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.h"
20 #include "llvm/CodeGen/SelectionDAGNodes.h"
31 class MachineModuleInfo;
32 class MachineFunction;
33 class MachineConstantPoolValue;
35 /// SelectionDAG class - This is used to represent a portion of an LLVM function
36 /// in a low-level Data Dependence DAG representation suitable for instruction
37 /// selection. This DAG is constructed as the first step of instruction
38 /// selection in order to allow implementation of machine specific optimizations
39 /// and code simplifications.
41 /// The representation used by the SelectionDAG is a target-independent
42 /// representation, which has some similarities to the GCC RTL representation,
43 /// but is significantly more simple, powerful, and is a graph form instead of a
49 MachineModuleInfo *MMI;
51 /// Root - The root of the entire DAG. EntryNode - The starting token.
52 SDOperand Root, EntryNode;
54 /// AllNodes - A linked list of nodes in the current DAG.
55 ilist<SDNode> AllNodes;
57 /// CSEMap - This structure is used to memoize nodes, automatically performing
58 /// CSE with existing nodes with a duplicate is requested.
59 FoldingSet<SDNode> CSEMap;
62 SelectionDAG(TargetLowering &tli, MachineFunction &mf, MachineModuleInfo *mmi)
63 : TLI(tli), MF(mf), MMI(mmi) {
64 EntryNode = Root = getNode(ISD::EntryToken, MVT::Other);
68 MachineFunction &getMachineFunction() const { return MF; }
69 const TargetMachine &getTarget() const;
70 TargetLowering &getTargetLoweringInfo() const { return TLI; }
71 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
73 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
78 std::map<const SDNode *, std::string> NodeGraphAttrs;
81 /// clearGraphAttrs - Clear all previously defined node graph attributes.
82 /// Intended to be used from a debugging tool (eg. gdb).
83 void clearGraphAttrs();
85 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
87 void setGraphAttrs(const SDNode *N, const char *Attrs);
89 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
90 /// Used from getNodeAttributes.
91 const std::string getGraphAttrs(const SDNode *N) const;
93 /// setGraphColor - Convenience for setting node color attribute.
95 void setGraphColor(const SDNode *N, const char *Color);
97 typedef ilist<SDNode>::const_iterator allnodes_const_iterator;
98 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
99 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
100 typedef ilist<SDNode>::iterator allnodes_iterator;
101 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
102 allnodes_iterator allnodes_end() { return AllNodes.end(); }
104 /// getRoot - Return the root tag of the SelectionDAG.
106 const SDOperand &getRoot() const { return Root; }
108 /// getEntryNode - Return the token chain corresponding to the entry of the
110 const SDOperand &getEntryNode() const { return EntryNode; }
112 /// setRoot - Set the current root tag of the SelectionDAG.
114 const SDOperand &setRoot(SDOperand N) { return Root = N; }
116 /// Combine - This iterates over the nodes in the SelectionDAG, folding
117 /// certain types of nodes together, or eliminating superfluous nodes. When
118 /// the AfterLegalize argument is set to 'true', Combine takes care not to
119 /// generate any nodes that will be illegal on the target.
120 void Combine(bool AfterLegalize, AliasAnalysis &AA);
122 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
123 /// only uses types natively supported by the target.
125 /// Note that this is an involved process that may invalidate pointers into
127 void LegalizeTypes();
129 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
130 /// compatible with the target instruction selector, as indicated by the
131 /// TargetLowering object.
133 /// Note that this is an involved process that may invalidate pointers into
137 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
139 void RemoveDeadNodes();
141 /// DeleteNode - Remove the specified node from the system. This node must
142 /// have no referrers.
143 void DeleteNode(SDNode *N);
145 /// getVTList - Return an SDVTList that represents the list of values
147 SDVTList getVTList(MVT VT);
148 SDVTList getVTList(MVT VT1, MVT VT2);
149 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
150 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
152 /// getNodeValueTypes - These are obsolete, use getVTList instead.
153 const MVT *getNodeValueTypes(MVT VT) {
154 return getVTList(VT).VTs;
156 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
157 return getVTList(VT1, VT2).VTs;
159 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
160 return getVTList(VT1, VT2, VT3).VTs;
162 const MVT *getNodeValueTypes(std::vector<MVT> &vtList) {
163 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
167 //===--------------------------------------------------------------------===//
168 // Node creation methods.
