From 2b066988909948dc3d53d01760bc2d71d32f3feb Mon Sep 17 00:00:00 2001
From: dim <dim@FreeBSD.org>
Date: Mon, 2 May 2011 19:34:44 +0000
Subject: Vendor import of llvm trunk r130700:
http://llvm.org/svn/llvm-project/llvm/trunk@130700
---
lib/CodeGen/VirtRegRewriter.cpp | 53 +++++++++++++++++++++++++++++++----------
1 file changed, 41 insertions(+), 12 deletions(-)
(limited to 'lib/CodeGen/VirtRegRewriter.cpp')
diff --git a/lib/CodeGen/VirtRegRewriter.cpp b/lib/CodeGen/VirtRegRewriter.cpp
index ec149dd..1850658 100644
--- a/lib/CodeGen/VirtRegRewriter.cpp
+++ b/lib/CodeGen/VirtRegRewriter.cpp
@@ -32,7 +32,7 @@ STATISTIC(NumCommutes, "Number of instructions commuted");
STATISTIC(NumDRM , "Number of re-materializable defs elided");
STATISTIC(NumStores , "Number of stores added");
STATISTIC(NumPSpills , "Number of physical register spills");
-STATISTIC(NumOmitted , "Number of reloads omited");
+STATISTIC(NumOmitted , "Number of reloads omitted");
STATISTIC(NumAvoided , "Number of reloads deemed unnecessary");
STATISTIC(NumCopified, "Number of available reloads turned into copies");
STATISTIC(NumReMats , "Number of re-materialization");
@@ -261,6 +261,10 @@ public:
/// now).
void ModifyStackSlotOrReMat(int SlotOrReMat);
+ /// ClobberSharingStackSlots - When a register mapped to a stack slot changes,
+ /// other stack slots sharing the same register are no longer valid.
+ void ClobberSharingStackSlots(int StackSlot);
+
/// AddAvailableRegsToLiveIn - Availability information is being kept coming
/// into the specified MBB. Add available physical registers as potential
/// live-in's. If they are reused in the MBB, they will be added to the
@@ -665,7 +669,7 @@ static void UpdateKills(MachineInstr &MI, const TargetRegisterInfo* TRI,
}
}
-/// ReMaterialize - Re-materialize definition for Reg targetting DestReg.
+/// ReMaterialize - Re-materialize definition for Reg targeting DestReg.
///
static void ReMaterialize(MachineBasicBlock &MBB,
MachineBasicBlock::iterator &MII,
@@ -831,6 +835,26 @@ void AvailableSpills::ModifyStackSlotOrReMat(int SlotOrReMat) {
PhysRegsAvailable.erase(I);
}
+void AvailableSpills::ClobberSharingStackSlots(int StackSlot) {
+ std::map<int, unsigned>::iterator It =
+ SpillSlotsOrReMatsAvailable.find(StackSlot);
+ if (It == SpillSlotsOrReMatsAvailable.end()) return;
+ unsigned Reg = It->second >> 1;
+
+ // Erase entries in PhysRegsAvailable for other stack slots.
