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oskarwirgaoskarwirga
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Refactor recomputeLiveIns to operate on whole CFG
1 parent 7b46225 commit cca78cc

30 files changed

+1996
-1698
lines changed

‎llvm/include/llvm/CodeGen/LivePhysRegs.h

Lines changed: 23 additions & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -31,6 +31,7 @@
3131

3232
#include "llvm/ADT/SparseSet.h"
3333
#include "llvm/CodeGen/MachineBasicBlock.h"
34+
#include "llvm/CodeGen/MachineFunction.h"
3435
#include "llvm/CodeGen/TargetRegisterInfo.h"
3536
#include "llvm/MC/MCRegister.h"
3637
#include "llvm/MC/MCRegisterInfo.h"
@@ -193,11 +194,31 @@ void addLiveIns(MachineBasicBlock &MBB, const LivePhysRegs &LiveRegs);
193194
void computeAndAddLiveIns(LivePhysRegs &LiveRegs,
194195
MachineBasicBlock &MBB);
195196

196-
/// Convenience function for recomputing live-in's for \p MBB.
197-
static inline void recomputeLiveIns(MachineBasicBlock &MBB) {
197+
/// Function to update the live-in's for a basic block and return whether any
198+
/// changes were made.
199+
static inline bool updateBlockLiveInfo(MachineBasicBlock &MBB) {
198200
LivePhysRegs LPR;
201+
auto oldLiveIns = MBB.getLiveIns();
202+
199203
MBB.clearLiveIns();
200204
computeAndAddLiveIns(LPR, MBB);
205+
MBB.sortUniqueLiveIns();
206+
207+
auto newLiveIns = MBB.getLiveIns();
208+
return oldLiveIns != newLiveIns;
209+
}
210+
211+
/// Convenience function for recomputing live-in's for the entire CFG until
212+
/// convergence is reached.
213+
static inline void recomputeLiveIns(MachineFunction &MF) {
214+
bool anyChanged;
215+
do {
216+
anyChanged = false;
217+
for (auto MFI = MF.rbegin(), MFE = MF.rend(); MFI != MFE; ++MFI) {
218+
MachineBasicBlock &MBB = *MFI;
219+
anyChanged |= updateBlockLiveInfo(MBB);
220+
}
221+
} while (anyChanged);
201222
}
202223

203224
} // end namespace llvm

‎llvm/include/llvm/CodeGen/MachineBasicBlock.h

Lines changed: 6 additions & 0 deletions
Original file line numberDiff line numberDiff line change
@@ -111,6 +111,10 @@ class MachineBasicBlock
111111

112112
RegisterMaskPair(MCPhysReg PhysReg, LaneBitmask LaneMask)
113113
: PhysReg(PhysReg), LaneMask(LaneMask) {}
114+
115+
bool operator==(const RegisterMaskPair &other) const {
116+
return PhysReg == other.PhysReg && LaneMask == other.LaneMask;
117+
}
114118
};
115119

116120
private:
@@ -473,6 +477,8 @@ class MachineBasicBlock
473477
/// Remove entry from the livein set and return iterator to the next.
474478
livein_iterator removeLiveIn(livein_iterator I);
475479

480+
std::vector<RegisterMaskPair> getLiveIns() const { return LiveIns; }
481+
476482
class liveout_iterator {
477483
public:
478484
using iterator_category = std::input_iterator_tag;

‎llvm/lib/CodeGen/BranchFolding.cpp

Lines changed: 1 addition & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -2048,8 +2048,7 @@ bool BranchFolder::HoistCommonCodeInSuccs(MachineBasicBlock *MBB) {
20482048
FBB->erase(FBB->begin(), FIB);
20492049

20502050
if (UpdateLiveIns) {
2051-
recomputeLiveIns(*TBB);
2052-
recomputeLiveIns(*FBB);
2051+
recomputeLiveIns(*MBB->getParent());
20532052
}
20542053

20552054
++NumHoist;

