[llvm] [llvm][CodeGen] Fix the issue caused by live interval checking in window scheduler (PR #123184)
Hua Tian via llvm-commits
llvm-commits at lists.llvm.org
Fri Jan 17 00:05:19 PST 2025
https://github.com/huaatian updated https://github.com/llvm/llvm-project/pull/123184
>From 507d47c50e491cdaa56846f7265d8291a49bc4c9 Mon Sep 17 00:00:00 2001
From: akiratian <akiratian at tencent.com>
Date: Thu, 16 Jan 2025 19:06:49 +0800
Subject: [PATCH 1/3] [llvm][CodeGen] Fix the issue caused by live interval
checking in window scheduler
At some corner cases, the cloned MI still retains a random slot index,
which leads to the compiler crashing. Therefore, when we repair the slot
index of the newly cloned MI, we first clear it.
https://github.com/llvm/llvm-project/issues/123165
---
llvm/lib/CodeGen/WindowScheduler.cpp | 5 +-
.../Hexagon/swp-ws-live-intervals-1.mir | 61 +++++++++++++++++++
2 files changed, 65 insertions(+), 1 deletion(-)
create mode 100644 llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
diff --git a/llvm/lib/CodeGen/WindowScheduler.cpp b/llvm/lib/CodeGen/WindowScheduler.cpp
index f1658e36ae1e92..56e92ff9bde7f5 100644
--- a/llvm/lib/CodeGen/WindowScheduler.cpp
+++ b/llvm/lib/CodeGen/WindowScheduler.cpp
@@ -645,7 +645,7 @@ void WindowScheduler::expand() {
void WindowScheduler::updateLiveIntervals() {
SmallVector<Register, 128> UsedRegs;
- for (MachineInstr &MI : *MBB)
+ for (MachineInstr &MI : *MBB) {
for (const MachineOperand &MO : MI.operands()) {
if (!MO.isReg() || MO.getReg() == 0)
continue;
@@ -653,6 +653,9 @@ void WindowScheduler::updateLiveIntervals() {
if (!is_contained(UsedRegs, Reg))
UsedRegs.push_back(Reg);
}
+ // Remove the residual slot index of newly cloned MI.
+ Context->LIS->getSlotIndexes()->removeMachineInstrFromMaps(MI, true);
+ }
Context->LIS->repairIntervalsInRange(MBB, MBB->begin(), MBB->end(), UsedRegs);
}
diff --git a/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir b/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
new file mode 100644
index 00000000000000..ae5e10b1eee1ff
--- /dev/null
+++ b/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
@@ -0,0 +1,61 @@
+# REQUIRES: asserts
+#
+# RUN: llc --mtriple=hexagon %s -run-pass=pipeliner -debug-only=pipeliner \
+# RUN: -window-sched=force -filetype=null -verify-machineinstrs 2>&1\
+# RUN: | FileCheck %s
+
+# The bug was reported at https://github.com/llvm/llvm-project/issues/123165.
+# It is caused by the corruption of live intervals in certain scenarios.
+#
+# We check window scheduling logs to ensure that there is no crashing.
+# CHECK: Start analyzing II:
+# CHECK: MaxCycle is {{[0-9]+}}.
+# CHECK: MaxStallCycle is {{[0-9]+}}.
+# CHECK: Start scheduling Phis:
+# CHECK: Current window Offset is {{[0-9]+}} and II is {{[0-9]+}}.
+# CHECK: Window scheduling is not needed!
+
+...
+---
+name: _ZN10CInArchive17GetNextFolderItemEv
+tracksRegLiveness: true
+body: |
+ bb.0:
+ successors: %bb.1(0x80000000)
+ liveins: $r0
+
+ %0:intregs = COPY $r0
+ J2_loop0i %bb.1, 1, implicit-def $lc0, implicit-def $sa0, implicit-def $usr
+
+ bb.1:
+ successors: %bb.2(0x04000000), %bb.1(0x7c000000)
+
+ %1:intregs = L2_loadri_io %0, 0
+ %2:intregs = L2_loadrub_io killed %1, 0
+ %3:intregs = PS_loadriabs 0
+ S2_storerb_io killed %3, 0, killed %2
+ ENDLOOP0 %bb.1, implicit-def $pc, implicit-def $lc0, implicit $sa0, implicit $lc0
+
+ bb.2:
+ successors: %bb.4(0x80000000)
+
+ %4:intregs = A2_tfrsi 0
+ %5:intregs = A2_tfrsi -1
+ J2_loop0i %bb.4, 1, implicit-def $lc0, implicit-def $sa0, implicit-def $usr
+ J2_jump %bb.4, implicit-def $pc
+
+ bb.3:
+ S2_storeri_io %0, 0, %6
+ PS_jmpret $r31, implicit-def dead $pc
+
+ bb.4:
+ successors: %bb.3(0x04000000), %bb.4(0x7c000000)
+
+ %7:intregs = PHI %5, %bb.2, %8, %bb.4
+ %6:intregs = PHI %4, %bb.2, %9, %bb.4
+ %8:intregs = A2_addi %7, 1
+ %9:intregs = S2_setbit_i %8, 0
+ ENDLOOP0 %bb.4, implicit-def $pc, implicit-def $lc0, implicit $sa0, implicit $lc0
+ J2_jump %bb.3, implicit-def $pc
+
+...
