 3)
!32 = !DILocation(line: 4, column: 3, scope: !22)
!33 = !DILocation(line: 4, column: 31, scope: !31)
!34 = !DILocation(line: 5, column: 13, scope: !35)
!35 = distinct !DILexicalBlock(scope: !31, file: !1, line: 4, column: 36)
!36 = !{!37, !37, i64 0}
!37 = !{!"short", !27, i64 0}
!38 = !DILocation(line: 5, column: 10, scope: !35)
!39 = distinct !{!39, !32, !40, !41}
!40 = !DILocation(line: 6, column: 3, scope: !22)
!41 = !{!"llvm.loop.isvectorized", i32 1}
!42 = !DILocation(line: 7, column: 6, scope: !8)
!43 = !DILocation(line: 8, column: 1, scope: !8)
...
---
name: skip_debug
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: '$r2', virtual-reg: '' }
frameInfo:
isFrameAddressTaken: false
isReturnAddressTaken: false
hasStackMap: false
hasPatchPoint: false
stackSize: 16
offsetAdjustment: -8
maxAlignment: 4
adjustsStack: false
hasCalls: false
stackProtector: ''
maxCallFrameSize: 0
cvBytesOfCalleeSavedRegisters: 0
hasOpaqueSPAdjustment: false
hasVAStart: false
hasMustTailInVarArgFunc: false
localFrameSize: 0
savePoint: ''
restorePoint: ''
fixedStack: []
stack:
- { id: 0, name: '', type: spill-slot, offset: -4, size: 4, alignment: 4,
stack-id: default, callee-saved-register: '$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: '' }
callSites: []
constants: []
machineFunctionInfo: {}
body: |
; CHECK-LABEL: name: skip_debug
; CHECK: bb.0.entry:
; CHECK: successors: %bb.4(0x30000000), %bb.1(0x50000000)
; CHECK: liveins: $lr, $r0, $r1, $r2, $r4, $r6
; CHECK: DBG_VALUE $r0, $noreg, !17, !DIExpression(), debug-location !23
; CHECK: DBG_VALUE $r0, $noreg, !17, !DIExpression(), debug-location !23
; CHECK: DBG_VALUE $r1, $noreg, !18, !DIExpression(), debug-location !23
; CHECK: DBG_VALUE $r1, $noreg, !18, !DIExpression(), debug-location !23
; CHECK: DBG_VALUE $r2, $noreg, !19, !DIExpression(), debug-location !23
; CHECK: DBG_VALUE $r2, $noreg, !19, !DIExpression(), debug-location !23
; CHECK: frame-setup tPUSH 14, $noreg, killed $r4, killed $r6, killed $lr, implicit-def $sp, implicit $sp
; CHECK: frame-setup CFI_INSTRUCTION def_cfa_offset 16
; CHECK: frame-setup CFI_INSTRUCTION offset $lr, -4
; CHECK: frame-setup CFI_INSTRUCTION offset $r7, -8
; CHECK: frame-setup CFI_INSTRUCTION offset $r6, -12
; CHECK: frame-setup CFI_INSTRUCTION offset $r4, -16
; CHECK: dead $r7 = frame-setup tADDrSPi $sp, 2, 14, $noreg
; CHECK: frame-setup CFI_INSTRUCTION def_cfa $r7, 8
; CHECK: renamable $r12 = t2LDRi12 renamable $r0, 0, 14, $noreg, debug-location !24 :: (load 4 from %ir.a)
; CHECK: DBG_VALUE 0, $noreg, !21, !DIExpression(), debug-location !25
; CHECK: DBG_VALUE $r12, $noreg, !20, !DIExpression(), debug-location !23
; CHECK: tCBZ $r2, %bb.4, debug-location !28
; CHECK: bb.1.vector.ph:
; CHECK: successors: %bb.2(0x80000000)
; CHECK: liveins: $r0, $r1, $r2, $r12
; CHECK: renamable $r3, dead $cpsr = tADDi3 renamable $r2, 3, 14, $noreg, debug-location !28
; CHECK: renamable $lr = t2MOVi 1, 14, $noreg, $noreg
; CHECK: renamable $r3 = t2BICri killed renamable $r3, 3, 14, $noreg, $noreg, debug-location !28
