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-rw-r--r--polly/lib/Support/SCEVAffinator.cpp186
1 files changed, 79 insertions, 107 deletions
diff --git a/polly/lib/Support/SCEVAffinator.cpp b/polly/lib/Support/SCEVAffinator.cpp
index 18223cbd52d..1a0e15c3d17 100644
--- a/polly/lib/Support/SCEVAffinator.cpp
+++ b/polly/lib/Support/SCEVAffinator.cpp
@@ -50,27 +50,12 @@ static isl_stat addNumBasicSets(__isl_take isl_set *Domain,
return isl_stat_ok;
}
-/// Helper to free a PWACtx object.
-static void freePWACtx(__isl_take PWACtx &PWAC) {
- isl_pw_aff_free(PWAC.first);
- isl_set_free(PWAC.second);
-}
-
-/// Helper to copy a PWACtx object.
-static __isl_give PWACtx copyPWACtx(const __isl_keep PWACtx &PWAC) {
- return std::make_pair(isl_pw_aff_copy(PWAC.first), isl_set_copy(PWAC.second));
-}
-
/// Determine if @p PWAC is too complex to continue.
-///
-/// Note that @p PWAC will be "free" (deallocated) if this function returns
-/// true, but not if this function returns false.
-static bool isTooComplex(PWACtx &PWAC) {
+static bool isTooComplex(PWACtx PWAC) {
unsigned NumBasicSets = 0;
- isl_pw_aff_foreach_piece(PWAC.first, addNumBasicSets, &NumBasicSets);
+ isl_pw_aff_foreach_piece(PWAC.first.keep(), addNumBasicSets, &NumBasicSets);
if (NumBasicSets <= MaxDisjunctionsInPwAff)
return false;
- freePWACtx(PWAC);
return true;
}
@@ -81,10 +66,12 @@ static SCEV::NoWrapFlags getNoWrapFlags(const SCEV *Expr) {
return SCEV::NoWrapMask;
}
-static void combine(__isl_keep PWACtx &PWAC0, const __isl_take PWACtx &PWAC1,
- isl_pw_aff *(Fn)(isl_pw_aff *, isl_pw_aff *)) {
- PWAC0.first = Fn(PWAC0.first, PWAC1.first);
- PWAC0.second = isl_set_union(PWAC0.second, PWAC1.second);
+static PWACtx combine(PWACtx PWAC0, PWACtx PWAC1,
+ __isl_give isl_pw_aff *(Fn)(__isl_take isl_pw_aff *,
+ __isl_take isl_pw_aff *)) {
+ PWAC0.first = isl::manage(Fn(PWAC0.first.take(), PWAC1.first.take()));
+ PWAC0.second = PWAC0.second.unite(PWAC1.second);
+ return PWAC0;
}
static __isl_give isl_pw_aff *getWidthExpValOnDomain(unsigned Width,
@@ -99,39 +86,33 @@ SCEVAffinator::SCEVAffinator(Scop *S, LoopInfo &LI)
: S(S), Ctx(S->getIslCtx().get()), SE(*S->getSE()), LI(LI),
TD(S->getFunction().getParent()->getDataLayout()) {}
-SCEVAffinator::~SCEVAffinator() {
- for (auto &CachedPair : CachedExpressions)
- freePWACtx(CachedPair.second);
-}
-
Loop *SCEVAffinator::getScope() { return BB ? LI.getLoopFor(BB) : nullptr; }
-void SCEVAffinator::interpretAsUnsigned(__isl_keep PWACtx &PWAC,
- unsigned Width) {
- auto *PWA = PWAC.first;
- auto *NonNegDom = isl_pw_aff_nonneg_set(isl_pw_aff_copy(PWA));
- auto *NonNegPWA = isl_pw_aff_intersect_domain(isl_pw_aff_copy(PWA),
- isl_set_copy(NonNegDom));
+void SCEVAffinator::interpretAsUnsigned(PWACtx &PWAC, unsigned Width) {
+ auto *NonNegDom = isl_pw_aff_nonneg_set(PWAC.first.copy());
+ auto *NonNegPWA =
+ isl_pw_aff_intersect_domain(PWAC.first.copy(), isl_set_copy(NonNegDom));
