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/StringMap.h"
20 #include "llvm/CodeGen/SelectionDAGNodes.h"
31 class MachineModuleInfo;
32 class MachineFunction;
33 class MachineConstantPoolValue;
34 class FunctionLoweringInfo;
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 FunctionLoweringInfo &FLI;
51 MachineModuleInfo *MMI;
53 /// Root - The root of the entire DAG. EntryNode - The starting token.
54 SDOperand Root, EntryNode;
56 /// AllNodes - A linked list of nodes in the current DAG.
57 alist<SDNode, LargestSDNode> &AllNodes;
59 /// CSEMap - This structure is used to memoize nodes, automatically performing
60 /// CSE with existing nodes with a duplicate is requested.
61 FoldingSet<SDNode> CSEMap;
64 SelectionDAG(TargetLowering &tli, MachineFunction &mf,
65 FunctionLoweringInfo &fli, MachineModuleInfo *mmi,
66 alist<SDNode, LargestSDNode> &NodePool)
67 : TLI(tli), MF(mf), FLI(fli), MMI(mmi), AllNodes(NodePool) {
68 EntryNode = Root = getNode(ISD::EntryToken, MVT::Other);
72 MachineFunction &getMachineFunction() const { return MF; }
73 const TargetMachine &getTarget() const;
74 TargetLowering &getTargetLoweringInfo() const { return TLI; }
75 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
76 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
78 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
83 std::map<const SDNode *, std::string> NodeGraphAttrs;
86 /// clearGraphAttrs - Clear all previously defined node graph attributes.
87 /// Intended to be used from a debugging tool (eg. gdb).
88 void clearGraphAttrs();
90 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
92 void setGraphAttrs(const SDNode *N, const char *Attrs);
94 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
95 /// Used from getNodeAttributes.
96 const std::string getGraphAttrs(const SDNode *N) const;
98 /// setGraphColor - Convenience for setting node color attribute.
100 void setGraphColor(const SDNode *N, const char *Color);
102 typedef alist<SDNode, LargestSDNode>::const_iterator allnodes_const_iterator;
103 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
104 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
105 typedef alist<SDNode, LargestSDNode>::iterator allnodes_iterator;
106 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
107 allnodes_iterator allnodes_end() { return AllNodes.end(); }
108 alist<SDNode, LargestSDNode>::size_type allnodes_size() const {
109 return AllNodes.size();
112 /// getRoot - Return the root tag of the SelectionDAG.
114 const SDOperand &getRoot() const { return Root; }
116 /// getEntryNode - Return the token chain corresponding to the entry of the
118 const SDOperand &getEntryNode() const { return EntryNode; }
120 /// setRoot - Set the current root tag of the SelectionDAG.
122 const SDOperand &setRoot(SDOperand N) { return Root = N; }
124 /// Combine - This iterates over the nodes in the SelectionDAG, folding
125 /// certain types of nodes together, or eliminating superfluous nodes. When
126 /// the AfterLegalize argument is set to 'true', Combine takes care not to
127 /// generate any nodes that will be illegal on the target.
128 void Combine(bool AfterLegalize, AliasAnalysis &AA);
130 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
131 /// only uses types natively supported by the target.
133 /// Note that this is an involved process that may invalidate pointers into
135 void LegalizeTypes();
137 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
138 /// compatible with the target instruction selector, as indicated by the
139 /// TargetLowering object.
141 /// Note that this is an involved process that may invalidate pointers into
145 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
147 void RemoveDeadNodes();
149 /// DeleteNode - Remove the specified node from the system. This node must
150 /// have no referrers.
151 void DeleteNode(SDNode *N);
153 /// getVTList - Return an SDVTList that represents the list of values
155 SDVTList getVTList(MVT VT);
156 SDVTList getVTList(MVT VT1, MVT VT2);
157 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
158 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
160 /// getNodeValueTypes - These are obsolete, use getVTList instead.
