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Wind SCEV back in time, to Nov 18th. This 'fixes' PR3275, PR3294, PR3295,
PR3296 and PR3302. git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@62160 91177308-0d34-0410-b5e6-96231b3b80d8
This commit is contained in:
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@ -225,7 +225,6 @@ namespace llvm {
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return getMulExpr(Ops);
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}
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SCEVHandle getUDivExpr(const SCEVHandle &LHS, const SCEVHandle &RHS);
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SCEVHandle getSDivExpr(const SCEVHandle &LHS, const SCEVHandle &RHS);
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SCEVHandle getAddRecExpr(const SCEVHandle &Start, const SCEVHandle &Step,
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const Loop *L);
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SCEVHandle getAddRecExpr(std::vector<SCEVHandle> &Operands,
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@ -14,7 +14,7 @@
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#ifndef LLVM_ANALYSIS_SCALAREVOLUTION_EXPANDER_H
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#define LLVM_ANALYSIS_SCALAREVOLUTION_EXPANDER_H
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#include "llvm/Instruction.h"
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#include "llvm/Instructions.h"
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#include "llvm/Type.h"
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#include "llvm/Analysis/ScalarEvolution.h"
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#include "llvm/Analysis/ScalarEvolutionExpressions.h"
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@ -104,8 +104,6 @@ namespace llvm {
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Value *visitUDivExpr(SCEVUDivExpr *S);
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Value *visitSDivExpr(SCEVSDivExpr *S);
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Value *visitAddRecExpr(SCEVAddRecExpr *S);
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Value *visitSMaxExpr(SCEVSMaxExpr *S);
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@ -119,3 +117,4 @@ namespace llvm {
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}
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#endif
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@ -25,7 +25,7 @@ namespace llvm {
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// These should be ordered in terms of increasing complexity to make the
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// folders simpler.
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scConstant, scTruncate, scZeroExtend, scSignExtend, scAddExpr, scMulExpr,
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scUDivExpr, scSDivExpr, scAddRecExpr, scUMaxExpr, scSMaxExpr, scUnknown,
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scUDivExpr, scAddRecExpr, scUMaxExpr, scSMaxExpr, scUnknown,
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scCouldNotCompute
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};
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@ -357,55 +357,6 @@ namespace llvm {
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};
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//===--------------------------------------------------------------------===//
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/// SCEVSDivExpr - This class represents a binary signed division operation.
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///
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class SCEVSDivExpr : public SCEV {
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friend class ScalarEvolution;
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SCEVHandle LHS, RHS;
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SCEVSDivExpr(const SCEVHandle &lhs, const SCEVHandle &rhs)
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: SCEV(scSDivExpr), LHS(lhs), RHS(rhs) {}
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virtual ~SCEVSDivExpr();
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public:
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const SCEVHandle &getLHS() const { return LHS; }
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const SCEVHandle &getRHS() const { return RHS; }
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virtual bool isLoopInvariant(const Loop *L) const {
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return LHS->isLoopInvariant(L) && RHS->isLoopInvariant(L);
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}
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virtual bool hasComputableLoopEvolution(const Loop *L) const {
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return LHS->hasComputableLoopEvolution(L) &&
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RHS->hasComputableLoopEvolution(L);
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}
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SCEVHandle replaceSymbolicValuesWithConcrete(const SCEVHandle &Sym,
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const SCEVHandle &Conc,
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ScalarEvolution &SE) const {
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SCEVHandle L = LHS->replaceSymbolicValuesWithConcrete(Sym, Conc, SE);
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SCEVHandle R = RHS->replaceSymbolicValuesWithConcrete(Sym, Conc, SE);
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if (L == LHS && R == RHS)
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return this;
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else
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return SE.getSDivExpr(L, R);
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}
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virtual const Type *getType() const;
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void print(std::ostream &OS) const;
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void print(std::ostream *OS) const { if (OS) print(*OS); }
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/// Methods for support type inquiry through isa, cast, and dyn_cast:
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static inline bool classof(const SCEVSDivExpr *S) { return true; }
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static inline bool classof(const SCEV *S) {
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return S->getSCEVType() == scSDivExpr;
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}
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};
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//===--------------------------------------------------------------------===//
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/// SCEVAddRecExpr - This node represents a polynomial recurrence on the trip
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/// count of the specified loop.
