[llvm-commits] [llvm] r91598 - in /llvm/trunk: include/llvm/Analysis/IVUsers.h include/llvm/Analysis/LoopInfo.h lib/Analysis/IVUsers.cpp lib/CodeGen/LLVMTargetMachine.cpp lib/Transforms/Scalar/CodeGenPrepare.cpp lib/Transforms/Scalar/LoopStrengthReduce.cpp
Evan Cheng
evan.cheng at apple.com
Thu Dec 17 01:39:49 PST 2009
Author: evancheng
Date: Thu Dec 17 03:39:49 2009
New Revision: 91598
URL: http://llvm.org/viewvc/llvm-project?rev=91598&view=rev
Log:
Revert 91280-91283, 91286-91289, 91291, 91293, 91295-91296. It apparently introduced a non-deterministic behavior in the optimizer somewhere.
Modified:
llvm/trunk/include/llvm/Analysis/IVUsers.h
llvm/trunk/include/llvm/Analysis/LoopInfo.h
llvm/trunk/lib/Analysis/IVUsers.cpp
llvm/trunk/lib/CodeGen/LLVMTargetMachine.cpp
llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp
llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp
Modified: llvm/trunk/include/llvm/Analysis/IVUsers.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/IVUsers.h?rev=91598&r1=91597&r2=91598&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/IVUsers.h (original)
+++ llvm/trunk/include/llvm/Analysis/IVUsers.h Thu Dec 17 03:39:49 2009
@@ -175,11 +175,11 @@
ScalarEvolution *SE;
SmallPtrSet<Instruction*,16> Processed;
+public:
/// IVUses - A list of all tracked IV uses of induction variable expressions
/// we are interested in.
ilist<IVUsersOfOneStride> IVUses;
-public:
/// IVUsesByStride - A mapping from the strides in StrideOrder to the
/// uses in IVUses.
std::map<const SCEV *, IVUsersOfOneStride*> IVUsesByStride;
Modified: llvm/trunk/include/llvm/Analysis/LoopInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Analysis/LoopInfo.h?rev=91598&r1=91597&r2=91598&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Analysis/LoopInfo.h (original)
+++ llvm/trunk/include/llvm/Analysis/LoopInfo.h Thu Dec 17 03:39:49 2009
@@ -976,6 +976,13 @@
void removeBlock(BasicBlock *BB) {
LI.removeBlock(BB);
}
+
+ static bool isNotAlreadyContainedIn(const Loop *SubLoop,
+ const Loop *ParentLoop) {
+ return
+ LoopInfoBase<BasicBlock, Loop>::isNotAlreadyContainedIn(SubLoop,
+ ParentLoop);
+ }
};
Modified: llvm/trunk/lib/Analysis/IVUsers.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Analysis/IVUsers.cpp?rev=91598&r1=91597&r2=91598&view=diff
==============================================================================
--- llvm/trunk/lib/Analysis/IVUsers.cpp (original)
+++ llvm/trunk/lib/Analysis/IVUsers.cpp Thu Dec 17 03:39:49 2009
@@ -53,7 +53,7 @@
if (newLoop == L)
return false;
// if newLoop is an outer loop of L, this is OK.