161 const MVT *getNodeValueTypes(MVT VT) {
162 return getVTList(VT).VTs;
164 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
165 return getVTList(VT1, VT2).VTs;
167 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
168 return getVTList(VT1, VT2, VT3).VTs;
170 const MVT *getNodeValueTypes(std::vector<MVT> &vtList) {
171 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
175 //===--------------------------------------------------------------------===//
176 // Node creation methods.
178 SDOperand getConstant(uint64_t Val, MVT VT, bool isTarget = false);
179 SDOperand getConstant(const APInt &Val, MVT VT, bool isTarget = false);
180 SDOperand getIntPtrConstant(uint64_t Val, bool isTarget = false);
181 SDOperand getTargetConstant(uint64_t Val, MVT VT) {
182 return getConstant(Val, VT, true);
184 SDOperand getTargetConstant(const APInt &Val, MVT VT) {
185 return getConstant(Val, VT, true);
187 SDOperand getConstantFP(double Val, MVT VT, bool isTarget = false);
188 SDOperand getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
189 SDOperand getTargetConstantFP(double Val, MVT VT) {
190 return getConstantFP(Val, VT, true);
192 SDOperand getTargetConstantFP(const APFloat& Val, MVT VT) {
193 return getConstantFP(Val, VT, true);
195 SDOperand getGlobalAddress(const GlobalValue *GV, MVT VT,
196 int offset = 0, bool isTargetGA = false);
197 SDOperand getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
199 return getGlobalAddress(GV, VT, offset, true);
201 SDOperand getFrameIndex(int FI, MVT VT, bool isTarget = false);
202 SDOperand getTargetFrameIndex(int FI, MVT VT) {
203 return getFrameIndex(FI, VT, true);
205 SDOperand getJumpTable(int JTI, MVT VT, bool isTarget = false);
206 SDOperand getTargetJumpTable(int JTI, MVT VT) {
207 return getJumpTable(JTI, VT, true);
209 SDOperand getConstantPool(Constant *C, MVT VT,
210 unsigned Align = 0, int Offs = 0, bool isT=false);
211 SDOperand getTargetConstantPool(Constant *C, MVT VT,
212 unsigned Align = 0, int Offset = 0) {
213 return getConstantPool(C, VT, Align, Offset, true);
215 SDOperand getConstantPool(MachineConstantPoolValue *C, MVT VT,
216 unsigned Align = 0, int Offs = 0, bool isT=false);
217 SDOperand getTargetConstantPool(MachineConstantPoolValue *C,
218 MVT VT, unsigned Align = 0,
220 return getConstantPool(C, VT, Align, Offset, true);
222 SDOperand getBasicBlock(MachineBasicBlock *MBB);
223 SDOperand getExternalSymbol(const char *Sym, MVT VT);
224 SDOperand getTargetExternalSymbol(const char *Sym, MVT VT);
225 SDOperand getArgFlags(ISD::ArgFlagsTy Flags);
226 SDOperand getValueType(MVT);
227 SDOperand getRegister(unsigned Reg, MVT VT);
228 SDOperand getDbgStopPoint(SDOperand Root, unsigned Line, unsigned Col,
229 const CompileUnitDesc *CU);
230 SDOperand getLabel(unsigned Opcode, SDOperand Root, unsigned LabelID);
232 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N) {
233 return getNode(ISD::CopyToReg, MVT::Other, Chain,
234 getRegister(Reg, N.getValueType()), N);
237 // This version of the getCopyToReg method takes an extra operand, which
238 // indicates that there is potentially an incoming flag value (if Flag is not
239 // null) and that there should be a flag result.