auto *ExpPWA = getWidthExpValOnDomain(Width, isl_set_complement(NonNegDom));
- PWAC.first = isl_pw_aff_union_add(NonNegPWA, isl_pw_aff_add(PWA, ExpPWA));
+ PWAC.first = isl::manage(isl_pw_aff_union_add(
+ NonNegPWA, isl_pw_aff_add(PWAC.first.take(), ExpPWA)));
}
void SCEVAffinator::takeNonNegativeAssumption(PWACtx &PWAC) {
- auto *NegPWA = isl_pw_aff_neg(isl_pw_aff_copy(PWAC.first));
+ auto *NegPWA = isl_pw_aff_neg(PWAC.first.copy());
auto *NegDom = isl_pw_aff_pos_set(NegPWA);
- PWAC.second = isl_set_union(PWAC.second, isl_set_copy(NegDom));
+ PWAC.second =
+ isl::manage(isl_set_union(PWAC.second.take(), isl_set_copy(NegDom)));
auto *Restriction = BB ? NegDom : isl_set_params(NegDom);
auto DL = BB ? BB->getTerminator()->getDebugLoc() : DebugLoc();
S->recordAssumption(UNSIGNED, isl::manage(Restriction), DL, AS_RESTRICTION,
BB);
}
-__isl_give PWACtx SCEVAffinator::getPWACtxFromPWA(__isl_take isl_pw_aff *PWA) {
- return std::make_pair(
- PWA, isl_set_empty(isl_space_set_alloc(Ctx, 0, NumIterators)));
+PWACtx SCEVAffinator::getPWACtxFromPWA(isl::pw_aff PWA) {
+ return std::make_pair(PWA, isl::set::empty(isl::space(Ctx, 0, NumIterators)));
}
-__isl_give PWACtx SCEVAffinator::getPwAff(const SCEV *Expr, BasicBlock *BB) {
+PWACtx SCEVAffinator::getPwAff(const SCEV *Expr, BasicBlock *BB) {
this->BB = BB;
if (BB) {
@@ -144,8 +125,7 @@ __isl_give PWACtx SCEVAffinator::getPwAff(const SCEV *Expr, BasicBlock *BB) {
return visit(Expr);
}
-__isl_give PWACtx SCEVAffinator::checkForWrapping(const SCEV *Expr,
- PWACtx PWAC) const {
+PWACtx SCEVAffinator::checkForWrapping(const SCEV *Expr, PWACtx PWAC) const {
// If the SCEV flags do contain NSW (no signed wrap) then PWA already
// represents Expr in modulo semantic (it is not allowed to overflow), thus we
// are done. Otherwise, we will compute:
@@ -156,42 +136,33 @@ __isl_give PWACtx SCEVAffinator::checkForWrapping(const SCEV *Expr,
if (IgnoreIntegerWrapping || (getNoWrapFlags(Expr) & SCEV::FlagNSW))
return PWAC;
- auto *PWA = PWAC.first;
- auto *PWAMod = addModuloSemantic(isl_pw_aff_copy(PWA), Expr->getType());
- auto *NotEqualSet = isl_pw_aff_ne_set(isl_pw_aff_copy(PWA), PWAMod);
- PWAC.second = isl_set_union(PWAC.second, isl_set_copy(NotEqualSet));
- PWAC.second = isl_set_coalesce(PWAC.second);
+ isl::pw_aff PWAMod = addModuloSemantic(PWAC.first, Expr->getType());
+
+ isl::set NotEqualSet = PWAC.first.ne_set(PWAMod);
+ PWAC.second = PWAC.second.unite(NotEqualSet).coalesce();
const DebugLoc &Loc = BB ? BB->getTerminator()->getDebugLoc() : DebugLoc();
- NotEqualSet = BB ? NotEqualSet : isl_set_params(NotEqualSet);
- NotEqualSet = isl_set_coalesce(NotEqualSet);
+ if (!BB)
+ NotEqualSet = NotEqualSet.params();
+ NotEqualSet = NotEqualSet.coalesce();
- if (isl_set_is_empty(NotEqualSet))
- isl_set_free(NotEqualSet);
- else
- S->recordAssumption(WRAPPING, isl::manage(NotEqualSet), Loc, AS_RESTRICTION,