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@ -599,8 +550,6 @@ namespace llvm {
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return ((SC*)this)->visitMulExpr((SCEVMulExpr*)S);
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case scUDivExpr:
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return ((SC*)this)->visitUDivExpr((SCEVUDivExpr*)S);
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case scSDivExpr:
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return ((SC*)this)->visitSDivExpr((SCEVSDivExpr*)S);
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case scAddRecExpr:
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return ((SC*)this)->visitAddRecExpr((SCEVAddRecExpr*)S);
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case scSMaxExpr:
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@ -112,7 +112,6 @@ char ScalarEvolution::ID = 0;
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SCEV::~SCEV() {}
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void SCEV::dump() const {
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print(cerr);
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cerr << '\n';
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}
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uint32_t SCEV::getBitWidth() const {
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@ -325,26 +324,6 @@ const Type *SCEVUDivExpr::getType() const {
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return LHS->getType();
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}
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// SCEVSDivs - Only allow the creation of one SCEVSDivExpr for any particular
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// input. Don't use a SCEVHandle here, or else the object will never be
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// deleted!
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static ManagedStatic<std::map<std::pair<SCEV*, SCEV*>,
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SCEVSDivExpr*> > SCEVSDivs;
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SCEVSDivExpr::~SCEVSDivExpr() {
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SCEVSDivs->erase(std::make_pair(LHS, RHS));
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}
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void SCEVSDivExpr::print(std::ostream &OS) const {
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OS << "(" << *LHS << " /s " << *RHS << ")";
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}
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const Type *SCEVSDivExpr::getType() const {
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return LHS->getType();
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}
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// SCEVAddRecExprs - Only allow the creation of one SCEVAddRecExpr for any
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// particular input. Don't use a SCEVHandle here, or else the object will never
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// be deleted!
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@ -1130,12 +1109,9 @@ SCEVHandle ScalarEvolution::getMulExpr(std::vector<SCEVHandle> &Ops) {
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}
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SCEVHandle ScalarEvolution::getUDivExpr(const SCEVHandle &LHS, const SCEVHandle &RHS) {
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if (LHS == RHS)
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return getIntegerSCEV(1, LHS->getType()); // X udiv X --> 1
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if (SCEVConstant *RHSC = dyn_cast<SCEVConstant>(RHS)) {
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if (RHSC->getValue()->equalsInt(1))
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return LHS; // X udiv 1 --> X
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return LHS; // X udiv 1 --> x
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if (SCEVConstant *LHSC = dyn_cast<SCEVConstant>(LHS)) {
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Constant *LHSCV = LHSC->getValue();
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@ -1144,34 +1120,13 @@ SCEVHandle ScalarEvolution::getUDivExpr(const SCEVHandle &LHS, const SCEVHandle
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}
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}
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// FIXME: implement folding of (X*4)/4 when we know X*4 doesn't overflow.
