1 //===-- llvm/CodeGen/SelectionDAG.h - InstSelection DAG ---------*- C++ -*-===//
3 // The LLVM Compiler Infrastructure
5 // This file is distributed under the University of Illinois Open Source
6 // License. See LICENSE.TXT for details.
8 //===----------------------------------------------------------------------===//
10 // This file declares the SelectionDAG class, and transitively defines the
11 // SDNode class and subclasses.
13 //===----------------------------------------------------------------------===//
15 #ifndef LLVM_CODEGEN_SELECTIONDAG_H
16 #define LLVM_CODEGEN_SELECTIONDAG_H
18 #include "llvm/ADT/FoldingSet.h"
19 #include "llvm/ADT/ilist"
20 #include "llvm/CodeGen/SelectionDAGNodes.h"
32 class MachineModuleInfo;
33 class MachineFunction;
34 class MachineConstantPoolValue;
36 /// SelectionDAG class - This is used to represent a portion of an LLVM function
37 /// in a low-level Data Dependence DAG representation suitable for instruction
38 /// selection. This DAG is constructed as the first step of instruction
39 /// selection in order to allow implementation of machine specific optimizations
40 /// and code simplifications.
42 /// The representation used by the SelectionDAG is a target-independent
43 /// representation, which has some similarities to the GCC RTL representation,
44 /// but is significantly more simple, powerful, and is a graph form instead of a
50 MachineModuleInfo *MMI;
52 /// Root - The root of the entire DAG. EntryNode - The starting token.
53 SDOperand Root, EntryNode;
55 /// AllNodes - A linked list of nodes in the current DAG.
56 ilist<SDNode> AllNodes;
58 /// CSEMap - This structure is used to memoize nodes, automatically performing
59 /// CSE with existing nodes with a duplicate is requested.
60 FoldingSet<SDNode> CSEMap;
63 SelectionDAG(TargetLowering &tli, MachineFunction &mf, MachineModuleInfo *mmi)
64 : TLI(tli), MF(mf), MMI(mmi) {
65 EntryNode = Root = getNode(ISD::EntryToken, MVT::Other);
69 MachineFunction &getMachineFunction() const { return MF; }
70 const TargetMachine &getTarget() const;
71 TargetLowering &getTargetLoweringInfo() const { return TLI; }
72 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
74 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
79 std::map<const SDNode *, std::string> NodeGraphAttrs;
82 /// clearGraphAttrs - Clear all previously defined node graph attributes.
83 /// Intended to be used from a debugging tool (eg. gdb).
84 void clearGraphAttrs();
86 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
88 void setGraphAttrs(const SDNode *N, const char *Attrs);
90 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
91 /// Used from getNodeAttributes.
92 const std::string getGraphAttrs(const SDNode *N) const;
94 /// setGraphColor - Convenience for setting node color attribute.
96 void setGraphColor(const SDNode *N, const char *Color);
98 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
99 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
100 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
101 typedef ilist<SDNode>::iterator allnodes_iterator;
102 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
103 allnodes_iterator allnodes_end() { return AllNodes.end(); }
105 /// getRoot - Return the root tag of the SelectionDAG.
107 const SDOperand &getRoot() const { return Root; }
109 /// getEntryNode - Return the token chain corresponding to the entry of the
111 const SDOperand &getEntryNode() const { return EntryNode; }
113 /// setRoot - Set the current root tag of the SelectionDAG.
115 const SDOperand &setRoot(SDOperand N) { return Root = N; }
117 /// Combine - This iterates over the nodes in the SelectionDAG, folding
118 /// certain types of nodes together, or eliminating superfluous nodes. When
119 /// the AfterLegalize argument is set to 'true', Combine takes care not to
120 /// generate any nodes that will be illegal on the target.
121 void Combine(bool AfterLegalize, AliasAnalysis &AA);
123 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
124 /// only uses types natively supported by the target.
126 /// Note that this is an involved process that may invalidate pointers into
128 void LegalizeTypes();
130 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
131 /// compatible with the target instruction selector, as indicated by the
132 /// TargetLowering object.
134 /// Note that this is an involved process that may invalidate pointers into
138 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
140 void RemoveDeadNodes();
142 /// DeleteNode - Remove the specified node from the system. This node must
143 /// have no referrers.
144 void DeleteNode(SDNode *N);
146 /// getVTList - Return an SDVTList that represents the list of values
148 SDVTList getVTList(MVT::ValueType VT);
149 SDVTList getVTList(MVT::ValueType VT1, MVT::ValueType VT2);
150 SDVTList getVTList(MVT::ValueType VT1, MVT::ValueType VT2,MVT::ValueType VT3);
151 SDVTList getVTList(const MVT::ValueType *VTs, unsigned NumVTs);
153 /// getNodeValueTypes - These are obsolete, use getVTList instead.