+ std::multimap<unsigned, int>::iterator I = PhysRegsAvailable.lower_bound(Reg);
+ while (I != PhysRegsAvailable.end() && I->first == Reg) {
+ std::multimap<unsigned, int>::iterator NextI = llvm::next(I);
+ if (I->second != StackSlot) {
+ DEBUG(dbgs() << "Clobbered sharing SS#" << I->second << " in "
+ << PrintReg(Reg, TRI) << '\n');
+ SpillSlotsOrReMatsAvailable.erase(I->second);
+ PhysRegsAvailable.erase(I);
+ }
+ I = NextI;
+ }
+}
+
// ************************** //
// Reuse Info Implementation //
// ************************** //
@@ -1791,8 +1815,8 @@ bool LocalRewriter::InsertRestores(MachineInstr *MI,
else
DEBUG(dbgs() << "Reusing SS#" << SSorRMId);
DEBUG(dbgs() << " from physreg "
- << TRI->getName(InReg) << " for vreg"
- << VirtReg <<" instead of reloading into physreg "
+ << TRI->getName(InReg) << " for " << PrintReg(VirtReg)
+ <<" instead of reloading into physreg "
<< TRI->getName(Phys) << '\n');
// Reusing a physreg may resurrect it. But we expect ProcessUses to update
@@ -1807,8 +1831,8 @@ bool LocalRewriter::InsertRestores(MachineInstr *MI,
else
DEBUG(dbgs() << "Reusing SS#" << SSorRMId);
DEBUG(dbgs() << " from physreg "
- << TRI->getName(InReg) << " for vreg"
- << VirtReg <<" by copying it into physreg "
+ << TRI->getName(InReg) << " for " << PrintReg(VirtReg)
+ <<" by copying it into physreg "
<< TRI->getName(Phys) << '\n');
// If the reloaded / remat value is available in another register,
@@ -2025,7 +2049,8 @@ void LocalRewriter::ProcessUses(MachineInstr &MI, AvailableSpills &Spills,
TRI->regsOverlap(MOk.getReg(), PhysReg)) {
CanReuse = false;
DEBUG(dbgs() << "Not reusing physreg " << TRI->getName(PhysReg)
- << " for vreg" << VirtReg << ": " << MOk << '\n');
+ << " for " << PrintReg(VirtReg) << ": " << MOk
+ << '\n');
break;
}
}
@@ -2039,9 +2064,9 @@ void LocalRewriter::ProcessUses(MachineInstr &MI, AvailableSpills &Spills,
else
DEBUG(dbgs() << "Reusing SS#" << ReuseSlot);
DEBUG(dbgs() << " from physreg "
- << TRI->getName(PhysReg) << " for vreg"
- << VirtReg <<" instead of reloading into physreg "
- << TRI->getName(VRM->getPhys(VirtReg)) << '\n');
+ << TRI->getName(PhysReg) << " for " << PrintReg(VirtReg)
+ << " instead of reloading into "
+ << PrintReg(VRM->getPhys(VirtReg), TRI) << '\n');
unsigned RReg = SubIdx ? TRI->getSubReg(PhysReg, SubIdx) : PhysReg;
MI.getOperand(i).setReg(RReg);
MI.getOperand(i).setSubReg(0);
@@ -2126,7 +2151,7 @@ void LocalRewriter::ProcessUses(MachineInstr &MI, AvailableSpills &Spills,
else
DEBUG(dbgs() << "Reusing SS#" << ReuseSlot);
DEBUG(dbgs() << " from physreg " << TRI->getName(PhysReg)
- << " for vreg" << VirtReg
+ << " for " << PrintReg(VirtReg)
<< " instead of reloading into same physreg.\n");
unsigned RReg = SubIdx ? TRI->getSubReg(PhysReg, SubIdx) : PhysReg;
MI.getOperand(i).setReg(RReg);
@@ -2315,7 +2340,7 @@ LocalRewriter::RewriteMBB(LiveIntervals *LIs,
for (unsigned FVI = 0, FVE = FoldedVirts.size(); FVI != FVE; ++FVI) {
unsigned VirtReg = FoldedVirts[FVI].first;
VirtRegMap::ModRef MR = FoldedVirts[FVI].second;
- DEBUG(dbgs() << "Folded vreg: " << VirtReg << " MR: " << MR);
+ DEBUG(dbgs() << "Folded " << PrintReg(VirtReg) << " MR: " << MR);
int SS = VRM->getStackSlot(VirtReg);
if (SS == VirtRegMap::NO_STACK_SLOT)
@@ -2549,6 +2574,10 @@ LocalRewriter::RewriteMBB(LiveIntervals *LIs,
}
}
+ // If StackSlot is available in a register that also holds other stack
+ // slots, clobber those stack slots now.
+ Spills.ClobberSharingStackSlots(StackSlot);
+
assert(PhysReg && "VR not assigned a physical register?");
MRI->setPhysRegUsed(PhysReg);
unsigned RReg = SubIdx ? TRI->getSubReg(PhysReg, SubIdx) : PhysReg;
--
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