#ifndef LLVM_ANALYSIS_SCALAREVOLUTION_EXPANDER_H
#define LLVM_ANALYSIS_SCALAREVOLUTION_EXPANDER_H
-#include "llvm/Instructions.h"
-#include "llvm/Type.h"
-#include "llvm/Analysis/ScalarEvolution.h"
#include "llvm/Analysis/ScalarEvolutionExpressions.h"
+#include "llvm/Analysis/ScalarEvolutionNormalization.h"
+#include "llvm/Support/IRBuilder.h"
+#include "llvm/Support/TargetFolder.h"
+#include <set>
namespace llvm {
/// SCEVExpander - This class uses information about analyze scalars to
/// rewrite expressions in canonical form.
///
/// Clients should create an instance of this class when rewriting is needed,
- /// and destroy it when finished to allow the release of the associated
+ /// and destroy it when finished to allow the release of the associated
/// memory.
- struct SCEVExpander : public SCEVVisitor<SCEVExpander, Value*> {
+ class SCEVExpander : public SCEVVisitor<SCEVExpander, Value*> {
ScalarEvolution &SE;
- LoopInfo &LI;
- std::map<SCEVHandle, Value*> InsertedExpressions;
+ std::map<std::pair<const SCEV *, Instruction *>, AssertingVH<Value> >
+ InsertedExpressions;
std::set<Value*> InsertedValues;
- BasicBlock::iterator InsertPt;
+ /// PostIncLoops - Addrecs referring to any of the given loops are expanded
+ /// in post-inc mode. For example, expanding {1,+,1}<L> in post-inc mode
+ /// returns the add instruction that adds one to the phi for {0,+,1}<L>,
+ /// as opposed to a new phi starting at 1. This is only supported in
+ /// non-canonical mode.
+ PostIncLoopSet PostIncLoops;
+
+ /// IVIncInsertPos - When this is non-null, addrecs expanded in the
+ /// loop it indicates should be inserted with increments at
+ /// IVIncInsertPos.
+ const Loop *IVIncInsertLoop;
+
+ /// IVIncInsertPos - When expanding addrecs in the IVIncInsertLoop loop,
+ /// insert the IV increment at this position.
+ Instruction *IVIncInsertPos;
+
+ /// CanonicalMode - When true, expressions are expanded in "canonical"
+ /// form. In particular, addrecs are expanded as arithmetic based on
+ /// a canonical induction variable. When false, expression are expanded
+ /// in a more literal form.
+ bool CanonicalMode;
+
+ typedef IRBuilder<true, TargetFolder> BuilderType;
+ BuilderType Builder;
friend struct SCEVVisitor<SCEVExpander, Value*>;
- public:
- SCEVExpander(ScalarEvolution &se, LoopInfo &li)
- : SE(se), LI(li) {}
- LoopInfo &getLoopInfo() const { return LI; }
+ public:
+ /// SCEVExpander - Construct a SCEVExpander in "canonical" mode.
+ explicit SCEVExpander(ScalarEvolution &se)
+ : SE(se), IVIncInsertLoop(0), CanonicalMode(true),
+ Builder(se.getContext(), TargetFolder(se.TD)) {}
/// clear - Erase the contents of the InsertedExpressions map so that users
/// trying to expand the same expression into multiple BasicBlocks or
/// different places within the same BasicBlock can do so.
void clear() { InsertedExpressions.clear(); }
- /// isInsertedInstruction - Return true if the specified instruction was
- /// inserted by the code rewriter. If so, the client should not modify the
- /// instruction.
- bool isInsertedInstruction(Instruction *I) const {
- return InsertedValues.count(I);
- }
-
- /// isInsertedExpression - Return true if the the code rewriter has a
- /// Value* recorded for the given expression.
- bool isInsertedExpression(const SCEV *S) const {
- return InsertedExpressions.count(S);
- }
-
/// getOrInsertCanonicalInductionVariable - This method returns the
/// canonical induction variable of the specified type for the specified
/// loop (inserting one if there is none). A canonical induction variable
/// starts at zero and steps by one on each iteration.
- Value *getOrInsertCanonicalInductionVariable(const Loop *L, const Type *Ty){
- assert(Ty->isInteger() && "Can only insert integer induction variables!");
- SCEVHandle H = SE.getAddRecExpr(SE.getIntegerSCEV(0, Ty),
- SE.getIntegerSCEV(1, Ty), L);
- return expand(H);
- }
+ Value *getOrInsertCanonicalInductionVariable(const Loop *L, const Type *Ty);
- /// addInsertedValue - Remember the specified instruction as being the
- /// canonical form for the specified SCEV.
- void addInsertedValue(Value *V, const SCEV *S) {
- InsertedExpressions[S] = V;
- InsertedValues.insert(V);
+ /// expandCodeFor - Insert code to directly compute the specified SCEV
+ /// expression into the program. The inserted code is inserted into the
+ /// specified block.