154 const MVT::ValueType *getNodeValueTypes(MVT::ValueType VT) {
155 return getVTList(VT).VTs;
157 const MVT::ValueType *getNodeValueTypes(MVT::ValueType VT1,
158 MVT::ValueType VT2) {
159 return getVTList(VT1, VT2).VTs;
161 const MVT::ValueType *getNodeValueTypes(MVT::ValueType VT1,MVT::ValueType VT2,
162 MVT::ValueType VT3) {
163 return getVTList(VT1, VT2, VT3).VTs;
165 const MVT::ValueType *getNodeValueTypes(std::vector<MVT::ValueType> &VTList) {
166 return getVTList(&VTList[0], VTList.size()).VTs;
170 //===--------------------------------------------------------------------===//
171 // Node creation methods.
173 SDOperand getString(const std::string &Val);
174 SDOperand getConstant(uint64_t Val, MVT::ValueType VT, bool isTarget = false);
175 SDOperand getIntPtrConstant(uint64_t Val, bool isTarget = false);
176 SDOperand getTargetConstant(uint64_t Val, MVT::ValueType VT) {
177 return getConstant(Val, VT, true);
179 SDOperand getConstantFP(double Val, MVT::ValueType VT, bool isTarget = false);
180 SDOperand getConstantFP(const APFloat& Val, MVT::ValueType VT,
181 bool isTarget = false);
182 SDOperand getTargetConstantFP(double Val, MVT::ValueType VT) {
183 return getConstantFP(Val, VT, true);
185 SDOperand getTargetConstantFP(const APFloat& Val, MVT::ValueType VT) {
186 return getConstantFP(Val, VT, true);
188 SDOperand getGlobalAddress(const GlobalValue *GV, MVT::ValueType VT,
189 int offset = 0, bool isTargetGA = false);
190 SDOperand getTargetGlobalAddress(const GlobalValue *GV, MVT::ValueType VT,
192 return getGlobalAddress(GV, VT, offset, true);
194 SDOperand getFrameIndex(int FI, MVT::ValueType VT, bool isTarget = false);
195 SDOperand getTargetFrameIndex(int FI, MVT::ValueType VT) {
196 return getFrameIndex(FI, VT, true);
198 SDOperand getJumpTable(int JTI, MVT::ValueType VT, bool isTarget = false);
199 SDOperand getTargetJumpTable(int JTI, MVT::ValueType VT) {
200 return getJumpTable(JTI, VT, true);
202 SDOperand getConstantPool(Constant *C, MVT::ValueType VT,
203 unsigned Align = 0, int Offs = 0, bool isT=false);
204 SDOperand getTargetConstantPool(Constant *C, MVT::ValueType VT,
205 unsigned Align = 0, int Offset = 0) {
206 return getConstantPool(C, VT, Align, Offset, true);
208 SDOperand getConstantPool(MachineConstantPoolValue *C, MVT::ValueType VT,
209 unsigned Align = 0, int Offs = 0, bool isT=false);
210 SDOperand getTargetConstantPool(MachineConstantPoolValue *C,
211 MVT::ValueType VT, unsigned Align = 0,
213 return getConstantPool(C, VT, Align, Offset, true);
215 SDOperand getBasicBlock(MachineBasicBlock *MBB);
216 SDOperand getExternalSymbol(const char *Sym, MVT::ValueType VT);
217 SDOperand getTargetExternalSymbol(const char *Sym, MVT::ValueType VT);
218 SDOperand getValueType(MVT::ValueType);
219 SDOperand getRegister(unsigned Reg, MVT::ValueType VT);
221 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N) {
222 return getNode(ISD::CopyToReg, MVT::Other, Chain,
223 getRegister(Reg, N.getValueType()), N);
226 // This version of the getCopyToReg method takes an extra operand, which
227 // indicates that there is potentially an incoming flag value (if Flag is not
228 // null) and that there should be a flag result.
229 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N,
231 const MVT::ValueType *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
232 SDOperand Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
233 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
236 // Similar to last getCopyToReg() except parameter Reg is a SDOperand
237 SDOperand getCopyToReg(SDOperand Chain, SDOperand Reg, SDOperand N,
239 const MVT::ValueType *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
240 SDOperand Ops[] = { Chain, Reg, N, Flag };
241 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
244 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT::ValueType VT) {
245 const MVT::ValueType *VTs = getNodeValueTypes(VT, MVT::Other);
246 SDOperand Ops[] = { Chain, getRegister(Reg, VT) };
247 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
250 // This version of the getCopyFromReg method takes an extra operand, which
251 // indicates that there is potentially an incoming flag value (if Flag is not
252 // null) and that there should be a flag result.