‎llvm/lib/Target/AArch64/AArch64FrameLowering.cpp

Lines changed: 1 addition & 2 deletions
Original file line numberDiff line numberDiff line change
@@ -4339,8 +4339,7 @@ AArch64FrameLowering::inlineStackProbeLoopExactMultiple(
43394339
ExitMBB->transferSuccessorsAndUpdatePHIs(&MBB);
43404340
MBB.addSuccessor(LoopMBB);
43414341
// Update liveins.
4342-
recomputeLiveIns(*LoopMBB);
4343-
recomputeLiveIns(*ExitMBB);
4342+
recomputeLiveIns(MF);
43444343

43454344
return ExitMBB->begin();
43464345
}

‎llvm/lib/Target/AArch64/AArch64InstrInfo.cpp

Lines changed: 1 addition & 3 deletions
Original file line numberDiff line numberDiff line change
@@ -9597,9 +9597,7 @@ AArch64InstrInfo::probedStackAlloc(MachineBasicBlock::iterator MBBI,
95979597

95989598
// Update liveins.
95999599
if (MF.getRegInfo().reservedRegsFrozen()) {
9600-
recomputeLiveIns(*LoopTestMBB);
9601-
recomputeLiveIns(*LoopBodyMBB);
9602-
recomputeLiveIns(*ExitMBB);
9600+
recomputeLiveIns(MF);
96039601
}
96049602

96059603
return ExitMBB->begin();

‎llvm/lib/Target/ARM/ARMLowOverheadLoops.cpp

Lines changed: 1 addition & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -1806,12 +1806,7 @@ void ARMLowOverheadLoops::Expand(LowOverheadLoop &LoLoop) {
18061806
PostOrderLoopTraversal DFS(LoLoop.ML, *MLI);
18071807
DFS.ProcessLoop();
18081808
const SmallVectorImpl<MachineBasicBlock*> &PostOrder = DFS.getOrder();
1809-
for (auto *MBB : PostOrder) {
1810-
recomputeLiveIns(*MBB);
1811-
// FIXME: For some reason, the live-in print order is non-deterministic for
1812-
// our tests and I can't out why... So just sort them.
1813-
MBB->sortUniqueLiveIns();
1814-
}
1809+
recomputeLiveIns(*LoLoop.MF);
18151810

18161811
for (auto *MBB : reverse(PostOrder))
18171812
recomputeLivenessFlags(*MBB);

‎llvm/lib/Target/PowerPC/PPCExpandAtomicPseudoInsts.cpp

Lines changed: 2 additions & 5 deletions
Original file line numberDiff line numberDiff line change
@@ -208,8 +208,7 @@ bool PPCExpandAtomicPseudo::expandAtomicRMW128(
208208
.addMBB(LoopMBB);
209209
CurrentMBB->addSuccessor(LoopMBB);
210210
CurrentMBB->addSuccessor(ExitMBB);
211-
recomputeLiveIns(*LoopMBB);
212-
recomputeLiveIns(*ExitMBB);
211+
recomputeLiveIns(*MF);
213212
NMBBI = MBB.end();
214213
MI.eraseFromParent();
215214
return true;
@@ -286,9 +285,7 @@ bool PPCExpandAtomicPseudo::expandAtomicCmpSwap128(
286285
CurrentMBB->addSuccessor(LoopCmpMBB);
287286
CurrentMBB->addSuccessor(ExitMBB);
288287

289-
recomputeLiveIns(*LoopCmpMBB);
290-
recomputeLiveIns(*CmpSuccMBB);
291-
recomputeLiveIns(*ExitMBB);
288+
recomputeLiveIns(*MF);
292289
NMBBI = MBB.end();
293290
MI.eraseFromParent();
294291
return true;