- if (newLoop->contains(L->getHeader()))
+ if (!LoopInfo::isNotAlreadyContainedIn(L, newLoop))
return false;
}
return true;
@@ -307,7 +307,6 @@
for (BasicBlock::iterator I = L->getHeader()->begin(); isa<PHINode>(I); ++I)
AddUsersIfInteresting(I);
- Processed.clear();
return false;
}
@@ -370,7 +369,7 @@
void IVUsers::releaseMemory() {
IVUsesByStride.clear();
StrideOrder.clear();
- IVUses.clear();
+ Processed.clear();
}
void IVStrideUse::deleted() {
Modified: llvm/trunk/lib/CodeGen/LLVMTargetMachine.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LLVMTargetMachine.cpp?rev=91598&r1=91597&r2=91598&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/LLVMTargetMachine.cpp (original)
+++ llvm/trunk/lib/CodeGen/LLVMTargetMachine.cpp Thu Dec 17 03:39:49 2009
@@ -31,6 +31,10 @@
bool EnableFastISel;
}
+static cl::opt<bool> X1("x1");
+static cl::opt<bool> X2("x2");
+static cl::opt<bool> X3("x3");
+static cl::opt<bool> X4("x4");
static cl::opt<bool> DisablePostRA("disable-post-ra", cl::Hidden,
cl::desc("Disable Post Regalloc"));
static cl::opt<bool> DisableBranchFold("disable-branch-fold", cl::Hidden,
@@ -239,6 +243,11 @@
PM.add(createGVNPass(/*NoPRE=*/false, /*NoLoads=*/true));
}
+ if (X1)
+ PM.add(createPrintFunctionPass("\n\n"
+ "*** Before LSR ***\n",
+ &errs()));
+
// Run loop strength reduction before anything else.
if (OptLevel != CodeGenOpt::None && !DisableLSR) {
PM.add(createLoopStrengthReducePass(getTargetLowering()));
@@ -246,6 +255,11 @@
PM.add(createPrintFunctionPass("\n\n*** Code after LSR ***\n", &errs()));
}
+ if (X2)
+ PM.add(createPrintFunctionPass("\n\n"
+ "*** After LSR ***\n",
+ &errs()));
+
// Turn exception handling constructs into something the code generators can
// handle.
switch (getMCAsmInfo()->getExceptionHandlingType())
@@ -268,9 +282,19 @@
// Make sure that no unreachable blocks are instruction selected.
PM.add(createUnreachableBlockEliminationPass());
+ if (X3)
+ PM.add(createPrintFunctionPass("\n\n"
+ "*** Before CGP ***\n",
+ &errs()));
+
if (OptLevel != CodeGenOpt::None && !DisableCGP)
PM.add(createCodeGenPreparePass(getTargetLowering()));
+ if (X4)
+ PM.add(createPrintFunctionPass("\n\n"
+ "*** After CGP ***\n",
+ &errs()));
+
PM.add(createStackProtectorPass(getTargetLowering()));
if (PrintISelInput)
Modified: llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp?rev=91598&r1=91597&r2=91598&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/CodeGenPrepare.cpp Thu Dec 17 03:39:49 2009
@@ -48,7 +48,7 @@
/// TLI - Keep a pointer of a TargetLowering to consult for determining
/// transformation profitability.
const TargetLowering *TLI;
- ProfileInfo *PI;
+ ProfileInfo *PFI;
/// BackEdges - Keep a set of all the loop back edges.
///
@@ -99,7 +99,7 @@
bool CodeGenPrepare::runOnFunction(Function &F) {
bool EverMadeChange = false;
- PI = getAnalysisIfAvailable<ProfileInfo>();
+ PFI = getAnalysisIfAvailable<ProfileInfo>();
// First pass, eliminate blocks that contain only PHI nodes and an
// unconditional branch.
EverMadeChange |= EliminateMostlyEmptyBlocks(F);
@@ -288,9 +288,9 @@
// The PHIs are now updated, change everything that refers to BB to use
// DestBB and remove BB.
BB->replaceAllUsesWith(DestBB);
- if (PI) {
- PI->replaceAllUses(BB, DestBB);
- PI->removeEdge(ProfileInfo::getEdge(BB, DestBB));
+ if (PFI) {
+ PFI->replaceAllUses(BB, DestBB);
+ PFI->removeEdge(ProfileInfo::getEdge(BB, DestBB));
}
BB->eraseFromParent();
@@ -368,9 +368,9 @@
// If we found a workable predecessor, change TI to branch to Succ.