; CHECK: renamable $r4, dead $cpsr = tMOVi8 0, 14, $noreg
; CHECK: renamable $r3, dead $cpsr = tSUBi8 killed renamable $r3, 4, 14, $noreg, debug-location !28
; CHECK: renamable $q0 = MVE_VDUP32 killed renamable $r4, 0, $noreg, undef renamable $q0, debug-location !28
; CHECK: renamable $q0 = MVE_VMOV_to_lane_32 killed renamable $q0, killed renamable $r12, 0, 14, $noreg, debug-location !28
; CHECK: renamable $lr = nuw nsw t2ADDrs killed renamable $lr, renamable $r3, 19, 14, $noreg, $noreg, debug-location !28
; CHECK: renamable $r3, dead $cpsr = tLSRri killed renamable $r3, 2, 14, $noreg, debug-location !28
; CHECK: renamable $r3 = t2SUBrs renamable $r2, killed renamable $r3, 18, 14, $noreg, $noreg, debug-location !28
; CHECK: $lr = t2DLS killed renamable $lr, debug-location !28
; CHECK: bb.2.vector.body:
; CHECK: successors: %bb.2(0x7c000000), %bb.3(0x04000000)
; CHECK: liveins: $lr, $q0, $r0, $r1, $r2, $r3
; CHECK: renamable $vpr = MVE_VCTP32 renamable $r2, 0, $noreg, debug-location !30
; CHECK: DBG_VALUE $vpr, $noreg, !17, !DIExpression(), debug-location !30
; CHECK: $q1 = MVE_VORR killed $q0, killed $q0, 0, $noreg, undef $q1
; CHECK: MVE_VPST 8, implicit $vpr, debug-location !30
; CHECK: renamable $r1, renamable $q0 = MVE_VLDRHU32_post killed renamable $r1, 8, 1, killed renamable $vpr, debug-location !30 :: (load 8 from %ir.lsr.iv14, align 2)
; CHECK: renamable $r2, dead $cpsr = tSUBi8 killed renamable $r2, 4, 14, $noreg, debug-location !30
; CHECK: renamable $q0 = MVE_VMOVLs16bh killed renamable $q0, 0, $noreg, undef renamable $q0, debug-location !30
; CHECK: renamable $q0 = MVE_VSUBi32 renamable $q1, killed renamable $q0, 0, $noreg, undef renamable $q0, debug-location !32
; CHECK: $lr = t2LEUpdate killed renamable $lr, %bb.2, debug-location !29
; CHECK: bb.3.middle.block:
; CHECK: successors: %bb.4(0x80000000)
; CHECK: liveins: $q0, $q1, $r0, $r3
; CHECK: renamable $vpr = MVE_VCTP32 killed renamable $r3, 0, $noreg, debug-location !30
; CHECK: renamable $q0 = MVE_VPSEL killed renamable $q0, killed renamable $q1, 0, killed renamable $vpr, debug-location !32
; CHECK: renamable $r12 = MVE_VADDVu32no_acc killed renamable $q0, 0, $noreg, debug-location !28
; CHECK: bb.4.for.cond.cleanup:
; CHECK: liveins: $r0, $r12
; CHECK: DBG_VALUE $r12, $noreg, !20, !DIExpression(), debug-location !23
; CHECK: t2STRi12 killed renamable $r12, killed renamable $r0, 0, 14, $noreg, debug-location !33 :: (store 4 into %ir.a)
; CHECK: tPOP_RET 14, $noreg, def $r4, def $r6, def $r7, def $pc, debug-location !34
bb.0.entry:
successors: %bb.4(0x30000000), %bb.1(0x50000000)
liveins: $r0, $r1, $r2, $r4, $r6, $lr
DBG_VALUE $r0, $noreg, !17, !DIExpression(), debug-location !23
DBG_VALUE $r0, $noreg, !17, !DIExpression(), debug-location !23
DBG_VALUE $r1, $noreg, !18, !DIExpression(), debug-location !23
DBG_VALUE $r1, $noreg, !18, !DIExpression(), debug-location !23
DBG_VALUE $r2, $noreg, !19, !DIExpression(), debug-location !23
DBG_VALUE $r2, $noreg, !19, !DIExpression(), debug-location !23
frame-setup tPUSH 14, $noreg, killed $r4, killed $r6, killed $lr, implicit-def $sp, implicit $sp
