2 * Copyright 2011 Leiden University. All rights reserved.
3 * Copyright 2012 Ecole Normale Superieure. All rights reserved.
5 * Redistribution and use in source and binary forms, with or without
6 * modification, are permitted provided that the following conditions
9 * 1. Redistributions of source code must retain the above copyright
10 * notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above
13 * copyright notice, this list of conditions and the following
14 * disclaimer in the documentation and/or other materials provided
15 * with the distribution.
17 * THIS SOFTWARE IS PROVIDED BY LEIDEN UNIVERSITY ''AS IS'' AND ANY
18 * EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR
20 * PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL LEIDEN UNIVERSITY OR
21 * CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL,
22 * EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO,
23 * PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA,
24 * OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
25 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
26 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
27 * OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29 * The views and conclusions contained in the software and documentation
30 * are those of the authors and should not be interpreted as
31 * representing official policies, either expressed or implied, of
38 #include <clang/AST/ASTContext.h>
39 #include <clang/AST/ASTDiagnostic.h>
40 #include <clang/AST/Expr.h>
41 #include <clang/AST/RecursiveASTVisitor.h>
44 #include <isl/space.h>
51 #include "scop_plus.h"
56 using namespace clang
;
58 #if defined(DECLREFEXPR_CREATE_REQUIRES_BOOL)
59 static DeclRefExpr
*create_DeclRefExpr(VarDecl
*var
)
61 return DeclRefExpr::Create(var
->getASTContext(), var
->getQualifierLoc(),
62 SourceLocation(), var
, false, var
->getInnerLocStart(),
63 var
->getType(), VK_LValue
);
65 #elif defined(DECLREFEXPR_CREATE_REQUIRES_SOURCELOCATION)
66 static DeclRefExpr
*create_DeclRefExpr(VarDecl
*var
)
68 return DeclRefExpr::Create(var
->getASTContext(), var
->getQualifierLoc(),
69 SourceLocation(), var
, var
->getInnerLocStart(), var
->getType(),
73 static DeclRefExpr
*create_DeclRefExpr(VarDecl
*var
)
75 return DeclRefExpr::Create(var
->getASTContext(), var
->getQualifierLoc(),
76 var
, var
->getInnerLocStart(), var
->getType(), VK_LValue
);
80 /* Check if the element type corresponding to the given array type
81 * has a const qualifier.
83 static bool const_base(QualType qt
)
85 const Type
*type
= qt
.getTypePtr();
87 if (type
->isPointerType())
88 return const_base(type
->getPointeeType());
89 if (type
->isArrayType()) {
90 const ArrayType
*atype
;
91 type
= type
->getCanonicalTypeInternal().getTypePtr();
92 atype
= cast
<ArrayType
>(type
);
93 return const_base(atype
->getElementType());
96 return qt
.isConstQualified();
99 /* Mark "decl" as having an unknown value in "assigned_value".
101 * If no (known or unknown) value was assigned to "decl" before,
102 * then it may have been treated as a parameter before and may
103 * therefore appear in a value assigned to another variable.
104 * If so, this assignment needs to be turned into an unknown value too.
106 static void clear_assignment(map
<ValueDecl
*, isl_pw_aff
*> &assigned_value
,
109 map
<ValueDecl
*, isl_pw_aff
*>::iterator it
;
111 it
= assigned_value
.find(decl
);
113 assigned_value
[decl
] = NULL
;
115 if (it
== assigned_value
.end())
118 for (it
= assigned_value
.begin(); it
!= assigned_value
.end(); ++it
) {
119 isl_pw_aff
*pa
= it
->second
;
120 int nparam
= isl_pw_aff_dim(pa
, isl_dim_param
);
122 for (int i
= 0; i
< nparam
; ++i
) {
125 if (!isl_pw_aff_has_dim_id(pa
, isl_dim_param
, i
))
127 id
= isl_pw_aff_get_dim_id(pa
, isl_dim_param
, i
);
128 if (isl_id_get_user(id
) == decl
)
135 /* Look for any assignments to scalar variables in part of the parse
136 * tree and set assigned_value to NULL for each of them.
137 * Also reset assigned_value if the address of a scalar variable
138 * is being taken. As an exception, if the address is passed to a function
139 * that is declared to receive a const pointer, then assigned_value is
142 * This ensures that we won't use any previously stored value
143 * in the current subtree and its parents.
145 struct clear_assignments
: RecursiveASTVisitor
<clear_assignments
> {
146 map
<ValueDecl
*, isl_pw_aff
*> &assigned_value
;
147 set
<UnaryOperator
*> skip
;
149 clear_assignments(map
<ValueDecl
*, isl_pw_aff
*> &assigned_value
) :
150 assigned_value(assigned_value
) {}
152 /* Check for "address of" operators whose value is passed
153 * to a const pointer argument and add them to "skip", so that
154 * we can skip them in VisitUnaryOperator.
156 bool VisitCallExpr(CallExpr
*expr
) {
158 fd
= expr
->getDirectCallee();
161 for (int i
= 0; i
< expr
->getNumArgs(); ++i
) {
162 Expr
*arg
= expr
->getArg(i
);
164 if (arg
->getStmtClass() == Stmt::ImplicitCastExprClass
) {
165 ImplicitCastExpr
*ice
;
166 ice
= cast
<ImplicitCastExpr
>(arg
);
167 arg
= ice
->getSubExpr();
169 if (arg
->getStmtClass() != Stmt::UnaryOperatorClass
)
171 op
= cast
<UnaryOperator
>(arg
);
172 if (op
->getOpcode() != UO_AddrOf
)
174 if (const_base(fd
->getParamDecl(i
)->getType()))
180 bool VisitUnaryOperator(UnaryOperator
*expr
) {
185 switch (expr
->getOpcode()) {
195 if (skip
.find(expr
) != skip
.end())
198 arg
= expr
->getSubExpr();
199 if (arg
->getStmtClass() != Stmt::DeclRefExprClass
)
201 ref
= cast
<DeclRefExpr
>(arg
);
202 decl
= ref
->getDecl();
203 clear_assignment(assigned_value
, decl
);
207 bool VisitBinaryOperator(BinaryOperator
*expr
) {
212 if (!expr
->isAssignmentOp())
214 lhs
= expr
->getLHS();
215 if (lhs
->getStmtClass() != Stmt::DeclRefExprClass
)
217 ref
= cast
<DeclRefExpr
>(lhs
);
218 decl
= ref
->getDecl();
219 clear_assignment(assigned_value
, decl
);
224 /* Keep a copy of the currently assigned values.
226 * Any variable that is assigned a value inside the current scope
227 * is removed again when we leave the scope (either because it wasn't
228 * stored in the cache or because it has a different value in the cache).
230 struct assigned_value_cache
{
231 map
<ValueDecl
*, isl_pw_aff
*> &assigned_value
;
232 map
<ValueDecl
*, isl_pw_aff
*> cache
;
234 assigned_value_cache(map
<ValueDecl
*, isl_pw_aff
*> &assigned_value
) :
235 assigned_value(assigned_value
), cache(assigned_value
) {}
236 ~assigned_value_cache() {
237 map
<ValueDecl
*, isl_pw_aff
*>::iterator it
= cache
.begin();
238 for (it
= assigned_value
.begin(); it
!= assigned_value
.end();
241 (cache
.find(it
->first
) != cache
.end() &&
242 cache
[it
->first
] != it
->second
))
243 cache
[it
->first
] = NULL
;
245 assigned_value
= cache
;
249 /* Insert an expression into the collection of expressions,
250 * provided it is not already in there.
251 * The isl_pw_affs are freed in the destructor.
253 void PetScan::insert_expression(__isl_take isl_pw_aff
*expr
)
255 std::set
<isl_pw_aff
*>::iterator it
;
257 if (expressions
.find(expr
) == expressions
.end())
258 expressions
.insert(expr
);
260 isl_pw_aff_free(expr
);
265 std::set
<isl_pw_aff
*>::iterator it
;
267 for (it
= expressions
.begin(); it
!= expressions
.end(); ++it
)
268 isl_pw_aff_free(*it
);
270 isl_union_map_free(value_bounds
);
273 /* Called if we found something we (currently) cannot handle.
274 * We'll provide more informative warnings later.
276 * We only actually complain if autodetect is false.
278 void PetScan::unsupported(Stmt
*stmt
, const char *msg
)
280 if (options
->autodetect
)
283 SourceLocation loc
= stmt
->getLocStart();
284 DiagnosticsEngine
&diag
= PP
.getDiagnostics();
285 unsigned id
= diag
.getCustomDiagID(DiagnosticsEngine::Warning
,
286 msg
? msg
: "unsupported");
287 DiagnosticBuilder B
= diag
.Report(loc
, id
) << stmt
->getSourceRange();
290 /* Extract an integer from "expr" and store it in "v".
292 int PetScan::extract_int(IntegerLiteral
*expr
, isl_int
*v
)
294 const Type
*type
= expr
->getType().getTypePtr();
295 int is_signed
= type
->hasSignedIntegerRepresentation();
298 int64_t i
= expr
->getValue().getSExtValue();
299 isl_int_set_si(*v
, i
);
301 uint64_t i
= expr
->getValue().getZExtValue();
302 isl_int_set_ui(*v
, i
);
308 /* Extract an integer from "expr" and store it in "v".
309 * Return -1 if "expr" does not (obviously) represent an integer.
311 int PetScan::extract_int(clang::ParenExpr
*expr
, isl_int
*v
)
313 return extract_int(expr
->getSubExpr(), v
);
316 /* Extract an integer from "expr" and store it in "v".
317 * Return -1 if "expr" does not (obviously) represent an integer.
319 int PetScan::extract_int(clang::Expr
*expr
, isl_int
*v
)
321 if (expr
->getStmtClass() == Stmt::IntegerLiteralClass
)
322 return extract_int(cast
<IntegerLiteral
>(expr
), v
);
323 if (expr
->getStmtClass() == Stmt::ParenExprClass
)
324 return extract_int(cast
<ParenExpr
>(expr
), v
);
330 /* Extract an affine expression from the IntegerLiteral "expr".
332 __isl_give isl_pw_aff
*PetScan::extract_affine(IntegerLiteral
*expr
)
334 isl_space
*dim
= isl_space_params_alloc(ctx
, 0);
335 isl_local_space
*ls
= isl_local_space_from_space(isl_space_copy(dim
));
336 isl_aff
*aff
= isl_aff_zero_on_domain(ls
);
337 isl_set
*dom
= isl_set_universe(dim
);
341 extract_int(expr
, &v
);
342 aff
= isl_aff_add_constant(aff
, v
);
345 return isl_pw_aff_alloc(dom
, aff
);
348 /* Extract an affine expression from the APInt "val".
350 __isl_give isl_pw_aff
*PetScan::extract_affine(const llvm::APInt
&val
)
352 isl_space
*dim
= isl_space_params_alloc(ctx
, 0);
353 isl_local_space
*ls
= isl_local_space_from_space(isl_space_copy(dim
));
354 isl_aff
*aff
= isl_aff_zero_on_domain(ls
);
355 isl_set
*dom
= isl_set_universe(dim
);
359 isl_int_set_ui(v
, val
.getZExtValue());
360 aff
= isl_aff_add_constant(aff
, v
);
363 return isl_pw_aff_alloc(dom
, aff
);
366 __isl_give isl_pw_aff
*PetScan::extract_affine(ImplicitCastExpr
*expr
)
368 return extract_affine(expr
->getSubExpr());
371 static unsigned get_type_size(ValueDecl
*decl
)
373 return decl
->getASTContext().getIntWidth(decl
->getType());
376 /* Bound parameter "pos" of "set" to the possible values of "decl".
378 static __isl_give isl_set
*set_parameter_bounds(__isl_take isl_set
*set
,
379 unsigned pos
, ValueDecl
*decl
)
386 width
= get_type_size(decl
);
387 if (decl
->getType()->isUnsignedIntegerType()) {
388 set
= isl_set_lower_bound_si(set
, isl_dim_param
, pos
, 0);
389 isl_int_set_si(v
, 1);
390 isl_int_mul_2exp(v
, v
, width
);
391 isl_int_sub_ui(v
, v
, 1);
392 set
= isl_set_upper_bound(set
, isl_dim_param
, pos
, v
);
394 isl_int_set_si(v
, 1);
395 isl_int_mul_2exp(v
, v
, width
- 1);
396 isl_int_sub_ui(v
, v
, 1);
397 set
= isl_set_upper_bound(set
, isl_dim_param
, pos
, v
);
399 isl_int_sub_ui(v
, v
, 1);
400 set
= isl_set_lower_bound(set
, isl_dim_param
, pos
, v
);
408 /* Extract an affine expression from the DeclRefExpr "expr".
410 * If the variable has been assigned a value, then we check whether
411 * we know what (affine) value was assigned.
412 * If so, we return this value. Otherwise we convert "expr"
413 * to an extra parameter (provided nesting_enabled is set).
415 * Otherwise, we simply return an expression that is equal
416 * to a parameter corresponding to the referenced variable.
418 __isl_give isl_pw_aff
*PetScan::extract_affine(DeclRefExpr
*expr
)
420 ValueDecl
*decl
= expr
->getDecl();
421 const Type
*type
= decl
->getType().getTypePtr();
427 if (!type
->isIntegerType()) {
432 if (assigned_value
.find(decl
) != assigned_value
.end()) {
433 if (assigned_value
[decl
])
434 return isl_pw_aff_copy(assigned_value
[decl
]);
436 return nested_access(expr
);
439 id
= isl_id_alloc(ctx
, decl
->getName().str().c_str(), decl
);
440 dim
= isl_space_params_alloc(ctx
, 1);
442 dim
= isl_space_set_dim_id(dim
, isl_dim_param
, 0, id
);
444 dom
= isl_set_universe(isl_space_copy(dim
));
445 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(dim
));
446 aff
= isl_aff_add_coefficient_si(aff
, isl_dim_param
, 0, 1);
448 return isl_pw_aff_alloc(dom
, aff
);
451 /* Extract an affine expression from an integer division operation.
452 * In particular, if "expr" is lhs/rhs, then return
454 * lhs >= 0 ? floor(lhs/rhs) : ceil(lhs/rhs)
456 * The second argument (rhs) is required to be a (positive) integer constant.
458 __isl_give isl_pw_aff
*PetScan::extract_affine_div(BinaryOperator
*expr
)
461 isl_pw_aff
*rhs
, *lhs
;
463 rhs
= extract_affine(expr
->getRHS());
464 is_cst
= isl_pw_aff_is_cst(rhs
);
465 if (is_cst
< 0 || !is_cst
) {
466 isl_pw_aff_free(rhs
);
472 lhs
= extract_affine(expr
->getLHS());
474 return isl_pw_aff_tdiv_q(lhs
, rhs
);
477 /* Extract an affine expression from a modulo operation.
478 * In particular, if "expr" is lhs/rhs, then return
480 * lhs - rhs * (lhs >= 0 ? floor(lhs/rhs) : ceil(lhs/rhs))
482 * The second argument (rhs) is required to be a (positive) integer constant.
484 __isl_give isl_pw_aff
*PetScan::extract_affine_mod(BinaryOperator
*expr
)
487 isl_pw_aff
*rhs
, *lhs
;
489 rhs
= extract_affine(expr
->getRHS());
490 is_cst
= isl_pw_aff_is_cst(rhs
);
491 if (is_cst
< 0 || !is_cst
) {
492 isl_pw_aff_free(rhs
);
498 lhs
= extract_affine(expr
->getLHS());
500 return isl_pw_aff_tdiv_r(lhs
, rhs
);
503 /* Extract an affine expression from a multiplication operation.
504 * This is only allowed if at least one of the two arguments
505 * is a (piecewise) constant.
507 __isl_give isl_pw_aff
*PetScan::extract_affine_mul(BinaryOperator
*expr
)
512 lhs
= extract_affine(expr
->getLHS());
513 rhs
= extract_affine(expr
->getRHS());
515 if (!isl_pw_aff_is_cst(lhs
) && !isl_pw_aff_is_cst(rhs
)) {
516 isl_pw_aff_free(lhs
);
517 isl_pw_aff_free(rhs
);
522 return isl_pw_aff_mul(lhs
, rhs
);
525 /* Extract an affine expression from an addition or subtraction operation.
527 __isl_give isl_pw_aff
*PetScan::extract_affine_add(BinaryOperator
*expr
)
532 lhs
= extract_affine(expr
->getLHS());
533 rhs
= extract_affine(expr
->getRHS());
535 switch (expr
->getOpcode()) {
537 return isl_pw_aff_add(lhs
, rhs
);
539 return isl_pw_aff_sub(lhs
, rhs
);
541 isl_pw_aff_free(lhs
);
542 isl_pw_aff_free(rhs
);
552 static __isl_give isl_pw_aff
*wrap(__isl_take isl_pw_aff
*pwaff
,
558 isl_int_set_si(mod
, 1);
559 isl_int_mul_2exp(mod
, mod
, width
);
561 pwaff
= isl_pw_aff_mod(pwaff
, mod
);
568 /* Limit the domain of "pwaff" to those elements where the function
571 * 2^{width-1} <= pwaff < 2^{width-1}
573 static __isl_give isl_pw_aff
*avoid_overflow(__isl_take isl_pw_aff
*pwaff
,
577 isl_space
*space
= isl_pw_aff_get_domain_space(pwaff
);
578 isl_local_space
*ls
= isl_local_space_from_space(space
);
584 isl_int_set_si(v
, 1);
585 isl_int_mul_2exp(v
, v
, width
- 1);
587 bound
= isl_aff_zero_on_domain(ls
);
588 bound
= isl_aff_add_constant(bound
, v
);
589 b
= isl_pw_aff_from_aff(bound
);
591 dom
= isl_pw_aff_lt_set(isl_pw_aff_copy(pwaff
), isl_pw_aff_copy(b
));
592 pwaff
= isl_pw_aff_intersect_domain(pwaff
, dom
);
594 b
= isl_pw_aff_neg(b
);
595 dom
= isl_pw_aff_ge_set(isl_pw_aff_copy(pwaff
), b
);
596 pwaff
= isl_pw_aff_intersect_domain(pwaff
, dom
);
603 /* Handle potential overflows on signed computations.
605 * If options->signed_overflow is set to PET_OVERFLOW_AVOID,
606 * the we adjust the domain of "pa" to avoid overflows.