240 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N,
242 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
243 SDOperand Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
244 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
247 // Similar to last getCopyToReg() except parameter Reg is a SDOperand
248 SDOperand getCopyToReg(SDOperand Chain, SDOperand Reg, SDOperand N,
250 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
251 SDOperand Ops[] = { Chain, Reg, N, Flag };
252 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
255 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT) {
256 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
257 SDOperand Ops[] = { Chain, getRegister(Reg, VT) };
258 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
261 // This version of the getCopyFromReg method takes an extra operand, which
262 // indicates that there is potentially an incoming flag value (if Flag is not
263 // null) and that there should be a flag result.
264 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT,
266 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
267 SDOperand Ops[] = { Chain, getRegister(Reg, VT), Flag };
268 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.Val ? 3 : 2);
271 SDOperand getCondCode(ISD::CondCode Cond);
273 /// getZeroExtendInReg - Return the expression required to zero extend the Op
274 /// value assuming it was the smaller SrcTy value.
275 SDOperand getZeroExtendInReg(SDOperand Op, MVT SrcTy);
277 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
278 /// a flag result (to ensure it's not CSE'd).
279 SDOperand getCALLSEQ_START(SDOperand Chain, SDOperand Op) {
280 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
281 SDOperand Ops[] = { Chain, Op };
282 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
285 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
286 /// flag result (to ensure it's not CSE'd).
287 SDOperand getCALLSEQ_END(SDOperand Chain, SDOperand Op1, SDOperand Op2,
289 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
290 SmallVector<SDOperand, 4> Ops;
291 Ops.push_back(Chain);
294 Ops.push_back(InFlag);
295 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
296 (unsigned)Ops.size() - (InFlag.Val == 0 ? 1 : 0));
299 /// getNode - Gets or creates the specified node.
301 SDOperand getNode(unsigned Opcode, MVT VT);
302 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N);
303 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N1, SDOperand N2);
304 SDOperand getNode(unsigned Opcode, MVT VT,
305 SDOperand N1, SDOperand N2, SDOperand N3);
306 SDOperand getNode(unsigned Opcode, MVT VT,
307 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
308 SDOperand getNode(unsigned Opcode, MVT VT,
309 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
311 SDOperand getNode(unsigned Opcode, MVT VT,
312 const SDOperand *Ops, unsigned NumOps);
313 SDOperand getNode(unsigned Opcode, MVT VT,
314 const SDUse *Ops, unsigned NumOps);
315 SDOperand getNode(unsigned Opcode, std::vector<MVT> &ResultTys,
316 const SDOperand *Ops, unsigned NumOps);
317 SDOperand getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
318 const SDOperand *Ops, unsigned NumOps);
319 SDOperand getNode(unsigned Opcode, SDVTList VTs);
320 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N);
321 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N1, SDOperand N2);
322 SDOperand getNode(unsigned Opcode, SDVTList VTs,
323 SDOperand N1, SDOperand N2, SDOperand N3);
324 SDOperand getNode(unsigned Opcode, SDVTList VTs,
325 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
326 SDOperand getNode(unsigned Opcode, SDVTList VTs,
327 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
329 SDOperand getNode(unsigned Opcode, SDVTList VTs,
330 const SDOperand *Ops, unsigned NumOps);
332 SDOperand getMemcpy(SDOperand Chain, SDOperand Dst, SDOperand Src,
333 SDOperand Size, unsigned Align,
335 const Value *DstSV, uint64_t DstSVOff,
336 const Value *SrcSV, uint64_t SrcSVOff);
338 SDOperand getMemmove(SDOperand Chain, SDOperand Dst, SDOperand Src,
339 SDOperand Size, unsigned Align,
340 const Value *DstSV, uint64_t DstOSVff,
341 const Value *SrcSV, uint64_t SrcSVOff);
343 SDOperand getMemset(SDOperand Chain, SDOperand Dst, SDOperand Src,
344 SDOperand Size, unsigned Align,
345 const Value *DstSV, uint64_t DstSVOff);
347 /// getSetCC - Helper function to make it easier to build SetCC's if you just
348 /// have an ISD::CondCode instead of an SDOperand.
