diff options
-rw-r--r-- | lib/CodeGen/SimpleRegisterCoalescing.cpp | 148 | ||||
-rw-r--r-- | lib/CodeGen/SimpleRegisterCoalescing.h | 13 | ||||
-rw-r--r-- | test/CodeGen/ARM/2008-11-19-ScavengerAssert.ll | 2 | ||||
-rw-r--r-- | test/CodeGen/ARM/remat.ll | 2 | ||||
-rw-r--r-- | test/CodeGen/X86/2008-02-22-ReMatBug.ll | 3 | ||||
-rw-r--r-- | test/CodeGen/X86/2008-07-11-SpillerBug.ll | 3 | ||||
-rw-r--r-- | test/CodeGen/X86/2009-04-20-LinearScanOpt.ll | 2 | ||||
-rw-r--r-- | test/CodeGen/X86/2009-09-21-NoSpillLoopCount.ll | 36 | ||||
-rw-r--r-- | test/CodeGen/X86/stack-color-with-reg.ll | 4 |
9 files changed, 145 insertions, 68 deletions
diff --git a/lib/CodeGen/SimpleRegisterCoalescing.cpp b/lib/CodeGen/SimpleRegisterCoalescing.cpp index bbb742678f..068dcda93b 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.cpp +++ b/lib/CodeGen/SimpleRegisterCoalescing.cpp @@ -2535,7 +2535,8 @@ void SimpleRegisterCoalescing::releaseMemory() { ReMatDefs.clear(); } -bool SimpleRegisterCoalescing::isZeroLengthInterval(LiveInterval *li) const { +/// Returns true if the given live interval is zero length. +static bool isZeroLengthInterval(LiveInterval *li, LiveIntervals *li_) { for (LiveInterval::Ranges::const_iterator i = li->ranges.begin(), e = li->ranges.end(); i != e; ++i) if (li_->getPrevIndex(i->end) > i->start) @@ -2543,6 +2544,97 @@ bool SimpleRegisterCoalescing::isZeroLengthInterval(LiveInterval *li) const { return true; } +void SimpleRegisterCoalescing::CalculateSpillWeights() { + SmallSet<unsigned, 4> Processed; + for (MachineFunction::iterator mbbi = mf_->begin(), mbbe = mf_->end(); + mbbi != mbbe; ++mbbi) { + MachineBasicBlock* MBB = mbbi; + MachineInstrIndex MBBEnd = li_->getMBBEndIdx(MBB); + MachineLoop* loop = loopInfo->getLoopFor(MBB); + unsigned loopDepth = loop ? loop->getLoopDepth() : 0; + bool isExit = loop ? loop->isLoopExit(MBB) : false; + + for (MachineBasicBlock::iterator mii = MBB->begin(), mie = MBB->end(); + mii != mie; ++mii) { + MachineInstr *MI = mii; + + for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { + const MachineOperand &mopi = MI->getOperand(i); + if (!mopi.isReg() || mopi.getReg() == 0) + continue; + unsigned Reg = mopi.getReg(); + if (!TargetRegisterInfo::isVirtualRegister(mopi.getReg())) + continue; + // Multiple uses of reg by the same instruction. It should not + // contribute to spill weight again. + if (!Processed.insert(Reg)) + continue; + + bool HasDef = mopi.isDef(); + bool HasUse = mopi.isUse(); + for (unsigned j = i+1; j != e; ++j) { + const MachineOperand &mopj = MI->getOperand(j); + if (!mopj.isReg() || mopj.getReg() != Reg) + continue; + HasDef |= mopj.isDef(); + HasUse |= mopj.isUse(); + } + + LiveInterval &RegInt = li_->getInterval(Reg); + float Weight = li_->getSpillWeight(HasDef, HasUse, loopDepth+1); + if (HasDef && isExit) { + // Looks like this is a loop count variable update. + MachineInstrIndex DefIdx = + li_->getDefIndex(li_->getInstructionIndex(MI)); + const LiveRange *DLR = + li_->getInterval(Reg).getLiveRangeContaining(DefIdx); + if (DLR->end > MBBEnd) + Weight *= 3.0F; + } + RegInt.weight += Weight; + } + Processed.clear(); + } + } + + for (LiveIntervals::iterator I = li_->begin(), E = li_->end(); I != E; ++I) { + LiveInterval &LI = *I->second; + if (TargetRegisterInfo::isVirtualRegister(LI.reg)) { + // If the live interval length is essentially zero, i.e. in every live + // range the use follows def immediately, it