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/ADT/ilist.h"
21 #include "llvm/CodeGen/SelectionDAGNodes.h"
32 class MachineModuleInfo;
33 class MachineFunction;
34 class MachineConstantPoolValue;
35 class FunctionLoweringInfo;
37 /// SelectionDAG class - This is used to represent a portion of an LLVM function
38 /// in a low-level Data Dependence DAG representation suitable for instruction
39 /// selection. This DAG is constructed as the first step of instruction
40 /// selection in order to allow implementation of machine specific optimizations
41 /// and code simplifications.
43 /// The representation used by the SelectionDAG is a target-independent
44 /// representation, which has some similarities to the GCC RTL representation,
45 /// but is significantly more simple, powerful, and is a graph form instead of a
51 FunctionLoweringInfo &FLI;
52 MachineModuleInfo *MMI;
54 /// Root - The root of the entire DAG. EntryNode - The starting token.
55 SDOperand Root, EntryNode;
57 /// AllNodes - A linked list of nodes in the current DAG.
58 ilist<SDNode> AllNodes;
60 /// CSEMap - This structure is used to memoize nodes, automatically performing
61 /// CSE with existing nodes with a duplicate is requested.
62 FoldingSet<SDNode> CSEMap;
65 SelectionDAG(TargetLowering &tli, MachineFunction &mf,
66 FunctionLoweringInfo &fli, MachineModuleInfo *mmi)
67 : TLI(tli), MF(mf), FLI(fli), MMI(mmi) {
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 ilist<SDNode>::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 ilist<SDNode>::iterator allnodes_iterator;
106 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
107 allnodes_iterator allnodes_end() { return AllNodes.end(); }
108 ilist<SDNode>::size_type allnodes_size() const { return AllNodes.size(); }
110 /// getRoot - Return the root tag of the SelectionDAG.
112 const SDOperand &getRoot() const { return Root; }
114 /// getEntryNode - Return the token chain corresponding to the entry of the
116 const SDOperand &getEntryNode() const { return EntryNode; }
118 /// setRoot - Set the current root tag of the SelectionDAG.
120 const SDOperand &setRoot(SDOperand N) { return Root = N; }
122 /// Combine - This iterates over the nodes in the SelectionDAG, folding
123 /// certain types of nodes together, or eliminating superfluous nodes. When
124 /// the AfterLegalize argument is set to 'true', Combine takes care not to
125 /// generate any nodes that will be illegal on the target.
126 void Combine(bool AfterLegalize, AliasAnalysis &AA);
128 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
129 /// only uses types natively supported by the target.
131 /// Note that this is an involved process that may invalidate pointers into
133 void LegalizeTypes();
135 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
136 /// compatible with the target instruction selector, as indicated by the
137 /// TargetLowering object.
139 /// Note that this is an involved process that may invalidate pointers into
143 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
145 void RemoveDeadNodes();
147 /// DeleteNode - Remove the specified node from the system. This node must
148 /// have no referrers.
149 void DeleteNode(SDNode *N);
151 /// getVTList - Return an SDVTList that represents the list of values
153 SDVTList getVTList(MVT VT);
154 SDVTList getVTList(MVT VT1, MVT VT2);
155 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
156 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
158 /// getNodeValueTypes - These are obsolete, use getVTList instead.
159 const MVT *getNodeValueTypes(MVT VT) {
160 return getVTList(VT).VTs;
162 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
163 return getVTList(VT1, VT2).VTs;
165 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
166 return getVTList(VT1, VT2, VT3).VTs;
168 const MVT *getNodeValueTypes(std::vector<MVT> &vtList) {
169 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
173 //===--------------------------------------------------------------------===//
174 // Node creation methods.