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SCEVUDivExpr *&Result = (*SCEVUDivs)[std::make_pair(LHS, RHS)];
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if (Result == 0) Result = new SCEVUDivExpr(LHS, RHS);
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return Result;
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}
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SCEVHandle ScalarEvolution::getSDivExpr(const SCEVHandle &LHS, const SCEVHandle &RHS) {
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if (LHS == RHS)
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return getIntegerSCEV(1, LHS->getType()); // X sdiv X --> 1
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if (SCEVConstant *RHSC = dyn_cast<SCEVConstant>(RHS)) {
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if (RHSC->getValue()->equalsInt(1))
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return LHS; // X sdiv 1 --> X
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if (RHSC->getValue()->isAllOnesValue())
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return getNegativeSCEV(LHS); // X sdiv -1 --> -X
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if (SCEVConstant *LHSC = dyn_cast<SCEVConstant>(LHS)) {
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Constant *LHSCV = LHSC->getValue();
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Constant *RHSCV = RHSC->getValue();
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return getUnknown(ConstantExpr::getSDiv(LHSCV, RHSCV));
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}
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}
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SCEVSDivExpr *&Result = (*SCEVSDivs)[std::make_pair(LHS, RHS)];
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if (Result == 0) Result = new SCEVSDivExpr(LHS, RHS);
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return Result;
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}
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/// SCEVAddRecExpr::get - Get a add recurrence expression for the
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/// specified loop. Simplify the expression as much as possible.
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@ -1522,7 +1477,7 @@ namespace {
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/// specified less-than comparison will execute. If not computable, return
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/// UnknownValue. isSigned specifies whether the less-than is signed.
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SCEVHandle HowManyLessThans(SCEV *LHS, SCEV *RHS, const Loop *L,
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bool isSigned, bool trueWhenEqual);
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bool isSigned);
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/// getPredecessorWithUniqueSuccessorForBB - Return a predecessor of BB
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/// (which may not be an immediate predecessor) which has exactly one
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@ -1532,13 +1487,7 @@ namespace {
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/// executesAtLeastOnce - Test whether entry to the loop is protected by
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/// a conditional between LHS and RHS.
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bool executesAtLeastOnce(const Loop *L, bool isSigned, bool trueWhenEqual,
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SCEV *LHS, SCEV *RHS);
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/// potentialInfiniteLoop - Test whether the loop might jump over the exit value
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/// due to wrapping.
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bool potentialInfiniteLoop(SCEV *Stride, SCEV *RHS, bool isSigned,
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bool trueWhenEqual);
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bool executesAtLeastOnce(const Loop *L, bool isSigned, SCEV *LHS, SCEV *RHS);
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/// getConstantEvolutionLoopExitValue - If we know that the specified Phi is
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/// in the header of its containing loop, we know the loop executes a
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@ -1777,7 +1726,7 @@ static uint32_t GetMinTrailingZeros(SCEVHandle S) {
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return MinOpRes;
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}
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// SCEVUDivExpr, SCEVSDivExpr, SCEVUnknown
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// SCEVUDivExpr, SCEVUnknown
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return 0;
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}
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@ -1807,9 +1756,6 @@ SCEVHandle ScalarEvolutionsImpl::createSCEV(Value *V) {
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case Instruction::UDiv:
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return SE.getUDivExpr(getSCEV(U->getOperand(0)),
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getSCEV(U->getOperand(1)));
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case Instruction::SDiv:
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return SE.getSDivExpr(getSCEV(U->getOperand(0)),
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getSCEV(U->getOperand(1)));
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case Instruction::Sub:
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return SE.getMinusSCEV(getSCEV(U->getOperand(0)),
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getSCEV(U->getOperand(1)));
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@ -1853,7 +1799,7 @@ SCEVHandle ScalarEvolutionsImpl::createSCEV(Value *V) {
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break;
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case Instruction::LShr:
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// Turn logical shift right of a constant into an unsigned divide.
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// Turn logical shift right of a constant into a unsigned divide.