253 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT::ValueType VT,
255 const MVT::ValueType *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
256 SDOperand Ops[] = { Chain, getRegister(Reg, VT), Flag };
257 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.Val ? 3 : 2);
260 SDOperand getCondCode(ISD::CondCode Cond);
262 /// getZeroExtendInReg - Return the expression required to zero extend the Op
263 /// value assuming it was the smaller SrcTy value.
264 SDOperand getZeroExtendInReg(SDOperand Op, MVT::ValueType SrcTy);
266 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
267 /// a flag result (to ensure it's not CSE'd).
268 SDOperand getCALLSEQ_START(SDOperand Chain, SDOperand Op) {
269 const MVT::ValueType *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
270 SDOperand Ops[] = { Chain, Op };
271 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
274 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
275 /// flag result (to ensure it's not CSE'd).
276 SDOperand getCALLSEQ_END(SDOperand Chain, SDOperand Op1, SDOperand Op2,
278 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
279 SmallVector<SDOperand, 4> Ops;
280 Ops.push_back(Chain);
283 Ops.push_back(InFlag);
284 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
285 Ops.size() - (InFlag.Val == 0 ? 1 : 0));
288 /// getNode - Gets or creates the specified node.
290 SDOperand getNode(unsigned Opcode, MVT::ValueType VT);
291 SDOperand getNode(unsigned Opcode, MVT::ValueType VT, SDOperand N);
292 SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
293 SDOperand N1, SDOperand N2);
294 SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
295 SDOperand N1, SDOperand N2, SDOperand N3);
296 SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
297 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
298 SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
299 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
301 SDOperand getNode(unsigned Opcode, MVT::ValueType VT,
302 const SDOperand *Ops, unsigned NumOps);
303 SDOperand getNode(unsigned Opcode, std::vector<MVT::ValueType> &ResultTys,
304 const SDOperand *Ops, unsigned NumOps);
305 SDOperand getNode(unsigned Opcode, const MVT::ValueType *VTs, unsigned NumVTs,
306 const SDOperand *Ops, unsigned NumOps);
307 SDOperand getNode(unsigned Opcode, SDVTList VTs);
308 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N);
309 SDOperand getNode(unsigned Opcode, SDVTList VTs,
310 SDOperand N1, SDOperand N2);
311 SDOperand getNode(unsigned Opcode, SDVTList VTs,
312 SDOperand N1, SDOperand N2, SDOperand N3);
313 SDOperand getNode(unsigned Opcode, SDVTList VTs,
314 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
315 SDOperand getNode(unsigned Opcode, SDVTList VTs,
316 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
318 SDOperand getNode(unsigned Opcode, SDVTList VTs,
319 const SDOperand *Ops, unsigned NumOps);
321 SDOperand getMemcpy(SDOperand Chain, SDOperand Dest, SDOperand Src,
322 SDOperand Size, SDOperand Align,
323 SDOperand AlwaysInline);
325 SDOperand getMemmove(SDOperand Chain, SDOperand Dest, SDOperand Src,
326 SDOperand Size, SDOperand Align,
327 SDOperand AlwaysInline);
329 SDOperand getMemset(SDOperand Chain, SDOperand Dest, SDOperand Src,
330 SDOperand Size, SDOperand Align,
331 SDOperand AlwaysInline);
333 /// getSetCC - Helper function to make it easier to build SetCC's if you just
334 /// have an ISD::CondCode instead of an SDOperand.
336 SDOperand getSetCC(MVT::ValueType VT, SDOperand LHS, SDOperand RHS,
337 ISD::CondCode Cond) {
338 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
341 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
342 /// just have an ISD::CondCode instead of an SDOperand.
344 SDOperand getSelectCC(SDOperand LHS, SDOperand RHS,
345 SDOperand True, SDOperand False, ISD::CondCode Cond) {
346 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
350 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
351 /// and a source value as input.
352 SDOperand getVAArg(MVT::ValueType VT, SDOperand Chain, SDOperand Ptr,
355 /// getLoad - Loads are not normal binary operators: their result type is not
356 /// determined by their operands, and they produce a value AND a token chain.