‎llvm/lib/Target/PowerPC/PPCFrameLowering.cpp

Lines changed: 2 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -1441,8 +1441,7 @@ void PPCFrameLowering::inlineStackProbe(MachineFunction &MF,
14411441
ProbeLoopBodyMBB->addSuccessor(ProbeLoopBodyMBB);
14421442
}
14431443
// Update liveins.
1444-
recomputeLiveIns(*ProbeLoopBodyMBB);
1445-
recomputeLiveIns(*ProbeExitMBB);
1444+
recomputeLiveIns(MF);
14461445
return ProbeExitMBB;
14471446
};
14481447
// For case HasBP && MaxAlign > 1, we have to realign the SP by performing
@@ -1534,8 +1533,7 @@ void PPCFrameLowering::inlineStackProbe(MachineFunction &MF,
15341533
buildDefCFAReg(*ExitMBB, ExitMBB->begin(), SPReg);
15351534
}
15361535
// Update liveins.
1537-
recomputeLiveIns(*LoopMBB);
1538-
recomputeLiveIns(*ExitMBB);
1536+
recomputeLiveIns(MF);
15391537
}
15401538
}
15411539
++NumPrologProbed;

‎llvm/lib/Target/SystemZ/SystemZFrameLowering.cpp

Lines changed: 2 additions & 4 deletions
Original file line numberDiff line numberDiff line change
@@ -840,8 +840,7 @@ void SystemZELFFrameLowering::inlineStackProbe(
840840
StackAllocMI->eraseFromParent();
841841
if (DoneMBB != nullptr) {
842842
// Compute the live-in lists for the new blocks.
843-
recomputeLiveIns(*DoneMBB);
844-
recomputeLiveIns(*LoopMBB);
843+
recomputeLiveIns(MF);
845844
}
846845
}
847846

@@ -1439,8 +1438,7 @@ void SystemZXPLINKFrameLowering::inlineStackProbe(
14391438
StackAllocMI->eraseFromParent();
14401439

14411440
// Compute the live-in lists for the new blocks.
1442-
recomputeLiveIns(*NextMBB);
1443-
recomputeLiveIns(*StackExtMBB);
1441+
recomputeLiveIns(MF);
14441442
}
14451443

14461444
bool SystemZXPLINKFrameLowering::hasFP(const MachineFunction &MF) const {

‎llvm/lib/Target/X86/X86FrameLowering.cpp

Lines changed: 2 additions & 6 deletions
Original file line numberDiff line numberDiff line change
@@ -885,8 +885,7 @@ void X86FrameLowering::emitStackProbeInlineGenericLoop(
885885
}
886886

887887
// Update Live In information
888-
recomputeLiveIns(*testMBB);
889-
recomputeLiveIns(*tailMBB);
888+
recomputeLiveIns(MF);
890889
}
891890

892891
void X86FrameLowering::emitStackProbeInlineWindowsCoreCLR64(
@@ -1378,10 +1377,7 @@ void X86FrameLowering::BuildStackAlignAND(MachineBasicBlock &MBB,
13781377
footMBB->addSuccessor(&MBB);
13791378
}
13801379

1381-
recomputeLiveIns(*headMBB);
1382-
recomputeLiveIns(*bodyMBB);
1383-
recomputeLiveIns(*footMBB);
1384-
recomputeLiveIns(MBB);
1380+
recomputeLiveIns(MF);
13851381
}
13861382
} else {
13871383
MachineInstr *MI = BuildMI(MBB, MBBI, DL, TII.get(AndOp), Reg)

‎llvm/test/CodeGen/AArch64/stack-probing-last-in-block.mir

Lines changed: 1 addition & 1 deletion
Original file line numberDiff line numberDiff line change
@@ -82,7 +82,7 @@ body: |
8282
; CHECK-LABEL: name: f
8383
; CHECK: bb.0.entry:
8484
; CHECK-NEXT: successors: %bb.3(0x80000000)
85-
; CHECK-NEXT: liveins: $lr, $fp
85+
; CHECK-NEXT: liveins: $fp, $lr
8686
; CHECK-NEXT: {{ $}}
8787
; CHECK-NEXT: early-clobber $sp = frame-setup STPXpre killed $fp, killed $lr, $sp, -2 :: (store (s64) into %stack.2), (store (s64) into %stack.1)
8888
; CHECK-NEXT: frame-setup CFI_INSTRUCTION def_cfa_offset 16