608 __isl_give isl_pw_aff
*PetScan::signed_overflow(__isl_take isl_pw_aff
*pa
,
611 if (options
->signed_overflow
== PET_OVERFLOW_AVOID
)
612 pa
= avoid_overflow(pa
, width
);
617 /* Return the piecewise affine expression "set ? 1 : 0" defined on "dom".
619 static __isl_give isl_pw_aff
*indicator_function(__isl_take isl_set
*set
,
620 __isl_take isl_set
*dom
)
623 pa
= isl_set_indicator_function(set
);
624 pa
= isl_pw_aff_intersect_domain(pa
, dom
);
628 /* Extract an affine expression from some binary operations.
629 * If the result of the expression is unsigned, then we wrap it
630 * based on the size of the type. Otherwise, we ensure that
631 * no overflow occurs.
633 __isl_give isl_pw_aff
*PetScan::extract_affine(BinaryOperator
*expr
)
638 switch (expr
->getOpcode()) {
641 res
= extract_affine_add(expr
);
644 res
= extract_affine_div(expr
);
647 res
= extract_affine_mod(expr
);
650 res
= extract_affine_mul(expr
);
660 return extract_condition(expr
);
666 width
= ast_context
.getIntWidth(expr
->getType());
667 if (expr
->getType()->isUnsignedIntegerType())
668 res
= wrap(res
, width
);
670 res
= signed_overflow(res
, width
);
675 /* Extract an affine expression from a negation operation.
677 __isl_give isl_pw_aff
*PetScan::extract_affine(UnaryOperator
*expr
)
679 if (expr
->getOpcode() == UO_Minus
)
680 return isl_pw_aff_neg(extract_affine(expr
->getSubExpr()));
681 if (expr
->getOpcode() == UO_LNot
)
682 return extract_condition(expr
);
688 __isl_give isl_pw_aff
*PetScan::extract_affine(ParenExpr
*expr
)
690 return extract_affine(expr
->getSubExpr());
693 /* Extract an affine expression from some special function calls.
694 * In particular, we handle "min", "max", "ceild" and "floord".
695 * In case of the latter two, the second argument needs to be
696 * a (positive) integer constant.
698 __isl_give isl_pw_aff
*PetScan::extract_affine(CallExpr
*expr
)
702 isl_pw_aff
*aff1
, *aff2
;
704 fd
= expr
->getDirectCallee();
710 name
= fd
->getDeclName().getAsString();
711 if (!(expr
->getNumArgs() == 2 && name
== "min") &&
712 !(expr
->getNumArgs() == 2 && name
== "max") &&
713 !(expr
->getNumArgs() == 2 && name
== "floord") &&
714 !(expr
->getNumArgs() == 2 && name
== "ceild")) {
719 if (name
== "min" || name
== "max") {
720 aff1
= extract_affine(expr
->getArg(0));
721 aff2
= extract_affine(expr
->getArg(1));
724 aff1
= isl_pw_aff_min(aff1
, aff2
);
726 aff1
= isl_pw_aff_max(aff1
, aff2
);
727 } else if (name
== "floord" || name
== "ceild") {
729 Expr
*arg2
= expr
->getArg(1);
731 if (arg2
->getStmtClass() != Stmt::IntegerLiteralClass
) {
735 aff1
= extract_affine(expr
->getArg(0));
737 extract_int(cast
<IntegerLiteral
>(arg2
), &v
);
738 aff1
= isl_pw_aff_scale_down(aff1
, v
);
740 if (name
== "floord")
741 aff1
= isl_pw_aff_floor(aff1
);
743 aff1
= isl_pw_aff_ceil(aff1
);
752 /* This method is called when we come across an access that is
753 * nested in what is supposed to be an affine expression.
754 * If nesting is allowed, we return a new parameter that corresponds
755 * to this nested access. Otherwise, we simply complain.
757 * Note that we currently don't allow nested accesses themselves
758 * to contain any nested accesses, so we check if we can extract
759 * the access without any nesting and complain if we can't.
761 * The new parameter is resolved in resolve_nested.
763 isl_pw_aff
*PetScan::nested_access(Expr
*expr
)
771 if (!nesting_enabled
) {
776 allow_nested
= false;
777 access
= extract_access(expr
);
783 isl_map_free(access
);
785 id
= isl_id_alloc(ctx
, NULL
, expr
);
786 dim
= isl_space_params_alloc(ctx
, 1);
788 dim
= isl_space_set_dim_id(dim
, isl_dim_param
, 0, id
);
790 dom
= isl_set_universe(isl_space_copy(dim
));
791 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(dim
));
792 aff
= isl_aff_add_coefficient_si(aff
, isl_dim_param
, 0, 1);
794 return isl_pw_aff_alloc(dom
, aff
);
797 /* Affine expressions are not supposed to contain array accesses,
798 * but if nesting is allowed, we return a parameter corresponding
799 * to the array access.
801 __isl_give isl_pw_aff
*PetScan::extract_affine(ArraySubscriptExpr
*expr
)
803 return nested_access(expr
);
806 /* Extract an affine expression from a conditional operation.
808 __isl_give isl_pw_aff
*PetScan::extract_affine(ConditionalOperator
*expr
)
810 isl_pw_aff
*cond
, *lhs
, *rhs
, *res
;
812 cond
= extract_condition(expr
->getCond());
813 lhs
= extract_affine(expr
->getTrueExpr());
814 rhs
= extract_affine(expr
->getFalseExpr());
816 return isl_pw_aff_cond(cond
, lhs
, rhs
);
819 /* Extract an affine expression, if possible, from "expr".
820 * Otherwise return NULL.
822 __isl_give isl_pw_aff
*PetScan::extract_affine(Expr
*expr
)
824 switch (expr
->getStmtClass()) {
825 case Stmt::ImplicitCastExprClass
:
826 return extract_affine(cast
<ImplicitCastExpr
>(expr
));
827 case Stmt::IntegerLiteralClass
:
828 return extract_affine(cast
<IntegerLiteral
>(expr
));
829 case Stmt::DeclRefExprClass
:
830 return extract_affine(cast
<DeclRefExpr
>(expr
));
831 case Stmt::BinaryOperatorClass
:
832 return extract_affine(cast
<BinaryOperator
>(expr
));
833 case Stmt::UnaryOperatorClass
:
834 return extract_affine(cast
<UnaryOperator
>(expr
));
835 case Stmt::ParenExprClass
:
836 return extract_affine(cast
<ParenExpr
>(expr
));
837 case Stmt::CallExprClass
:
838 return extract_affine(cast
<CallExpr
>(expr
));
839 case Stmt::ArraySubscriptExprClass
:
840 return extract_affine(cast
<ArraySubscriptExpr
>(expr
));
841 case Stmt::ConditionalOperatorClass
:
842 return extract_affine(cast
<ConditionalOperator
>(expr
));
849 __isl_give isl_map
*PetScan::extract_access(ImplicitCastExpr
*expr
)
851 return extract_access(expr
->getSubExpr());
854 /* Return the depth of an array of the given type.
856 static int array_depth(const Type
*type
)
858 if (type
->isPointerType())
859 return 1 + array_depth(type
->getPointeeType().getTypePtr());
860 if (type
->isArrayType()) {
861 const ArrayType
*atype
;
862 type
= type
->getCanonicalTypeInternal().getTypePtr();
863 atype
= cast
<ArrayType
>(type
);
864 return 1 + array_depth(atype
->getElementType().getTypePtr());
869 /* Return the element type of the given array type.
871 static QualType
base_type(QualType qt
)
873 const Type
*type
= qt
.getTypePtr();
875 if (type
->isPointerType())
876 return base_type(type
->getPointeeType());
877 if (type
->isArrayType()) {
878 const ArrayType
*atype
;
879 type
= type
->getCanonicalTypeInternal().getTypePtr();
880 atype
= cast
<ArrayType
>(type
);
881 return base_type(atype
->getElementType());
886 /* Extract an access relation from a reference to a variable.
887 * If the variable has name "A" and its type corresponds to an
888 * array of depth d, then the returned access relation is of the
891 * { [] -> A[i_1,...,i_d] }
893 __isl_give isl_map
*PetScan::extract_access(DeclRefExpr
*expr
)
895 ValueDecl
*decl
= expr
->getDecl();
896 int depth
= array_depth(decl
->getType().getTypePtr());
897 isl_id
*id
= isl_id_alloc(ctx
, decl
->getName().str().c_str(), decl
);
898 isl_space
*dim
= isl_space_alloc(ctx
, 0, 0, depth
);
901 dim
= isl_space_set_tuple_id(dim
, isl_dim_out
, id
);
903 access_rel
= isl_map_universe(dim
);
908 /* Extract an access relation from an integer contant.
909 * If the value of the constant is "v", then the returned access relation
914 __isl_give isl_map
*PetScan::extract_access(IntegerLiteral
*expr
)
916 return isl_map_from_range(isl_set_from_pw_aff(extract_affine(expr
)));
919 /* Try and extract an access relation from the given Expr.
920 * Return NULL if it doesn't work out.
922 __isl_give isl_map
*PetScan::extract_access(Expr
*expr
)
924 switch (expr
->getStmtClass()) {
925 case Stmt::ImplicitCastExprClass
:
926 return extract_access(cast
<ImplicitCastExpr
>(expr
));
927 case Stmt::DeclRefExprClass
:
928 return extract_access(cast
<DeclRefExpr
>(expr
));
929 case Stmt::ArraySubscriptExprClass
:
930 return extract_access(cast
<ArraySubscriptExpr
>(expr
));
931 case Stmt::IntegerLiteralClass
:
932 return extract_access(cast
<IntegerLiteral
>(expr
));
939 /* Assign the affine expression "index" to the output dimension "pos" of "map",
940 * restrict the domain to those values that result in a non-negative index
941 * and return the result.
943 __isl_give isl_map
*set_index(__isl_take isl_map
*map
, int pos
,
944 __isl_take isl_pw_aff
*index
)
947 int len
= isl_map_dim(map
, isl_dim_out
);
951 domain
= isl_pw_aff_nonneg_set(isl_pw_aff_copy(index
));
952 index
= isl_pw_aff_intersect_domain(index
, domain
);
953 index_map
= isl_map_from_range(isl_set_from_pw_aff(index
));
954 index_map
= isl_map_insert_dims(index_map
, isl_dim_out
, 0, pos
);
955 index_map
= isl_map_add_dims(index_map
, isl_dim_out
, len
- pos
- 1);
956 id
= isl_map_get_tuple_id(map
, isl_dim_out
);
957 index_map
= isl_map_set_tuple_id(index_map
, isl_dim_out
, id
);
959 map
= isl_map_intersect(map
, index_map
);
964 /* Extract an access relation from the given array subscript expression.
965 * If nesting is allowed in general, then we turn it on while
966 * examining the index expression.
968 * We first extract an access relation from the base.
969 * This will result in an access relation with a range that corresponds
970 * to the array being accessed and with earlier indices filled in already.
971 * We then extract the current index and fill that in as well.
972 * The position of the current index is based on the type of base.
973 * If base is the actual array variable, then the depth of this type
974 * will be the same as the depth of the array and we will fill in
975 * the first array index.
976 * Otherwise, the depth of the base type will be smaller and we will fill
979 __isl_give isl_map
*PetScan::extract_access(ArraySubscriptExpr
*expr
)
981 Expr
*base
= expr
->getBase();
982 Expr
*idx
= expr
->getIdx();
984 isl_map
*base_access
;
986 int depth
= array_depth(base
->getType().getTypePtr());
988 bool save_nesting
= nesting_enabled
;
990 nesting_enabled
= allow_nested
;
992 base_access
= extract_access(base
);
993 index
= extract_affine(idx
);
995 nesting_enabled
= save_nesting
;
997 pos
= isl_map_dim(base_access
, isl_dim_out
) - depth
;
998 access
= set_index(base_access
, pos
, index
);
1003 /* Check if "expr" calls function "minmax" with two arguments and if so
1004 * make lhs and rhs refer to these two arguments.
1006 static bool is_minmax(Expr
*expr
, const char *minmax
, Expr
*&lhs
, Expr
*&rhs
)
1012 if (expr
->getStmtClass() != Stmt::CallExprClass
)
1015 call
= cast
<CallExpr
>(expr
);
1016 fd
= call
->getDirectCallee();
1020 if (call
->getNumArgs() != 2)
1023 name
= fd
->getDeclName().getAsString();
1027 lhs
= call
->getArg(0);
1028 rhs
= call
->getArg(1);
1033 /* Check if "expr" is of the form min(lhs, rhs) and if so make
1034 * lhs and rhs refer to the two arguments.
1036 static bool is_min(Expr
*expr
, Expr
*&lhs
, Expr
*&rhs
)
1038 return is_minmax(expr
, "min", lhs
, rhs
);
1041 /* Check if "expr" is of the form max(lhs, rhs) and if so make
1042 * lhs and rhs refer to the two arguments.
1044 static bool is_max(Expr
*expr
, Expr
*&lhs
, Expr
*&rhs
)
1046 return is_minmax(expr
, "max", lhs
, rhs
);
1049 /* Return "lhs && rhs", defined on the shared definition domain.
1051 static __isl_give isl_pw_aff
*pw_aff_and(__isl_take isl_pw_aff
*lhs
,
1052 __isl_take isl_pw_aff
*rhs
)
1057 dom
= isl_set_intersect(isl_pw_aff_domain(isl_pw_aff_copy(lhs
)),
1058 isl_pw_aff_domain(isl_pw_aff_copy(rhs
)));
1059 cond
= isl_set_intersect(isl_pw_aff_non_zero_set(lhs
),
1060 isl_pw_aff_non_zero_set(rhs
));
1061 return indicator_function(cond
, dom
);
1064 /* Return "lhs && rhs", with shortcut semantics.
1065 * That is, if lhs is false, then the result is defined even if rhs is not.
1066 * In practice, we compute lhs ? rhs : lhs.
1068 static __isl_give isl_pw_aff
*pw_aff_and_then(__isl_take isl_pw_aff
*lhs
,
1069 __isl_take isl_pw_aff
*rhs
)
1071 return isl_pw_aff_cond(isl_pw_aff_copy(lhs
), rhs
, lhs
);
1074 /* Return "lhs || rhs", with shortcut semantics.
1075 * That is, if lhs is true, then the result is defined even if rhs is not.
1076 * In practice, we compute lhs ? lhs : rhs.
1078 static __isl_give isl_pw_aff
*pw_aff_or_else(__isl_take isl_pw_aff
*lhs
,
1079 __isl_take isl_pw_aff
*rhs
)
1081 return isl_pw_aff_cond(isl_pw_aff_copy(lhs
), lhs
, rhs
);
1084 /* Extract an affine expressions representing the comparison "LHS op RHS"
1085 * "comp" is the original statement that "LHS op RHS" is derived from
1086 * and is used for diagnostics.
1088 * If the comparison is of the form
1092 * then the expression is constructed as the conjunction of
1097 * A similar optimization is performed for max(a,b) <= c.
1098 * We do this because that will lead to simpler representations
1099 * of the expression.
1100 * If isl is ever enhanced to explicitly deal with min and max expressions,
1101 * this optimization can be removed.
1103 __isl_give isl_pw_aff
*PetScan::extract_comparison(BinaryOperatorKind op
,
1104 Expr
*LHS
, Expr
*RHS
, Stmt
*comp
)
1113 return extract_comparison(BO_LT
, RHS
, LHS
, comp
);
1115 return extract_comparison(BO_LE
, RHS
, LHS
, comp
);
1117 if (op
== BO_LT
|| op
== BO_LE
) {
1118 Expr
*expr1
, *expr2
;
1119 if (is_min(RHS
, expr1
, expr2
)) {
1120 lhs
= extract_comparison(op
, LHS
, expr1
, comp
);
1121 rhs
= extract_comparison(op
, LHS
, expr2
, comp
);
1122 return pw_aff_and(lhs
, rhs
);
1124 if (is_max(LHS
, expr1
, expr2
)) {
1125 lhs
= extract_comparison(op
, expr1
, RHS
, comp
);
1126 rhs
= extract_comparison(op
, expr2
, RHS
, comp
);
1127 return pw_aff_and(lhs
, rhs
);
1131 lhs
= extract_affine(LHS
);
1132 rhs
= extract_affine(RHS
);
1134 dom
= isl_pw_aff_domain(isl_pw_aff_copy(lhs
));
1135 dom
= isl_set_intersect(dom
, isl_pw_aff_domain(isl_pw_aff_copy(rhs
)));
1139 cond
= isl_pw_aff_lt_set(lhs
, rhs
);
1142 cond
= isl_pw_aff_le_set(lhs
, rhs
);
1145 cond
= isl_pw_aff_eq_set(lhs
, rhs
);
1148 cond
= isl_pw_aff_ne_set(lhs
, rhs
);
1151 isl_pw_aff_free(lhs
);
1152 isl_pw_aff_free(rhs
);
1158 cond
= isl_set_coalesce(cond
);
1159 res
= indicator_function(cond
, dom
);
1164 __isl_give isl_pw_aff
*PetScan::extract_comparison(BinaryOperator
*comp
)
1166 return extract_comparison(comp
->getOpcode(), comp
->getLHS(),
1167 comp
->getRHS(), comp
);
1170 /* Extract an affine expression representing the negation (logical not)
1171 * of a subexpression.
1173 __isl_give isl_pw_aff
*PetScan::extract_boolean(UnaryOperator
*op
)
1175 isl_set
*set_cond
, *dom
;
1176 isl_pw_aff
*cond
, *res
;
1178 cond
= extract_condition(op
->getSubExpr());
1180 dom
= isl_pw_aff_domain(isl_pw_aff_copy(cond
));
1182 set_cond
= isl_pw_aff_zero_set(cond
);
1184 res
= indicator_function(set_cond
, dom
);
1189 /* Extract an affine expression representing the disjunction (logical or)
1190 * or conjunction (logical and) of two subexpressions.
1192 __isl_give isl_pw_aff
*PetScan::extract_boolean(BinaryOperator
*comp
)
1194 isl_pw_aff
*lhs
, *rhs
;
1196 lhs
= extract_condition(comp
->getLHS());
1197 rhs
= extract_condition(comp
->getRHS());
1199 switch (comp
->getOpcode()) {
1201 return pw_aff_and_then(lhs
, rhs
);
1203 return pw_aff_or_else(lhs
, rhs
);
1205 isl_pw_aff_free(lhs
);
1206 isl_pw_aff_free(rhs
);
1213 __isl_give isl_pw_aff
*PetScan::extract_condition(UnaryOperator
*expr
)
1215 switch (expr
->getOpcode()) {
1217 return extract_boolean(expr
);
1224 /* Extract the affine expression "expr != 0 ? 1 : 0".