176 SDOperand getConstant(uint64_t Val, MVT VT, bool isTarget = false);
177 SDOperand getConstant(const APInt &Val, MVT VT, bool isTarget = false);
178 SDOperand getIntPtrConstant(uint64_t Val, bool isTarget = false);
179 SDOperand getTargetConstant(uint64_t Val, MVT VT) {
180 return getConstant(Val, VT, true);
182 SDOperand getTargetConstant(const APInt &Val, MVT VT) {
183 return getConstant(Val, VT, true);
185 SDOperand getConstantFP(double Val, MVT VT, bool isTarget = false);
186 SDOperand getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
187 SDOperand getTargetConstantFP(double Val, MVT VT) {
188 return getConstantFP(Val, VT, true);
190 SDOperand getTargetConstantFP(const APFloat& Val, MVT VT) {
191 return getConstantFP(Val, VT, true);
193 SDOperand getGlobalAddress(const GlobalValue *GV, MVT VT,
194 int offset = 0, bool isTargetGA = false);
195 SDOperand getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
197 return getGlobalAddress(GV, VT, offset, true);
199 SDOperand getFrameIndex(int FI, MVT VT, bool isTarget = false);
200 SDOperand getTargetFrameIndex(int FI, MVT VT) {
201 return getFrameIndex(FI, VT, true);
203 SDOperand getJumpTable(int JTI, MVT VT, bool isTarget = false);
204 SDOperand getTargetJumpTable(int JTI, MVT VT) {
205 return getJumpTable(JTI, VT, true);
207 SDOperand getConstantPool(Constant *C, MVT VT,
208 unsigned Align = 0, int Offs = 0, bool isT=false);
209 SDOperand getTargetConstantPool(Constant *C, MVT VT,
210 unsigned Align = 0, int Offset = 0) {
211 return getConstantPool(C, VT, Align, Offset, true);
213 SDOperand getConstantPool(MachineConstantPoolValue *C, MVT VT,
214 unsigned Align = 0, int Offs = 0, bool isT=false);
215 SDOperand getTargetConstantPool(MachineConstantPoolValue *C,
216 MVT VT, unsigned Align = 0,
218 return getConstantPool(C, VT, Align, Offset, true);
220 SDOperand getBasicBlock(MachineBasicBlock *MBB);
221 SDOperand getExternalSymbol(const char *Sym, MVT VT);
222 SDOperand getTargetExternalSymbol(const char *Sym, MVT VT);
223 SDOperand getArgFlags(ISD::ArgFlagsTy Flags);
224 SDOperand getValueType(MVT);
225 SDOperand getRegister(unsigned Reg, MVT VT);
226 SDOperand getDbgStopPoint(SDOperand Root, unsigned Line, unsigned Col,
227 const CompileUnitDesc *CU);
228 SDOperand getLabel(unsigned Opcode, SDOperand Root, unsigned LabelID);
230 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N) {
231 return getNode(ISD::CopyToReg, MVT::Other, Chain,
232 getRegister(Reg, N.getValueType()), N);
235 // This version of the getCopyToReg method takes an extra operand, which
236 // indicates that there is potentially an incoming flag value (if Flag is not
237 // null) and that there should be a flag result.
238 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N,
240 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
241 SDOperand Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
242 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
245 // Similar to last getCopyToReg() except parameter Reg is a SDOperand
246 SDOperand getCopyToReg(SDOperand Chain, SDOperand Reg, SDOperand N,
248 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
249 SDOperand Ops[] = { Chain, Reg, N, Flag };
250 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
253 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT) {
254 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
255 SDOperand Ops[] = { Chain, getRegister(Reg, VT) };
256 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
259 // This version of the getCopyFromReg method takes an extra operand, which
260 // indicates that there is potentially an incoming flag value (if Flag is not
261 // null) and that there should be a flag result.
262 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT,
264 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
265 SDOperand Ops[] = { Chain, getRegister(Reg, VT), Flag };
266 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.Val ? 3 : 2);
269 SDOperand getCondCode(ISD::CondCode Cond);
271 /// getZeroExtendInReg - Return the expression required to zero extend the Op
272 /// value assuming it was the smaller SrcTy value.
273 SDOperand getZeroExtendInReg(SDOperand Op, MVT SrcTy);
275 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
276 /// a flag result (to ensure it's not CSE'd).
277 SDOperand getCALLSEQ_START(SDOperand Chain, SDOperand Op) {
278 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
279 SDOperand Ops[] = { Chain, Op };
280 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
283 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
284 /// flag result (to ensure it's not CSE'd).
285 SDOperand getCALLSEQ_END(SDOperand Chain, SDOperand Op1, SDOperand Op2,
287 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
288 SmallVector<SDOperand, 4> Ops;
289 Ops.push_back(Chain);
292 Ops.push_back(InFlag);
293 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
294 (unsigned)Ops.size() - (InFlag.Val == 0 ? 1 : 0));
297 /// getNode - Gets or creates the specified node.
