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-rw-r--r--lib/CodeGen/SplitKit.cpp64
-rw-r--r--lib/CodeGen/SplitKit.h16
2 files changed, 26 insertions, 54 deletions
diff --git a/lib/CodeGen/SplitKit.cpp b/lib/CodeGen/SplitKit.cpp
index 0b59a28c06..4b642883d4 100644
--- a/lib/CodeGen/SplitKit.cpp
+++ b/lib/CodeGen/SplitKit.cpp
@@ -21,7 +21,6 @@
#include "llvm/CodeGen/MachineDominators.h"
#include "llvm/CodeGen/MachineInstrBuilder.h"
#include "llvm/CodeGen/MachineRegisterInfo.h"
-#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetInstrInfo.h"
@@ -29,10 +28,6 @@
using namespace llvm;
-static cl::opt<bool>
-AllowSplit("spiller-splits-edges",
- cl::desc("Allow critical edge splitting during spilling"));
-
STATISTIC(NumFinished, "Number of splits finished");
STATISTIC(NumSimple, "Number of splits that were simple");
@@ -53,8 +48,6 @@ SplitAnalysis::SplitAnalysis(const VirtRegMap &vrm,
void SplitAnalysis::clear() {
UseSlots.clear();
- UsingInstrs.clear();
- UsingBlocks.clear();
LiveBlocks.clear();
CurLI = 0;
}
@@ -96,21 +89,31 @@ SlotIndex SplitAnalysis::computeLastSplitPoint(unsigned Num) {
/// analyzeUses - Count instructions, basic blocks, and loops using CurLI.
void SplitAnalysis::analyzeUses() {
+ assert(UseSlots.empty() && "Call clear first");
+
+ // First get all the defs from the interval values. This provides the correct
+ // slots for early clobbers.
+ for (LiveInterval::const_vni_iterator I = CurLI->vni_begin(),
+ E = CurLI->vni_end(); I != E; ++I)
+ if (!(*I)->isPHIDef() && !(*I)->isUnused())
+ UseSlots.push_back((*I)->def);
+
+ // Get use slots form the use-def chain.
const MachineRegisterInfo &MRI = MF.getRegInfo();
- for (MachineRegisterInfo::reg_iterator I = MRI.reg_begin(CurLI->reg),
- E = MRI.reg_end(); I != E; ++I) {
- MachineOperand &MO = I.getOperand();
- if (MO.isUse() && MO.isUndef())
- continue;
- MachineInstr *MI = MO.getParent();
- if (MI->isDebugValue() || !UsingInstrs.insert(MI))
- continue;
- UseSlots.push_back(LIS.getInstructionIndex(MI).getDefIndex());
- MachineBasicBlock *MBB = MI->getParent();
- UsingBlocks[MBB]++;
- }
+ for (MachineRegisterInfo::use_nodbg_iterator
+ I = MRI.use_nodbg_begin(CurLI->reg), E = MRI.use_nodbg_end(); I != E;
+ ++I)
+ if (!I.getOperand().isUndef())
+ UseSlots.push_back(LIS.getInstructionIndex(&*I).getDefIndex());
+
array_pod_sort(UseSlots.begin(), UseSlots.end());
+ // Remove duplicates, keeping the smaller slot for each instruction.
+ // That is what we want for early clobbers.
+ UseSlots.erase(std::unique(UseSlots.begin(), UseSlots.end(),
+ SlotIndex::isSameInstr),
+ UseSlots.end());
+
// Compute per-live block info.
if (!calcLiveBlockInfo()) {
// FIXME: calcLiveBlockInfo found inconsistencies in the live range.
@@ -125,8 +128,7 @@ void SplitAnalysis::analyzeUses() {
}
DEBUG(dbgs() << "Analyze counted "
- << UsingInstrs.size() << " instrs, "
- << UsingBlocks.size() << " blocks, "
+ << UseSlots.size() << " instrs, "
<< LiveBlocks.size() << " spanned.\n");
}
@@ -157,8 +159,8 @@ bool SplitAnalysis::calcLiveBlockInfo() {
BI.Def = LVI->start;
// Find the first and last uses in the block.