if (FoundMatch) {
- ProfileInfo *PI = P->getAnalysisIfAvailable<ProfileInfo>();
- if (PI)
- PI->splitEdge(TIBB, Dest, Pred);
+ ProfileInfo *PFI = P->getAnalysisIfAvailable<ProfileInfo>();
+ if (PFI)
+ PFI->splitEdge(TIBB, Dest, Pred);
Dest->removePredecessor(TIBB);
TI->setSuccessor(SuccNum, Pred);
return;
Modified: llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp?rev=91598&r1=91597&r2=91598&view=diff
==============================================================================
--- llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp (original)
+++ llvm/trunk/lib/Transforms/Scalar/LoopStrengthReduce.cpp Thu Dec 17 03:39:49 2009
@@ -24,14 +24,18 @@
#include "llvm/Constants.h"
#include "llvm/Instructions.h"
#include "llvm/IntrinsicInst.h"
+#include "llvm/Type.h"
#include "llvm/DerivedTypes.h"
+#include "llvm/Analysis/Dominators.h"
#include "llvm/Analysis/IVUsers.h"
+#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/LoopPass.h"
#include "llvm/Analysis/ScalarEvolutionExpander.h"
#include "llvm/Transforms/Utils/AddrModeMatcher.h"
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Transforms/Utils/Local.h"
#include "llvm/ADT/Statistic.h"
+#include "llvm/Support/CFG.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/ValueHandle.h"
@@ -81,6 +85,8 @@
class LoopStrengthReduce : public LoopPass {
IVUsers *IU;
+ LoopInfo *LI;
+ DominatorTree *DT;
ScalarEvolution *SE;
bool Changed;
@@ -88,6 +94,10 @@
/// particular stride.
std::map<const SCEV *, IVsOfOneStride> IVsByStride;
+ /// StrideNoReuse - Keep track of all the strides whose ivs cannot be
+ /// reused (nor should they be rewritten to reuse other strides).
+ SmallSet<const SCEV *, 4> StrideNoReuse;
+
/// DeadInsts - Keep track of instructions we may have made dead, so that
/// we can remove them after we are done working.
SmallVector<WeakVH, 16> DeadInsts;
@@ -99,7 +109,8 @@
public:
static char ID; // Pass ID, replacement for typeid
explicit LoopStrengthReduce(const TargetLowering *tli = NULL) :
- LoopPass(&ID), TLI(tli) {}
+ LoopPass(&ID), TLI(tli) {
+ }
bool runOnLoop(Loop *L, LPPassManager &LPM);
@@ -107,11 +118,13 @@
// We split critical edges, so we change the CFG. However, we do update
// many analyses if they are around.
AU.addPreservedID(LoopSimplifyID);
- AU.addPreserved("loops");
- AU.addPreserved("domfrontier");
- AU.addPreserved("domtree");
+ AU.addPreserved<LoopInfo>();
+ AU.addPreserved<DominanceFrontier>();
+ AU.addPreserved<DominatorTree>();
AU.addRequiredID(LoopSimplifyID);
+ AU.addRequired<LoopInfo>();
+ AU.addRequired<DominatorTree>();
AU.addRequired<ScalarEvolution>();
AU.addPreserved<ScalarEvolution>();
AU.addRequired<IVUsers>();
@@ -215,17 +228,19 @@
if (DeadInsts.empty()) return;
while (!DeadInsts.empty()) {
- Instruction *I = dyn_cast_or_null<Instruction>(DeadInsts.pop_back_val());
+ Instruction *I = dyn_cast_or_null<Instruction>(DeadInsts.back());
+ DeadInsts.pop_back();
if (I == 0 || !isInstructionTriviallyDead(I))
continue;
- for (User::op_iterator OI = I->op_begin(), E = I->op_end(); OI != E; ++OI)
+ for (User::op_iterator OI = I->op_begin(), E = I->op_end(); OI != E; ++OI) {
if (Instruction *U = dyn_cast<Instruction>(*OI)) {
*OI = 0;
if (U->use_empty())
DeadInsts.push_back(U);
}
+ }
I->eraseFromParent();
Changed = true;
@@ -285,6 +300,9 @@
/// BasedUser - For a particular base value, keep information about how we've
/// partitioned the expression so far.
struct BasedUser {
+ /// SE - The current ScalarEvolution object.