- BB);
+ if (!NotEqualSet.is_empty())
+ S->recordAssumption(WRAPPING, NotEqualSet, Loc, AS_RESTRICTION, BB);
return PWAC;
}
-__isl_give isl_pw_aff *
-SCEVAffinator::addModuloSemantic(__isl_take isl_pw_aff *PWA,
- Type *ExprType) const {
+isl::pw_aff SCEVAffinator::addModuloSemantic(isl::pw_aff PWA,
+ Type *ExprType) const {
unsigned Width = TD.getTypeSizeInBits(ExprType);
- isl_ctx *Ctx = isl_pw_aff_get_ctx(PWA);
-
- isl_val *ModVal = isl_val_int_from_ui(Ctx, Width);
- ModVal = isl_val_2exp(ModVal);
- isl_set *Domain = isl_pw_aff_domain(isl_pw_aff_copy(PWA));
- isl_pw_aff *AddPW = getWidthExpValOnDomain(Width - 1, Domain);
+ auto ModVal = isl::val::int_from_ui(Ctx, Width);
+ ModVal = ModVal.two_exp();
- PWA = isl_pw_aff_add(PWA, isl_pw_aff_copy(AddPW));
- PWA = isl_pw_aff_mod_val(PWA, ModVal);
- PWA = isl_pw_aff_sub(PWA, AddPW);
-
- return PWA;
+ isl::set Domain = PWA.domain();
+ isl::pw_aff AddPW =
+ isl::manage(getWidthExpValOnDomain(Width - 1, Domain.take()));
+ return PWA.add(AddPW).mod(ModVal).sub(AddPW);
}
bool SCEVAffinator::hasNSWAddRecForLoop(Loop *L) const {
@@ -217,12 +188,12 @@ bool SCEVAffinator::computeModuloForExpr(const SCEV *Expr) {
return Width <= MaxSmallBitWidth;
}
-__isl_give PWACtx SCEVAffinator::visit(const SCEV *Expr) {
+PWACtx SCEVAffinator::visit(const SCEV *Expr) {
auto Key = std::make_pair(Expr, BB);
PWACtx PWAC = CachedExpressions[Key];
if (PWAC.first)
- return copyPWACtx(PWAC);
+ return PWAC;
auto ConstantAndLeftOverPair = extractConstantFactor(Expr, SE);
auto *Factor = ConstantAndLeftOverPair.first;
@@ -236,14 +207,14 @@ __isl_give PWACtx SCEVAffinator::visit(const SCEV *Expr) {
// to treat subexpressions that we cannot translate into an piecewise affine
// expression, as constant parameters of the piecewise affine expression.
if (isl_id *Id = S->getIdForParam(Expr).release()) {
- isl_space *Space = isl_space_set_alloc(Ctx, 1, NumIterators);
+ isl_space *Space = isl_space_set_alloc(Ctx.get(), 1, NumIterators);
Space = isl_space_set_dim_id(Space, isl_dim_param, 0, Id);
isl_set *Domain = isl_set_universe(isl_space_copy(Space));
isl_aff *Affine = isl_aff_zero_on_domain(isl_local_space_from_space(Space));
Affine = isl_aff_add_coefficient_si(Affine, isl_dim_param, 0, 1);
- PWAC = getPWACtxFromPWA(isl_pw_aff_alloc(Domain, Affine));
+ PWAC = getPWACtxFromPWA(isl::manage(isl_pw_aff_alloc(Domain, Affine)));
} else {
PWAC = SCEVVisitor<SCEVAffinator, PWACtx>::visit(Expr);
if (computeModuloForExpr(Expr))
@@ -253,22 +224,22 @@ __isl_give PWACtx SCEVAffinator::visit(const SCEV *Expr) {
}
if (!Factor->getType()->isIntegerTy(1)) {
- combine(PWAC, visitConstant(Factor), isl_pw_aff_mul);
+ PWAC = combine(PWAC, visitConstant(Factor), isl_pw_aff_mul);
if (computeModuloForExpr(Key.first))
PWAC.first = addModuloSemantic(PWAC.first, Expr->getType());
}
// For compile time reasons we need to simplify the PWAC before we cache and
// return it.