350 SDOperand getSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
351 ISD::CondCode Cond) {
352 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
355 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
356 /// if you just have an ISD::CondCode instead of an SDOperand.
358 SDOperand getVSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
359 ISD::CondCode Cond) {
360 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
363 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
364 /// just have an ISD::CondCode instead of an SDOperand.
366 SDOperand getSelectCC(SDOperand LHS, SDOperand RHS,
367 SDOperand True, SDOperand False, ISD::CondCode Cond) {
368 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
372 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
373 /// and a source value as input.
374 SDOperand getVAArg(MVT VT, SDOperand Chain, SDOperand Ptr,
377 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
379 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
380 SDOperand Cmp, SDOperand Swp, const Value* PtrVal,
381 unsigned Alignment=0);
383 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
385 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
386 SDOperand Val, const Value* PtrVal,
387 unsigned Alignment = 0);
389 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
390 /// Allowed to return something different (and simpler) if Simplify is true.
391 SDOperand getMergeValues(const SDOperand *Ops, unsigned NumOps,
392 bool Simplify = true);
394 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
395 /// Allowed to return something different (and simpler) if Simplify is true.
396 /// May be faster than the above version if VTs is known and NumOps is large.
397 SDOperand getMergeValues(SDVTList VTs, const SDOperand *Ops, unsigned NumOps,
398 bool Simplify = true) {
399 if (Simplify && NumOps == 1)
401 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
404 /// getLoad - Loads are not normal binary operators: their result type is not
405 /// determined by their operands, and they produce a value AND a token chain.
407 SDOperand getLoad(MVT VT, SDOperand Chain, SDOperand Ptr,
408 const Value *SV, int SVOffset, bool isVolatile=false,
409 unsigned Alignment=0);
410 SDOperand getExtLoad(ISD::LoadExtType ExtType, MVT VT,
411 SDOperand Chain, SDOperand Ptr, const Value *SV,
412 int SVOffset, MVT EVT, bool isVolatile=false,
413 unsigned Alignment=0);
414 SDOperand getIndexedLoad(SDOperand OrigLoad, SDOperand Base,
415 SDOperand Offset, ISD::MemIndexedMode AM);
416 SDOperand getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
417 MVT VT, SDOperand Chain,
418 SDOperand Ptr, SDOperand Offset,
419 const Value *SV, int SVOffset, MVT EVT,
420 bool isVolatile=false, unsigned Alignment=0);
422 /// getStore - Helper function to build ISD::STORE nodes.
424 SDOperand getStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
425 const Value *SV, int SVOffset, bool isVolatile=false,
426 unsigned Alignment=0);
427 SDOperand getTruncStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
428 const Value *SV, int SVOffset, MVT TVT,
429 bool isVolatile=false, unsigned Alignment=0);
430 SDOperand getIndexedStore(SDOperand OrigStoe, SDOperand Base,
431 SDOperand Offset, ISD::MemIndexedMode AM);
433 // getSrcValue - Construct a node to track a Value* through the backend.
434 SDOperand getSrcValue(const Value *v);
436 // getMemOperand - Construct a node to track a memory reference
437 // through the backend.
438 SDOperand getMemOperand(const MachineMemOperand &MO);
440 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
441 /// specified operands. If the resultant node already exists in the DAG,
442 /// this does not modify the specified node, instead it returns the node that
443 /// already exists. If the resultant node does not exist in the DAG, the
444 /// input node is returned. As a degenerate case, if you specify the same
445 /// input operands as the node already has, the input node is returned.
446 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op);
447 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2);
448 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
450 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
451 SDOperand Op3, SDOperand Op4);
452 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
453 SDOperand Op3, SDOperand Op4, SDOperand Op5);
454 SDOperand UpdateNodeOperands(SDOperand N,
455 const SDOperand *Ops, unsigned NumOps);
457 /// SelectNodeTo - These are used for target selectors to *mutate* the
458 /// specified node to have the specified return type, Target opcode, and
459 /// operands. Note that target opcodes are stored as
460 /// ISD::BUILTIN_OP_END+TargetOpcode in the node opcode field. The 0th value
461 /// of the resultant node is returned.