170 SDOperand getString(const std::string &Val);
171 SDOperand getConstant(uint64_t Val, MVT VT, bool isTarget = false);
172 SDOperand getConstant(const APInt &Val, MVT VT, bool isTarget = false);
173 SDOperand getIntPtrConstant(uint64_t Val, bool isTarget = false);
174 SDOperand getTargetConstant(uint64_t Val, MVT VT) {
175 return getConstant(Val, VT, true);
177 SDOperand getTargetConstant(const APInt &Val, MVT VT) {
178 return getConstant(Val, VT, true);
180 SDOperand getConstantFP(double Val, MVT VT, bool isTarget = false);
181 SDOperand getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
182 SDOperand getTargetConstantFP(double Val, MVT VT) {
183 return getConstantFP(Val, VT, true);
185 SDOperand getTargetConstantFP(const APFloat& Val, MVT VT) {
186 return getConstantFP(Val, VT, true);
188 SDOperand getGlobalAddress(const GlobalValue *GV, MVT VT,
189 int offset = 0, bool isTargetGA = false);
190 SDOperand getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
192 return getGlobalAddress(GV, VT, offset, true);
194 SDOperand getFrameIndex(int FI, MVT VT, bool isTarget = false);
195 SDOperand getTargetFrameIndex(int FI, MVT VT) {
196 return getFrameIndex(FI, VT, true);
198 SDOperand getJumpTable(int JTI, MVT VT, bool isTarget = false);
199 SDOperand getTargetJumpTable(int JTI, MVT VT) {
200 return getJumpTable(JTI, VT, true);
202 SDOperand getConstantPool(Constant *C, MVT VT,
203 unsigned Align = 0, int Offs = 0, bool isT=false);
204 SDOperand getTargetConstantPool(Constant *C, MVT VT,
205 unsigned Align = 0, int Offset = 0) {
206 return getConstantPool(C, VT, Align, Offset, true);
208 SDOperand getConstantPool(MachineConstantPoolValue *C, MVT VT,
209 unsigned Align = 0, int Offs = 0, bool isT=false);
210 SDOperand getTargetConstantPool(MachineConstantPoolValue *C,
211 MVT VT, unsigned Align = 0,
213 return getConstantPool(C, VT, Align, Offset, true);
215 SDOperand getBasicBlock(MachineBasicBlock *MBB);
216 SDOperand getExternalSymbol(const char *Sym, MVT VT);
217 SDOperand getTargetExternalSymbol(const char *Sym, MVT VT);
218 SDOperand getArgFlags(ISD::ArgFlagsTy Flags);
219 SDOperand getValueType(MVT);
220 SDOperand getRegister(unsigned Reg, MVT VT);
222 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N) {
223 return getNode(ISD::CopyToReg, MVT::Other, Chain,
224 getRegister(Reg, N.getValueType()), N);
227 // This version of the getCopyToReg method takes an extra operand, which
228 // indicates that there is potentially an incoming flag value (if Flag is not
229 // null) and that there should be a flag result.
230 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N,
232 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
233 SDOperand Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
234 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
237 // Similar to last getCopyToReg() except parameter Reg is a SDOperand
238 SDOperand getCopyToReg(SDOperand Chain, SDOperand Reg, SDOperand N,
240 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
241 SDOperand Ops[] = { Chain, Reg, N, Flag };
242 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
245 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT) {
246 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
247 SDOperand Ops[] = { Chain, getRegister(Reg, VT) };
248 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
251 // This version of the getCopyFromReg method takes an extra operand, which
252 // indicates that there is potentially an incoming flag value (if Flag is not
253 // null) and that there should be a flag result.
254 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT,
256 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
257 SDOperand Ops[] = { Chain, getRegister(Reg, VT), Flag };
258 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.Val ? 3 : 2);
261 SDOperand getCondCode(ISD::CondCode Cond);
263 /// getZeroExtendInReg - Return the expression required to zero extend the Op
264 /// value assuming it was the smaller SrcTy value.
265 SDOperand getZeroExtendInReg(SDOperand Op, MVT SrcTy);
267 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
268 /// a flag result (to ensure it's not CSE'd).
269 SDOperand getCALLSEQ_START(SDOperand Chain, SDOperand Op) {
270 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
271 SDOperand Ops[] = { Chain, Op };
272 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
275 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
276 /// flag result (to ensure it's not CSE'd).