doesn't make sense to spill + // it and hope it will be easier to allocate for this li. + if (isZeroLengthInterval(&LI, li_)) { + LI.weight = HUGE_VALF; + continue; + } + + bool isLoad = false; + SmallVector<LiveInterval*, 4> SpillIs; + if (li_->isReMaterializable(LI, SpillIs, isLoad)) { + // If all of the definitions of the interval are re-materializable, + // it is a preferred candidate for spilling. If non of the defs are + // loads, then it's potentially very cheap to re-materialize. + // FIXME: this gets much more complicated once we support non-trivial + // re-materialization. + if (isLoad) + LI.weight *= 0.9F; + else + LI.weight *= 0.5F; + } + + // Slightly prefer live interval that has been assigned a preferred reg. + std::pair<unsigned, unsigned> Hint = mri_->getRegAllocationHint(LI.reg); + if (Hint.first || Hint.second) + LI.weight *= 1.01F; + + // Divide the weight of the interval by its size. This encourages + // spilling of intervals that are large and have few uses, and + // discourages spilling of small intervals with many uses. + LI.weight /= li_->getApproximateInstructionCount(LI) * InstrSlots::NUM; + } + } +} + bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) { mf_ = &fn; @@ -2581,8 +2673,6 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) { for (MachineFunction::iterator mbbi = mf_->begin(), mbbe = mf_->end(); mbbi != mbbe; ++mbbi) { MachineBasicBlock* mbb = mbbi; - unsigned loopDepth = loopInfo->getLoopDepth(mbb); - for (MachineBasicBlock::iterator mii = mbb->begin(), mie = mbb->end(); mii != mie; ) { MachineInstr *MI = mii; @@ -2656,62 +2746,12 @@ bool SimpleRegisterCoalescing::runOnMachineFunction(MachineFunction &fn) { mii = mbbi->erase(mii); ++numPeep; } else { - SmallSet<unsigned, 4> UniqueUses; - for (unsigned i = 0, e = MI->getNumOperands(); i != e; ++i) { - const MachineOperand &mop = MI->getOperand(i); - if (mop.isReg() && mop.getReg() && - TargetRegisterInfo::isVirtualRegister(mop.getReg())) { - unsigned reg = mop.getReg(); - // Multiple uses of reg by the same instruction. It should not - // contribute to spill weight again. - if (UniqueUses.count(reg) != 0) - continue; - LiveInterval &RegInt = li_->getInterval(reg); - RegInt.weight += - li_->getSpillWeight(mop.isDef(), mop.isUse(), loopDepth); - UniqueUses.insert(reg); - } - } ++mii; } } } - for (LiveIntervals::iterator I = li_->begin(), E = li_->end(); I != E; ++I) { - LiveInterval &LI = *I->second; - if (TargetRegisterInfo::isVirtualRegister(LI.reg)) { - // If the live interval length is essentially zero, i.e. in every live - // range the use follows def immediately, it doesn't make sense to spill - // it and hope it will be easier to allocate for this li. - if (isZeroLengthInterval(&LI)) - LI.weight = HUGE_VALF; - else { - bool isLoad = false; - SmallVector<LiveInterval*, 4> SpillIs; - if (li_->isReMaterializable(LI, SpillIs, isLoad)) { - // If all of the definitions of the interval are re-materializable, - // it is a preferred candidate for spilling. If non of the defs are - // loads, then it's potentially very cheap to re-materialize. - // FIXME: this gets much more complicated once we support non-trivial - // re-materialization. - if (isLoad) - LI.weight *= 0.9F; - else - LI.weight *= 0.5F; - } - } - - // Slightly prefer live interval that has been assigned a preferred reg. - std::pair<unsigned, unsigned> Hint = mri_->getRegAllocationHint(LI.reg); - if (Hint.first || Hint.second) - LI.weight *= 1.01F; - - // Divide the weight of the interval by its size. This encourages - // spilling of intervals that are large and have few uses, and - // discourages spilling of small intervals with many uses. - LI.weight /= li_->getApproximateInstructionCount(LI) * InstrSlots::NUM; - } - } + CalculateSpillWeights(); DEBUG(dump()); return true; diff --git a/lib/CodeGen/SimpleRegisterCoalescing.h b/lib/CodeGen/SimpleRegisterCoalescing.h index 7364767ab0..20b8eb2274 100644 --- a/lib/CodeGen/SimpleRegisterCoalescing.h +++ b/lib/CodeGen/SimpleRegisterCoalescing.h @@ -123,7 +123,6 @@ namespace llvm { /// classes. The registers may be either phys or virt regs. bool differingRegisterClasses(unsigned RegA, unsigned RegB) const; - /// AdjustCopiesBackFrom - We found a non-trivially-coalescable copy. If /// the source value number is defined by a copy from the destination reg /// see if we can merge these two destination reg valno# into a single @@ -235,13 +234,15 @@ namespace llvm { /// lastRegisterUse - Returns the last use of the specific register between /// cycles Start and End or NULL if there are no uses. - MachineOperand *lastRegisterUse(MachineInstrIndex Start, MachineInstrIndex End, - unsigned Reg, MachineInstrIndex &LastUseIdx) const; + MachineOperand *lastRegisterUse(MachineInstrIndex Start, + MachineInstrIndex End, unsigned Reg, + MachineInstrIndex &LastUseIdx) const; - void printRegName(unsigned reg) const; + /// CalculateSpillWeights - Compute spill weights for all virtual register + /// live intervals. + void CalculateSpillWeights(); - /// Returns true if the given live interval is zero length. - bool isZeroLengthInterval(LiveInterval *li) const; + void printRegName(unsigned reg) const; }; } // End llvm namespace diff --git a/test/CodeGen/ARM/2008-11-19-ScavengerAssert.ll b/test/CodeGen/ARM/2008-11-19-ScavengerAssert.ll index 311c855742..221a168cba 100644 --- a/test/CodeGen/ARM/2008-11-19-ScavengerAssert.ll +++ b/test/CodeGen/ARM/2008-11-19-ScavengerAssert.ll @@ -1,4 +1,4 @@ -; RUN: llc < %s -mtriple=arm-apple-darwin9 -stats |& grep asm-printer | grep 164 +; RUN: llc < %s -mtriple=arm-apple-darwin9 -stats |& grep asm-printer | grep 161 %"struct.Adv5::Ekin<3>" = type <{ i8 }> %"struct.Adv5::X::Energyflux<3>" = type { double } diff --git a/test/CodeGen/ARM/remat.ll b/test/CodeGen/ARM/remat.ll index 21d117aaf2..50da997ed4 100644 --- a/test/CodeGen/ARM/remat.ll +++ b/test/CodeGen/ARM/remat.ll @@ -1,5 +1,5 @@ ; RUN: llc < %s -mtriple=arm-apple-darwin -; RUN: llc < %s -mtriple=arm-apple-darwin -stats -info-output-file - | grep "Number of re-materialization" | grep 2 +; RUN: llc < %s -mtriple=arm-apple-darwin -stats -info-output-file - | grep "Number of re-materialization" | grep 5 %struct.CONTENTBOX = type { i32, i32, i32, i32, i32 } %struct.LOCBOX = type { i32, i32, i32, i32 } diff --git a/test/CodeGen/X86/2008-02-22-ReMatBug.ll b/test/CodeGen/X86/2008-02-22-ReMatBug.ll index 95df19ad1f..a91ac27f98 100644 --- a/test/CodeGen/X86/2008-02-22-ReMatBug.ll +++ b/test/CodeGen/X86/2008-02-22-ReMatBug.ll @@ -1,5 +1,4 @@ -; RUN: llc < %s -march=x86 -stats |& grep {Number of re-materialization} | grep 3 -; RUN: llc < %s -march=x86 -stats |& grep {Number of dead spill slots removed} +; RUN: llc < %s -march=x86 -stats |& grep {Number of re-materialization} | grep 2 ; rdar://5761454 %struct.quad_struct = type { i32, i32, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct*, %struct.quad_struct* } diff --git a/test/CodeGen/X86/2008-07-11-SpillerBug.ll b/test/CodeGen/X86/2008-07-11-SpillerBug.ll index 6f3019e78c..f75e605168 100644 --- a/test/CodeGen/X86/2008-07-11-SpillerBug.ll +++ b/test/CodeGen/X86/2008-07-11-SpillerBug.ll @@ -2,8 +2,9 @@ ; PR2536 -; CHECK: movw %ax +; CHECK: movw %cx ; CHECK-NEXT: andl $65534, % +; CHECK-NEXT: movl % ; CHECK-NEXT: movl $17 @g_5 = external global i16 ; <i16*> [#uses=2] diff --git a/test/CodeGen/X86/2009-04-20-LinearScanOpt.ll b/test/CodeGen/X86/2009-04-20-LinearScanOpt.ll index 9f11c4e58a..4d25b0f983 100644 --- a/test/CodeGen/X86/2009-04-20-LinearScanOpt.ll +++ b/test/CodeGen/X86/2009-04-20-LinearScanOpt.ll @@ -1,4 +1,4 @@ -; RUN: llc < %s -mtriple=x86_64-apple-darwin10.0 -relocation-model=pic -disable-fp-elim -stats |& grep {Number of registers downgraded} +; RUN: llc < %s -mtriple=x86_64-apple-darwin10.0 -relocation-model=pic -disable-fp-elim -stats |& grep asm-printer | grep 84 ; rdar://6802189 ; Test if linearscan is unfavoring registers for allocation to allow more reuse diff --git a/test/CodeGen/X86/2009-09-21-NoSpillLoopCount.ll b/test/CodeGen/X86/2009-09-21-NoSpillLoopCount.ll new file mode 100644 index 0000000000..80b883582c --- /dev/null +++ b/test/CodeGen/X86/2009-09-21-NoSpillLoopCount.ll @@ -0,0 +1,36 @@ +; RUN: llc < %s -mtriple=i386-apple-darwin10.0 -relocation-model=pic | FileCheck %s + +define void @dot(i16* nocapture %A, i32 %As, i16* nocapture %B, i32 %Bs, i16* nocapture %C, i32 %N) nounwind ssp { +; CHECK: dot: +; CHECK: decl % +; CHECK-NEXT: jne +entry: + %0 = icmp sgt i32 %N, 0 ; <i1> [#uses=1] + br i1 %0, label %bb, label %bb2 + +bb: ; preds = %bb, %entry + %i.03 = phi i32 [ 0, %entry ], [ %indvar.next, %bb ] ; <i32> [#uses=3] + %sum.04 = phi i32 [ 0, %entry ], [ %10, %bb ] ; <i32> [#uses=1] + %1 = mul i32 %i.03, %As ; <i32> [#uses=1] + %2 = getelementptr i16* %A, i32 %1 ; <i16*> [#uses=1] + %3 = load i16* %2, align 2 ; <i16> [#uses=1] + %4 = sext i16 %3 to i32 ; <i32> [#uses=1] + %5 = mul i32 %i.03, %Bs ; <i32> [#uses=1] + %6 = getelementptr i16* %B, i32 %5 ; <i16*> [#uses=1] + %7 = load i16* %6, align 2 ; <i16> [#uses=1] + %8 = sext i16 %7 to i32 ; <i32> [#uses=1] + %9 = mul i32 %8, %4 ; <i32> [#uses=1] + %10 = add i32 %9, %sum.04 ; <i32> [#uses=2] + %indvar.next = add i32 %i.03, 1 ; <i32> [#uses=2] + %exitcond = icmp eq i32 %indvar.next, %N ; <i1> [#uses=1] + br i1 %exitcond, label %bb1.bb2_crit_edge, label %bb + +bb1.bb2_crit_edge: ; preds = %bb + %phitmp = trunc i32 %10 to i16 ; <i16> [#uses=1] + br label %bb2 + +bb2: ; preds = %entry, %bb1.bb2_crit_edge + %sum.0.lcssa = phi i16 [ %phitmp, %bb1.bb2_crit_edge ], [ 0, %entry ] ; <i16> [#uses=1] + store i16 %sum.0.lcssa, i16* %C, align 2 + ret void +} diff --git a/test/CodeGen/X86/stack-color-with-reg.ll b/test/CodeGen/X86/stack-color-with-reg.ll index a8ae8e8168..672f77eef0 100644 --- a/test/CodeGen/X86/stack-color-with-reg.ll +++ b/test/CodeGen/X86/stack-color-with-reg.ll @@ -1,6 +1,6 @@ ; RUN: llc < %s -mtriple=x86_64-apple-darwin10 -relocation-model=pic -disable-fp-elim -color-ss-with-regs -stats -info-output-file - > %t -; RUN: grep stackcoloring %t | grep "stack slot refs replaced with reg refs" | grep 8 -; RUN: grep asm-printer %t | grep 182 +; RUN: grep stackcoloring %t | grep "stack slot refs replaced with reg refs" | grep 5 +; RUN: grep asm-printer %t | grep 179 type { [62 x %struct.Bitvec*] } ; type %0 type { i8* } ; type %1 |