- PWAC.first = isl_pw_aff_coalesce(PWAC.first);
+ PWAC.first = PWAC.first.coalesce();
if (!computeModuloForExpr(Key.first))
PWAC = checkForWrapping(Key.first, PWAC);
- CachedExpressions[Key] = copyPWACtx(PWAC);
+ CachedExpressions[Key] = PWAC;
return PWAC;
}
-__isl_give PWACtx SCEVAffinator::visitConstant(const SCEVConstant *Expr) {
+PWACtx SCEVAffinator::visitConstant(const SCEVConstant *Expr) {
ConstantInt *Value = Expr->getValue();
isl_val *v;
@@ -282,14 +253,15 @@ __isl_give PWACtx SCEVAffinator::visitConstant(const SCEVConstant *Expr) {
// demand.
// 2. We pass down the signedness of the calculation and use it to interpret
// this constant correctly.
- v = isl_valFromAPInt(Ctx, Value->getValue(), /* isSigned */ true);
+ v = isl_valFromAPInt(Ctx.get(), Value->getValue(), /* isSigned */ true);
- isl_space *Space = isl_space_set_alloc(Ctx, 0, NumIterators);
+ isl_space *Space = isl_space_set_alloc(Ctx.get(), 0, NumIterators);
isl_local_space *ls = isl_local_space_from_space(Space);
- return getPWACtxFromPWA(isl_pw_aff_from_aff(isl_aff_val_on_domain(ls, v)));
+ return getPWACtxFromPWA(
+ isl::manage(isl_pw_aff_from_aff(isl_aff_val_on_domain(ls, v))));
}
-__isl_give PWACtx
+PWACtx
SCEVAffinator::visitTruncateExpr(const SCEVTruncateExpr *Expr) {
// Truncate operations are basically modulo operations, thus we can
// model them that way. However, for large types we assume the operand
@@ -304,14 +276,15 @@ SCEVAffinator::visitTruncateExpr(const SCEVTruncateExpr *Expr) {
if (computeModuloForExpr(Expr))
return OpPWAC;
- auto *Dom = isl_pw_aff_domain(isl_pw_aff_copy(OpPWAC.first));
+ auto *Dom = OpPWAC.first.domain().take();
auto *ExpPWA = getWidthExpValOnDomain(Width - 1, Dom);
auto *GreaterDom =
- isl_pw_aff_ge_set(isl_pw_aff_copy(OpPWAC.first), isl_pw_aff_copy(ExpPWA));
+ isl_pw_aff_ge_set(OpPWAC.first.copy(), isl_pw_aff_copy(ExpPWA));
auto *SmallerDom =
- isl_pw_aff_lt_set(isl_pw_aff_copy(OpPWAC.first), isl_pw_aff_neg(ExpPWA));
+ isl_pw_aff_lt_set(OpPWAC.first.copy(), isl_pw_aff_neg(ExpPWA));
auto *OutOfBoundsDom = isl_set_union(SmallerDom, GreaterDom);
- OpPWAC.second = isl_set_union(OpPWAC.second, isl_set_copy(OutOfBoundsDom));
+ OpPWAC.second =
+ OpPWAC.second.unite(isl::manage(isl_set_copy(OutOfBoundsDom)));
if (!BB) {
assert(isl_set_dim(OutOfBoundsDom, isl_dim_set) == 0 &&
@@ -325,7 +298,7 @@ SCEVAffinator::visitTruncateExpr(const SCEVTruncateExpr *Expr) {
return OpPWAC;
}
-__isl_give PWACtx
+PWACtx
SCEVAffinator::visitZeroExtendExpr(const SCEVZeroExtendExpr *Expr) {
// A zero-extended value can be interpreted as a piecewise defined signed
// value. If the value was non-negative it stays the same, otherwise it
@@ -386,17 +359,16 @@ SCEVAffinator::visitZeroExtendExpr(const SCEVZeroExtendExpr *Expr) {
return OpPWAC;
}
-__isl_give PWACtx
-SCEVAffinator::visitSignExtendExpr(const SCEVSignExtendExpr *Expr) {
+PWACtx SCEVAffinator::visitSignExtendExpr(const SCEVSignExtendExpr *Expr) {
// As all values are represented as signed, a sign extension is a noop.