277 SDOperand getCALLSEQ_END(SDOperand Chain, SDOperand Op1, SDOperand Op2,
279 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
280 SmallVector<SDOperand, 4> Ops;
281 Ops.push_back(Chain);
284 Ops.push_back(InFlag);
285 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
286 (unsigned)Ops.size() - (InFlag.Val == 0 ? 1 : 0));
289 /// getNode - Gets or creates the specified node.
291 SDOperand getNode(unsigned Opcode, MVT VT);
292 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N);
293 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N1, SDOperand N2);
294 SDOperand getNode(unsigned Opcode, MVT VT,
295 SDOperand N1, SDOperand N2, SDOperand N3);
296 SDOperand getNode(unsigned Opcode, MVT VT,
297 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
298 SDOperand getNode(unsigned Opcode, MVT VT,
299 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
301 SDOperand getNode(unsigned Opcode, MVT VT, SDOperandPtr Ops, unsigned NumOps);
302 SDOperand getNode(unsigned Opcode, std::vector<MVT> &ResultTys,
303 SDOperandPtr Ops, unsigned NumOps);
304 SDOperand getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
305 SDOperandPtr Ops, unsigned NumOps);
306 SDOperand getNode(unsigned Opcode, SDVTList VTs);
307 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N);
308 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N1, SDOperand N2);
309 SDOperand getNode(unsigned Opcode, SDVTList VTs,
310 SDOperand N1, SDOperand N2, SDOperand N3);
311 SDOperand getNode(unsigned Opcode, SDVTList VTs,
312 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
313 SDOperand getNode(unsigned Opcode, SDVTList VTs,
314 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
316 SDOperand getNode(unsigned Opcode, SDVTList VTs,
317 SDOperandPtr Ops, unsigned NumOps);
319 SDOperand getMemcpy(SDOperand Chain, SDOperand Dst, SDOperand Src,
320 SDOperand Size, unsigned Align,
322 const Value *DstSV, uint64_t DstSVOff,
323 const Value *SrcSV, uint64_t SrcSVOff);
325 SDOperand getMemmove(SDOperand Chain, SDOperand Dst, SDOperand Src,
326 SDOperand Size, unsigned Align,
327 const Value *DstSV, uint64_t DstOSVff,
328 const Value *SrcSV, uint64_t SrcSVOff);
330 SDOperand getMemset(SDOperand Chain, SDOperand Dst, SDOperand Src,
331 SDOperand Size, unsigned Align,
332 const Value *DstSV, uint64_t DstSVOff);
334 /// getSetCC - Helper function to make it easier to build SetCC's if you just
335 /// have an ISD::CondCode instead of an SDOperand.
337 SDOperand getSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
338 ISD::CondCode Cond) {
339 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
342 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
343 /// if you just have an ISD::CondCode instead of an SDOperand.
345 SDOperand getVSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
346 ISD::CondCode Cond) {
347 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
350 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
351 /// just have an ISD::CondCode instead of an SDOperand.
353 SDOperand getSelectCC(SDOperand LHS, SDOperand RHS,
354 SDOperand True, SDOperand False, ISD::CondCode Cond) {
355 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
359 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
360 /// and a source value as input.
361 SDOperand getVAArg(MVT VT, SDOperand Chain, SDOperand Ptr,
364 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
366 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
367 SDOperand Cmp, SDOperand Swp, MVT VT);
369 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
371 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
372 SDOperand Val, MVT VT);
374 /// getLoad - Loads are not normal binary operators: their result type is not
375 /// determined by their operands, and they produce a value AND a token chain.
377 SDOperand getLoad(MVT VT, SDOperand Chain, SDOperand Ptr,
378 const Value *SV, int SVOffset, bool isVolatile=false,
379 unsigned Alignment=0);
380 SDOperand getExtLoad(ISD::LoadExtType ExtType, MVT VT,
381 SDOperand Chain, SDOperand Ptr, const Value *SV,
382 int SVOffset, MVT EVT, bool isVolatile=false,
383 unsigned Alignment=0);
384 SDOperand getIndexedLoad(SDOperand OrigLoad, SDOperand Base,
385 SDOperand Offset, ISD::MemIndexedMode AM);
386 SDOperand getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
387 MVT VT, SDOperand Chain,
388 SDOperand Ptr, SDOperand Offset,
389 const Value *SV, int SVOffset, MVT EVT,
390 bool isVolatile=false, unsigned Alignment=0);
392 /// getStore - Helper function to build ISD::STORE nodes.