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if (ConstantInt *SA = dyn_cast<ConstantInt>(U->getOperand(1))) {
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uint32_t BitWidth = cast<IntegerType>(V->getType())->getBitWidth();
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Constant *X = ConstantInt::get(
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@ -2079,46 +2025,24 @@ SCEVHandle ScalarEvolutionsImpl::ComputeIterationCount(const Loop *L) {
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break;
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}
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case ICmpInst::ICMP_SLT: {
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SCEVHandle TC = HowManyLessThans(LHS, RHS, L, true, false);
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SCEVHandle TC = HowManyLessThans(LHS, RHS, L, true);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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case ICmpInst::ICMP_SGT: {
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SCEVHandle TC = HowManyLessThans(SE.getNotSCEV(LHS),
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SE.getNotSCEV(RHS), L, true, false);
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SE.getNotSCEV(RHS), L, true);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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case ICmpInst::ICMP_ULT: {
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SCEVHandle TC = HowManyLessThans(LHS, RHS, L, false, false);
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SCEVHandle TC = HowManyLessThans(LHS, RHS, L, false);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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case ICmpInst::ICMP_UGT: {
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SCEVHandle TC = HowManyLessThans(SE.getNotSCEV(LHS),
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SE.getNotSCEV(RHS), L, false, false);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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case ICmpInst::ICMP_SLE: {
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SCEVHandle TC = HowManyLessThans(LHS, RHS, L, true, true);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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case ICmpInst::ICMP_SGE: {
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SCEVHandle TC = HowManyLessThans(SE.getNotSCEV(LHS),
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SE.getNotSCEV(RHS), L, true, true);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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case ICmpInst::ICMP_ULE: {
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SCEVHandle TC = HowManyLessThans(LHS, RHS, L, false, true);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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case ICmpInst::ICMP_UGE: {
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SCEVHandle TC = HowManyLessThans(SE.getNotSCEV(LHS),
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SE.getNotSCEV(RHS), L, false, true);
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SE.getNotSCEV(RHS), L, false);
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if (!isa<SCEVCouldNotCompute>(TC)) return TC;
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break;
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}
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@ -2553,26 +2477,16 @@ SCEVHandle ScalarEvolutionsImpl::getSCEVAtScope(SCEV *V, const Loop *L) {
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return Comm;
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}
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if (SCEVUDivExpr *UDiv = dyn_cast<SCEVUDivExpr>(V)) {
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SCEVHandle LHS = getSCEVAtScope(UDiv->getLHS(), L);
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if (SCEVUDivExpr *Div = dyn_cast<SCEVUDivExpr>(V)) {
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SCEVHandle LHS = getSCEVAtScope(Div->getLHS(), L);
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if (LHS == UnknownValue) return LHS;
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SCEVHandle RHS = getSCEVAtScope(UDiv->getRHS(), L);
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SCEVHandle RHS = getSCEVAtScope(Div->getRHS(), L);
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if (RHS == UnknownValue) return RHS;
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if (LHS == UDiv->getLHS() && RHS == UDiv->getRHS())
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return UDiv; // must be loop invariant
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if (LHS == Div->getLHS() && RHS == Div->getRHS())
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return Div; // must be loop invariant
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return SE.getUDivExpr(LHS, RHS);
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}
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if (SCEVSDivExpr *SDiv = dyn_cast<SCEVSDivExpr>(V)) {
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SCEVHandle LHS = getSCEVAtScope(SDiv->getLHS(), L);
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if (LHS == UnknownValue) return LHS;
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SCEVHandle RHS = getSCEVAtScope(SDiv->getRHS(), L);
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if (RHS == UnknownValue) return RHS;
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if (LHS == SDiv->getLHS() && RHS == SDiv->getRHS())
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return SDiv; // must be loop invariant
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return SE.getSDivExpr(LHS, RHS);
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}
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// If this is a loop recurrence for a loop that does not contain L, then we
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// are dealing with the final value computed by the loop.
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if (SCEVAddRecExpr *AddRec = dyn_cast<SCEVAddRecExpr>(V)) {
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@ -2824,7 +2738,6 @@ ScalarEvolutionsImpl::getPredecessorWithUniqueSuccessorForBB(BasicBlock *BB) {
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/// executesAtLeastOnce - Test whether entry to the loop is protected by
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/// a conditional between LHS and RHS.