1226 __isl_give isl_pw_aff
*PetScan::extract_implicit_condition(Expr
*expr
)
1231 res
= extract_affine(expr
);
1233 dom
= isl_pw_aff_domain(isl_pw_aff_copy(res
));
1234 set
= isl_pw_aff_non_zero_set(res
);
1236 res
= indicator_function(set
, dom
);
1241 /* Extract an affine expression from a boolean expression.
1242 * In particular, return the expression "expr ? 1 : 0".
1244 * If the expression doesn't look like a condition, we assume it
1245 * is an affine expression and return the condition "expr != 0 ? 1 : 0".
1247 __isl_give isl_pw_aff
*PetScan::extract_condition(Expr
*expr
)
1249 BinaryOperator
*comp
;
1252 isl_set
*u
= isl_set_universe(isl_space_params_alloc(ctx
, 0));
1253 return indicator_function(u
, isl_set_copy(u
));
1256 if (expr
->getStmtClass() == Stmt::ParenExprClass
)
1257 return extract_condition(cast
<ParenExpr
>(expr
)->getSubExpr());
1259 if (expr
->getStmtClass() == Stmt::UnaryOperatorClass
)
1260 return extract_condition(cast
<UnaryOperator
>(expr
));
1262 if (expr
->getStmtClass() != Stmt::BinaryOperatorClass
)
1263 return extract_implicit_condition(expr
);
1265 comp
= cast
<BinaryOperator
>(expr
);
1266 switch (comp
->getOpcode()) {
1273 return extract_comparison(comp
);
1276 return extract_boolean(comp
);
1278 return extract_implicit_condition(expr
);
1282 static enum pet_op_type
UnaryOperatorKind2pet_op_type(UnaryOperatorKind kind
)
1286 return pet_op_minus
;
1288 return pet_op_post_inc
;
1290 return pet_op_post_dec
;
1292 return pet_op_pre_inc
;
1294 return pet_op_pre_dec
;
1300 static enum pet_op_type
BinaryOperatorKind2pet_op_type(BinaryOperatorKind kind
)
1304 return pet_op_add_assign
;
1306 return pet_op_sub_assign
;
1308 return pet_op_mul_assign
;
1310 return pet_op_div_assign
;
1312 return pet_op_assign
;
1336 /* Construct a pet_expr representing a unary operator expression.
1338 struct pet_expr
*PetScan::extract_expr(UnaryOperator
*expr
)
1340 struct pet_expr
*arg
;
1341 enum pet_op_type op
;
1343 op
= UnaryOperatorKind2pet_op_type(expr
->getOpcode());
1344 if (op
== pet_op_last
) {
1349 arg
= extract_expr(expr
->getSubExpr());
1351 if (expr
->isIncrementDecrementOp() &&
1352 arg
&& arg
->type
== pet_expr_access
) {
1357 return pet_expr_new_unary(ctx
, op
, arg
);
1360 /* Mark the given access pet_expr as a write.
1361 * If a scalar is being accessed, then mark its value
1362 * as unknown in assigned_value.
1364 void PetScan::mark_write(struct pet_expr
*access
)
1369 access
->acc
.write
= 1;
1370 access
->acc
.read
= 0;
1372 if (isl_map_dim(access
->acc
.access
, isl_dim_out
) != 0)
1375 id
= isl_map_get_tuple_id(access
->acc
.access
, isl_dim_out
);
1376 decl
= (ValueDecl
*) isl_id_get_user(id
);
1377 clear_assignment(assigned_value
, decl
);
1381 /* Construct a pet_expr representing a binary operator expression.
1383 * If the top level operator is an assignment and the LHS is an access,
1384 * then we mark that access as a write. If the operator is a compound
1385 * assignment, the access is marked as both a read and a write.
1387 * If "expr" assigns something to a scalar variable, then we mark
1388 * the variable as having been assigned. If, furthermore, the expression
1389 * is affine, then keep track of this value in assigned_value
1390 * so that we can plug it in when we later come across the same variable.
1392 struct pet_expr
*PetScan::extract_expr(BinaryOperator
*expr
)
1394 struct pet_expr
*lhs
, *rhs
;
1395 enum pet_op_type op
;
1397 op
= BinaryOperatorKind2pet_op_type(expr
->getOpcode());
1398 if (op
== pet_op_last
) {
1403 lhs
= extract_expr(expr
->getLHS());
1404 rhs
= extract_expr(expr
->getRHS());
1406 if (expr
->isAssignmentOp() && lhs
&& lhs
->type
== pet_expr_access
) {
1408 if (expr
->isCompoundAssignmentOp())
1412 if (expr
->getOpcode() == BO_Assign
&&
1413 lhs
&& lhs
->type
== pet_expr_access
&&
1414 isl_map_dim(lhs
->acc
.access
, isl_dim_out
) == 0) {
1415 isl_id
*id
= isl_map_get_tuple_id(lhs
->acc
.access
, isl_dim_out
);
1416 ValueDecl
*decl
= (ValueDecl
*) isl_id_get_user(id
);
1417 Expr
*rhs
= expr
->getRHS();
1418 isl_pw_aff
*pa
= try_extract_affine(rhs
);
1419 clear_assignment(assigned_value
, decl
);
1421 assigned_value
[decl
] = pa
;
1422 insert_expression(pa
);
1427 return pet_expr_new_binary(ctx
, op
, lhs
, rhs
);
1430 /* Construct a pet_expr representing a conditional operation.
1432 * We first try to extract the condition as an affine expression.
1433 * If that fails, we construct a pet_expr tree representing the condition.
1435 struct pet_expr
*PetScan::extract_expr(ConditionalOperator
*expr
)
1437 struct pet_expr
*cond
, *lhs
, *rhs
;
1440 pa
= try_extract_affine(expr
->getCond());
1442 isl_set
*test
= isl_set_from_pw_aff(pa
);
1443 cond
= pet_expr_from_access(isl_map_from_range(test
));
1445 cond
= extract_expr(expr
->getCond());
1446 lhs
= extract_expr(expr
->getTrueExpr());
1447 rhs
= extract_expr(expr
->getFalseExpr());
1449 return pet_expr_new_ternary(ctx
, cond
, lhs
, rhs
);
1452 struct pet_expr
*PetScan::extract_expr(ImplicitCastExpr
*expr
)
1454 return extract_expr(expr
->getSubExpr());
1457 /* Construct a pet_expr representing a floating point value.
1459 struct pet_expr
*PetScan::extract_expr(FloatingLiteral
*expr
)
1461 return pet_expr_new_double(ctx
, expr
->getValueAsApproximateDouble());
1464 /* Extract an access relation from "expr" and then convert it into
1467 struct pet_expr
*PetScan::extract_access_expr(Expr
*expr
)
1470 struct pet_expr
*pe
;
1472 access
= extract_access(expr
);
1474 pe
= pet_expr_from_access(access
);
1479 struct pet_expr
*PetScan::extract_expr(ParenExpr
*expr
)
1481 return extract_expr(expr
->getSubExpr());
1484 /* Construct a pet_expr representing a function call.
1486 * If we are passing along a pointer to an array element
1487 * or an entire row or even higher dimensional slice of an array,
1488 * then the function being called may write into the array.
1490 * We assume here that if the function is declared to take a pointer
1491 * to a const type, then the function will perform a read
1492 * and that otherwise, it will perform a write.
1494 struct pet_expr
*PetScan::extract_expr(CallExpr
*expr
)
1496 struct pet_expr
*res
= NULL
;
1500 fd
= expr
->getDirectCallee();
1506 name
= fd
->getDeclName().getAsString();
1507 res
= pet_expr_new_call(ctx
, name
.c_str(), expr
->getNumArgs());
1511 for (int i
= 0; i
< expr
->getNumArgs(); ++i
) {
1512 Expr
*arg
= expr
->getArg(i
);
1516 if (arg
->getStmtClass() == Stmt::ImplicitCastExprClass
) {
1517 ImplicitCastExpr
*ice
= cast
<ImplicitCastExpr
>(arg
);
1518 arg
= ice
->getSubExpr();
1520 if (arg
->getStmtClass() == Stmt::UnaryOperatorClass
) {
1521 UnaryOperator
*op
= cast
<UnaryOperator
>(arg
);
1522 if (op
->getOpcode() == UO_AddrOf
) {
1524 arg
= op
->getSubExpr();
1527 res
->args
[i
] = PetScan::extract_expr(arg
);
1528 main_arg
= res
->args
[i
];
1530 res
->args
[i
] = pet_expr_new_unary(ctx
,
1531 pet_op_address_of
, res
->args
[i
]);
1534 if (arg
->getStmtClass() == Stmt::ArraySubscriptExprClass
&&
1535 array_depth(arg
->getType().getTypePtr()) > 0)
1537 if (is_addr
&& main_arg
->type
== pet_expr_access
) {
1539 if (!fd
->hasPrototype()) {
1540 unsupported(expr
, "prototype required");
1543 parm
= fd
->getParamDecl(i
);
1544 if (!const_base(parm
->getType()))
1545 mark_write(main_arg
);
1555 /* Try and onstruct a pet_expr representing "expr".
1557 struct pet_expr
*PetScan::extract_expr(Expr
*expr
)
1559 switch (expr
->getStmtClass()) {
1560 case Stmt::UnaryOperatorClass
:
1561 return extract_expr(cast
<UnaryOperator
>(expr
));
1562 case Stmt::CompoundAssignOperatorClass
:
1563 case Stmt::BinaryOperatorClass
:
1564 return extract_expr(cast
<BinaryOperator
>(expr
));
1565 case Stmt::ImplicitCastExprClass
:
1566 return extract_expr(cast
<ImplicitCastExpr
>(expr
));
1567 case Stmt::ArraySubscriptExprClass
:
1568 case Stmt::DeclRefExprClass
:
1569 case Stmt::IntegerLiteralClass
:
1570 return extract_access_expr(expr
);
1571 case Stmt::FloatingLiteralClass
:
1572 return extract_expr(cast
<FloatingLiteral
>(expr
));
1573 case Stmt::ParenExprClass
:
1574 return extract_expr(cast
<ParenExpr
>(expr
));
1575 case Stmt::ConditionalOperatorClass
:
1576 return extract_expr(cast
<ConditionalOperator
>(expr
));
1577 case Stmt::CallExprClass
:
1578 return extract_expr(cast
<CallExpr
>(expr
));
1585 /* Check if the given initialization statement is an assignment.
1586 * If so, return that assignment. Otherwise return NULL.
1588 BinaryOperator
*PetScan::initialization_assignment(Stmt
*init
)
1590 BinaryOperator
*ass
;
1592 if (init
->getStmtClass() != Stmt::BinaryOperatorClass
)
1595 ass
= cast
<BinaryOperator
>(init
);
1596 if (ass
->getOpcode() != BO_Assign
)
1602 /* Check if the given initialization statement is a declaration
1603 * of a single variable.
1604 * If so, return that declaration. Otherwise return NULL.
1606 Decl
*PetScan::initialization_declaration(Stmt
*init
)
1610 if (init
->getStmtClass() != Stmt::DeclStmtClass
)
1613 decl
= cast
<DeclStmt
>(init
);
1615 if (!decl
->isSingleDecl())
1618 return decl
->getSingleDecl();
1621 /* Given the assignment operator in the initialization of a for loop,
1622 * extract the induction variable, i.e., the (integer)variable being
1625 ValueDecl
*PetScan::extract_induction_variable(BinaryOperator
*init
)
1632 lhs
= init
->getLHS();
1633 if (lhs
->getStmtClass() != Stmt::DeclRefExprClass
) {
1638 ref
= cast
<DeclRefExpr
>(lhs
);
1639 decl
= ref
->getDecl();
1640 type
= decl
->getType().getTypePtr();
1642 if (!type
->isIntegerType()) {
1650 /* Given the initialization statement of a for loop and the single
1651 * declaration in this initialization statement,
1652 * extract the induction variable, i.e., the (integer) variable being
1655 VarDecl
*PetScan::extract_induction_variable(Stmt
*init
, Decl
*decl
)
1659 vd
= cast
<VarDecl
>(decl
);
1661 const QualType type
= vd
->getType();
1662 if (!type
->isIntegerType()) {
1667 if (!vd
->getInit()) {
1675 /* Check that op is of the form iv++ or iv--.
1676 * Return an affine expression "1" or "-1" accordingly.
1678 __isl_give isl_pw_aff
*PetScan::extract_unary_increment(
1679 clang::UnaryOperator
*op
, clang::ValueDecl
*iv
)
1686 if (!op
->isIncrementDecrementOp()) {
1691 sub
= op
->getSubExpr();
1692 if (sub
->getStmtClass() != Stmt::DeclRefExprClass
) {
1697 ref
= cast
<DeclRefExpr
>(sub
);
1698 if (ref
->getDecl() != iv
) {
1703 space
= isl_space_params_alloc(ctx
, 0);
1704 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(space
));
1706 if (op
->isIncrementOp())
1707 aff
= isl_aff_add_constant_si(aff
, 1);
1709 aff
= isl_aff_add_constant_si(aff
, -1);
1711 return isl_pw_aff_from_aff(aff
);
1714 /* If the isl_pw_aff on which isl_pw_aff_foreach_piece is called
1715 * has a single constant expression, then put this constant in *user.
1716 * The caller is assumed to have checked that this function will
1717 * be called exactly once.
1719 static int extract_cst(__isl_take isl_set
*set
, __isl_take isl_aff
*aff
,
1722 isl_int
*inc
= (isl_int
*)user
;
1725 if (isl_aff_is_cst(aff
))
1726 isl_aff_get_constant(aff
, inc
);
1736 /* Check if op is of the form
1740 * and return inc as an affine expression.
1742 * We extract an affine expression from the RHS, subtract iv and return
1745 __isl_give isl_pw_aff
*PetScan::extract_binary_increment(BinaryOperator
*op
,
1746 clang::ValueDecl
*iv
)
1755 if (op
->getOpcode() != BO_Assign
) {
1761 if (lhs
->getStmtClass() != Stmt::DeclRefExprClass
) {
1766 ref
= cast
<DeclRefExpr
>(lhs
);
1767 if (ref
->getDecl() != iv
) {
1772 val
= extract_affine(op
->getRHS());
1774 id
= isl_id_alloc(ctx
, iv
->getName().str().c_str(), iv
);
1776 dim
= isl_space_params_alloc(ctx
, 1);
1777 dim
= isl_space_set_dim_id(dim
, isl_dim_param
, 0, id
);
1778 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(dim
));
1779 aff
= isl_aff_add_coefficient_si(aff
, isl_dim_param
, 0, 1);
1781 val
= isl_pw_aff_sub(val
, isl_pw_aff_from_aff(aff
));
1786 /* Check that op is of the form iv += cst or iv -= cst
1787 * and return an affine expression corresponding oto cst or -cst accordingly.
1789 __isl_give isl_pw_aff
*PetScan::extract_compound_increment(
1790 CompoundAssignOperator
*op
, clang::ValueDecl
*iv
)
1796 BinaryOperatorKind opcode
;
1798 opcode
= op
->getOpcode();
1799 if (opcode
!= BO_AddAssign
&& opcode
!= BO_SubAssign
) {
1803 if (opcode
== BO_SubAssign
)
1807 if (lhs
->getStmtClass() != Stmt::DeclRefExprClass
) {
1812 ref
= cast
<DeclRefExpr
>(lhs
);
1813 if (ref
->getDecl() != iv
) {
1818 val
= extract_affine(op
->getRHS());
1820 val
= isl_pw_aff_neg(val
);
1825 /* Check that the increment of the given for loop increments
1826 * (or decrements) the induction variable "iv" and return
1827 * the increment as an affine expression if successful.
1829 __isl_give isl_pw_aff
*PetScan::extract_increment(clang::ForStmt
*stmt
,
1832 Stmt
*inc
= stmt
->getInc();
1839 if (inc
->getStmtClass() == Stmt::UnaryOperatorClass
)
1840 return extract_unary_increment(cast
<UnaryOperator
>(inc
), iv
);
1841 if (inc
->getStmtClass() == Stmt::CompoundAssignOperatorClass
)
1842 return extract_compound_increment(
1843 cast
<CompoundAssignOperator
>(inc
), iv
);
1844 if (inc
->getStmtClass() == Stmt::BinaryOperatorClass
)
1845 return extract_binary_increment(cast
<BinaryOperator
>(inc
), iv
);
1851 /* Embed the given iteration domain in an extra outer loop
1852 * with induction variable "var".
1853 * If this variable appeared as a parameter in the constraints,
1854 * it is replaced by the new outermost dimension.
1856 static __isl_give isl_set
*embed(__isl_take isl_set
*set
,
1857 __isl_take isl_id
*var
)
1861 set
= isl_set_insert_dims(set
, isl_dim_set
, 0, 1);
1862 pos
= isl_set_find_dim_by_id(set
, isl_dim_param
, var
);
1864 set
= isl_set_equate(set
, isl_dim_param
, pos
, isl_dim_set
, 0);
1865 set
= isl_set_project_out(set
, isl_dim_param
, pos
, 1);
1872 /* Return those elements in the space of "cond" that come after
1873 * (based on "sign") an element in "cond".
1875 static __isl_give isl_set
*after(__isl_take isl_set
*cond
, int sign
)
1877 isl_map
*previous_to_this
;
1880 previous_to_this
= isl_map_lex_lt(isl_set_get_space(cond
));
1882 previous_to_this
= isl_map_lex_gt(isl_set_get_space(cond
));
1884 cond
= isl_set_apply(cond
, previous_to_this
);
1889 /* Create the infinite iteration domain
1891 * { [id] : id >= 0 }
1893 * If "scop" has an affine skip of type pet_skip_later,
1894 * then remove those iterations i that have an earlier iteration
1895 * where the skip condition is satisfied, meaning that iteration i
1897 * Since we are dealing with a loop without loop iterator,
1898 * the skip condition cannot refer to the current loop iterator and
1899 * so effectively, the returned set is of the form
1901 * { [0]; [id] : id >= 1 and not skip }
1903 static __isl_give isl_set
*infinite_domain(__isl_take isl_id
*id
,
1904 struct pet_scop
*scop
)
1906 isl_ctx
*ctx
= isl_id_get_ctx(id
);
1910 domain
= isl_set_nat_universe(isl_space_set_alloc(ctx
, 0, 1));
1911 domain
= isl_set_set_dim_id(domain
, isl_dim_set
, 0, id
);
1913 if (!pet_scop_has_affine_skip(scop
, pet_skip_later
))
1916 skip
= pet_scop_get_skip(scop
, pet_skip_later
);
1917 skip
= isl_set_fix_si(skip
, isl_dim_set
, 0, 1);
1918 skip
= isl_set_params(skip
);
1919 skip
= embed(skip
, isl_id_copy(id
));
1920 skip
= isl_set_intersect(skip
, isl_set_copy(domain
));
1921 domain
= isl_set_subtract(domain
, after(skip
, 1));
1926 /* Create an identity mapping on the space containing "domain".