394 SDOperand getStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
395 const Value *SV, int SVOffset, bool isVolatile=false,
396 unsigned Alignment=0);
397 SDOperand getTruncStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
398 const Value *SV, int SVOffset, MVT TVT,
399 bool isVolatile=false, unsigned Alignment=0);
400 SDOperand getIndexedStore(SDOperand OrigStoe, SDOperand Base,
401 SDOperand Offset, ISD::MemIndexedMode AM);
403 // getSrcValue - Construct a node to track a Value* through the backend.
404 SDOperand getSrcValue(const Value *v);
406 // getMemOperand - Construct a node to track a memory reference
407 // through the backend.
408 SDOperand getMemOperand(const MachineMemOperand &MO);
410 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
411 /// specified operands. If the resultant node already exists in the DAG,
412 /// this does not modify the specified node, instead it returns the node that
413 /// already exists. If the resultant node does not exist in the DAG, the
414 /// input node is returned. As a degenerate case, if you specify the same
415 /// input operands as the node already has, the input node is returned.
416 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op);
417 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2);
418 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
420 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
421 SDOperand Op3, SDOperand Op4);
422 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
423 SDOperand Op3, SDOperand Op4, SDOperand Op5);
424 SDOperand UpdateNodeOperands(SDOperand N, SDOperandPtr Ops, unsigned NumOps);
426 /// SelectNodeTo - These are used for target selectors to *mutate* the
427 /// specified node to have the specified return type, Target opcode, and
428 /// operands. Note that target opcodes are stored as
429 /// ISD::BUILTIN_OP_END+TargetOpcode in the node opcode field. The 0th value
430 /// of the resultant node is returned.
431 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
432 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDOperand Op1);
433 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
434 SDOperand Op1, SDOperand Op2);
435 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
436 SDOperand Op1, SDOperand Op2, SDOperand Op3);
437 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
438 SDOperandPtr Ops, unsigned NumOps);
439 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
440 MVT VT2, SDOperand Op1, SDOperand Op2);
441 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
442 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
445 /// getTargetNode - These are used for target selectors to create a new node
446 /// with specified return type(s), target opcode, and operands.
448 /// Note that getTargetNode returns the resultant node. If there is already a
449 /// node of the specified opcode and operands, it returns that node instead of
451 SDNode *getTargetNode(unsigned Opcode, MVT VT);
452 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1);
453 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1, SDOperand Op2);
454 SDNode *getTargetNode(unsigned Opcode, MVT VT,
455 SDOperand Op1, SDOperand Op2, SDOperand Op3);
456 SDNode *getTargetNode(unsigned Opcode, MVT VT,
457 SDOperandPtr Ops, unsigned NumOps);
458 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
459 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDOperand Op1);
460 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
461 MVT VT2, SDOperand Op1, SDOperand Op2);
462 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
463 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
464 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
465 SDOperandPtr Ops, unsigned NumOps);
466 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
467 SDOperand Op1, SDOperand Op2);
468 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
469 SDOperand Op1, SDOperand Op2, SDOperand Op3);
470 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
471 SDOperandPtr Ops, unsigned NumOps);
472 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
473 SDOperandPtr Ops, unsigned NumOps);
474 SDNode *getTargetNode(unsigned Opcode, std::vector<MVT> &ResultTys,
475 SDOperandPtr Ops, unsigned NumOps);
477 /// getNodeIfExists - Get the specified node if it's already available, or
478 /// else return NULL.
479 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
480 SDOperandPtr Ops, unsigned NumOps);
482 /// DAGUpdateListener - Clients of various APIs that cause global effects on
483 /// the DAG can optionally implement this interface. This allows the clients
484 /// to handle the various sorts of updates that happen.
485 class DAGUpdateListener {
487 virtual ~DAGUpdateListener();
488 virtual void NodeDeleted(SDNode *N) = 0;
489 virtual void NodeUpdated(SDNode *N) = 0;
492 /// RemoveDeadNode - Remove the specified node from the system. If any of its
493 /// operands then becomes dead, remove them as well. Inform UpdateListener
494 /// for each node deleted.
495 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
497 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
498 /// This can cause recursive merging of nodes in the DAG. Use the first
499 /// version if 'From' is known to have a single result, use the second
500 /// if you have two nodes with identical results, use the third otherwise.