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bool ScalarEvolutionsImpl::executesAtLeastOnce(const Loop *L, bool isSigned,
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bool trueWhenEqual,
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SCEV *LHS, SCEV *RHS) {
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BasicBlock *Preheader = L->getLoopPreheader();
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BasicBlock *PreheaderDest = L->getHeader();
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@ -2857,36 +2770,20 @@ bool ScalarEvolutionsImpl::executesAtLeastOnce(const Loop *L, bool isSigned,
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switch (Cond) {
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case ICmpInst::ICMP_UGT:
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if (isSigned || trueWhenEqual) continue;
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if (isSigned) continue;
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std::swap(PreCondLHS, PreCondRHS);
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Cond = ICmpInst::ICMP_ULT;
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break;
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case ICmpInst::ICMP_SGT:
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if (!isSigned || trueWhenEqual) continue;
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if (!isSigned) continue;
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std::swap(PreCondLHS, PreCondRHS);
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Cond = ICmpInst::ICMP_SLT;
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break;
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case ICmpInst::ICMP_ULT:
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if (isSigned || trueWhenEqual) continue;
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if (isSigned) continue;
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break;
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case ICmpInst::ICMP_SLT:
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if (!isSigned || trueWhenEqual) continue;
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break;
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case ICmpInst::ICMP_UGE:
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if (isSigned || !trueWhenEqual) continue;
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std::swap(PreCondLHS, PreCondRHS);
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Cond = ICmpInst::ICMP_ULE;
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break;
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case ICmpInst::ICMP_SGE:
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if (!isSigned || !trueWhenEqual) continue;
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std::swap(PreCondLHS, PreCondRHS);
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Cond = ICmpInst::ICMP_SLE;
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break;
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case ICmpInst::ICMP_ULE:
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if (isSigned || !trueWhenEqual) continue;
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break;
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case ICmpInst::ICMP_SLE:
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if (!isSigned || !trueWhenEqual) continue;
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if (!isSigned) continue;
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break;
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default:
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continue;
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@ -2905,47 +2802,11 @@ bool ScalarEvolutionsImpl::executesAtLeastOnce(const Loop *L, bool isSigned,
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return false;
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}
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/// potentialInfiniteLoop - Test whether the loop might jump over the exit value
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/// due to wrapping around 2^n.
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bool ScalarEvolutionsImpl::potentialInfiniteLoop(SCEV *Stride, SCEV *RHS,
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bool isSigned, bool trueWhenEqual) {
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// Return true when the distance from RHS to maxint > Stride.
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SCEVConstant *SC = dyn_cast<SCEVConstant>(Stride);
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if (!SC)
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return true;
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if (SC->getValue()->isZero())
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return true;
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if (!trueWhenEqual && SC->getValue()->isOne())
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return false;
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SCEVConstant *R = dyn_cast<SCEVConstant>(RHS);
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if (!R)
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return true;
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// If negative, it wraps around every iteration, but we don't care about that.
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APInt S = SC->getValue()->getValue().abs();
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uint32_t Width = R->getValue()->getBitWidth();
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APInt Dist = (isSigned ? APInt::getSignedMaxValue(Width)
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: APInt::getMaxValue(Width))
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- R->getValue()->getValue();
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// Because we're looking at distance, we perform an unsigned comparison,
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// regardless of the sign of the computation.
|
||||
if (trueWhenEqual)
|
||||
return !S.ult(Dist);
|
||||
else
|
||||
return !S.ule(Dist);
|
||||
}
|
||||
|
||||
/// HowManyLessThans - Return the number of times a backedge containing the
|
||||
/// specified less-than comparison will execute. If not computable, return
|
||||
/// UnknownValue.
|
||||
SCEVHandle ScalarEvolutionsImpl::
|
||||
HowManyLessThans(SCEV *LHS, SCEV *RHS, const Loop *L,
|
||||
bool isSigned, bool trueWhenEqual) {
|
||||
HowManyLessThans(SCEV *LHS, SCEV *RHS, const Loop *L, bool isSigned) {
|
||||
// Only handle: "ADDREC < LoopInvariant".
