diff options
Diffstat (limited to 'llvm/lib')
| -rw-r--r-- | llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp | 39 |
1 files changed, 20 insertions, 19 deletions
diff --git a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp index d5c4600b8e1..a5611ff1131 100644 --- a/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp +++ b/llvm/lib/Transforms/Scalar/LoopStrengthReduce.cpp @@ -1066,10 +1066,10 @@ static bool isNonConstantNegative(const SCEV *Expr) { /// progressively move information from the Base field to the Imm field, until /// we eventually have the full access expression to rewrite the use. const SCEV *LoopStrengthReduce::CollectIVUsers(const SCEV *Stride, - IVUsersOfOneStride &Uses, - Loop *L, - bool &AllUsesAreAddresses, - bool &AllUsesAreOutsideLoop, + IVUsersOfOneStride &Uses, + Loop *L, + bool &AllUsesAreAddresses, + bool &AllUsesAreOutsideLoop, std::vector<BasedUser> &UsersToProcess) { // FIXME: Generalize to non-affine IV's. if (!Stride->isLoopInvariant(L)) @@ -1460,10 +1460,10 @@ LoopStrengthReduce::StrengthReduceIVUsersOfStride(const SCEV *Stride, bool AllUsesAreOutsideLoop = true; // Transform our list of users and offsets to a bit more complex table. In - // this new vector, each 'BasedUser' contains 'Base' the base of the - // strided accessas well as the old information from Uses. We progressively - // move information from the Base field to the Imm field, until we eventually - // have the full access expression to rewrite the use. + // this new vector, each 'BasedUser' contains 'Base' the base of the strided + // access as well as the old information from Uses. We progressively move + // information from the Base field to the Imm field until we eventually have + // the full access expression to rewrite the use. std::vector<BasedUser> UsersToProcess; const SCEV *CommonExprs = CollectIVUsers(Stride, Uses, L, AllUsesAreAddresses, AllUsesAreOutsideLoop, @@ -1521,7 +1521,7 @@ LoopStrengthReduce::StrengthReduceIVUsersOfStride(const SCEV *Stride, // DEBUG(dbgs() << "LSR: Examining IVs of TYPE " << *ReplacedTy << " of STRIDE " << *Stride << ":\n" - << " Common base: " << *CommonExprs << "\n"); + << " Common base: " << *CommonExprs << '\n'); SCEVExpander Rewriter(*SE); SCEVExpander PreheaderRewriter(*SE); @@ -1808,14 +1808,14 @@ namespace { /// /// loop: /// ... -/// v1 = v1 + 3 -/// v2 = v2 + 1 -/// if (v2 < 10) goto loop +/// v1 = v1 + 3 +/// v2 = v2 + 1 +/// if (v2 < 10) goto loop /// => /// loop: /// ... -/// v1 = v1 + 3 -/// if (v1 < 30) goto loop +/// v1 = v1 + 3 +/// if (v1 < 30) goto loop ICmpInst *LoopStrengthReduce::ChangeCompareStride(Loop *L, ICmpInst *Cond, IVStrideUse* &CondUse, const SCEV* &CondStride, @@ -1823,13 +1823,14 @@ ICmpInst *LoopStrengthReduce::ChangeCompareStride(Loop *L, ICmpInst *Cond, // If there's only one stride in the loop, there's nothing to do here. if (IU->StrideOrder.size() < 2) return Cond; - // If there are other users of the condition's stride, don't bother - // trying to change the condition because the stride will still - // remain. + + // If there are other users of the condition's stride, don't bother trying to + // change the condition because the stride will still remain. std::map<const SCEV *, IVUsersOfOneStride *>::iterator I = IU->IVUsesByStride.find(CondStride); if (I == IU->IVUsesByStride.end()) return Cond; + if (I->second->Users.size() > 1) { for (ilist<IVStrideUse>::iterator II = I->second->Users.begin(), EE = I->second->Users.end(); II != EE; ++II) { @@ -1839,6 +1840,7 @@ ICmpInst *LoopStrengthReduce::ChangeCompareStride(Loop *L, ICmpInst *Cond, return Cond; } } + // Only handle constant strides for now. const SCEVConstant *SC = dyn_cast<SCEVConstant>(CondStride); if (!SC) return Cond; @@ -1860,8 +1862,7 @@ ICmpInst *LoopStrengthReduce::ChangeCompareStride(Loop *L, ICmpInst *Cond, if (ConstantInt *C = dyn_cast<ConstantInt>(Cond->getOperand(1))) { int64_t CmpVal = C->getValue().getSExtValue(); - // Check the relevant induction variable for conformance to - // the pattern. + // Check the relevant induction variable for conformance to the pattern. const SCEV *IV = SE->getSCEV(Cond->getOperand(0)); const SCEVAddRecExpr *AR = dyn_cast<SCEVAddRecExpr>(IV); if (!AR || !AR->isAffine()) |