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 tADDrSPi $sp, 2, 14, $noreg
frame-setup CFI_INSTRUCTION def_cfa $r7, 8
renamable $r12 = t2LDRi12 renamable $r0, 0, 14, $noreg, debug-location !24 :: (load 4 from %ir.a)
DBG_VALUE 0, $noreg, !21, !DIExpression(), debug-location !29
DBG_VALUE $r12, $noreg, !20, !DIExpression(), debug-location !23
tCBZ $r2, %bb.4, debug-location !32
bb.1.vector.ph:
successors: %bb.2(0x80000000)
liveins: $r0, $r1, $r2, $r12
renamable $r3, dead $cpsr = tADDi3 renamable $r2, 3, 14, $noreg, debug-location !32
renamable $lr = t2MOVi 1, 14, $noreg, $noreg
renamable $r3 = t2BICri killed renamable $r3, 3, 14, $noreg, $noreg, debug-location !32
renamable $r4, dead $cpsr = tMOVi8 0, 14, $noreg
renamable $r3, dead $cpsr = tSUBi8 killed renamable $r3, 4, 14, $noreg, debug-location !32
renamable $q0 = MVE_VDUP32 killed renamable $r4, 0, $noreg, undef renamable $q0, debug-location !32
renamable $q0 = MVE_VMOV_to_lane_32 killed renamable $q0, killed renamable $r12, 0, 14, $noreg, debug-location !32
renamable $lr = nuw nsw t2ADDrs killed renamable $lr, renamable $r3, 19, 14, $noreg, $noreg, debug-location !32
renamable $r3, dead $cpsr = tLSRri killed renamable $r3, 2, 14, $noreg, debug-location !32
renamable $r3 = t2SUBrs renamable $r2, killed renamable $r3, 18, 14, $noreg, $noreg, debug-location !32
t2DoLoopStart renamable $lr, debug-location !32
bb.2.vector.body:
successors: %bb.2(0x7c000000), %bb.3(0x04000000)
liveins: $lr, $q0, $r0, $r1, $r2, $r3
renamable $vpr = MVE_VCTP32 renamable $r2, 0, $noreg, debug-location !34
DBG_VALUE $vpr, $noreg, !17, !DIExpression(), debug-location !34
$q1 = MVE_VORR killed $q0, $q0, 0, $noreg, undef $q1
MVE_VPST 8, implicit $vpr, debug-location !34
renamable $r1, renamable $q0 = MVE_VLDRHU32_post killed renamable $r1, 8, 1, killed renamable $vpr, debug-location !34 :: (load 8 from %ir.lsr.iv14, align 2)
renamable $r2, dead $cpsr = tSUBi8 killed renamable $r2, 4, 14, $noreg, debug-location !34
renamable $q0 = MVE_VMOVLs16bh killed renamable $q0, 0, $noreg, undef renamable $q0, debug-location !34
renamable $lr = t2LoopDec killed renamable $lr, 1, debug-location !33
renamable $q0 = MVE_VSUBi32 renamable $q1, killed renamable $q0, 0, $noreg, undef renamable $q0, debug-location !38
t2LoopEnd renamable $lr, %bb.2, implicit-def dead $cpsr, debug-location !33
tB %bb.3, 14, $noreg, debug-location !33
bb.3.middle.block:
successors: %bb.4(0x80000000)
liveins: $q0, $q1, $r0, $r3
renamable $vpr = MVE_VCTP32 killed renamable $r3, 0, $noreg, debug-location !34
renamable $q0 = MVE_VPSEL killed renamable $q0, killed renamable $q1, 0, killed renamable $vpr, debug-location !38
renamable $r12 = MVE_VADDVu32no_acc killed renamable $q0, 0, $noreg, debug-location !32
bb.4.for.cond.cleanup:
liveins: $r0, $r12
DBG_VALUE $r12, $noreg, !20, !DIExpression(), debug-location !23
t2STRi12 killed renamable $r12, killed renamable $r0, 0, 14, $noreg, debug-location !42 :: (store 4 into %ir.a)
tPOP_RET 14, $noreg, def $r4, def $r6, def $r7, def $pc, debug-location !43
...