358 SDOperand getLoad(MVT::ValueType VT, SDOperand Chain, SDOperand Ptr,
359 const Value *SV, int SVOffset, bool isVolatile=false,
360 unsigned Alignment=0);
361 SDOperand getExtLoad(ISD::LoadExtType ExtType, MVT::ValueType VT,
362 SDOperand Chain, SDOperand Ptr, const Value *SV,
363 int SVOffset, MVT::ValueType EVT, bool isVolatile=false,
364 unsigned Alignment=0);
365 SDOperand getIndexedLoad(SDOperand OrigLoad, SDOperand Base,
366 SDOperand Offset, ISD::MemIndexedMode AM);
368 /// getStore - Helper function to build ISD::STORE nodes.
370 SDOperand getStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
371 const Value *SV, int SVOffset, bool isVolatile=false,
372 unsigned Alignment=0);
373 SDOperand getTruncStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
374 const Value *SV, int SVOffset, MVT::ValueType TVT,
375 bool isVolatile=false, unsigned Alignment=0);
376 SDOperand getIndexedStore(SDOperand OrigStoe, SDOperand Base,
377 SDOperand Offset, ISD::MemIndexedMode AM);
379 // getSrcValue - construct a node to track a Value* through the backend
380 SDOperand getSrcValue(const Value* I, int offset = 0);
382 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
383 /// specified operands. If the resultant node already exists in the DAG,
384 /// this does not modify the specified node, instead it returns the node that
385 /// already exists. If the resultant node does not exist in the DAG, the
386 /// input node is returned. As a degenerate case, if you specify the same
387 /// input operands as the node already has, the input node is returned.
388 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op);
389 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2);
390 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
392 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
393 SDOperand Op3, SDOperand Op4);
394 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
395 SDOperand Op3, SDOperand Op4, SDOperand Op5);
396 SDOperand UpdateNodeOperands(SDOperand N, SDOperand *Ops, unsigned NumOps);
398 /// SelectNodeTo - These are used for target selectors to *mutate* the
399 /// specified node to have the specified return type, Target opcode, and
400 /// operands. Note that target opcodes are stored as
401 /// ISD::BUILTIN_OP_END+TargetOpcode in the node opcode field. The 0th value
402 /// of the resultant node is returned.
403 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT);
404 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
406 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
407 SDOperand Op1, SDOperand Op2);
408 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
409 SDOperand Op1, SDOperand Op2, SDOperand Op3);
410 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT,
411 const SDOperand *Ops, unsigned NumOps);
412 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT1,
413 MVT::ValueType VT2, SDOperand Op1, SDOperand Op2);
414 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT::ValueType VT1,
415 MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
419 /// getTargetNode - These are used for target selectors to create a new node
420 /// with specified return type(s), target opcode, and operands.
422 /// Note that getTargetNode returns the resultant node. If there is already a
423 /// node of the specified opcode and operands, it returns that node instead of
425 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT);
426 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT,
428 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT,
429 SDOperand Op1, SDOperand Op2);
430 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT,
431 SDOperand Op1, SDOperand Op2, SDOperand Op3);
432 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT,
433 const SDOperand *Ops, unsigned NumOps);
434 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
436 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
437 MVT::ValueType VT2, SDOperand Op1);
438 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
439 MVT::ValueType VT2, SDOperand Op1, SDOperand Op2);
440 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
441 MVT::ValueType VT2, SDOperand Op1, SDOperand Op2,
443 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
445 const SDOperand *Ops, unsigned NumOps);
446 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
447 MVT::ValueType VT2, MVT::ValueType VT3,
448 SDOperand Op1, SDOperand Op2);
449 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
450 MVT::ValueType VT2, MVT::ValueType VT3,
451 SDOperand Op1, SDOperand Op2, SDOperand Op3);
452 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
453 MVT::ValueType VT2, MVT::ValueType VT3,
454 const SDOperand *Ops, unsigned NumOps);
455 SDNode *getTargetNode(unsigned Opcode, MVT::ValueType VT1,
456 MVT::ValueType VT2, MVT::ValueType VT3,
458 const SDOperand *Ops, unsigned NumOps);
459 SDNode *getTargetNode(unsigned Opcode, std::vector<MVT::ValueType> &ResultTys,
460 const SDOperand *Ops, unsigned NumOps);
462 /// DAGUpdateListener - Clients of various APIs that cause global effects on
463 /// the DAG can optionally implement this interface. This allows the clients
464 /// to handle the various sorts of updates that happen.