+ Value *expandCodeFor(const SCEV *SH, const Type *Ty, Instruction *I);
+
+ /// setIVIncInsertPos - Set the current IV increment loop and position.
+ void setIVIncInsertPos(const Loop *L, Instruction *Pos) {
+ assert(!CanonicalMode &&
+ "IV increment positions are not supported in CanonicalMode");
+ IVIncInsertLoop = L;
+ IVIncInsertPos = Pos;
}
- void setInsertionPoint(BasicBlock::iterator NewIP) { InsertPt = NewIP; }
+ /// setPostInc - Enable post-inc expansion for addrecs referring to the
+ /// given loops. Post-inc expansion is only supported in non-canonical
+ /// mode.
+ void setPostInc(const PostIncLoopSet &L) {
+ assert(!CanonicalMode &&
+ "Post-inc expansion is not supported in CanonicalMode");
+ PostIncLoops = L;
+ }
- BasicBlock::iterator getInsertionPoint() const { return InsertPt; }
+ /// clearPostInc - Disable all post-inc expansion.
+ void clearPostInc() {
+ PostIncLoops.clear();
+ }
- /// expandCodeFor - Insert code to directly compute the specified SCEV
- /// expression into the program. The inserted code is inserted into the
- /// SCEVExpander's current insertion point.
- Value *expandCodeFor(SCEVHandle SH, const Type *Ty);
+ /// disableCanonicalMode - Disable the behavior of expanding expressions in
+ /// canonical form rather than in a more literal form. Non-canonical mode
+ /// is useful for late optimization passes.
+ void disableCanonicalMode() { CanonicalMode = false; }
- /// expandCodeFor - Insert code to directly compute the specified SCEV
- /// expression into the program. The inserted code is inserted into the
- /// specified block.
- Value *expandCodeFor(SCEVHandle SH, const Type *Ty,
- BasicBlock::iterator IP) {
- setInsertionPoint(IP);
- return expandCodeFor(SH, Ty);
+ /// clearInsertPoint - Clear the current insertion point. This is useful
+ /// if the instruction that had been serving as the insertion point may
+ /// have been deleted.
+ void clearInsertPoint() {
+ Builder.ClearInsertionPoint();
}
- /// InsertCastOfTo - Insert a cast of V to the specified type, doing what
- /// we can to share the casts.
- Value *InsertCastOfTo(Instruction::CastOps opcode, Value *V,
- const Type *Ty);
+ private:
+ LLVMContext &getContext() const { return SE.getContext(); }
+
+ /// InsertBinop - Insert the specified binary operator, doing a small amount
+ /// of work to avoid inserting an obviously redundant operation.
+ Value *InsertBinop(Instruction::BinaryOps Opcode, Value *LHS, Value *RHS);
/// InsertNoopCastOfTo - Insert a cast of V to the specified type,
- /// which must be possible with a noop cast.
+ /// which must be possible with a noop cast, doing what we can to
+ /// share the casts.
Value *InsertNoopCastOfTo(Value *V, const Type *Ty);
- /// InsertBinop - Insert the specified binary operator, doing a small amount
- /// of work to avoid inserting an obviously redundant operation.
- static Value *InsertBinop(Instruction::BinaryOps Opcode, Value *LHS,
- Value *RHS, BasicBlock::iterator InsertPt);
+ /// expandAddToGEP - Expand a SCEVAddExpr with a pointer type into a GEP
+ /// instead of using ptrtoint+arithmetic+inttoptr.
+ Value *expandAddToGEP(const SCEV *const *op_begin,
+ const SCEV *const *op_end,
+ const PointerType *PTy, const Type *Ty, Value *V);
- private:
Value *expand(const SCEV *S);
+ /// expandCodeFor - Insert code to directly compute the specified SCEV
+ /// expression into the program. The inserted code is inserted into the
+ /// SCEVExpander's current insertion point. If a type is specified, the
+ /// result will be expanded to have that type, with a cast if necessary.
+ Value *expandCodeFor(const SCEV *SH, const Type *Ty = 0);
+
+ /// isInsertedInstruction - Return true if the specified instruction was
+ /// inserted by the code rewriter. If so, the client should not modify the
+ /// instruction.
+ bool isInsertedInstruction(Instruction *I) const {
+ return InsertedValues.count(I);
+ }
+
Value *visitConstant(const SCEVConstant *S) {
return S->getValue();
}
Value *visitUnknown(const SCEVUnknown *S) {
return S->getValue();
}
+
+ void rememberInstruction(Value *I);
+
+ void restoreInsertPoint(BasicBlock *BB, BasicBlock::iterator I);
+
+ Value *expandAddRecExprLiterally(const SCEVAddRecExpr *);
+ PHINode *getAddRecExprPHILiterally(const SCEVAddRecExpr *Normalized,
+ const Loop *L,
+ const Type *ExpandTy,
+ const Type *IntTy);
};
}
#endif
-