>From 67b12ae722c2ce4edbae8103c6443a7c21a608e7 Mon Sep 17 00:00:00 2001
From: akiratian <akiratian at tencent.com>
Date: Fri, 17 Jan 2025 10:24:43 +0800
Subject: [PATCH 2/3] [llvm][CodeGen] Modifications made based on review
comments 1
---
llvm/lib/CodeGen/WindowScheduler.cpp | 6 +++---
llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir | 2 +-
2 files changed, 4 insertions(+), 4 deletions(-)
diff --git a/llvm/lib/CodeGen/WindowScheduler.cpp b/llvm/lib/CodeGen/WindowScheduler.cpp
index 56e92ff9bde7f5..2177afcfab3ea1 100644
--- a/llvm/lib/CodeGen/WindowScheduler.cpp
+++ b/llvm/lib/CodeGen/WindowScheduler.cpp
@@ -270,7 +270,7 @@ void WindowScheduler::backupMBB() {
OriMIs.push_back(&MI);
// Remove MIs and the corresponding live intervals.
for (auto &MI : make_early_inc_range(*MBB)) {
- Context->LIS->getSlotIndexes()->removeMachineInstrFromMaps(MI, true);
+ Context->LIS->RemoveMachineInstrFromMaps(MI);
MBB->remove(&MI);
}
}
@@ -278,7 +278,7 @@ void WindowScheduler::backupMBB() {
void WindowScheduler::restoreMBB() {
// Erase MIs and the corresponding live intervals.
for (auto &MI : make_early_inc_range(*MBB)) {
- Context->LIS->getSlotIndexes()->removeMachineInstrFromMaps(MI, true);
+ Context->LIS->RemoveMachineInstrFromMaps(MI);
MI.eraseFromParent();
}
// Restore MBB to the state before window scheduling.
@@ -654,7 +654,7 @@ void WindowScheduler::updateLiveIntervals() {
UsedRegs.push_back(Reg);
}
// Remove the residual slot index of newly cloned MI.
- Context->LIS->getSlotIndexes()->removeMachineInstrFromMaps(MI, true);
+ Context->LIS->RemoveMachineInstrFromMaps(MI);
}
Context->LIS->repairIntervalsInRange(MBB, MBB->begin(), MBB->end(), UsedRegs);
}
diff --git a/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir b/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
index ae5e10b1eee1ff..c43fce5707de88 100644
--- a/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
+++ b/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
@@ -1,7 +1,7 @@
# REQUIRES: asserts
#
# RUN: llc --mtriple=hexagon %s -run-pass=pipeliner -debug-only=pipeliner \
-# RUN: -window-sched=force -filetype=null -verify-machineinstrs 2>&1\
+# RUN: -window-sched=force -filetype=null 2>&1\
# RUN: | FileCheck %s
# The bug was reported at https://github.com/llvm/llvm-project/issues/123165.
>From 4f103fc9396958febcbd7f97a1d26c7c35ca6c89 Mon Sep 17 00:00:00 2001
From: akiratian <akiratian at tencent.com>
Date: Fri, 17 Jan 2025 16:04:03 +0800
Subject: [PATCH 3/3] [llvm][CodeGen] Modifications made based on review
comments 2
---
llvm/lib/CodeGen/WindowScheduler.cpp | 4 ++--
llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir | 3 +--
2 files changed, 3 insertions(+), 4 deletions(-)
diff --git a/llvm/lib/CodeGen/WindowScheduler.cpp b/llvm/lib/CodeGen/WindowScheduler.cpp
index 2177afcfab3ea1..a329eaa24dab32 100644
--- a/llvm/lib/CodeGen/WindowScheduler.cpp
+++ b/llvm/lib/CodeGen/WindowScheduler.cpp
@@ -303,6 +303,7 @@ void WindowScheduler::generateTripleMBB() {
if (Register AntiReg = getAntiRegister(MI))
DefPairs[MI->getOperand(0).getReg()] = AntiReg;
auto *NewMI = MF->CloneMachineInstr(MI);
+ Context->LIS->RemoveMachineInstrFromMaps(*NewMI);
MBB->push_back(NewMI);
TriMIs.push_back(NewMI);
TriToOri[NewMI] = MI;
@@ -316,6 +317,7 @@ void WindowScheduler::generateTripleMBB() {
(MI->isTerminator() && Cnt < DuplicateNum - 1))
continue;
auto *NewMI = MF->CloneMachineInstr(MI);
+ Context->LIS->RemoveMachineInstrFromMaps(*NewMI);
DenseMap<Register, Register> NewDefs;
// New defines are updated.
for (auto MO : NewMI->all_defs())
@@ -653,8 +655,6 @@ void WindowScheduler::updateLiveIntervals() {
if (!is_contained(UsedRegs, Reg))
UsedRegs.push_back(Reg);
}
- // Remove the residual slot index of newly cloned MI.
- Context->LIS->RemoveMachineInstrFromMaps(MI);
}
Context->LIS->repairIntervalsInRange(MBB, MBB->begin(), MBB->end(), UsedRegs);
}
diff --git a/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir b/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
index c43fce5707de88..560503ac379233 100644
--- a/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
+++ b/llvm/test/CodeGen/Hexagon/swp-ws-live-intervals-1.mir
@@ -1,8 +1,7 @@
# REQUIRES: asserts
#
# RUN: llc --mtriple=hexagon %s -run-pass=pipeliner -debug-only=pipeliner \
-# RUN: -window-sched=force -filetype=null 2>&1\
-# RUN: | FileCheck %s
+# RUN: -filetype=null 2>&1 | FileCheck %s
# The bug was reported at https://github.com/llvm/llvm-project/issues/123165.
# It is caused by the corruption of live intervals in certain scenarios.
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