462 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
463 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDOperand Op1);
464 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
465 SDOperand Op1, SDOperand Op2);
466 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
467 SDOperand Op1, SDOperand Op2, SDOperand Op3);
468 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
469 const SDOperand *Ops, unsigned NumOps);
470 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
471 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
472 MVT VT2, const SDOperand *Ops, unsigned NumOps);
473 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
474 MVT VT2, MVT VT3, const SDOperand *Ops, unsigned NumOps);
475 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
476 MVT VT2, SDOperand Op1);
477 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
478 MVT VT2, SDOperand Op1, SDOperand Op2);
479 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
480 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
481 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
482 const SDOperand *Ops, unsigned NumOps);
485 /// getTargetNode - These are used for target selectors to create a new node
486 /// with specified return type(s), target opcode, and operands.
488 /// Note that getTargetNode returns the resultant node. If there is already a
489 /// node of the specified opcode and operands, it returns that node instead of
491 SDNode *getTargetNode(unsigned Opcode, MVT VT);
492 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1);
493 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1, SDOperand Op2);
494 SDNode *getTargetNode(unsigned Opcode, MVT VT,
495 SDOperand Op1, SDOperand Op2, SDOperand Op3);
496 SDNode *getTargetNode(unsigned Opcode, MVT VT,
497 const SDOperand *Ops, unsigned NumOps);
498 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
499 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDOperand Op1);
500 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
501 MVT VT2, SDOperand Op1, SDOperand Op2);
502 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
503 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
504 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
505 const SDOperand *Ops, unsigned NumOps);
506 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
507 SDOperand Op1, SDOperand Op2);
508 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
509 SDOperand Op1, SDOperand Op2, SDOperand Op3);
510 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
511 const SDOperand *Ops, unsigned NumOps);
512 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
513 const SDOperand *Ops, unsigned NumOps);
514 SDNode *getTargetNode(unsigned Opcode, std::vector<MVT> &ResultTys,
515 const SDOperand *Ops, unsigned NumOps);
517 /// getNodeIfExists - Get the specified node if it's already available, or
518 /// else return NULL.
519 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
520 const SDOperand *Ops, unsigned NumOps);
522 /// DAGUpdateListener - Clients of various APIs that cause global effects on
523 /// the DAG can optionally implement this interface. This allows the clients
524 /// to handle the various sorts of updates that happen.
525 class DAGUpdateListener {
527 virtual ~DAGUpdateListener();
529 /// NodeDeleted - The node N that was deleted and, if E is not null, an
530 /// equivalent node E that replaced it.
531 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
533 /// NodeUpdated - The node N that was updated.
534 virtual void NodeUpdated(SDNode *N) = 0;
537 /// RemoveDeadNode - Remove the specified node from the system. If any of its
538 /// operands then becomes dead, remove them as well. Inform UpdateListener
539 /// for each node deleted.
540 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
542 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
543 /// given list, and any nodes that become unreachable as a result.
544 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
545 DAGUpdateListener *UpdateListener = 0);
547 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
548 /// This can cause recursive merging of nodes in the DAG. Use the first
549 /// version if 'From' is known to have a single result, use the second
550 /// if you have two nodes with identical results, use the third otherwise.
552 /// These methods all take an optional UpdateListener, which (if not null) is
553 /// informed about nodes that are deleted and modified due to recursive
554 /// changes in the dag.
556 void ReplaceAllUsesWith(SDOperand From, SDOperand Op,
557 DAGUpdateListener *UpdateListener = 0);
558 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
559 DAGUpdateListener *UpdateListener = 0);
560 void ReplaceAllUsesWith(SDNode *From, const SDOperand *To,
561 DAGUpdateListener *UpdateListener = 0);
563 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
564 /// uses of other values produced by From.Val alone.