return visit(Expr->getOperand());
}
-__isl_give PWACtx SCEVAffinator::visitAddExpr(const SCEVAddExpr *Expr) {
+PWACtx SCEVAffinator::visitAddExpr(const SCEVAddExpr *Expr) {
PWACtx Sum = visit(Expr->getOperand(0));
for (int i = 1, e = Expr->getNumOperands(); i < e; ++i) {
- combine(Sum, visit(Expr->getOperand(i)), isl_pw_aff_add);
+ Sum = combine(Sum, visit(Expr->getOperand(i)), isl_pw_aff_add);
if (isTooComplex(Sum))
return std::make_pair(nullptr, nullptr);
}
@@ -404,11 +376,11 @@ __isl_give PWACtx SCEVAffinator::visitAddExpr(const SCEVAddExpr *Expr) {
return Sum;
}
-__isl_give PWACtx SCEVAffinator::visitMulExpr(const SCEVMulExpr *Expr) {
+PWACtx SCEVAffinator::visitMulExpr(const SCEVMulExpr *Expr) {
PWACtx Prod = visit(Expr->getOperand(0));
for (int i = 1, e = Expr->getNumOperands(); i < e; ++i) {
- combine(Prod, visit(Expr->getOperand(i)), isl_pw_aff_mul);
+ Prod = combine(Prod, visit(Expr->getOperand(i)), isl_pw_aff_mul);
if (isTooComplex(Prod))
return std::make_pair(nullptr, nullptr);
}
@@ -416,7 +388,7 @@ __isl_give PWACtx SCEVAffinator::visitMulExpr(const SCEVMulExpr *Expr) {
return Prod;
}
-__isl_give PWACtx SCEVAffinator::visitAddRecExpr(const SCEVAddRecExpr *Expr) {
+PWACtx SCEVAffinator::visitAddRecExpr(const SCEVAddRecExpr *Expr) {
assert(Expr->isAffine() && "Only affine AddRecurrences allowed");
auto Flags = Expr->getNoWrapFlags();
@@ -427,7 +399,7 @@ __isl_give PWACtx SCEVAffinator::visitAddRecExpr(const SCEVAddRecExpr *Expr) {
"Scop does not contain the loop referenced in this AddRec");
PWACtx Step = visit(Expr->getOperand(1));
- isl_space *Space = isl_space_set_alloc(Ctx, 0, NumIterators);
+ isl_space *Space = isl_space_set_alloc(Ctx.get(), 0, NumIterators);
isl_local_space *LocalSpace = isl_local_space_from_space(Space);
unsigned loopDimension = S->getRelativeLoopDepth(Expr->getLoop());
@@ -436,7 +408,7 @@ __isl_give PWACtx SCEVAffinator::visitAddRecExpr(const SCEVAddRecExpr *Expr) {
isl_aff_zero_on_domain(LocalSpace), isl_dim_in, loopDimension, 1);
isl_pw_aff *LPwAff = isl_pw_aff_from_aff(LAff);
- Step.first = isl_pw_aff_mul(Step.first, LPwAff);
+ Step.first = Step.first.mul(isl::manage(LPwAff));
return Step;
}
@@ -451,15 +423,15 @@ __isl_give PWACtx SCEVAffinator::visitAddRecExpr(const SCEVAddRecExpr *Expr) {
PWACtx Result = visit(ZeroStartExpr);
PWACtx Start = visit(Expr->getStart());
- combine(Result, Start, isl_pw_aff_add);
+ Result = combine(Result, Start, isl_pw_aff_add);
return Result;
}
-__isl_give PWACtx SCEVAffinator::visitSMaxExpr(const SCEVSMaxExpr *Expr) {
+PWACtx SCEVAffinator::visitSMaxExpr(const SCEVSMaxExpr *Expr) {
PWACtx Max = visit(Expr->getOperand(0));
for (int i = 1, e = Expr->getNumOperands(); i < e; ++i) {
- combine(Max, visit(Expr->getOperand(i)), isl_pw_aff_max);
+ Max = combine(Max, visit(Expr->getOperand(i)), isl_pw_aff_max);
if (isTooComplex(Max))
return std::make_pair(nullptr, nullptr);
}
@@ -467,11 +439,11 @@ __isl_give PWACtx SCEVAffinator::visitSMaxExpr(const SCEVSMaxExpr *Expr) {
return Max;
}
-__isl_give PWACtx SCEVAffinator::visitUMaxExpr(const SCEVUMaxExpr *Expr) {
+PWACtx SCEVAffinator::visitUMaxExpr(const SCEVUMaxExpr *Expr) {
llvm_unreachable("SCEVUMaxExpr not yet supported");
}
-__isl_give PWACtx SCEVAffinator::visitUDivExpr(const SCEVUDivExpr *Expr) {
+PWACtx SCEVAffinator::visitUDivExpr(const SCEVUDivExpr *Expr) {
// The handling of unsigned division is basically the same as for signed
// division, except the interpretation of the operands. As the divisor
// has to be constant in both cases we can simply interpret it as an
@@ -492,9 +464,9 @@ __isl_give PWACtx SCEVAffinator::visitUDivExpr(const SCEVUDivExpr *Expr) {
// piece-wise defined value described for zero-extends as we already know
// the actual value of the constant divisor.