1928 static __isl_give isl_map
*identity_map(__isl_keep isl_set
*domain
)
1933 space
= isl_space_map_from_set(isl_set_get_space(domain
));
1934 id
= isl_map_identity(space
);
1939 /* Add a filter to "scop" that imposes that it is only executed
1940 * when "break_access" has a zero value for all previous iterations
1943 * The input "break_access" has a zero-dimensional domain and range.
1945 static struct pet_scop
*scop_add_break(struct pet_scop
*scop
,
1946 __isl_take isl_map
*break_access
, __isl_take isl_set
*domain
, int sign
)
1948 isl_ctx
*ctx
= isl_set_get_ctx(domain
);
1952 id_test
= isl_map_get_tuple_id(break_access
, isl_dim_out
);
1953 break_access
= isl_map_add_dims(break_access
, isl_dim_in
, 1);
1954 break_access
= isl_map_add_dims(break_access
, isl_dim_out
, 1);
1955 break_access
= isl_map_intersect_range(break_access
, domain
);
1956 break_access
= isl_map_set_tuple_id(break_access
, isl_dim_out
, id_test
);
1958 prev
= isl_map_lex_gt_first(isl_map_get_space(break_access
), 1);
1960 prev
= isl_map_lex_lt_first(isl_map_get_space(break_access
), 1);
1961 break_access
= isl_map_intersect(break_access
, prev
);
1962 scop
= pet_scop_filter(scop
, break_access
, 0);
1963 scop
= pet_scop_merge_filters(scop
);
1968 /* Construct a pet_scop for an infinite loop around the given body.
1970 * We extract a pet_scop for the body and then embed it in a loop with
1979 * If the body contains any break, then it is taken into
1980 * account in infinite_domain (if the skip condition is affine)
1981 * or in scop_add_break (if the skip condition is not affine).
1983 struct pet_scop
*PetScan::extract_infinite_loop(Stmt
*body
)
1989 struct pet_scop
*scop
;
1992 scop
= extract(body
);
1996 id
= isl_id_alloc(ctx
, "t", NULL
);
1997 domain
= infinite_domain(isl_id_copy(id
), scop
);
1998 ident
= identity_map(domain
);
2000 has_var_break
= pet_scop_has_var_skip(scop
, pet_skip_later
);
2002 access
= pet_scop_get_skip_map(scop
, pet_skip_later
);
2004 scop
= pet_scop_embed(scop
, isl_set_copy(domain
),
2005 isl_map_copy(ident
), ident
, id
);
2007 scop
= scop_add_break(scop
, access
, domain
, 1);
2009 isl_set_free(domain
);
2014 /* Construct a pet_scop for an infinite loop, i.e., a loop of the form
2020 struct pet_scop
*PetScan::extract_infinite_for(ForStmt
*stmt
)
2022 return extract_infinite_loop(stmt
->getBody());
2025 /* Create an access to a virtual array representing the result
2027 * Unlike other accessed data, the id of the array is NULL as
2028 * there is no ValueDecl in the program corresponding to the virtual
2030 * The array starts out as a scalar, but grows along with the
2031 * statement writing to the array in pet_scop_embed.
2033 static __isl_give isl_map
*create_test_access(isl_ctx
*ctx
, int test_nr
)
2035 isl_space
*dim
= isl_space_alloc(ctx
, 0, 0, 0);
2039 snprintf(name
, sizeof(name
), "__pet_test_%d", test_nr
);
2040 id
= isl_id_alloc(ctx
, name
, NULL
);
2041 dim
= isl_space_set_tuple_id(dim
, isl_dim_out
, id
);
2042 return isl_map_universe(dim
);
2045 /* Add an array with the given extent ("access") to the list
2046 * of arrays in "scop" and return the extended pet_scop.
2047 * The array is marked as attaining values 0 and 1 only and
2048 * as each element being assigned at most once.
2050 static struct pet_scop
*scop_add_array(struct pet_scop
*scop
,
2051 __isl_keep isl_map
*access
, clang::ASTContext
&ast_ctx
)
2053 isl_ctx
*ctx
= isl_map_get_ctx(access
);
2055 struct pet_array
**arrays
;
2056 struct pet_array
*array
;
2063 arrays
= isl_realloc_array(ctx
, scop
->arrays
, struct pet_array
*,
2067 scop
->arrays
= arrays
;
2069 array
= isl_calloc_type(ctx
, struct pet_array
);
2073 array
->extent
= isl_map_range(isl_map_copy(access
));
2074 dim
= isl_space_params_alloc(ctx
, 0);
2075 array
->context
= isl_set_universe(dim
);
2076 dim
= isl_space_set_alloc(ctx
, 0, 1);
2077 array
->value_bounds
= isl_set_universe(dim
);
2078 array
->value_bounds
= isl_set_lower_bound_si(array
->value_bounds
,
2080 array
->value_bounds
= isl_set_upper_bound_si(array
->value_bounds
,
2082 array
->element_type
= strdup("int");
2083 array
->element_size
= ast_ctx
.getTypeInfo(ast_ctx
.IntTy
).first
/ 8;
2084 array
->uniquely_defined
= 1;
2086 scop
->arrays
[scop
->n_array
] = array
;
2089 if (!array
->extent
|| !array
->context
)
2094 pet_scop_free(scop
);
2098 /* Construct a pet_scop for a while loop of the form
2103 * In particular, construct a scop for an infinite loop around body and
2104 * intersect the domain with the affine expression.
2105 * Note that this intersection may result in an empty loop.
2107 struct pet_scop
*PetScan::extract_affine_while(__isl_take isl_pw_aff
*pa
,
2110 struct pet_scop
*scop
;
2114 valid
= isl_pw_aff_domain(isl_pw_aff_copy(pa
));
2115 dom
= isl_pw_aff_non_zero_set(pa
);
2116 scop
= extract_infinite_loop(body
);
2117 scop
= pet_scop_restrict(scop
, dom
);
2118 scop
= pet_scop_restrict_context(scop
, valid
);
2123 /* Construct a scop for a while, given the scops for the condition
2124 * and the body, the filter access and the iteration domain of
2127 * In particular, the scop for the condition is filtered to depend
2128 * on "test_access" evaluating to true for all previous iterations
2129 * of the loop, while the scop for the body is filtered to depend
2130 * on "test_access" evaluating to true for all iterations up to the
2131 * current iteration.
2133 * These filtered scops are then combined into a single scop.
2135 * "sign" is positive if the iterator increases and negative
2138 static struct pet_scop
*scop_add_while(struct pet_scop
*scop_cond
,
2139 struct pet_scop
*scop_body
, __isl_take isl_map
*test_access
,
2140 __isl_take isl_set
*domain
, int sign
)
2142 isl_ctx
*ctx
= isl_set_get_ctx(domain
);
2146 id_test
= isl_map_get_tuple_id(test_access
, isl_dim_out
);
2147 test_access
= isl_map_add_dims(test_access
, isl_dim_in
, 1);
2148 test_access
= isl_map_add_dims(test_access
, isl_dim_out
, 1);
2149 test_access
= isl_map_intersect_range(test_access
, domain
);
2150 test_access
= isl_map_set_tuple_id(test_access
, isl_dim_out
, id_test
);
2152 prev
= isl_map_lex_ge_first(isl_map_get_space(test_access
), 1);
2154 prev
= isl_map_lex_le_first(isl_map_get_space(test_access
), 1);
2155 test_access
= isl_map_intersect(test_access
, prev
);
2156 scop_body
= pet_scop_filter(scop_body
, isl_map_copy(test_access
), 1);
2158 prev
= isl_map_lex_gt_first(isl_map_get_space(test_access
), 1);
2160 prev
= isl_map_lex_lt_first(isl_map_get_space(test_access
), 1);
2161 test_access
= isl_map_intersect(test_access
, prev
);
2162 scop_cond
= pet_scop_filter(scop_cond
, test_access
, 1);
2164 return pet_scop_add_seq(ctx
, scop_cond
, scop_body
);
2167 /* Check if the while loop is of the form
2169 * while (affine expression)
2172 * If so, call extract_affine_while to construct a scop.
2174 * Otherwise, construct a generic while scop, with iteration domain
2175 * { [t] : t >= 0 }. The scop consists of two parts, one for
2176 * evaluating the condition and one for the body.
2177 * The schedule is adjusted to reflect that the condition is evaluated
2178 * before the body is executed and the body is filtered to depend
2179 * on the result of the condition evaluating to true on all iterations
2180 * up to the current iteration, while the evaluation the condition itself
2181 * is filtered to depend on the result of the condition evaluating to true
2182 * on all previous iterations.
2183 * The context of the scop representing the body is dropped
2184 * because we don't know how many times the body will be executed,
2187 * If the body contains any break, then it is taken into
2188 * account in infinite_domain (if the skip condition is affine)
2189 * or in scop_add_break (if the skip condition is not affine).
2191 struct pet_scop
*PetScan::extract(WhileStmt
*stmt
)
2195 isl_map
*test_access
;
2199 struct pet_scop
*scop
, *scop_body
;
2201 isl_map
*break_access
;
2203 cond
= stmt
->getCond();
2209 clear_assignments
clear(assigned_value
);
2210 clear
.TraverseStmt(stmt
->getBody());
2212 pa
= try_extract_affine_condition(cond
);
2214 return extract_affine_while(pa
, stmt
->getBody());
2216 if (!allow_nested
) {
2221 test_access
= create_test_access(ctx
, n_test
++);
2222 scop
= extract_non_affine_condition(cond
, isl_map_copy(test_access
));
2223 scop
= scop_add_array(scop
, test_access
, ast_context
);
2224 scop_body
= extract(stmt
->getBody());
2226 id
= isl_id_alloc(ctx
, "t", NULL
);
2227 domain
= infinite_domain(isl_id_copy(id
), scop_body
);
2228 ident
= identity_map(domain
);
2230 has_var_break
= pet_scop_has_var_skip(scop_body
, pet_skip_later
);
2232 break_access
= pet_scop_get_skip_map(scop_body
, pet_skip_later
);
2234 scop
= pet_scop_prefix(scop
, 0);
2235 scop
= pet_scop_embed(scop
, isl_set_copy(domain
), isl_map_copy(ident
),
2236 isl_map_copy(ident
), isl_id_copy(id
));
2237 scop_body
= pet_scop_reset_context(scop_body
);
2238 scop_body
= pet_scop_prefix(scop_body
, 1);
2239 scop_body
= pet_scop_embed(scop_body
, isl_set_copy(domain
),
2240 isl_map_copy(ident
), ident
, id
);
2242 if (has_var_break
) {
2243 scop
= scop_add_break(scop
, isl_map_copy(break_access
),
2244 isl_set_copy(domain
), 1);
2245 scop_body
= scop_add_break(scop_body
, break_access
,
2246 isl_set_copy(domain
), 1);
2248 scop
= scop_add_while(scop
, scop_body
, test_access
, domain
, 1);
2253 /* Check whether "cond" expresses a simple loop bound
2254 * on the only set dimension.
2255 * In particular, if "up" is set then "cond" should contain only
2256 * upper bounds on the set dimension.
2257 * Otherwise, it should contain only lower bounds.
2259 static bool is_simple_bound(__isl_keep isl_set
*cond
, isl_int inc
)
2261 if (isl_int_is_pos(inc
))
2262 return !isl_set_dim_has_any_lower_bound(cond
, isl_dim_set
, 0);
2264 return !isl_set_dim_has_any_upper_bound(cond
, isl_dim_set
, 0);
2267 /* Extend a condition on a given iteration of a loop to one that
2268 * imposes the same condition on all previous iterations.
2269 * "domain" expresses the lower [upper] bound on the iterations
2270 * when inc is positive [negative].
2272 * In particular, we construct the condition (when inc is positive)
2274 * forall i' : (domain(i') and i' <= i) => cond(i')
2276 * which is equivalent to
2278 * not exists i' : domain(i') and i' <= i and not cond(i')
2280 * We construct this set by negating cond, applying a map
2282 * { [i'] -> [i] : domain(i') and i' <= i }
2284 * and then negating the result again.
2286 static __isl_give isl_set
*valid_for_each_iteration(__isl_take isl_set
*cond
,
2287 __isl_take isl_set
*domain
, isl_int inc
)
2289 isl_map
*previous_to_this
;
2291 if (isl_int_is_pos(inc
))
2292 previous_to_this
= isl_map_lex_le(isl_set_get_space(domain
));
2294 previous_to_this
= isl_map_lex_ge(isl_set_get_space(domain
));
2296 previous_to_this
= isl_map_intersect_domain(previous_to_this
, domain
);
2298 cond
= isl_set_complement(cond
);
2299 cond
= isl_set_apply(cond
, previous_to_this
);
2300 cond
= isl_set_complement(cond
);
2305 /* Construct a domain of the form
2307 * [id] -> { : exists a: id = init + a * inc and a >= 0 }
2309 static __isl_give isl_set
*strided_domain(__isl_take isl_id
*id
,
2310 __isl_take isl_pw_aff
*init
, isl_int inc
)
2316 init
= isl_pw_aff_insert_dims(init
, isl_dim_in
, 0, 1);
2317 dim
= isl_pw_aff_get_domain_space(init
);
2318 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(dim
));
2319 aff
= isl_aff_add_coefficient(aff
, isl_dim_in
, 0, inc
);
2320 init
= isl_pw_aff_add(init
, isl_pw_aff_from_aff(aff
));
2322 dim
= isl_space_set_alloc(isl_pw_aff_get_ctx(init
), 1, 1);
2323 dim
= isl_space_set_dim_id(dim
, isl_dim_param
, 0, id
);
2324 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(dim
));
2325 aff
= isl_aff_add_coefficient_si(aff
, isl_dim_param
, 0, 1);
2327 set
= isl_pw_aff_eq_set(isl_pw_aff_from_aff(aff
), init
);
2329 set
= isl_set_lower_bound_si(set
, isl_dim_set
, 0, 0);
2331 return isl_set_params(set
);
2334 /* Assuming "cond" represents a bound on a loop where the loop
2335 * iterator "iv" is incremented (or decremented) by one, check if wrapping
2338 * Under the given assumptions, wrapping is only possible if "cond" allows
2339 * for the last value before wrapping, i.e., 2^width - 1 in case of an
2340 * increasing iterator and 0 in case of a decreasing iterator.
2342 static bool can_wrap(__isl_keep isl_set
*cond
, ValueDecl
*iv
, isl_int inc
)
2348 test
= isl_set_copy(cond
);
2350 isl_int_init(limit
);
2351 if (isl_int_is_neg(inc
))
2352 isl_int_set_si(limit
, 0);
2354 isl_int_set_si(limit
, 1);
2355 isl_int_mul_2exp(limit
, limit
, get_type_size(iv
));
2356 isl_int_sub_ui(limit
, limit
, 1);
2359 test
= isl_set_fix(cond
, isl_dim_set
, 0, limit
);
2360 cw
= !isl_set_is_empty(test
);
2363 isl_int_clear(limit
);
2368 /* Given a one-dimensional space, construct the following mapping on this
2371 * { [v] -> [v mod 2^width] }
2373 * where width is the number of bits used to represent the values
2374 * of the unsigned variable "iv".
2376 static __isl_give isl_map
*compute_wrapping(__isl_take isl_space
*dim
,
2384 isl_int_set_si(mod
, 1);
2385 isl_int_mul_2exp(mod
, mod
, get_type_size(iv
));
2387 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(dim
));
2388 aff
= isl_aff_add_coefficient_si(aff
, isl_dim_in
, 0, 1);
2389 aff
= isl_aff_mod(aff
, mod
);
2393 return isl_map_from_basic_map(isl_basic_map_from_aff(aff
));
2394 map
= isl_map_reverse(map
);
2397 /* Project out the parameter "id" from "set".
2399 static __isl_give isl_set
*set_project_out_by_id(__isl_take isl_set
*set
,
2400 __isl_keep isl_id
*id
)
2404 pos
= isl_set_find_dim_by_id(set
, isl_dim_param
, id
);
2406 set
= isl_set_project_out(set
, isl_dim_param
, pos
, 1);
2411 /* Compute the set of parameters for which "set1" is a subset of "set2".
2413 * set1 is a subset of set2 if
2415 * forall i in set1 : i in set2
2419 * not exists i in set1 and i not in set2
2423 * not exists i in set1 \ set2
2425 static __isl_give isl_set
*enforce_subset(__isl_take isl_set
*set1
,
2426 __isl_take isl_set
*set2
)
2428 return isl_set_complement(isl_set_params(isl_set_subtract(set1
, set2
)));
2431 /* Compute the set of parameter values for which "cond" holds
2432 * on the next iteration for each element of "dom".
2434 * We first construct mapping { [i] -> [i + inc] }, apply that to "dom"
2435 * and then compute the set of parameters for which the result is a subset
2438 static __isl_give isl_set
*valid_on_next(__isl_take isl_set
*cond
,
2439 __isl_take isl_set
*dom
, isl_int inc
)
2445 space
= isl_set_get_space(dom
);
2446 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(space
));
2447 aff
= isl_aff_add_coefficient_si(aff
, isl_dim_in
, 0, 1);
2448 aff
= isl_aff_add_constant(aff
, inc
);
2449 next
= isl_map_from_basic_map(isl_basic_map_from_aff(aff
));
2451 dom
= isl_set_apply(dom
, next
);
2453 return enforce_subset(dom
, cond
);
2456 /* Does "id" refer to a nested access?
2458 static bool is_nested_parameter(__isl_keep isl_id
*id
)
2460 return id
&& isl_id_get_user(id
) && !isl_id_get_name(id
);
2463 /* Does parameter "pos" of "space" refer to a nested access?
2465 static bool is_nested_parameter(__isl_keep isl_space
*space
, int pos
)
2470 id
= isl_space_get_dim_id(space
, isl_dim_param
, pos
);
2471 nested
= is_nested_parameter(id
);
2477 /* Does "space" involve any parameters that refer to nested
2478 * accesses, i.e., parameters with no name?