565 void ReplaceAllUsesOfValueWith(SDOperand From, SDOperand To,
566 DAGUpdateListener *UpdateListener = 0);
568 /// AssignNodeIds - Assign a unique node id for each node in the DAG based on
569 /// their allnodes order. It returns the maximum id.
570 unsigned AssignNodeIds();
572 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
573 /// based on their topological order. It returns the maximum id and a vector
574 /// of the SDNodes* in assigned order by reference.
575 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
577 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
579 static bool isCommutativeBinOp(unsigned Opcode) {
580 // FIXME: This should get its info from the td file, so that we can include
595 case ISD::ADDE: return true;
596 default: return false;
602 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
603 /// specified value type. If minAlign is specified, the slot size will have
604 /// at least that alignment.
605 SDOperand CreateStackTemporary(MVT VT, unsigned minAlign = 1);
607 /// FoldSetCC - Constant fold a setcc to true or false.
608 SDOperand FoldSetCC(MVT VT, SDOperand N1,
609 SDOperand N2, ISD::CondCode Cond);
611 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
612 /// use this predicate to simplify operations downstream.
613 bool SignBitIsZero(SDOperand Op, unsigned Depth = 0) const;
615 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
616 /// use this predicate to simplify operations downstream. Op and Mask are
617 /// known to be the same type.
618 bool MaskedValueIsZero(SDOperand Op, const APInt &Mask, unsigned Depth = 0)
621 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
622 /// known to be either zero or one and return them in the KnownZero/KnownOne
623 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
624 /// processing. Targets can implement the computeMaskedBitsForTargetNode
625 /// method in the TargetLowering class to allow target nodes to be understood.
626 void ComputeMaskedBits(SDOperand Op, const APInt &Mask, APInt &KnownZero,
627 APInt &KnownOne, unsigned Depth = 0) const;
629 /// ComputeNumSignBits - Return the number of times the sign bit of the
630 /// register is replicated into the other bits. We know that at least 1 bit
631 /// is always equal to the sign bit (itself), but other cases can give us
632 /// information. For example, immediately after an "SRA X, 2", we know that
633 /// the top 3 bits are all equal to each other, so we return 3. Targets can
634 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
635 /// class to allow target nodes to be understood.
636 unsigned ComputeNumSignBits(SDOperand Op, unsigned Depth = 0) const;
638 /// isVerifiedDebugInfoDesc - Returns true if the specified SDOperand has
639 /// been verified as a debug information descriptor.
640 bool isVerifiedDebugInfoDesc(SDOperand Op) const;
642 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
643 /// element of the result of the vector shuffle.
644 SDOperand getShuffleScalarElt(const SDNode *N, unsigned Idx);
647 inline alist_traits<SDNode, LargestSDNode>::AllocatorType &getAllocator();
648 void RemoveNodeFromCSEMaps(SDNode *N);
649 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
650 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op, void *&InsertPos);
651 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op1, SDOperand Op2,
653 SDNode *FindModifiedNodeSlot(SDNode *N, const SDOperand *Ops, unsigned NumOps,
656 void DeleteNodeNotInCSEMaps(SDNode *N);
658 // List of non-single value types.
659 std::list<std::vector<MVT> > VTList;
661 // Maps to auto-CSE operations.
662 std::vector<CondCodeSDNode*> CondCodeNodes;
664 std::vector<SDNode*> ValueTypeNodes;
665 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
666 StringMap<SDNode*> ExternalSymbols;
667 StringMap<SDNode*> TargetExternalSymbols;
670 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
671 typedef SelectionDAG::allnodes_iterator nodes_iterator;
672 static nodes_iterator nodes_begin(SelectionDAG *G) {
673 return G->allnodes_begin();
675 static nodes_iterator nodes_end(SelectionDAG *G) {
676 return G->allnodes_end();
680 } // end namespace llvm