unsigned Width = TD.getTypeSizeInBits(Expr->getType());
- auto *DivisorDom = isl_pw_aff_domain(isl_pw_aff_copy(DivisorPWAC.first));
+ auto *DivisorDom = DivisorPWAC.first.domain().take();
auto *WidthExpPWA = getWidthExpValOnDomain(Width, DivisorDom);
- DivisorPWAC.first = isl_pw_aff_add(DivisorPWAC.first, WidthExpPWA);
+ DivisorPWAC.first = DivisorPWAC.first.add(isl::manage(WidthExpPWA));
}
// TODO: One can represent the dividend as piece-wise function to be more
@@ -503,13 +475,13 @@ __isl_give PWACtx SCEVAffinator::visitUDivExpr(const SCEVUDivExpr *Expr) {
// Assume a non-negative dividend.
takeNonNegativeAssumption(DividendPWAC);
- combine(DividendPWAC, DivisorPWAC, isl_pw_aff_div);
- DividendPWAC.first = isl_pw_aff_floor(DividendPWAC.first);
+ DividendPWAC = combine(DividendPWAC, DivisorPWAC, isl_pw_aff_div);
+ DividendPWAC.first = DividendPWAC.first.floor();
return DividendPWAC;
}
-__isl_give PWACtx SCEVAffinator::visitSDivInstruction(Instruction *SDiv) {
+PWACtx SCEVAffinator::visitSDivInstruction(Instruction *SDiv) {
assert(SDiv->getOpcode() == Instruction::SDiv && "Assumed SDiv instruction!");
auto *Scope = getScope();
@@ -522,11 +494,11 @@ __isl_give PWACtx SCEVAffinator::visitSDivInstruction(Instruction *SDiv) {
auto *Dividend = SDiv->getOperand(0);
auto *DividendSCEV = SE.getSCEVAtScope(Dividend, Scope);
auto DividendPWAC = visit(DividendSCEV);
- combine(DividendPWAC, DivisorPWAC, isl_pw_aff_tdiv_q);
+ DividendPWAC = combine(DividendPWAC, DivisorPWAC, isl_pw_aff_tdiv_q);
return DividendPWAC;
}
-__isl_give PWACtx SCEVAffinator::visitSRemInstruction(Instruction *SRem) {
+PWACtx SCEVAffinator::visitSRemInstruction(Instruction *SRem) {
assert(SRem->getOpcode() == Instruction::SRem && "Assumed SRem instruction!");
auto *Scope = getScope();
@@ -539,11 +511,11 @@ __isl_give PWACtx SCEVAffinator::visitSRemInstruction(Instruction *SRem) {
auto *Dividend = SRem->getOperand(0);
auto *DividendSCEV = SE.getSCEVAtScope(Dividend, Scope);
auto DividendPWAC = visit(DividendSCEV);
- combine(DividendPWAC, DivisorPWAC, isl_pw_aff_tdiv_r);
+ DividendPWAC = combine(DividendPWAC, DivisorPWAC, isl_pw_aff_tdiv_r);
return DividendPWAC;
}
-__isl_give PWACtx SCEVAffinator::visitUnknown(const SCEVUnknown *Expr) {
+PWACtx SCEVAffinator::visitUnknown(const SCEVUnknown *Expr) {
if (Instruction *I = dyn_cast<Instruction>(Expr->getValue())) {
switch (I->getOpcode()) {
case Instruction::IntToPtr:
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