502 /// These methods all take an optional UpdateListener, which (if not null) is
503 /// informed about nodes that are deleted and modified due to recursive
504 /// changes in the dag.
506 void ReplaceAllUsesWith(SDOperand From, SDOperand Op,
507 DAGUpdateListener *UpdateListener = 0);
508 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
509 DAGUpdateListener *UpdateListener = 0);
510 void ReplaceAllUsesWith(SDNode *From, SDOperandPtr To,
511 DAGUpdateListener *UpdateListener = 0);
513 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
514 /// uses of other values produced by From.Val alone.
515 void ReplaceAllUsesOfValueWith(SDOperand From, SDOperand To,
516 DAGUpdateListener *UpdateListener = 0);
518 /// AssignNodeIds - Assign a unique node id for each node in the DAG based on
519 /// their allnodes order. It returns the maximum id.
520 unsigned AssignNodeIds();
522 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
523 /// based on their topological order. It returns the maximum id and a vector
524 /// of the SDNodes* in assigned order by reference.
525 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
527 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
529 static bool isCommutativeBinOp(unsigned Opcode) {
530 // FIXME: This should get its info from the td file, so that we can include
545 case ISD::ADDE: return true;
546 default: return false;
552 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
553 /// specified value type.
554 SDOperand CreateStackTemporary(MVT VT);
556 /// FoldSetCC - Constant fold a setcc to true or false.
557 SDOperand FoldSetCC(MVT VT, SDOperand N1,
558 SDOperand N2, ISD::CondCode Cond);
560 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
561 /// use this predicate to simplify operations downstream.
562 bool SignBitIsZero(SDOperand Op, unsigned Depth = 0) const;
564 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
565 /// use this predicate to simplify operations downstream. Op and Mask are
566 /// known to be the same type.
567 bool MaskedValueIsZero(SDOperand Op, const APInt &Mask, unsigned Depth = 0)
570 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
571 /// known to be either zero or one and return them in the KnownZero/KnownOne
572 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
573 /// processing. Targets can implement the computeMaskedBitsForTargetNode
574 /// method in the TargetLowering class to allow target nodes to be understood.
575 void ComputeMaskedBits(SDOperand Op, const APInt &Mask, APInt &KnownZero,
576 APInt &KnownOne, unsigned Depth = 0) const;
578 /// ComputeNumSignBits - Return the number of times the sign bit of the
579 /// register is replicated into the other bits. We know that at least 1 bit
580 /// is always equal to the sign bit (itself), but other cases can give us
581 /// information. For example, immediately after an "SRA X, 2", we know that
582 /// the top 3 bits are all equal to each other, so we return 3. Targets can
583 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
584 /// class to allow target nodes to be understood.
585 unsigned ComputeNumSignBits(SDOperand Op, unsigned Depth = 0) const;
587 /// isVerifiedDebugInfoDesc - Returns true if the specified SDOperand has
588 /// been verified as a debug information descriptor.
589 bool isVerifiedDebugInfoDesc(SDOperand Op) const;
591 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
592 /// element of the result of the vector shuffle.
593 SDOperand getShuffleScalarElt(const SDNode *N, unsigned Idx);
596 void RemoveNodeFromCSEMaps(SDNode *N);
597 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
598 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op, void *&InsertPos);
599 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op1, SDOperand Op2,
601 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperandPtr Ops, unsigned NumOps,
604 void DeleteNodeNotInCSEMaps(SDNode *N);
606 // List of non-single value types.
607 std::list<std::vector<MVT> > VTList;
609 // Maps to auto-CSE operations.
610 std::vector<CondCodeSDNode*> CondCodeNodes;
612 std::vector<SDNode*> ValueTypeNodes;
613 std::map<MVT, SDNode*> ExtendedValueTypeNodes;
614 std::map<std::string, SDNode*> ExternalSymbols;
615 std::map<std::string, SDNode*> TargetExternalSymbols;
616 std::map<std::string, StringSDNode*> StringNodes;
619 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
620 typedef SelectionDAG::allnodes_iterator nodes_iterator;
621 static nodes_iterator nodes_begin(SelectionDAG *G) {
622 return G->allnodes_begin();
624 static nodes_iterator nodes_end(SelectionDAG *G) {
625 return G->allnodes_end();
629 } // end namespace llvm