465 class DAGUpdateListener {
467 virtual ~DAGUpdateListener();
468 virtual void NodeDeleted(SDNode *N) = 0;
469 virtual void NodeUpdated(SDNode *N) = 0;
472 /// RemoveDeadNode - Remove the specified node from the system. If any of its
473 /// operands then becomes dead, remove them as well. Inform UpdateListener
474 /// for each node deleted.
475 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
477 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
478 /// This can cause recursive merging of nodes in the DAG. Use the first
479 /// version if 'From' is known to have a single result, use the second
480 /// if you have two nodes with identical results, use the third otherwise.
482 /// These methods all take an optional UpdateListener, which (if not null) is
483 /// informed about nodes that are deleted and modified due to recursive
484 /// changes in the dag.
486 void ReplaceAllUsesWith(SDOperand From, SDOperand Op,
487 DAGUpdateListener *UpdateListener = 0);
488 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
489 DAGUpdateListener *UpdateListener = 0);
490 void ReplaceAllUsesWith(SDNode *From, const SDOperand *To,
491 DAGUpdateListener *UpdateListener = 0);
493 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
494 /// uses of other values produced by From.Val alone.
495 void ReplaceAllUsesOfValueWith(SDOperand From, SDOperand To,
496 DAGUpdateListener *UpdateListener = 0);
498 /// AssignNodeIds - Assign a unique node id for each node in the DAG based on
499 /// their allnodes order. It returns the maximum id.
500 unsigned AssignNodeIds();
502 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
503 /// based on their topological order. It returns the maximum id and a vector
504 /// of the SDNodes* in assigned order by reference.
505 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
507 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
509 static bool isCommutativeBinOp(unsigned Opcode) {
510 // FIXME: This should get its info from the td file, so that we can include
525 case ISD::ADDE: return true;
526 default: return false;
532 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
533 /// specified value type.
534 SDOperand CreateStackTemporary(MVT::ValueType VT);
536 /// FoldSetCC - Constant fold a setcc to true or false.
537 SDOperand FoldSetCC(MVT::ValueType VT, SDOperand N1,
538 SDOperand N2, ISD::CondCode Cond);
540 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
541 /// use this predicate to simplify operations downstream. Op and Mask are
542 /// known to be the same type.
543 bool MaskedValueIsZero(SDOperand Op, uint64_t Mask, unsigned Depth = 0)
546 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
547 /// known to be either zero or one and return them in the KnownZero/KnownOne
548 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
549 /// processing. Targets can implement the computeMaskedBitsForTargetNode
550 /// method in the TargetLowering class to allow target nodes to be understood.
551 void ComputeMaskedBits(SDOperand Op, uint64_t Mask, uint64_t &KnownZero,
552 uint64_t &KnownOne, unsigned Depth = 0) const;
554 /// ComputeNumSignBits - Return the number of times the sign bit of the
555 /// register is replicated into the other bits. We know that at least 1 bit
556 /// is always equal to the sign bit (itself), but other cases can give us
557 /// information. For example, immediately after an "SRA X, 2", we know that
558 /// the top 3 bits are all equal to each other, so we return 3. Targets can
559 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
560 /// class to allow target nodes to be understood.
561 unsigned ComputeNumSignBits(SDOperand Op, unsigned Depth = 0) const;
563 /// isVerifiedDebugInfoDesc - Returns true if the specified SDOperand has
564 /// been verified as a debug information descriptor.
565 bool isVerifiedDebugInfoDesc(SDOperand Op) const;
568 void RemoveNodeFromCSEMaps(SDNode *N);
569 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
570 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op, void *&InsertPos);
571 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op1, SDOperand Op2,
573 SDNode *FindModifiedNodeSlot(SDNode *N, const SDOperand *Ops, unsigned NumOps,
576 void DeleteNodeNotInCSEMaps(SDNode *N);
578 // List of non-single value types.
579 std::list<std::vector<MVT::ValueType> > VTList;
581 // Maps to auto-CSE operations.
582 std::vector<CondCodeSDNode*> CondCodeNodes;
584 std::vector<SDNode*> ValueTypeNodes;
585 std::map<MVT::ValueType, SDNode*> ExtendedValueTypeNodes;
586 std::map<std::string, SDNode*> ExternalSymbols;
587 std::map<std::string, SDNode*> TargetExternalSymbols;
588 std::map<std::string, StringSDNode*> StringNodes;
591 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
592 typedef SelectionDAG::allnodes_iterator nodes_iterator;
593 static nodes_iterator nodes_begin(SelectionDAG *G) {
594 return G->allnodes_begin();
596 static nodes_iterator nodes_end(SelectionDAG *G) {
597 return G->allnodes_end();
601 } // end namespace llvm