|
||||
if (!RHS->isLoopInvariant(L)) return UnknownValue;
|
||||
|
||||
@ -2954,56 +2815,34 @@ HowManyLessThans(SCEV *LHS, SCEV *RHS, const Loop *L,
|
||||
return UnknownValue;
|
||||
|
||||
if (AddRec->isAffine()) {
|
||||
SCEVHandle Stride = AddRec->getOperand(1);
|
||||
if (potentialInfiniteLoop(Stride, RHS, isSigned, trueWhenEqual))
|
||||
// FORNOW: We only support unit strides.
|
||||
SCEVHandle One = SE.getIntegerSCEV(1, RHS->getType());
|
||||
if (AddRec->getOperand(1) != One)
|
||||
return UnknownValue;
|
||||
|
||||
// We don't handle this correctly at the moment. The problem is that when
|
||||
// the stride is negative, we're not counting how many times 'less-than' is
|
||||
// true as we approach it, we're counting how far away we are from wrapping
|
||||
// around the backside.
|
||||
if (isSigned &&
|
||||
cast<SCEVConstant>(Stride)->getValue()->getValue().isNegative())
|
||||
return UnknownValue;
|
||||
|
||||
// We know the LHS is of the form {n,+,s} and the RHS is some loop-invariant
|
||||
// m. So, we count the number of iterations in which {n,+,s} < m is true.
|
||||
// Note that we cannot simply return max(m-n,0)/s because it's not safe to
|
||||
// We know the LHS is of the form {n,+,1} and the RHS is some loop-invariant
|
||||
// m. So, we count the number of iterations in which {n,+,1} < m is true.
|
||||
// Note that we cannot simply return max(m-n,0) because it's not safe to
|
||||
// treat m-n as signed nor unsigned due to overflow possibility.
|
||||
//
|
||||
// Assuming that the loop will run at least once, we know that it will
|
||||
// run (m-n)/s times.
|
||||
|
||||
// First, we get the value of the LHS in the first iteration: n
|
||||
SCEVHandle Start = AddRec->getOperand(0);
|
||||
|
||||
SCEVHandle One = SE.getIntegerSCEV(1, RHS->getType());
|
||||
if (executesAtLeastOnce(L, isSigned,
|
||||
SE.getMinusSCEV(AddRec->getOperand(0), One), RHS)) {
|
||||
// Since we know that the condition is true in order to enter the loop,
|
||||
// we know that it will run exactly m-n times.
|
||||
return SE.getMinusSCEV(RHS, Start);
|
||||
} else {
|
||||
// Then, we get the value of the LHS in the first iteration in which the
|
||||
// above condition doesn't hold. This equals to max(m,n).
|
||||
SCEVHandle End = isSigned ? SE.getSMaxExpr(RHS, Start)
|
||||
: SE.getUMaxExpr(RHS, Start);
|
||||
|
||||
// If the expression is less-than-or-equal to, we need to extend the
|
||||
// loop by one iteration.
|
||||
//
|
||||
// The loop won't actually run (m-n)/s times because the loop iterations
|
||||
// might not divide cleanly. For example, if you have {2,+,5} u< 10 the
|
||||
// division would equal one, but the loop runs twice putting the
|
||||
// induction variable at 12.
|
||||
SCEVHandle End = SE.getAddExpr(RHS, Stride);
|
||||
if (!trueWhenEqual)
|
||||
End = SE.getMinusSCEV(End, One);
|
||||
|
||||
if (!executesAtLeastOnce(L, isSigned, trueWhenEqual,
|
||||
SE.getMinusSCEV(Start, One), RHS)) {
|
||||
// If not, we get the value of the LHS in the first iteration in which
|
||||
// the above condition doesn't hold. This equals to max(m,n).
|
||||
End = isSigned ? SE.getSMaxExpr(End, Start)
|
||||
: SE.getUMaxExpr(End, Start);
|
||||
// Finally, we subtract these two values to get the number of times the
|
||||
// backedge is executed: max(m,n)-n.