+ ScalarEvolution *SE;
+
/// Base - The Base value for the PHI node that needs to be inserted for
/// this use. As the use is processed, information gets moved from this
/// field to the Imm field (below). BasedUser values are sorted by this
@@ -316,9 +334,9 @@
bool isUseOfPostIncrementedValue;
BasedUser(IVStrideUse &IVSU, ScalarEvolution *se)
- : Base(IVSU.getOffset()), Inst(IVSU.getUser()),
+ : SE(se), Base(IVSU.getOffset()), Inst(IVSU.getUser()),
OperandValToReplace(IVSU.getOperandValToReplace()),
- Imm(se->getIntegerSCEV(0, Base->getType())),
+ Imm(SE->getIntegerSCEV(0, Base->getType())),
isUseOfPostIncrementedValue(IVSU.isUseOfPostIncrementedValue()) {}
// Once we rewrite the code to insert the new IVs we want, update the
@@ -327,14 +345,14 @@
void RewriteInstructionToUseNewBase(const SCEV *const &NewBase,
Instruction *InsertPt,
SCEVExpander &Rewriter, Loop *L, Pass *P,
- SmallVectorImpl<WeakVH> &DeadInsts,
- ScalarEvolution *SE);
+ LoopInfo &LI,
+ SmallVectorImpl<WeakVH> &DeadInsts);
Value *InsertCodeForBaseAtPosition(const SCEV *const &NewBase,
const Type *Ty,
SCEVExpander &Rewriter,
- Instruction *IP,
- ScalarEvolution *SE);
+ Instruction *IP, Loop *L,
+ LoopInfo &LI);
void dump() const;
};
}
@@ -348,12 +366,27 @@
Value *BasedUser::InsertCodeForBaseAtPosition(const SCEV *const &NewBase,
const Type *Ty,
SCEVExpander &Rewriter,
- Instruction *IP,
- ScalarEvolution *SE) {
- Value *Base = Rewriter.expandCodeFor(NewBase, 0, IP);
+ Instruction *IP, Loop *L,
+ LoopInfo &LI) {
+ // Figure out where we *really* want to insert this code. In particular, if
+ // the user is inside of a loop that is nested inside of L, we really don't
+ // want to insert this expression before the user, we'd rather pull it out as
+ // many loops as possible.
+ Instruction *BaseInsertPt = IP;
+
+ // Figure out the most-nested loop that IP is in.
+ Loop *InsertLoop = LI.getLoopFor(IP->getParent());
+
+ // If InsertLoop is not L, and InsertLoop is nested inside of L, figure out
+ // the preheader of the outer-most loop where NewBase is not loop invariant.
+ if (L->contains(IP->getParent()))
+ while (InsertLoop && NewBase->isLoopInvariant(InsertLoop)) {
+ BaseInsertPt = InsertLoop->getLoopPreheader()->getTerminator();
+ InsertLoop = InsertLoop->getParentLoop();
+ }
+
+ Value *Base = Rewriter.expandCodeFor(NewBase, 0, BaseInsertPt);
- // Wrap the base in a SCEVUnknown so that ScalarEvolution doesn't try to
- // re-analyze it.
const SCEV *NewValSCEV = SE->getUnknown(Base);
// Always emit the immediate into the same block as the user.
@@ -372,8 +405,8 @@
void BasedUser::RewriteInstructionToUseNewBase(const SCEV *const &NewBase,
Instruction *NewBasePt,
SCEVExpander &Rewriter, Loop *L, Pass *P,
- SmallVectorImpl<WeakVH> &DeadInsts,
- ScalarEvolution *SE) {
+ LoopInfo &LI,
+ SmallVectorImpl<WeakVH> &DeadInsts) {
if (!isa<PHINode>(Inst)) {
// By default, insert code at the user instruction.