‎llvm/test/CodeGen/SystemZ/branch-folder-hoist-livein.mir

Lines changed: 25 additions & 11 deletions
Original file line numberDiff line numberDiff line change
@@ -1,3 +1,4 @@
1+
# NOTE: Assertions have been autogenerated by utils/update_mir_test_checks.py UTC_ARGS: --version 4
12
# RUN: llc -verify-machineinstrs -O1 -mtriple=s390x-ibm-linux -o - %s -run-pass=branch-folder | FileCheck %s
23
--- |
34
target datalayout = "E-m:e-i1:8:16-i8:8:16-i64:64-f128:64-a:8:16-n32:64"
@@ -15,6 +16,30 @@
1516
name: f1
1617
tracksRegLiveness: true
1718
body: |
19+
; CHECK-LABEL: name: f1
20+
; CHECK: bb.0:
21+
; CHECK-NEXT: successors: %bb.2(0x7fffffff), %bb.1(0x00000001)
22+
; CHECK-NEXT: {{ $}}
23+
; CHECK-NEXT: renamable $r1d = LGRL @b :: (load (s32) from got, align 8)
24+
; CHECK-NEXT: renamable $r1l = LH killed renamable $r1d, 0, $noreg, implicit-def $r1d :: (dereferenceable load (s8) from @b)
25+
; CHECK-NEXT: renamable $r2l = LHI 0
26+
; CHECK-NEXT: renamable $r3d = LGRL @d :: (load (s32) from got, align 8)
27+
; CHECK-NEXT: renamable $r4d = LLILL 0, implicit-def $r4q
28+
; CHECK-NEXT: renamable $r4d = COPY killed renamable $r4d, implicit killed $r4q
29+
; CHECK-NEXT: CHI killed renamable $r2l, 0, implicit-def $cc
30+
; CHECK-NEXT: BRC 14, 6, %bb.2, implicit killed $cc
31+
; CHECK-NEXT: {{ $}}
32+
; CHECK-NEXT: bb.1:
33+
; CHECK-NEXT: successors:
34+
; CHECK-NEXT: liveins: $r3d, $r4d, $r1l
35+
; CHECK-NEXT: {{ $}}
36+
; CHECK-NEXT: STH renamable $r1l, killed renamable $r3d, 0, $noreg, implicit killed $r4d :: (store (s8) into @d)
37+
; CHECK-NEXT: {{ $}}
38+
; CHECK-NEXT: bb.2:
39+
; CHECK-NEXT: liveins: $r3d, $r4d, $r1l
40+
; CHECK-NEXT: {{ $}}
41+
; CHECK-NEXT: STH renamable $r1l, killed renamable $r3d, 0, $noreg, implicit killed $r4d :: (store (s8) into @d)
42+
; CHECK-NEXT: Return
1843
bb.0:
1944
successors: %bb.2(0x7fffffff), %bb.1(0x00000001)
2045
liveins:
@@ -44,14 +69,3 @@ body: |
4469
Return
4570
4671
...
47-
48-
# CHECK: renamable $r4d = COPY killed renamable $r4d, implicit killed $r4q
49-
# CHECK-NEXT: CHI killed renamable $r2l, 0, implicit-def $cc
50-
# CHECK-NEXT: BRC 14, 6, %bb.2, implicit killed $cc
51-
# CHECK-NEXT: {{^ $}}
52-
# CHECK-NEXT: bb.1:
53-
# CHECK-NEXT: successors:
54-
# CHECK-NEXT: liveins: $r1l, $r3d, $r4d
55-
56-
# CHECK: bb.2:
57-
# CHECK-NEXT: liveins: $r1l, $r3d, $r4d

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