|
||||
return SE.getMinusSCEV(End, Start);
|
||||
}
|
||||
|
||||
// Finally, we subtract these two values to get the number of times the
|
||||
// backedge is executed: (max(m,n)-n)/s.
|
||||
//
|
||||
// Note that a trip count is always positive. Using SDiv here produces
|
||||
// wrong answers when Start < End.
|
||||
return SE.getUDivExpr(SE.getMinusSCEV(End, Start), Stride);
|
||||
}
|
||||
|
||||
return UnknownValue;
|
||||
|
@ -143,15 +143,6 @@ Value *SCEVExpander::visitUDivExpr(SCEVUDivExpr *S) {
|
||||
return InsertBinop(Instruction::UDiv, LHS, RHS, InsertPt);
|
||||
}
|
||||
|
||||
Value *SCEVExpander::visitSDivExpr(SCEVSDivExpr *S) {
|
||||
// Do not fold sdiv into ashr, unless you know that LHS is positive. On
|
||||
// negative values, it rounds the wrong way.
|
||||
|
||||
Value *LHS = expand(S->getLHS());
|
||||
Value *RHS = expand(S->getRHS());
|
||||
return InsertBinop(Instruction::SDiv, LHS, RHS, InsertPt);
|
||||
}
|
||||
|
||||
Value *SCEVExpander::visitAddRecExpr(SCEVAddRecExpr *S) {
|
||||
const Type *Ty = S->getType();
|
||||
const Loop *L = S->getLoop();
|
||||
|
@ -1,5 +1,6 @@
|
||||
; RUN: llvm-as < %s | opt -analyze -scalar-evolution |& \
|
||||
; RUN: grep {Loop bb: (7 + (-1 \\* %argc)) iterations!}
|
||||
; XFAIL: *
|
||||
|
||||
define i32 @main(i32 %argc, i8** %argv) nounwind {
|
||||
entry:
|
||||
|
@ -1,4 +1,5 @@
|
||||
; RUN: llvm-as < %s | opt -analyze -scalar-evolution |& grep {/u 3}
|
||||
; XFAIL: *
|
||||
|
||||
define i32 @f(i32 %x) nounwind readnone {
|
||||
entry:
|
||||
|
@ -1,4 +1,5 @@
|
||||
; RUN: llvm-as < %s | opt -analyze -scalar-evolution |& grep {/u 3}
|
||||
; XFAIL: *
|
||||
|
||||
define i32 @f(i32 %x) nounwind readnone {
|
||||
entry:
|
||||
|
@ -1,4 +1,5 @@
|
||||
; RUN: llvm-as < %s | opt -analyze -scalar-evolution | grep {255 iterations}
|
||||
; XFAIL: *
|
||||
|
||||
define i32 @foo(i32 %x, i32 %y, i32* %lam, i32* %alp) nounwind {
|
||||
bb1.thread:
|
||||
|
@ -1,4 +1,5 @@
|
||||
; RUN: llvm-as < %s | opt -analyze -scalar-evolution | grep {0 smax}
|
||||
; XFAIL: *
|
||||
|
||||
define i32 @f(i32 %c.idx.val) {
|
||||
|
||||
|
@ -1,5 +1,6 @@
|
||||
; RUN: llvm-as < %s | opt -analyze -scalar-evolution |& \
|
||||
; RUN: grep {(((-1 \\* %i0) + (100005 smax %i0)) /u 5)}
|
||||
; XFAIL: *
|
||||
|
||||
define i32 @foo0(i32 %i0) nounwind {
|
||||
entry:
|
||||
|
@ -1,4 +1,5 @@
|
||||
; RUN: llvm-as < %s | opt -analyze -scalar-evolution |& grep {/u 5}
|
||||
; XFAIL: *
|
||||
|
||||
define i8 @foo0(i8 %i0) nounwind {
|
||||
entry:
|
||||
|
Loading…
Reference in New Issue
Block a user