2480 static bool has_nested(__isl_keep isl_space
*space
)
2484 nparam
= isl_space_dim(space
, isl_dim_param
);
2485 for (int i
= 0; i
< nparam
; ++i
)
2486 if (is_nested_parameter(space
, i
))
2492 /* Does "pa" involve any parameters that refer to nested
2493 * accesses, i.e., parameters with no name?
2495 static bool has_nested(__isl_keep isl_pw_aff
*pa
)
2500 space
= isl_pw_aff_get_space(pa
);
2501 nested
= has_nested(space
);
2502 isl_space_free(space
);
2507 /* Construct a pet_scop for a for statement.
2508 * The for loop is required to be of the form
2510 * for (i = init; condition; ++i)
2514 * for (i = init; condition; --i)
2516 * The initialization of the for loop should either be an assignment
2517 * to an integer variable, or a declaration of such a variable with
2520 * The condition is allowed to contain nested accesses, provided
2521 * they are not being written to inside the body of the loop.
2522 * Otherwise, or if the condition is otherwise non-affine, the for loop is
2523 * essentially treated as a while loop, with iteration domain
2524 * { [i] : i >= init }.
2526 * We extract a pet_scop for the body and then embed it in a loop with
2527 * iteration domain and schedule
2529 * { [i] : i >= init and condition' }
2534 * { [i] : i <= init and condition' }
2537 * Where condition' is equal to condition if the latter is
2538 * a simple upper [lower] bound and a condition that is extended
2539 * to apply to all previous iterations otherwise.
2541 * If the condition is non-affine, then we drop the condition from the
2542 * iteration domain and instead create a separate statement
2543 * for evaluating the condition. The body is then filtered to depend
2544 * on the result of the condition evaluating to true on all iterations
2545 * up to the current iteration, while the evaluation the condition itself
2546 * is filtered to depend on the result of the condition evaluating to true
2547 * on all previous iterations.
2548 * The context of the scop representing the body is dropped
2549 * because we don't know how many times the body will be executed,
2552 * If the stride of the loop is not 1, then "i >= init" is replaced by
2554 * (exists a: i = init + stride * a and a >= 0)
2556 * If the loop iterator i is unsigned, then wrapping may occur.
2557 * During the computation, we work with a virtual iterator that
2558 * does not wrap. However, the condition in the code applies
2559 * to the wrapped value, so we need to change condition(i)
2560 * into condition([i % 2^width]).
2561 * After computing the virtual domain and schedule, we apply
2562 * the function { [v] -> [v % 2^width] } to the domain and the domain
2563 * of the schedule. In order not to lose any information, we also
2564 * need to intersect the domain of the schedule with the virtual domain
2565 * first, since some iterations in the wrapped domain may be scheduled
2566 * several times, typically an infinite number of times.
2567 * Note that there may be no need to perform this final wrapping
2568 * if the loop condition (after wrapping) satisfies certain conditions.
2569 * However, the is_simple_bound condition is not enough since it doesn't
2570 * check if there even is an upper bound.
2572 * If the loop condition is non-affine, then we keep the virtual
2573 * iterator in the iteration domain and instead replace all accesses
2574 * to the original iterator by the wrapping of the virtual iterator.
2576 * Wrapping on unsigned iterators can be avoided entirely if
2577 * loop condition is simple, the loop iterator is incremented
2578 * [decremented] by one and the last value before wrapping cannot
2579 * possibly satisfy the loop condition.
2581 * Before extracting a pet_scop from the body we remove all
2582 * assignments in assigned_value to variables that are assigned
2583 * somewhere in the body of the loop.
2585 * Valid parameters for a for loop are those for which the initial
2586 * value itself, the increment on each domain iteration and
2587 * the condition on both the initial value and
2588 * the result of incrementing the iterator for each iteration of the domain
2590 * If the loop condition is non-affine, then we only consider validity
2591 * of the initial value.
2593 * If the body contains any break, then we keep track of it in "skip"
2594 * (if the skip condition is affine) or it is handled in scop_add_break
2595 * (if the skip condition is not affine).
2596 * Note that the affine break condition needs to be considered with
2597 * respect to previous iterations in the virtual domain (if any)
2598 * and that the domain needs to be kept virtual if there is a non-affine
2601 struct pet_scop
*PetScan::extract_for(ForStmt
*stmt
)
2603 BinaryOperator
*ass
;
2611 isl_set
*cond
= NULL
;
2612 isl_set
*skip
= NULL
;
2614 struct pet_scop
*scop
, *scop_cond
= NULL
;
2615 assigned_value_cache
cache(assigned_value
);
2621 bool keep_virtual
= false;
2622 bool has_affine_break
;
2624 isl_map
*wrap
= NULL
;
2625 isl_pw_aff
*pa
, *pa_inc
, *init_val
;
2626 isl_set
*valid_init
;
2627 isl_set
*valid_cond
;
2628 isl_set
*valid_cond_init
;
2629 isl_set
*valid_cond_next
;
2631 isl_map
*test_access
= NULL
, *break_access
= NULL
;
2634 if (!stmt
->getInit() && !stmt
->getCond() && !stmt
->getInc())
2635 return extract_infinite_for(stmt
);
2637 init
= stmt
->getInit();
2642 if ((ass
= initialization_assignment(init
)) != NULL
) {
2643 iv
= extract_induction_variable(ass
);
2646 lhs
= ass
->getLHS();
2647 rhs
= ass
->getRHS();
2648 } else if ((decl
= initialization_declaration(init
)) != NULL
) {
2649 VarDecl
*var
= extract_induction_variable(init
, decl
);
2653 rhs
= var
->getInit();
2654 lhs
= create_DeclRefExpr(var
);
2656 unsupported(stmt
->getInit());
2660 pa_inc
= extract_increment(stmt
, iv
);
2665 if (isl_pw_aff_n_piece(pa_inc
) != 1 ||
2666 isl_pw_aff_foreach_piece(pa_inc
, &extract_cst
, &inc
) < 0) {
2667 isl_pw_aff_free(pa_inc
);
2668 unsupported(stmt
->getInc());
2672 valid_inc
= isl_pw_aff_domain(pa_inc
);
2674 is_unsigned
= iv
->getType()->isUnsignedIntegerType();
2676 assigned_value
.erase(iv
);
2677 clear_assignments
clear(assigned_value
);
2678 clear
.TraverseStmt(stmt
->getBody());
2680 id
= isl_id_alloc(ctx
, iv
->getName().str().c_str(), iv
);
2682 pa
= try_extract_nested_condition(stmt
->getCond());
2683 if (allow_nested
&& (!pa
|| has_nested(pa
)))
2686 scop
= extract(stmt
->getBody());
2688 has_affine_break
= scop
&&
2689 pet_scop_has_affine_skip(scop
, pet_skip_later
);
2690 if (has_affine_break
) {
2691 skip
= pet_scop_get_skip(scop
, pet_skip_later
);
2692 skip
= isl_set_fix_si(skip
, isl_dim_set
, 0, 1);
2693 skip
= isl_set_params(skip
);
2695 has_var_break
= scop
&& pet_scop_has_var_skip(scop
, pet_skip_later
);
2696 if (has_var_break
) {
2697 break_access
= pet_scop_get_skip_map(scop
, pet_skip_later
);
2698 keep_virtual
= true;
2701 if (pa
&& !is_nested_allowed(pa
, scop
)) {
2702 isl_pw_aff_free(pa
);
2706 if (!allow_nested
&& !pa
)
2707 pa
= try_extract_affine_condition(stmt
->getCond());
2708 valid_cond
= isl_pw_aff_domain(isl_pw_aff_copy(pa
));
2709 cond
= isl_pw_aff_non_zero_set(pa
);
2710 if (allow_nested
&& !cond
) {
2711 int save_n_stmt
= n_stmt
;
2712 test_access
= create_test_access(ctx
, n_test
++);
2714 scop_cond
= extract_non_affine_condition(stmt
->getCond(),
2715 isl_map_copy(test_access
));
2716 n_stmt
= save_n_stmt
;
2717 scop_cond
= scop_add_array(scop_cond
, test_access
, ast_context
);
2718 scop_cond
= pet_scop_prefix(scop_cond
, 0);
2719 scop
= pet_scop_reset_context(scop
);
2720 scop
= pet_scop_prefix(scop
, 1);
2721 keep_virtual
= true;
2722 cond
= isl_set_universe(isl_space_set_alloc(ctx
, 0, 0));
2725 cond
= embed(cond
, isl_id_copy(id
));
2726 skip
= embed(skip
, isl_id_copy(id
));
2727 valid_cond
= isl_set_coalesce(valid_cond
);
2728 valid_cond
= embed(valid_cond
, isl_id_copy(id
));
2729 valid_inc
= embed(valid_inc
, isl_id_copy(id
));
2730 is_one
= isl_int_is_one(inc
) || isl_int_is_negone(inc
);
2731 is_virtual
= is_unsigned
&& (!is_one
|| can_wrap(cond
, iv
, inc
));
2733 init_val
= extract_affine(rhs
);
2734 valid_cond_init
= enforce_subset(
2735 isl_set_from_pw_aff(isl_pw_aff_copy(init_val
)),
2736 isl_set_copy(valid_cond
));
2737 if (is_one
&& !is_virtual
) {
2738 isl_pw_aff_free(init_val
);
2739 pa
= extract_comparison(isl_int_is_pos(inc
) ? BO_GE
: BO_LE
,
2741 valid_init
= isl_pw_aff_domain(isl_pw_aff_copy(pa
));
2742 valid_init
= set_project_out_by_id(valid_init
, id
);
2743 domain
= isl_pw_aff_non_zero_set(pa
);
2745 valid_init
= isl_pw_aff_domain(isl_pw_aff_copy(init_val
));
2746 domain
= strided_domain(isl_id_copy(id
), init_val
, inc
);
2749 domain
= embed(domain
, isl_id_copy(id
));
2752 wrap
= compute_wrapping(isl_set_get_space(cond
), iv
);
2753 rev_wrap
= isl_map_reverse(isl_map_copy(wrap
));
2754 cond
= isl_set_apply(cond
, isl_map_copy(rev_wrap
));
2755 skip
= isl_set_apply(skip
, isl_map_copy(rev_wrap
));
2756 valid_cond
= isl_set_apply(valid_cond
, isl_map_copy(rev_wrap
));
2757 valid_inc
= isl_set_apply(valid_inc
, rev_wrap
);
2759 is_simple
= is_simple_bound(cond
, inc
);
2761 cond
= isl_set_gist(cond
, isl_set_copy(domain
));
2762 is_simple
= is_simple_bound(cond
, inc
);
2765 cond
= valid_for_each_iteration(cond
,
2766 isl_set_copy(domain
), inc
);
2767 domain
= isl_set_intersect(domain
, cond
);
2768 if (has_affine_break
) {
2769 skip
= isl_set_intersect(skip
, isl_set_copy(domain
));
2770 skip
= after(skip
, isl_int_sgn(inc
));
2771 domain
= isl_set_subtract(domain
, skip
);
2773 domain
= isl_set_set_dim_id(domain
, isl_dim_set
, 0, isl_id_copy(id
));
2774 space
= isl_space_from_domain(isl_set_get_space(domain
));
2775 space
= isl_space_add_dims(space
, isl_dim_out
, 1);
2776 sched
= isl_map_universe(space
);
2777 if (isl_int_is_pos(inc
))
2778 sched
= isl_map_equate(sched
, isl_dim_in
, 0, isl_dim_out
, 0);
2780 sched
= isl_map_oppose(sched
, isl_dim_in
, 0, isl_dim_out
, 0);
2782 valid_cond_next
= valid_on_next(valid_cond
, isl_set_copy(domain
), inc
);
2783 valid_inc
= enforce_subset(isl_set_copy(domain
), valid_inc
);
2785 if (is_virtual
&& !keep_virtual
) {
2786 wrap
= isl_map_set_dim_id(wrap
,
2787 isl_dim_out
, 0, isl_id_copy(id
));
2788 sched
= isl_map_intersect_domain(sched
, isl_set_copy(domain
));
2789 domain
= isl_set_apply(domain
, isl_map_copy(wrap
));
2790 sched
= isl_map_apply_domain(sched
, wrap
);
2792 if (!(is_virtual
&& keep_virtual
)) {
2793 space
= isl_set_get_space(domain
);
2794 wrap
= isl_map_identity(isl_space_map_from_set(space
));
2797 scop_cond
= pet_scop_embed(scop_cond
, isl_set_copy(domain
),
2798 isl_map_copy(sched
), isl_map_copy(wrap
), isl_id_copy(id
));
2799 scop
= pet_scop_embed(scop
, isl_set_copy(domain
), sched
, wrap
, id
);
2800 scop
= resolve_nested(scop
);
2802 scop
= scop_add_break(scop
, break_access
, isl_set_copy(domain
),
2805 scop
= scop_add_while(scop_cond
, scop
, test_access
, domain
,
2807 isl_set_free(valid_inc
);
2809 scop
= pet_scop_restrict_context(scop
, valid_inc
);
2810 scop
= pet_scop_restrict_context(scop
, valid_cond_next
);
2811 scop
= pet_scop_restrict_context(scop
, valid_cond_init
);
2812 isl_set_free(domain
);
2814 clear_assignment(assigned_value
, iv
);
2818 scop
= pet_scop_restrict_context(scop
, valid_init
);
2823 struct pet_scop
*PetScan::extract(CompoundStmt
*stmt
)
2825 return extract(stmt
->children());
2828 /* Does parameter "pos" of "map" refer to a nested access?
2830 static bool is_nested_parameter(__isl_keep isl_map
*map
, int pos
)
2835 id
= isl_map_get_dim_id(map
, isl_dim_param
, pos
);
2836 nested
= is_nested_parameter(id
);
2842 /* How many parameters of "space" refer to nested accesses, i.e., have no name?
2844 static int n_nested_parameter(__isl_keep isl_space
*space
)
2849 nparam
= isl_space_dim(space
, isl_dim_param
);
2850 for (int i
= 0; i
< nparam
; ++i
)
2851 if (is_nested_parameter(space
, i
))
2857 /* How many parameters of "map" refer to nested accesses, i.e., have no name?
2859 static int n_nested_parameter(__isl_keep isl_map
*map
)
2864 space
= isl_map_get_space(map
);
2865 n
= n_nested_parameter(space
);
2866 isl_space_free(space
);
2871 /* For each nested access parameter in "space",
2872 * construct a corresponding pet_expr, place it in args and
2873 * record its position in "param2pos".
2874 * "n_arg" is the number of elements that are already in args.
2875 * The position recorded in "param2pos" takes this number into account.
2876 * If the pet_expr corresponding to a parameter is identical to
2877 * the pet_expr corresponding to an earlier parameter, then these two
2878 * parameters are made to refer to the same element in args.
2880 * Return the final number of elements in args or -1 if an error has occurred.
2882 int PetScan::extract_nested(__isl_keep isl_space
*space
,
2883 int n_arg
, struct pet_expr
**args
, std::map
<int,int> ¶m2pos
)
2887 nparam
= isl_space_dim(space
, isl_dim_param
);
2888 for (int i
= 0; i
< nparam
; ++i
) {
2890 isl_id
*id
= isl_space_get_dim_id(space
, isl_dim_param
, i
);
2893 if (!is_nested_parameter(id
)) {
2898 nested
= (Expr
*) isl_id_get_user(id
);
2899 args
[n_arg
] = extract_expr(nested
);
2903 for (j
= 0; j
< n_arg
; ++j
)
2904 if (pet_expr_is_equal(args
[j
], args
[n_arg
]))
2908 pet_expr_free(args
[n_arg
]);
2912 param2pos
[i
] = n_arg
++;
2920 /* For each nested access parameter in the access relations in "expr",
2921 * construct a corresponding pet_expr, place it in expr->args and
2922 * record its position in "param2pos".
2923 * n is the number of nested access parameters.
2925 struct pet_expr
*PetScan::extract_nested(struct pet_expr
*expr
, int n
,
2926 std::map
<int,int> ¶m2pos
)
2930 expr
->args
= isl_calloc_array(ctx
, struct pet_expr
*, n
);
2935 space
= isl_map_get_space(expr
->acc
.access
);
2936 n
= extract_nested(space
, 0, expr
->args
, param2pos
);
2937 isl_space_free(space
);
2945 pet_expr_free(expr
);
2949 /* Look for parameters in any access relation in "expr" that
2950 * refer to nested accesses. In particular, these are
2951 * parameters with no name.
2953 * If there are any such parameters, then the domain of the access
2954 * relation, which is still [] at this point, is replaced by
2955 * [[] -> [t_1,...,t_n]], with n the number of these parameters
2956 * (after identifying identical nested accesses).
2957 * The parameters are then equated to the corresponding t dimensions
2958 * and subsequently projected out.
2959 * param2pos maps the position of the parameter to the position
2960 * of the corresponding t dimension.
2962 struct pet_expr
*PetScan::resolve_nested(struct pet_expr
*expr
)
2969 std::map
<int,int> param2pos
;
2974 for (int i
= 0; i
< expr
->n_arg
; ++i
) {
2975 expr
->args
[i
] = resolve_nested(expr
->args
[i
]);
2976 if (!expr
->args
[i
]) {
2977 pet_expr_free(expr
);
2982 if (expr
->type
!= pet_expr_access
)
2985 n
= n_nested_parameter(expr
->acc
.access
);
2989 expr
= extract_nested(expr
, n
, param2pos
);
2994 nparam
= isl_map_dim(expr
->acc
.access
, isl_dim_param
);
2995 n_in
= isl_map_dim(expr
->acc
.access
, isl_dim_in
);
2996 dim
= isl_map_get_space(expr
->acc
.access
);
2997 dim
= isl_space_domain(dim
);
2998 dim
= isl_space_from_domain(dim
);
2999 dim
= isl_space_add_dims(dim
, isl_dim_out
, n
);
3000 map
= isl_map_universe(dim
);
3001 map
= isl_map_domain_map(map
);
3002 map
= isl_map_reverse(map
);
3003 expr
->acc
.access
= isl_map_apply_domain(expr
->acc
.access
, map
);
3005 for (int i
= nparam
- 1; i
>= 0; --i
) {
3006 isl_id
*id
= isl_map_get_dim_id(expr
->acc
.access
,
3008 if (!is_nested_parameter(id
)) {
3013 expr
->acc
.access
= isl_map_equate(expr
->acc
.access
,
3014 isl_dim_param
, i
, isl_dim_in
,
3015 n_in
+ param2pos
[i
]);
3016 expr
->acc
.access
= isl_map_project_out(expr
->acc
.access
,
3017 isl_dim_param
, i
, 1);
3024 pet_expr_free(expr
);
3028 /* Convert a top-level pet_expr to a pet_scop with one statement.