BasicBlock::iterator InsertPt = Inst;
@@ -402,7 +435,7 @@
}
Value *NewVal = InsertCodeForBaseAtPosition(NewBase,
OperandValToReplace->getType(),
- Rewriter, InsertPt, SE);
+ Rewriter, InsertPt, L, LI);
// Replace the use of the operand Value with the new Phi we just created.
Inst->replaceUsesOfWith(OperandValToReplace, NewVal);
@@ -464,7 +497,7 @@
PHIPred->getTerminator() :
OldLoc->getParent()->getTerminator();
Code = InsertCodeForBaseAtPosition(NewBase, PN->getType(),
- Rewriter, InsertPt, SE);
+ Rewriter, InsertPt, L, LI);
DEBUG(errs() << " Changing PHI use to ");
DEBUG(WriteAsOperand(errs(), Code, /*PrintType=*/false));
@@ -940,13 +973,17 @@
const SCEV *const &Stride,
IVExpr &IV, const Type *Ty,
const std::vector<BasedUser>& UsersToProcess) {
+ if (StrideNoReuse.count(Stride))
+ return SE->getIntegerSCEV(0, Stride->getType());
+
if (const SCEVConstant *SC = dyn_cast<SCEVConstant>(Stride)) {
int64_t SInt = SC->getValue()->getSExtValue();
for (unsigned NewStride = 0, e = IU->StrideOrder.size();
NewStride != e; ++NewStride) {
std::map<const SCEV *, IVsOfOneStride>::iterator SI =
IVsByStride.find(IU->StrideOrder[NewStride]);
- if (SI == IVsByStride.end() || !isa<SCEVConstant>(SI->first))
+ if (SI == IVsByStride.end() || !isa<SCEVConstant>(SI->first) ||
+ StrideNoReuse.count(SI->first))
continue;
// The other stride has no uses, don't reuse it.
std::map<const SCEV *, IVUsersOfOneStride *>::iterator UI =
@@ -1705,8 +1742,8 @@
RewriteExpr = SE->getAddExpr(RewriteExpr, SE->getUnknown(BaseV));
User.RewriteInstructionToUseNewBase(RewriteExpr, NewBasePt,
- Rewriter, L, this,
- DeadInsts, SE);
+ Rewriter, L, this, *LI,
+ DeadInsts);
// Mark old value we replaced as possibly dead, so that it is eliminated
// if we just replaced the last use of that value.
@@ -2670,6 +2707,8 @@
bool LoopStrengthReduce::runOnLoop(Loop *L, LPPassManager &LPM) {
IU = &getAnalysis<IVUsers>();
+ LI = &getAnalysis<LoopInfo>();
+ DT = &getAnalysis<DominatorTree>();
SE = &getAnalysis<ScalarEvolution>();
Changed = false;
@@ -2715,15 +2754,16 @@
// After all sharing is done, see if we can adjust the loop to test against
// zero instead of counting up to a maximum. This is usually faster.
OptimizeLoopCountIV(L);
-
- // We're done analyzing this loop; release all the state we built up for it.
- IVsByStride.clear();
-
- // Clean up after ourselves
- if (!DeadInsts.empty())
- DeleteTriviallyDeadInstructions();
}
+ // We're done analyzing this loop; release all the state we built up for it.
+ IVsByStride.clear();
+ StrideNoReuse.clear();
+
+ // Clean up after ourselves
+ if (!DeadInsts.empty())
+ DeleteTriviallyDeadInstructions();
+
// At this point, it is worth checking to see if any recurrence PHIs are also
// dead, so that we can remove them as well.
DeleteDeadPHIs(L->getHeader());
More information about the llvm-commits
mailing list