- BI.Uses = hasUses(MFI);
- if (BI.Uses && UseI != UseE) {
+ BI.Uses = UseI != UseE && *UseI < Stop;
+ if (BI.Uses) {
BI.FirstUse = *UseI;
assert(BI.FirstUse >= Start);
do ++UseI;
@@ -224,15 +226,6 @@ bool SplitAnalysis::isOriginalEndpoint(SlotIndex Idx) const {
return I != Orig.begin() && (--I)->end == Idx;
}
-void SplitAnalysis::print(const BlockPtrSet &B, raw_ostream &OS) const {
- for (BlockPtrSet::const_iterator I = B.begin(), E = B.end(); I != E; ++I) {
- unsigned count = UsingBlocks.lookup(*I);
- OS << " BB#" << (*I)->getNumber();
- if (count)
- OS << '(' << count << ')';
- }
-}
-
void SplitAnalysis::analyze(const LiveInterval *li) {
clear();
CurLI = li;
@@ -918,12 +911,7 @@ bool SplitAnalysis::getMultiUseBlocks(BlockPtrSet &Blocks) {
// Add blocks with multiple uses.
for (unsigned i = 0, e = LiveBlocks.size(); i != e; ++i) {
const BlockInfo &BI = LiveBlocks[i];
- if (!BI.Uses)
- continue;
- unsigned Instrs = UsingBlocks.lookup(BI.MBB);
- if (Instrs <= 1)
- continue;
- if (Instrs == 2 && BI.LiveIn && BI.LiveOut && !BI.LiveThrough)
+ if (!BI.Uses || BI.FirstUse == BI.LastUse)
continue;
Blocks.insert(BI.MBB);
}
diff --git a/lib/CodeGen/SplitKit.h b/lib/CodeGen/SplitKit.h
index 50f8dcfbd1..793989f7e3 100644
--- a/lib/CodeGen/SplitKit.h
+++ b/lib/CodeGen/SplitKit.h
@@ -50,17 +50,9 @@ public:
const MachineLoopInfo &Loops;
const TargetInstrInfo &TII;
- // Instructions using the the current register.
- typedef SmallPtrSet<const MachineInstr*, 16> InstrPtrSet;
- InstrPtrSet UsingInstrs;
-
// Sorted slot indexes of using instructions.
SmallVector<SlotIndex, 8> UseSlots;
- // The number of instructions using CurLI in each basic block.
- typedef DenseMap<const MachineBasicBlock*, unsigned> BlockCountMap;
- BlockCountMap UsingBlocks;
-
/// Additional information about basic blocks where the current variable is
/// live. Such a block will look like one of these templates:
///
@@ -130,11 +122,6 @@ public:
return computeLastSplitPoint(Num);
}
- /// hasUses - Return true if MBB has any uses of CurLI.
- bool hasUses(const MachineBasicBlock *MBB) const {
- return UsingBlocks.lookup(MBB);
- }
-
/// isOriginalEndpoint - Return true if the original live range was killed or
/// (re-)defined at Idx. Idx should be the 'def' slot for a normal kill/def,
/// and 'use' for an early-clobber def.
@@ -144,9 +131,6 @@ public:
typedef SmallPtrSet<const MachineBasicBlock*, 16> BlockPtrSet;
- // Print a set of blocks with use counts.
- void print(const BlockPtrSet&, raw_ostream&) const;
-
/// getMultiUseBlocks - Add basic blocks to Blocks that may benefit from
/// having CurLI split to a new live interval. Return true if Blocks can be
/// passed to SplitEditor::splitSingleBlocks.
generated by cgit v1.2.3 (git 2.25.1) at 2024-06-12 03:32:45 +0000