3029 * This mainly involves resolving nested expression parameters
3030 * and setting the name of the iteration space.
3031 * The name is given by "label" if it is non-NULL. Otherwise,
3032 * it is of the form S_<n_stmt>.
3034 struct pet_scop
*PetScan::extract(Stmt
*stmt
, struct pet_expr
*expr
,
3035 __isl_take isl_id
*label
)
3037 struct pet_stmt
*ps
;
3038 SourceLocation loc
= stmt
->getLocStart();
3039 int line
= PP
.getSourceManager().getExpansionLineNumber(loc
);
3041 expr
= resolve_nested(expr
);
3042 ps
= pet_stmt_from_pet_expr(ctx
, line
, label
, n_stmt
++, expr
);
3043 return pet_scop_from_pet_stmt(ctx
, ps
);
3046 /* Check if we can extract an affine expression from "expr".
3047 * Return the expressions as an isl_pw_aff if we can and NULL otherwise.
3048 * We turn on autodetection so that we won't generate any warnings
3049 * and turn off nesting, so that we won't accept any non-affine constructs.
3051 __isl_give isl_pw_aff
*PetScan::try_extract_affine(Expr
*expr
)
3054 int save_autodetect
= options
->autodetect
;
3055 bool save_nesting
= nesting_enabled
;
3057 options
->autodetect
= 1;
3058 nesting_enabled
= false;
3060 pwaff
= extract_affine(expr
);
3062 options
->autodetect
= save_autodetect
;
3063 nesting_enabled
= save_nesting
;
3068 /* Check whether "expr" is an affine expression.
3070 bool PetScan::is_affine(Expr
*expr
)
3074 pwaff
= try_extract_affine(expr
);
3075 isl_pw_aff_free(pwaff
);
3077 return pwaff
!= NULL
;
3080 /* Check if we can extract an affine constraint from "expr".
3081 * Return the constraint as an isl_set if we can and NULL otherwise.
3082 * We turn on autodetection so that we won't generate any warnings
3083 * and turn off nesting, so that we won't accept any non-affine constructs.
3085 __isl_give isl_pw_aff
*PetScan::try_extract_affine_condition(Expr
*expr
)
3088 int save_autodetect
= options
->autodetect
;
3089 bool save_nesting
= nesting_enabled
;
3091 options
->autodetect
= 1;
3092 nesting_enabled
= false;
3094 cond
= extract_condition(expr
);
3096 options
->autodetect
= save_autodetect
;
3097 nesting_enabled
= save_nesting
;
3102 /* Check whether "expr" is an affine constraint.
3104 bool PetScan::is_affine_condition(Expr
*expr
)
3108 cond
= try_extract_affine_condition(expr
);
3109 isl_pw_aff_free(cond
);
3111 return cond
!= NULL
;
3114 /* Check if we can extract a condition from "expr".
3115 * Return the condition as an isl_pw_aff if we can and NULL otherwise.
3116 * If allow_nested is set, then the condition may involve parameters
3117 * corresponding to nested accesses.
3118 * We turn on autodetection so that we won't generate any warnings.
3120 __isl_give isl_pw_aff
*PetScan::try_extract_nested_condition(Expr
*expr
)
3123 int save_autodetect
= options
->autodetect
;
3124 bool save_nesting
= nesting_enabled
;
3126 options
->autodetect
= 1;
3127 nesting_enabled
= allow_nested
;
3128 cond
= extract_condition(expr
);
3130 options
->autodetect
= save_autodetect
;
3131 nesting_enabled
= save_nesting
;
3136 /* If the top-level expression of "stmt" is an assignment, then
3137 * return that assignment as a BinaryOperator.
3138 * Otherwise return NULL.
3140 static BinaryOperator
*top_assignment_or_null(Stmt
*stmt
)
3142 BinaryOperator
*ass
;
3146 if (stmt
->getStmtClass() != Stmt::BinaryOperatorClass
)
3149 ass
= cast
<BinaryOperator
>(stmt
);
3150 if(ass
->getOpcode() != BO_Assign
)
3156 /* Check if the given if statement is a conditional assignement
3157 * with a non-affine condition. If so, construct a pet_scop
3158 * corresponding to this conditional assignment. Otherwise return NULL.
3160 * In particular we check if "stmt" is of the form
3167 * where a is some array or scalar access.
3168 * The constructed pet_scop then corresponds to the expression
3170 * a = condition ? f(...) : g(...)
3172 * All access relations in f(...) are intersected with condition
3173 * while all access relation in g(...) are intersected with the complement.
3175 struct pet_scop
*PetScan::extract_conditional_assignment(IfStmt
*stmt
)
3177 BinaryOperator
*ass_then
, *ass_else
;
3178 isl_map
*write_then
, *write_else
;
3179 isl_set
*cond
, *comp
;
3183 struct pet_expr
*pe_cond
, *pe_then
, *pe_else
, *pe
, *pe_write
;
3184 bool save_nesting
= nesting_enabled
;
3186 if (!options
->detect_conditional_assignment
)
3189 ass_then
= top_assignment_or_null(stmt
->getThen());
3190 ass_else
= top_assignment_or_null(stmt
->getElse());
3192 if (!ass_then
|| !ass_else
)
3195 if (is_affine_condition(stmt
->getCond()))
3198 write_then
= extract_access(ass_then
->getLHS());
3199 write_else
= extract_access(ass_else
->getLHS());
3201 equal
= isl_map_is_equal(write_then
, write_else
);
3202 isl_map_free(write_else
);
3203 if (equal
< 0 || !equal
) {
3204 isl_map_free(write_then
);
3208 nesting_enabled
= allow_nested
;
3209 pa
= extract_condition(stmt
->getCond());
3210 nesting_enabled
= save_nesting
;
3211 cond
= isl_pw_aff_non_zero_set(isl_pw_aff_copy(pa
));
3212 comp
= isl_pw_aff_zero_set(isl_pw_aff_copy(pa
));
3213 map
= isl_map_from_range(isl_set_from_pw_aff(pa
));
3215 pe_cond
= pet_expr_from_access(map
);
3217 pe_then
= extract_expr(ass_then
->getRHS());
3218 pe_then
= pet_expr_restrict(pe_then
, cond
);
3219 pe_else
= extract_expr(ass_else
->getRHS());
3220 pe_else
= pet_expr_restrict(pe_else
, comp
);
3222 pe
= pet_expr_new_ternary(ctx
, pe_cond
, pe_then
, pe_else
);
3223 pe_write
= pet_expr_from_access(write_then
);
3225 pe_write
->acc
.write
= 1;
3226 pe_write
->acc
.read
= 0;
3228 pe
= pet_expr_new_binary(ctx
, pet_op_assign
, pe_write
, pe
);
3229 return extract(stmt
, pe
);
3232 /* Create a pet_scop with a single statement evaluating "cond"
3233 * and writing the result to a virtual scalar, as expressed by
3236 struct pet_scop
*PetScan::extract_non_affine_condition(Expr
*cond
,
3237 __isl_take isl_map
*access
)
3239 struct pet_expr
*expr
, *write
;
3240 struct pet_stmt
*ps
;
3241 struct pet_scop
*scop
;
3242 SourceLocation loc
= cond
->getLocStart();
3243 int line
= PP
.getSourceManager().getExpansionLineNumber(loc
);
3245 write
= pet_expr_from_access(access
);
3247 write
->acc
.write
= 1;
3248 write
->acc
.read
= 0;
3250 expr
= extract_expr(cond
);
3251 expr
= resolve_nested(expr
);
3252 expr
= pet_expr_new_binary(ctx
, pet_op_assign
, write
, expr
);
3253 ps
= pet_stmt_from_pet_expr(ctx
, line
, NULL
, n_stmt
++, expr
);
3254 scop
= pet_scop_from_pet_stmt(ctx
, ps
);
3255 scop
= resolve_nested(scop
);
3261 static __isl_give isl_map
*embed_access(__isl_take isl_map
*access
,
3265 /* Apply the map pointed to by "user" to the domain of the access
3266 * relation, thereby embedding it in the range of the map.
3267 * The domain of both relations is the zero-dimensional domain.
3269 static __isl_give isl_map
*embed_access(__isl_take isl_map
*access
, void *user
)
3271 isl_map
*map
= (isl_map
*) user
;
3273 return isl_map_apply_domain(access
, isl_map_copy(map
));
3276 /* Apply "map" to all access relations in "expr".
3278 static struct pet_expr
*embed(struct pet_expr
*expr
, __isl_keep isl_map
*map
)
3280 return pet_expr_foreach_access(expr
, &embed_access
, map
);
3283 /* How many parameters of "set" refer to nested accesses, i.e., have no name?
3285 static int n_nested_parameter(__isl_keep isl_set
*set
)
3290 space
= isl_set_get_space(set
);
3291 n
= n_nested_parameter(space
);
3292 isl_space_free(space
);
3297 /* Remove all parameters from "map" that refer to nested accesses.
3299 static __isl_give isl_map
*remove_nested_parameters(__isl_take isl_map
*map
)
3304 space
= isl_map_get_space(map
);
3305 nparam
= isl_space_dim(space
, isl_dim_param
);
3306 for (int i
= nparam
- 1; i
>= 0; --i
)
3307 if (is_nested_parameter(space
, i
))
3308 map
= isl_map_project_out(map
, isl_dim_param
, i
, 1);
3309 isl_space_free(space
);
3315 static __isl_give isl_map
*access_remove_nested_parameters(
3316 __isl_take isl_map
*access
, void *user
);
3319 static __isl_give isl_map
*access_remove_nested_parameters(
3320 __isl_take isl_map
*access
, void *user
)
3322 return remove_nested_parameters(access
);
3325 /* Remove all nested access parameters from the schedule and all
3326 * accesses of "stmt".
3327 * There is no need to remove them from the domain as these parameters
3328 * have already been removed from the domain when this function is called.
3330 static struct pet_stmt
*remove_nested_parameters(struct pet_stmt
*stmt
)
3334 stmt
->schedule
= remove_nested_parameters(stmt
->schedule
);
3335 stmt
->body
= pet_expr_foreach_access(stmt
->body
,
3336 &access_remove_nested_parameters
, NULL
);
3337 if (!stmt
->schedule
|| !stmt
->body
)
3339 for (int i
= 0; i
< stmt
->n_arg
; ++i
) {
3340 stmt
->args
[i
] = pet_expr_foreach_access(stmt
->args
[i
],
3341 &access_remove_nested_parameters
, NULL
);
3348 pet_stmt_free(stmt
);
3352 /* For each nested access parameter in the domain of "stmt",
3353 * construct a corresponding pet_expr, place it before the original
3354 * elements in stmt->args and record its position in "param2pos".
3355 * n is the number of nested access parameters.
3357 struct pet_stmt
*PetScan::extract_nested(struct pet_stmt
*stmt
, int n
,
3358 std::map
<int,int> ¶m2pos
)
3363 struct pet_expr
**args
;
3365 n_arg
= stmt
->n_arg
;
3366 args
= isl_calloc_array(ctx
, struct pet_expr
*, n
+ n_arg
);
3370 space
= isl_set_get_space(stmt
->domain
);
3371 n_arg
= extract_nested(space
, 0, args
, param2pos
);
3372 isl_space_free(space
);
3377 for (i
= 0; i
< stmt
->n_arg
; ++i
)
3378 args
[n_arg
+ i
] = stmt
->args
[i
];
3381 stmt
->n_arg
+= n_arg
;
3386 for (i
= 0; i
< n
; ++i
)
3387 pet_expr_free(args
[i
]);
3390 pet_stmt_free(stmt
);
3394 /* Check whether any of the arguments i of "stmt" starting at position "n"
3395 * is equal to one of the first "n" arguments j.
3396 * If so, combine the constraints on arguments i and j and remove
3399 static struct pet_stmt
*remove_duplicate_arguments(struct pet_stmt
*stmt
, int n
)
3408 if (n
== stmt
->n_arg
)
3411 map
= isl_set_unwrap(stmt
->domain
);
3413 for (i
= stmt
->n_arg
- 1; i
>= n
; --i
) {
3414 for (j
= 0; j
< n
; ++j
)
3415 if (pet_expr_is_equal(stmt
->args
[i
], stmt
->args
[j
]))
3420 map
= isl_map_equate(map
, isl_dim_out
, i
, isl_dim_out
, j
);
3421 map
= isl_map_project_out(map
, isl_dim_out
, i
, 1);
3423 pet_expr_free(stmt
->args
[i
]);
3424 for (j
= i
; j
+ 1 < stmt
->n_arg
; ++j
)
3425 stmt
->args
[j
] = stmt
->args
[j
+ 1];
3429 stmt
->domain
= isl_map_wrap(map
);
3434 pet_stmt_free(stmt
);
3438 /* Look for parameters in the iteration domain of "stmt" that
3439 * refer to nested accesses. In particular, these are
3440 * parameters with no name.
3442 * If there are any such parameters, then as many extra variables
3443 * (after identifying identical nested accesses) are inserted in the
3444 * range of the map wrapped inside the domain, before the original variables.
3445 * If the original domain is not a wrapped map, then a new wrapped
3446 * map is created with zero output dimensions.
3447 * The parameters are then equated to the corresponding output dimensions
3448 * and subsequently projected out, from the iteration domain,
3449 * the schedule and the access relations.
3450 * For each of the output dimensions, a corresponding argument
3451 * expression is inserted. Initially they are created with
3452 * a zero-dimensional domain, so they have to be embedded
3453 * in the current iteration domain.
3454 * param2pos maps the position of the parameter to the position
3455 * of the corresponding output dimension in the wrapped map.
3457 struct pet_stmt
*PetScan::resolve_nested(struct pet_stmt
*stmt
)
3463 std::map
<int,int> param2pos
;
3468 n
= n_nested_parameter(stmt
->domain
);
3472 n_arg
= stmt
->n_arg
;
3473 stmt
= extract_nested(stmt
, n
, param2pos
);
3477 n
= stmt
->n_arg
- n_arg
;
3478 nparam
= isl_set_dim(stmt
->domain
, isl_dim_param
);
3479 if (isl_set_is_wrapping(stmt
->domain
))
3480 map
= isl_set_unwrap(stmt
->domain
);
3482 map
= isl_map_from_domain(stmt
->domain
);
3483 map
= isl_map_insert_dims(map
, isl_dim_out
, 0, n
);
3485 for (int i
= nparam
- 1; i
>= 0; --i
) {
3488 if (!is_nested_parameter(map
, i
))
3491 id
= isl_map_get_tuple_id(stmt
->args
[param2pos
[i
]]->acc
.access
,
3493 map
= isl_map_set_dim_id(map
, isl_dim_out
, param2pos
[i
], id
);
3494 map
= isl_map_equate(map
, isl_dim_param
, i
, isl_dim_out
,
3496 map
= isl_map_project_out(map
, isl_dim_param
, i
, 1);
3499 stmt
->domain
= isl_map_wrap(map
);
3501 map
= isl_set_unwrap(isl_set_copy(stmt
->domain
));
3502 map
= isl_map_from_range(isl_map_domain(map
));
3503 for (int pos
= 0; pos
< n
; ++pos
)
3504 stmt
->args
[pos
] = embed(stmt
->args
[pos
], map
);
3507 stmt
= remove_nested_parameters(stmt
);
3508 stmt
= remove_duplicate_arguments(stmt
, n
);
3512 pet_stmt_free(stmt
);
3516 /* For each statement in "scop", move the parameters that correspond
3517 * to nested access into the ranges of the domains and create
3518 * corresponding argument expressions.
3520 struct pet_scop
*PetScan::resolve_nested(struct pet_scop
*scop
)
3525 for (int i
= 0; i
< scop
->n_stmt
; ++i
) {
3526 scop
->stmts
[i
] = resolve_nested(scop
->stmts
[i
]);
3527 if (!scop
->stmts
[i
])
3533 pet_scop_free(scop
);
3537 /* Given an access expression "expr", is the variable accessed by
3538 * "expr" assigned anywhere inside "scop"?
3540 static bool is_assigned(pet_expr
*expr
, pet_scop
*scop
)
3542 bool assigned
= false;
3545 id
= isl_map_get_tuple_id(expr
->acc
.access
, isl_dim_out
);
3546 assigned
= pet_scop_writes(scop
, id
);
3552 /* Are all nested access parameters in "pa" allowed given "scop".
3553 * In particular, is none of them written by anywhere inside "scop".
3555 * If "scop" has any skip conditions, then no nested access parameters
3556 * are allowed. In particular, if there is any nested access in a guard
3557 * for a piece of code containing a "continue", then we want to introduce
3558 * a separate statement for evaluating this guard so that we can express
3559 * that the result is false for all previous iterations.
3561 bool PetScan::is_nested_allowed(__isl_keep isl_pw_aff
*pa
, pet_scop
*scop
)
3568 nparam
= isl_pw_aff_dim(pa
, isl_dim_param
);
3569 for (int i
= 0; i
< nparam
; ++i
) {
3571 isl_id
*id
= isl_pw_aff_get_dim_id(pa
, isl_dim_param
, i
);
3575 if (!is_nested_parameter(id
)) {
3580 if (pet_scop_has_skip(scop
, pet_skip_now
)) {
3585 nested
= (Expr
*) isl_id_get_user(id
);
3586 expr
= extract_expr(nested
);
3587 allowed
= expr
&& expr
->type
== pet_expr_access
&&
3588 !is_assigned(expr
, scop
);
3590 pet_expr_free(expr
);
3600 /* Do we need to construct a skip condition of the given type
3601 * on an if statement, given that the if condition is non-affine?
3603 * pet_scop_filter_skip can only handle the case where the if condition
3604 * holds (the then branch) and the skip condition is universal.
3605 * In any other case, we need to construct a new skip condition.
3607 static bool need_skip(struct pet_scop
*scop_then
, struct pet_scop
*scop_else
,
3608 bool have_else
, enum pet_skip type
)
3610 if (have_else
&& scop_else
&& pet_scop_has_skip(scop_else
, type
))
3612 if (scop_then
&& pet_scop_has_skip(scop_then
, type
) &&
3613 !pet_scop_has_universal_skip(scop_then
, type
))
3618 /* Do we need to construct a skip condition of the given type
3619 * on an if statement, given that the if condition is affine?
3621 * There is no need to construct a new skip condition if all
3622 * the skip conditions are affine.
3624 static bool need_skip_aff(struct pet_scop
*scop_then
,
3625 struct pet_scop
*scop_else
, bool have_else
, enum pet_skip type
)
3627 if (scop_then
&& pet_scop_has_var_skip(scop_then
, type
))
3629 if (have_else
&& scop_else
&& pet_scop_has_var_skip(scop_else
, type
))
3634 /* Do we need to construct a skip condition of the given type
3635 * on an if statement?
3637 static bool need_skip(struct pet_scop
*scop_then
, struct pet_scop
*scop_else
,
3638 bool have_else
, enum pet_skip type
, bool affine
)
3641 return need_skip_aff(scop_then
, scop_else
, have_else
, type
);
3643 return need_skip(scop_then
, scop_else
, have_else
, type
);
3646 /* Construct an affine expression pet_expr that is evaluates
3647 * to the constant "val".
3649 static struct pet_expr
*universally(isl_ctx
*ctx
, int val
)
3654 space
= isl_space_alloc(ctx
, 0, 0, 1);
3655 map
= isl_map_universe(space
);
3656 map
= isl_map_fix_si(map
, isl_dim_out
, 0, val
);
3658 return pet_expr_from_access(map
);
3661 /* Construct an affine expression pet_expr that is evaluates
3662 * to the constant 1.
3664 static struct pet_expr
*universally_true(isl_ctx
*ctx
)
3666 return universally(ctx
, 1);
3669 /* Construct an affine expression pet_expr that is evaluates
3670 * to the constant 0.
3672 static struct pet_expr
*universally_false(isl_ctx
*ctx
)
3674 return universally(ctx
, 0);
3677 /* Given an access relation "test_access" for the if condition,
3678 * an access relation "skip_access" for the skip condition and
3679 * scops for the then and else branches, construct a scop for
3680 * computing "skip_access".
3682 * The computed scop contains a single statement that essentially does
3684 * skip_cond = test_cond ? skip_cond_then : skip_cond_else
3686 * If the skip conditions of the then and/or else branch are not affine,
3687 * then they need to be filtered by test_access.
3688 * If they are missing, then this means the skip condition is false.
3690 * Since we are constructing a skip condition for the if statement,
3691 * the skip conditions on the then and else branches are removed.
3693 static struct pet_scop
*extract_skip(PetScan
*scan
,
3694 __isl_take isl_map
*test_access
, __isl_take isl_map
*skip_access
,
3695 struct pet_scop
*scop_then
, struct pet_scop
*scop_else
, bool have_else
,
3698 struct pet_expr
*expr_then
, *expr_else
, *expr
, *expr_skip
;
3699 struct pet_stmt
*stmt
;
3700 struct pet_scop
*scop
;
3701 isl_ctx
*ctx
= scan
->ctx
;
3705 if (have_else
&& !scop_else
)
3708 if (pet_scop_has_skip(scop_then
, type
)) {
3709 expr_then
= pet_scop_get_skip_expr(scop_then
, type
);
3710 pet_scop_reset_skip(scop_then
, type
);
3711 if (!pet_expr_is_affine(expr_then
))
3712 expr_then
= pet_expr_filter(expr_then
,
3713 isl_map_copy(test_access
), 1);
3715 expr_then
= universally_false(ctx
);
3717 if (have_else
&& pet_scop_has_skip(scop_else
, type
)) {
3718 expr_else
= pet_scop_get_skip_expr(scop_else
, type
);
3719 pet_scop_reset_skip(scop_else
, type
);
3720 if (!pet_expr_is_affine(expr_else
))
3721 expr_else
= pet_expr_filter(expr_else
,
3722 isl_map_copy(test_access
), 0);
3724 expr_else
= universally_false(ctx
);
3726 expr
= pet_expr_from_access(test_access
);
3727 expr
= pet_expr_new_ternary(ctx
, expr
, expr_then
, expr_else
);
3728 expr_skip
= pet_expr_from_access(isl_map_copy(skip_access
));
3730 expr_skip
->acc
.write
= 1;
3731 expr_skip
->acc
.read
= 0;
3733 expr
= pet_expr_new_binary(ctx
, pet_op_assign
, expr_skip
, expr
);
3734 stmt
= pet_stmt_from_pet_expr(ctx
, -1, NULL
, scan
->n_stmt
++, expr
);
3736 scop
= pet_scop_from_pet_stmt(ctx
, stmt
);
3737 scop
= scop_add_array(scop
, skip_access
, scan
->ast_context
);
3738 isl_map_free(skip_access
);
3742 isl_map_free(test_access
);
3743 isl_map_free(skip_access
);
3747 /* Is scop's skip_now condition equal to its skip_later condition?
3748 * In particular, this means that it either has no skip_now condition
3749 * or both a skip_now and a skip_later condition (that are equal to each other).
3751 static bool skip_equals_skip_later(struct pet_scop
*scop
)
3753 int has_skip_now
, has_skip_later
;
3755 isl_set
*skip_now
, *skip_later
;
3759 has_skip_now
= pet_scop_has_skip(scop
, pet_skip_now
);
3760 has_skip_later
= pet_scop_has_skip(scop
, pet_skip_later
);
3761 if (has_skip_now
!= has_skip_later
)
3766 skip_now
= pet_scop_get_skip(scop
, pet_skip_now
);
3767 skip_later
= pet_scop_get_skip(scop
, pet_skip_later
);
3768 equal
= isl_set_is_equal(skip_now
, skip_later
);
3769 isl_set_free(skip_now
);
3770 isl_set_free(skip_later
);
3775 /* Drop the skip conditions of type pet_skip_later from scop1 and scop2.
3777 static void drop_skip_later(struct pet_scop
*scop1
, struct pet_scop
*scop2
)
3779 pet_scop_reset_skip(scop1
, pet_skip_later
);
3780 pet_scop_reset_skip(scop2
, pet_skip_later
);
3783 /* Structure that handles the construction of skip conditions.
3785 * scop_then and scop_else represent the then and else branches
3786 * of the if statement
3788 * skip[type] is true if we need to construct a skip condition of that type
3789 * equal is set if the skip conditions of types pet_skip_now and pet_skip_later
3790 * are equal to each other
3791 * access[type] is the virtual array representing the skip condition
3792 * scop[type] is a scop for computing the skip condition
3794 struct pet_skip_info
{
3800 struct pet_scop
*scop
[2];
3802 pet_skip_info(isl_ctx
*ctx
) : ctx(ctx
) {}
3804 operator bool() { return skip
[pet_skip_now
] || skip
[pet_skip_later
]; }
3807 /* Structure that handles the construction of skip conditions on if statements.
3809 * scop_then and scop_else represent the then and else branches
3810 * of the if statement
3812 struct pet_skip_info_if
: public pet_skip_info
{
3813 struct pet_scop
*scop_then
, *scop_else
;
3816 pet_skip_info_if(isl_ctx
*ctx
, struct pet_scop
*scop_then
,
3817 struct pet_scop
*scop_else
, bool have_else
, bool affine
);
3818 void extract(PetScan
*scan
, __isl_keep isl_map
*access
,
3819 enum pet_skip type
);
3820 void extract(PetScan
*scan
, __isl_keep isl_map
*access
);
3821 void extract(PetScan
*scan
, __isl_keep isl_pw_aff
*cond
);
3822 struct pet_scop
*add(struct pet_scop
*scop
, enum pet_skip type
,
3824 struct pet_scop
*add(struct pet_scop
*scop
, int offset
);
3827 /* Initialize a pet_skip_info_if structure based on the then and else branches
3828 * and based on whether the if condition is affine or not.
3830 pet_skip_info_if::pet_skip_info_if(isl_ctx
*ctx
, struct pet_scop
*scop_then
,
3831 struct pet_scop
*scop_else
, bool have_else
, bool affine
) :
3832 pet_skip_info(ctx
), scop_then(scop_then
), scop_else(scop_else
),
3833 have_else(have_else
)
3835 skip
[pet_skip_now
] =
3836 need_skip(scop_then
, scop_else
, have_else
, pet_skip_now
, affine
);
3837 equal
= skip
[pet_skip_now
] && skip_equals_skip_later(scop_then
) &&
3838 (!have_else
|| skip_equals_skip_later(scop_else
));
3839 skip
[pet_skip_later
] = skip
[pet_skip_now
] && !equal
&&
3840 need_skip(scop_then
, scop_else
, have_else
, pet_skip_later
, affine
);
3843 /* If we need to construct a skip condition of the given type,
3846 * "map" represents the if condition.
3848 void pet_skip_info_if::extract(PetScan
*scan
, __isl_keep isl_map
*map
,
3854 access
[type
] = create_test_access(isl_map_get_ctx(map
), scan
->n_test
++);
3855 scop
[type
] = extract_skip(scan
, isl_map_copy(map
),
3856 isl_map_copy(access
[type
]),
3857 scop_then
, scop_else
, have_else
, type
);
3860 /* Construct the required skip conditions, given the if condition "map".
3862 void pet_skip_info_if::extract(PetScan
*scan
, __isl_keep isl_map
*map
)
3864 extract(scan
, map
, pet_skip_now
);
3865 extract(scan
, map
, pet_skip_later
);
3867 drop_skip_later(scop_then
, scop_else
);
3870 /* Construct the required skip conditions, given the if condition "cond".
3872 void pet_skip_info_if::extract(PetScan
*scan
, __isl_keep isl_pw_aff
*cond
)
3877 if (!skip
[pet_skip_now
] && !skip
[pet_skip_later
])
3880 test_set
= isl_set_from_pw_aff(isl_pw_aff_copy(cond
));
3881 test
= isl_map_from_range(test_set
);
3882 extract(scan
, test
);
3886 /* Add the computed skip condition of the give type to "main" and
3887 * add the scop for computing the condition at the given offset.
3889 * If equal is set, then we only computed a skip condition for pet_skip_now,
3890 * but we also need to set it as main's pet_skip_later.
3892 struct pet_scop
*pet_skip_info_if::add(struct pet_scop
*main
,
3893 enum pet_skip type
, int offset
)
3900 skip_set
= isl_map_range(access
[type
]);
3901 access
[type
] = NULL
;
3902 scop
[type
] = pet_scop_prefix(scop
[type
], offset
);
3903 main
= pet_scop_add_par(ctx
, main
, scop
[type
]);
3907 main
= pet_scop_set_skip(main
, pet_skip_later
,
3908 isl_set_copy(skip_set
));
3910 main
= pet_scop_set_skip(main
, type
, skip_set
);
3915 /* Add the computed skip conditions to "main" and
3916 * add the scops for computing the conditions at the given offset.
3918 struct pet_scop
*pet_skip_info_if::add(struct pet_scop
*scop
, int offset
)
3920 scop
= add(scop
, pet_skip_now
, offset
);
3921 scop
= add(scop
, pet_skip_later
, offset
);
3926 /* Construct a pet_scop for a non-affine if statement.
3928 * We create a separate statement that writes the result
3929 * of the non-affine condition to a virtual scalar.
3930 * A constraint requiring the value of this virtual scalar to be one
3931 * is added to the iteration domains of the then branch.
3932 * Similarly, a constraint requiring the value of this virtual scalar
3933 * to be zero is added to the iteration domains of the else branch, if any.
3934 * We adjust the schedules to ensure that the virtual scalar is written
3935 * before it is read.
3937 * If there are any breaks or continues in the then and/or else
3938 * branches, then we may have to compute a new skip condition.
3939 * This is handled using a pet_skip_info_if object.
3940 * On initialization, the object checks if skip conditions need
3941 * to be computed. If so, it does so in "extract" and adds them in "add".
3943 struct pet_scop
*PetScan::extract_non_affine_if(Expr
*cond
,
3944 struct pet_scop
*scop_then
, struct pet_scop
*scop_else
,
3945 bool have_else
, int stmt_id
)
3947 struct pet_scop
*scop
;
3948 isl_map
*test_access
;
3949 int save_n_stmt
= n_stmt
;
3951 test_access
= create_test_access(ctx
, n_test
++);
3953 scop
= extract_non_affine_condition(cond
, isl_map_copy(test_access
));
3954 n_stmt
= save_n_stmt
;
3955 scop
= scop_add_array(scop
, test_access
, ast_context
);
3957 pet_skip_info_if
skip(ctx
, scop_then
, scop_else
, have_else
, false);
3958 skip
.extract(this, test_access
);
3960 scop
= pet_scop_prefix(scop
, 0);
3961 scop_then
= pet_scop_prefix(scop_then
, 1);
3962 scop_then
= pet_scop_filter(scop_then
, isl_map_copy(test_access
), 1);
3964 scop_else
= pet_scop_prefix(scop_else
, 1);
3965 scop_else
= pet_scop_filter(scop_else
, test_access
, 0);
3966 scop_then
= pet_scop_add_par(ctx
, scop_then
, scop_else
);
3968 isl_map_free(test_access
);
3970 scop
= pet_scop_add_seq(ctx
, scop
, scop_then
);
3972 scop
= skip
.add(scop
, 2);
3977 /* Construct a pet_scop for an if statement.
3979 * If the condition fits the pattern of a conditional assignment,
3980 * then it is handled by extract_conditional_assignment.
3981 * Otherwise, we do the following.
3983 * If the condition is affine, then the condition is added
3984 * to the iteration domains of the then branch, while the
3985 * opposite of the condition in added to the iteration domains
3986 * of the else branch, if any.
3987 * We allow the condition to be dynamic, i.e., to refer to
3988 * scalars or array elements that may be written to outside
3989 * of the given if statement. These nested accesses are then represented
3990 * as output dimensions in the wrapping iteration domain.
3991 * If it also written _inside_ the then or else branch, then
3992 * we treat the condition as non-affine.
3993 * As explained in extract_non_affine_if, this will introduce
3994 * an extra statement.
3995 * For aesthetic reasons, we want this statement to have a statement
3996 * number that is lower than those of the then and else branches.
3997 * In order to evaluate if will need such a statement, however, we
3998 * first construct scops for the then and else branches.
3999 * We therefore reserve a statement number if we might have to
4000 * introduce such an extra statement.
4002 * If the condition is not affine, then the scop is created in
4003 * extract_non_affine_if.
4005 * If there are any breaks or continues in the then and/or else
4006 * branches, then we may have to compute a new skip condition.
4007 * This is handled using a pet_skip_info_if object.
4008 * On initialization, the object checks if skip conditions need
4009 * to be computed. If so, it does so in "extract" and adds them in "add".
4011 struct pet_scop
*PetScan::extract(IfStmt
*stmt
)
4013 struct pet_scop
*scop_then
, *scop_else
= NULL
, *scop
;
4019 scop
= extract_conditional_assignment(stmt
);
4023 cond
= try_extract_nested_condition(stmt
->getCond());
4024 if (allow_nested
&& (!cond
|| has_nested(cond
)))
4028 assigned_value_cache
cache(assigned_value
);
4029 scop_then
= extract(stmt
->getThen());
4032 if (stmt
->getElse()) {
4033 assigned_value_cache
cache(assigned_value
);
4034 scop_else
= extract(stmt
->getElse());
4035 if (options
->autodetect
) {
4036 if (scop_then
&& !scop_else
) {
4038 isl_pw_aff_free(cond
);
4041 if (!scop_then
&& scop_else
) {
4043 isl_pw_aff_free(cond
);
4050 (!is_nested_allowed(cond
, scop_then
) ||
4051 (stmt
->getElse() && !is_nested_allowed(cond
, scop_else
)))) {
4052 isl_pw_aff_free(cond
);
4055 if (allow_nested
&& !cond
)
4056 return extract_non_affine_if(stmt
->getCond(), scop_then
,
4057 scop_else
, stmt
->getElse(), stmt_id
);
4060 cond
= extract_condition(stmt
->getCond());
4062 pet_skip_info_if
skip(ctx
, scop_then
, scop_else
, stmt
->getElse(), true);
4063 skip
.extract(this, cond
);
4065 valid
= isl_pw_aff_domain(isl_pw_aff_copy(cond
));
4066 set
= isl_pw_aff_non_zero_set(cond
);
4067 scop
= pet_scop_restrict(scop_then
, isl_set_copy(set
));
4069 if (stmt
->getElse()) {
4070 set
= isl_set_subtract(isl_set_copy(valid
), set
);
4071 scop_else
= pet_scop_restrict(scop_else
, set
);
4072 scop
= pet_scop_add_par(ctx
, scop
, scop_else
);
4075 scop
= resolve_nested(scop
);
4076 scop
= pet_scop_restrict_context(scop
, valid
);
4079 scop
= pet_scop_prefix(scop
, 0);
4080 scop
= skip
.add(scop
, 1);
4085 /* Try and construct a pet_scop for a label statement.
4086 * We currently only allow labels on expression statements.
4088 struct pet_scop
*PetScan::extract(LabelStmt
*stmt
)
4093 sub
= stmt
->getSubStmt();
4094 if (!isa
<Expr
>(sub
)) {
4099 label
= isl_id_alloc(ctx
, stmt
->getName(), NULL
);
4101 return extract(sub
, extract_expr(cast
<Expr
>(sub
)), label
);
4104 /* Construct a pet_scop for a continue statement.
4106 * We simply create an empty scop with a universal pet_skip_now
4107 * skip condition. This skip condition will then be taken into
4108 * account by the enclosing loop construct, possibly after
4109 * being incorporated into outer skip conditions.
4111 struct pet_scop
*PetScan::extract(ContinueStmt
*stmt
)
4117 scop
= pet_scop_empty(ctx
);
4121 space
= isl_space_set_alloc(ctx
, 0, 1);
4122 set
= isl_set_universe(space
);
4123 set
= isl_set_fix_si(set
, isl_dim_set
, 0, 1);
4124 scop
= pet_scop_set_skip(scop
, pet_skip_now
, set
);
4129 /* Construct a pet_scop for a break statement.
4131 * We simply create an empty scop with both a universal pet_skip_now
4132 * skip condition and a universal pet_skip_later skip condition.
4133 * These skip conditions will then be taken into
4134 * account by the enclosing loop construct, possibly after
4135 * being incorporated into outer skip conditions.
4137 struct pet_scop
*PetScan::extract(BreakStmt
*stmt
)
4143 scop
= pet_scop_empty(ctx
);
4147 space
= isl_space_set_alloc(ctx
, 0, 1);
4148 set
= isl_set_universe(space
);
4149 set
= isl_set_fix_si(set
, isl_dim_set
, 0, 1);
4150 scop
= pet_scop_set_skip(scop
, pet_skip_now
, isl_set_copy(set
));
4151 scop
= pet_scop_set_skip(scop
, pet_skip_later
, set
);
4156 /* Try and construct a pet_scop corresponding to "stmt".
4158 struct pet_scop
*PetScan::extract(Stmt
*stmt
)
4160 if (isa
<Expr
>(stmt
))
4161 return extract(stmt
, extract_expr(cast
<Expr
>(stmt
)));
4163 switch (stmt
->getStmtClass()) {
4164 case Stmt::WhileStmtClass
:
4165 return extract(cast
<WhileStmt
>(stmt
));
4166 case Stmt::ForStmtClass
:
4167 return extract_for(cast
<ForStmt
>(stmt
));
4168 case Stmt::IfStmtClass
:
4169 return extract(cast
<IfStmt
>(stmt
));
4170 case Stmt::CompoundStmtClass
:
4171 return extract(cast
<CompoundStmt
>(stmt
));
4172 case Stmt::LabelStmtClass
:
4173 return extract(cast
<LabelStmt
>(stmt
));
4174 case Stmt::ContinueStmtClass
:
4175 return extract(cast
<ContinueStmt
>(stmt
));
4176 case Stmt::BreakStmtClass
:
4177 return extract(cast
<BreakStmt
>(stmt
));
4185 /* Do we need to construct a skip condition of the given type
4186 * on a sequence of statements?
4188 * There is no need to construct a new skip condition if only
4189 * only of the two statements has a skip condition or if both
4190 * of their skip conditions are affine.
4192 * In principle we also don't need a new continuation variable if
4193 * the continuation of scop2 is affine, but then we would need
4194 * to allow more complicated forms of continuations.
4196 static bool need_skip_seq(struct pet_scop
*scop1
, struct pet_scop
*scop2
,
4199 if (!scop1
|| !pet_scop_has_skip(scop1
, type
))
4201 if (!scop2
|| !pet_scop_has_skip(scop2
, type
))
4203 if (pet_scop_has_affine_skip(scop1
, type
) &&
4204 pet_scop_has_affine_skip(scop2
, type
))
4209 /* Construct a scop for computing the skip condition of the given type and
4210 * with access relation "skip_access" for a sequence of two scops "scop1"
4213 * The computed scop contains a single statement that essentially does
4215 * skip_cond = skip_cond_1 ? 1 : skip_cond_2
4217 * or, in other words, skip_cond1 || skip_cond2.
4218 * In this expression, skip_cond_2 is filtered to reflect that it is
4219 * only evaluated when skip_cond_1 is false.
4221 * The skip condition on scop1 is not removed because it still needs
4222 * to be applied to scop2 when these two scops are combined.
4224 static struct pet_scop
*extract_skip_seq(PetScan
*ps
,
4225 __isl_take isl_map
*skip_access
,
4226 struct pet_scop
*scop1
, struct pet_scop
*scop2
, enum pet_skip type
)
4229 struct pet_expr
*expr1
, *expr2
, *expr
, *expr_skip
;
4230 struct pet_stmt
*stmt
;
4231 struct pet_scop
*scop
;
4232 isl_ctx
*ctx
= ps
->ctx
;
4234 if (!scop1
|| !scop2
)
4237 expr1
= pet_scop_get_skip_expr(scop1
, type
);
4238 expr2
= pet_scop_get_skip_expr(scop2
, type
);
4239 pet_scop_reset_skip(scop2
, type
);
4241 expr2
= pet_expr_filter(expr2
, isl_map_copy(expr1
->acc
.access
), 0);
4243 expr
= universally_true(ctx
);
4244 expr
= pet_expr_new_ternary(ctx
, expr1
, expr
, expr2
);
4245 expr_skip
= pet_expr_from_access(isl_map_copy(skip_access
));
4247 expr_skip
->acc
.write
= 1;
4248 expr_skip
->acc
.read
= 0;
4250 expr
= pet_expr_new_binary(ctx
, pet_op_assign
, expr_skip
, expr
);
4251 stmt
= pet_stmt_from_pet_expr(ctx
, -1, NULL
, ps
->n_stmt
++, expr
);
4253 scop
= pet_scop_from_pet_stmt(ctx
, stmt
);
4254 scop
= scop_add_array(scop
, skip_access
, ps
->ast_context
);
4255 isl_map_free(skip_access
);
4259 isl_map_free(skip_access
);
4263 /* Structure that handles the construction of skip conditions
4264 * on sequences of statements.
4266 * scop1 and scop2 represent the two statements that are combined
4268 struct pet_skip_info_seq
: public pet_skip_info
{
4269 struct pet_scop
*scop1
, *scop2
;
4271 pet_skip_info_seq(isl_ctx
*ctx
, struct pet_scop
*scop1
,
4272 struct pet_scop
*scop2
);
4273 void extract(PetScan
*scan
, enum pet_skip type
);
4274 void extract(PetScan
*scan
);
4275 struct pet_scop
*add(struct pet_scop
*scop
, enum pet_skip type
,
4277 struct pet_scop
*add(struct pet_scop
*scop
, int offset
);
4280 /* Initialize a pet_skip_info_seq structure based on
4281 * on the two statements that are going to be combined.
4283 pet_skip_info_seq::pet_skip_info_seq(isl_ctx
*ctx
, struct pet_scop
*scop1
,
4284 struct pet_scop
*scop2
) : pet_skip_info(ctx
), scop1(scop1
), scop2(scop2
)
4286 skip
[pet_skip_now
] = need_skip_seq(scop1
, scop2
, pet_skip_now
);
4287 equal
= skip
[pet_skip_now
] && skip_equals_skip_later(scop1
) &&
4288 skip_equals_skip_later(scop2
);
4289 skip
[pet_skip_later
] = skip
[pet_skip_now
] && !equal
&&
4290 need_skip_seq(scop1
, scop2
, pet_skip_later
);
4293 /* If we need to construct a skip condition of the given type,
4296 void pet_skip_info_seq::extract(PetScan
*scan
, enum pet_skip type
)
4301 access
[type
] = create_test_access(ctx
, scan
->n_test
++);
4302 scop
[type
] = extract_skip_seq(scan
, isl_map_copy(access
[type
]),
4303 scop1
, scop2
, type
);
4306 /* Construct the required skip conditions.
4308 void pet_skip_info_seq::extract(PetScan
*scan
)
4310 extract(scan
, pet_skip_now
);
4311 extract(scan
, pet_skip_later
);
4313 drop_skip_later(scop1
, scop2
);
4316 /* Add the computed skip condition of the give type to "main" and
4317 * add the scop for computing the condition at the given offset (the statement
4318 * number). Within this offset, the condition is computed at position 1
4319 * to ensure that it is computed after the corresponding statement.
4321 * If equal is set, then we only computed a skip condition for pet_skip_now,
4322 * but we also need to set it as main's pet_skip_later.
4324 struct pet_scop
*pet_skip_info_seq::add(struct pet_scop
*main
,
4325 enum pet_skip type
, int offset
)
4332 skip_set
= isl_map_range(access
[type
]);
4333 access
[type
] = NULL
;
4334 scop
[type
] = pet_scop_prefix(scop
[type
], 1);
4335 scop
[type
] = pet_scop_prefix(scop
[type
], offset
);
4336 main
= pet_scop_add_par(ctx
, main
, scop
[type
]);
4340 main
= pet_scop_set_skip(main
, pet_skip_later
,
4341 isl_set_copy(skip_set
));
4343 main
= pet_scop_set_skip(main
, type
, skip_set
);
4348 /* Add the computed skip conditions to "main" and
4349 * add the scops for computing the conditions at the given offset.
4351 struct pet_scop
*pet_skip_info_seq::add(struct pet_scop
*scop
, int offset
)
4353 scop
= add(scop
, pet_skip_now
, offset
);
4354 scop
= add(scop
, pet_skip_later
, offset
);
4359 /* Try and construct a pet_scop corresponding to (part of)
4360 * a sequence of statements.
4362 * If there are any breaks or continues in the individual statements,
4363 * then we may have to compute a new skip condition.
4364 * This is handled using a pet_skip_info_seq object.
4365 * On initialization, the object checks if skip conditions need
4366 * to be computed. If so, it does so in "extract" and adds them in "add".
4368 struct pet_scop
*PetScan::extract(StmtRange stmt_range
)
4373 bool partial_range
= false;
4375 scop
= pet_scop_empty(ctx
);
4376 for (i
= stmt_range
.first
, j
= 0; i
!= stmt_range
.second
; ++i
, ++j
) {
4378 struct pet_scop
*scop_i
;
4380 scop_i
= extract(child
);
4381 if (scop
&& partial
) {
4382 pet_scop_free(scop_i
);
4385 pet_skip_info_seq
skip(ctx
, scop
, scop_i
);
4388 scop_i
= pet_scop_prefix(scop_i
, 0);
4389 scop_i
= pet_scop_prefix(scop_i
, j
);
4390 if (options
->autodetect
) {
4392 scop
= pet_scop_add_seq(ctx
, scop
, scop_i
);
4394 partial_range
= true;
4395 if (scop
->n_stmt
!= 0 && !scop_i
)
4398 scop
= pet_scop_add_seq(ctx
, scop
, scop_i
);
4401 scop
= skip
.add(scop
, j
);
4407 if (scop
&& partial_range
)
4413 /* Return the file offset of the expansion location of "Loc".
4415 static unsigned getExpansionOffset(SourceManager
&SM
, SourceLocation Loc
)
4417 return SM
.getFileOffset(SM
.getExpansionLoc(Loc
));
4420 /* Check if the scop marked by the user is exactly this Stmt
4421 * or part of this Stmt.
4422 * If so, return a pet_scop corresponding to the marked region.
4423 * Otherwise, return NULL.
4425 struct pet_scop
*PetScan::scan(Stmt
*stmt
)
4427 SourceManager
&SM
= PP
.getSourceManager();
4428 unsigned start_off
, end_off
;
4430 start_off
= getExpansionOffset(SM
, stmt
->getLocStart());
4431 end_off
= getExpansionOffset(SM
, stmt
->getLocEnd());
4433 if (start_off
> loc
.end
)
4435 if (end_off
< loc
.start
)
4437 if (start_off
>= loc
.start
&& end_off
<= loc
.end
) {
4438 return extract(stmt
);
4442 for (start
= stmt
->child_begin(); start
!= stmt
->child_end(); ++start
) {
4443 Stmt
*child
= *start
;
4446 start_off
= getExpansionOffset(SM
, child
->getLocStart());
4447 end_off
= getExpansionOffset(SM
, child
->getLocEnd());
4448 if (start_off
< loc
.start
&& end_off
> loc
.end
)
4450 if (start_off
>= loc
.start
)
4455 for (end
= start
; end
!= stmt
->child_end(); ++end
) {
4457 start_off
= SM
.getFileOffset(child
->getLocStart());
4458 if (start_off
>= loc
.end
)
4462 return extract(StmtRange(start
, end
));
4465 /* Set the size of index "pos" of "array" to "size".
4466 * In particular, add a constraint of the form
4470 * to array->extent and a constraint of the form
4474 * to array->context.
4476 static struct pet_array
*update_size(struct pet_array
*array
, int pos
,
4477 __isl_take isl_pw_aff
*size
)
4487 valid
= isl_pw_aff_nonneg_set(isl_pw_aff_copy(size
));
4488 array
->context
= isl_set_intersect(array
->context
, valid
);
4490 dim
= isl_set_get_space(array
->extent
);
4491 aff
= isl_aff_zero_on_domain(isl_local_space_from_space(dim
));
4492 aff
= isl_aff_add_coefficient_si(aff
, isl_dim_in
, pos
, 1);
4493 univ
= isl_set_universe(isl_aff_get_domain_space(aff
));
4494 index
= isl_pw_aff_alloc(univ
, aff
);
4496 size
= isl_pw_aff_add_dims(size
, isl_dim_in
,
4497 isl_set_dim(array
->extent
, isl_dim_set
));
4498 id
= isl_set_get_tuple_id(array
->extent
);
4499 size
= isl_pw_aff_set_tuple_id(size
, isl_dim_in
, id
);
4500 bound
= isl_pw_aff_lt_set(index
, size
);
4502 array
->extent
= isl_set_intersect(array
->extent
, bound
);
4504 if (!array
->context
|| !array
->extent
)
4509 pet_array_free(array
);
4513 /* Figure out the size of the array at position "pos" and all
4514 * subsequent positions from "type" and update "array" accordingly.
4516 struct pet_array
*PetScan::set_upper_bounds(struct pet_array
*array
,
4517 const Type
*type
, int pos
)
4519 const ArrayType
*atype
;
4525 if (type
->isPointerType()) {
4526 type
= type
->getPointeeType().getTypePtr();
4527 return set_upper_bounds(array
, type
, pos
+ 1);
4529 if (!type
->isArrayType())
4532 type
= type
->getCanonicalTypeInternal().getTypePtr();
4533 atype
= cast
<ArrayType
>(type
);
4535 if (type
->isConstantArrayType()) {
4536 const ConstantArrayType
*ca
= cast
<ConstantArrayType
>(atype
);
4537 size
= extract_affine(ca
->getSize());
4538 array
= update_size(array
, pos
, size
);
4539 } else if (type
->isVariableArrayType()) {
4540 const VariableArrayType
*vla
= cast
<VariableArrayType
>(atype
);
4541 size
= extract_affine(vla
->getSizeExpr());
4542 array
= update_size(array
, pos
, size
);
4545 type
= atype
->getElementType().getTypePtr();
4547 return set_upper_bounds(array
, type
, pos
+ 1);
4550 /* Is "T" the type of a variable length array with static size?
4552 static bool is_vla_with_static_size(QualType T
)
4554 const VariableArrayType
*vlatype
;
4556 if (!T
->isVariableArrayType())
4558 vlatype
= cast
<VariableArrayType
>(T
);
4559 return vlatype
->getSizeModifier() == VariableArrayType::Static
;
4562 /* Return the type of "decl" as an array.
4564 * In particular, if "decl" is a parameter declaration that
4565 * is a variable length array with a static size, then
4566 * return the original type (i.e., the variable length array).
4567 * Otherwise, return the type of decl.
4569 static QualType
get_array_type(ValueDecl
*decl
)
4574 parm
= dyn_cast
<ParmVarDecl
>(decl
);
4576 return decl
->getType();
4578 T
= parm
->getOriginalType();
4579 if (!is_vla_with_static_size(T
))
4580 return decl
->getType();
4584 /* Construct and return a pet_array corresponding to the variable "decl".
4585 * In particular, initialize array->extent to
4587 * { name[i_1,...,i_d] : i_1,...,i_d >= 0 }
4589 * and then call set_upper_bounds to set the upper bounds on the indices
4590 * based on the type of the variable.
4592 struct pet_array
*PetScan::extract_array(isl_ctx
*ctx
, ValueDecl
*decl
)
4594 struct pet_array
*array
;
4595 QualType qt
= get_array_type(decl
);
4596 const Type
*type
= qt
.getTypePtr();
4597 int depth
= array_depth(type
);
4598 QualType base
= base_type(qt
);
4603 array
= isl_calloc_type(ctx
, struct pet_array
);
4607 id
= isl_id_alloc(ctx
, decl
->getName().str().c_str(), decl
);
4608 dim
= isl_space_set_alloc(ctx
, 0, depth
);
4609 dim
= isl_space_set_tuple_id(dim
, isl_dim_set
, id
);
4611 array
->extent
= isl_set_nat_universe(dim
);
4613 dim
= isl_space_params_alloc(ctx
, 0);
4614 array
->context
= isl_set_universe(dim
);
4616 array
= set_upper_bounds(array
, type
, 0);
4620 name
= base
.getAsString();
4621 array
->element_type
= strdup(name
.c_str());
4622 array
->element_size
= decl
->getASTContext().getTypeInfo(base
).first
/ 8;
4627 /* Construct a list of pet_arrays, one for each array (or scalar)
4628 * accessed inside "scop", add this list to "scop" and return the result.
4630 * The context of "scop" is updated with the intersection of
4631 * the contexts of all arrays, i.e., constraints on the parameters
4632 * that ensure that the arrays have a valid (non-negative) size.
4634 struct pet_scop
*PetScan::scan_arrays(struct pet_scop
*scop
)
4637 set
<ValueDecl
*> arrays
;
4638 set
<ValueDecl
*>::iterator it
;
4640 struct pet_array
**scop_arrays
;
4645 pet_scop_collect_arrays(scop
, arrays
);
4646 if (arrays
.size() == 0)
4649 n_array
= scop
->n_array
;
4651 scop_arrays
= isl_realloc_array(ctx
, scop
->arrays
, struct pet_array
*,
4652 n_array
+ arrays
.size());
4655 scop
->arrays
= scop_arrays
;
4657 for (it
= arrays
.begin(), i
= 0; it
!= arrays
.end(); ++it
, ++i
) {
4658 struct pet_array
*array
;
4659 scop
->arrays
[n_array
+ i
] = array
= extract_array(ctx
, *it
);
4660 if (!scop
->arrays
[n_array
+ i
])
4663 scop
->context
= isl_set_intersect(scop
->context
,
4664 isl_set_copy(array
->context
));
4671 pet_scop_free(scop
);
4675 /* Bound all parameters in scop->context to the possible values
4676 * of the corresponding C variable.
4678 static struct pet_scop
*add_parameter_bounds(struct pet_scop
*scop
)
4685 n
= isl_set_dim(scop
->context
, isl_dim_param
);
4686 for (int i
= 0; i
< n
; ++i
) {
4690 id
= isl_set_get_dim_id(scop
->context
, isl_dim_param
, i
);
4691 if (is_nested_parameter(id
)) {
4693 isl_die(isl_set_get_ctx(scop
->context
),
4695 "unresolved nested parameter", goto error
);
4697 decl
= (ValueDecl
*) isl_id_get_user(id
);
4700 scop
->context
= set_parameter_bounds(scop
->context
, i
, decl
);
4708 pet_scop_free(scop
);
4712 /* Construct a pet_scop from the given function.
4714 struct pet_scop
*PetScan::scan(FunctionDecl
*fd
)
4719 stmt
= fd
->getBody();
4721 if (options
->autodetect
)
4722 scop
= extract(stmt
);
4725 scop
= pet_scop_detect_parameter_accesses(scop
);
4726 scop
= scan_arrays(scop
);
4727 scop
= add_parameter_bounds(scop
);
4728 scop
= pet_scop_gist(scop
, value_bounds
);