299 SDOperand getNode(unsigned Opcode, MVT VT);
300 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N);
301 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N1, SDOperand N2);
302 SDOperand getNode(unsigned Opcode, MVT VT,
303 SDOperand N1, SDOperand N2, SDOperand N3);
304 SDOperand getNode(unsigned Opcode, MVT VT,
305 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
306 SDOperand getNode(unsigned Opcode, MVT VT,
307 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
309 SDOperand getNode(unsigned Opcode, MVT VT,
310 const SDOperand *Ops, unsigned NumOps);
311 SDOperand getNode(unsigned Opcode, MVT VT,
312 const SDUse *Ops, unsigned NumOps);
313 SDOperand getNode(unsigned Opcode, std::vector<MVT> &ResultTys,
314 const SDOperand *Ops, unsigned NumOps);
315 SDOperand getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
316 const SDOperand *Ops, unsigned NumOps);
317 SDOperand getNode(unsigned Opcode, SDVTList VTs);
318 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N);
319 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N1, SDOperand N2);
320 SDOperand getNode(unsigned Opcode, SDVTList VTs,
321 SDOperand N1, SDOperand N2, SDOperand N3);
322 SDOperand getNode(unsigned Opcode, SDVTList VTs,
323 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
324 SDOperand getNode(unsigned Opcode, SDVTList VTs,
325 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
327 SDOperand getNode(unsigned Opcode, SDVTList VTs,
328 const SDOperand *Ops, unsigned NumOps);
330 SDOperand getMemcpy(SDOperand Chain, SDOperand Dst, SDOperand Src,
331 SDOperand Size, unsigned Align,
333 const Value *DstSV, uint64_t DstSVOff,
334 const Value *SrcSV, uint64_t SrcSVOff);
336 SDOperand getMemmove(SDOperand Chain, SDOperand Dst, SDOperand Src,
337 SDOperand Size, unsigned Align,
338 const Value *DstSV, uint64_t DstOSVff,
339 const Value *SrcSV, uint64_t SrcSVOff);
341 SDOperand getMemset(SDOperand Chain, SDOperand Dst, SDOperand Src,
342 SDOperand Size, unsigned Align,
343 const Value *DstSV, uint64_t DstSVOff);
345 /// getSetCC - Helper function to make it easier to build SetCC's if you just
346 /// have an ISD::CondCode instead of an SDOperand.
348 SDOperand getSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
349 ISD::CondCode Cond) {
350 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
353 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
354 /// if you just have an ISD::CondCode instead of an SDOperand.
356 SDOperand getVSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
357 ISD::CondCode Cond) {
358 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
361 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
362 /// just have an ISD::CondCode instead of an SDOperand.
364 SDOperand getSelectCC(SDOperand LHS, SDOperand RHS,
365 SDOperand True, SDOperand False, ISD::CondCode Cond) {
366 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
370 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
371 /// and a source value as input.
372 SDOperand getVAArg(MVT VT, SDOperand Chain, SDOperand Ptr,
375 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
377 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
378 SDOperand Cmp, SDOperand Swp, const Value* PtrVal,
379 unsigned Alignment=0);
381 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
383 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
384 SDOperand Val, const Value* PtrVal,
385 unsigned Alignment = 0);
387 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
388 /// Allowed to return something different (and simpler) if Simplify is true.
389 SDOperand getMergeValues(const SDOperand *Ops, unsigned NumOps,
390 bool Simplify = true);
392 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
393 /// Allowed to return something different (and simpler) if Simplify is true.
394 /// May be faster than the above version if VTs is known and NumOps is large.
395 SDOperand getMergeValues(SDVTList VTs, const SDOperand *Ops, unsigned NumOps,
396 bool Simplify = true) {
397 if (Simplify && NumOps == 1)
399 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
402 /// getLoad - Loads are not normal binary operators: their result type is not
403 /// determined by their operands, and they produce a value AND a token chain.
405 SDOperand getLoad(MVT VT, SDOperand Chain, SDOperand Ptr,
406 const Value *SV, int SVOffset, bool isVolatile=false,
407 unsigned Alignment=0);
408 SDOperand getExtLoad(ISD::LoadExtType ExtType, MVT VT,
409 SDOperand Chain, SDOperand Ptr, const Value *SV,
410 int SVOffset, MVT EVT, bool isVolatile=false,
411 unsigned Alignment=0);
412 SDOperand getIndexedLoad(SDOperand OrigLoad, SDOperand Base,
413 SDOperand Offset, ISD::MemIndexedMode AM);
414 SDOperand getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
415 MVT VT, SDOperand Chain,
416 SDOperand Ptr, SDOperand Offset,
417 const Value *SV, int SVOffset, MVT EVT,
418 bool isVolatile=false, unsigned Alignment=0);
420 /// getStore - Helper function to build ISD::STORE nodes.
422 SDOperand getStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
423 const Value *SV, int SVOffset, bool isVolatile=false,
424 unsigned Alignment=0);
425 SDOperand getTruncStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
426 const Value *SV, int SVOffset, MVT TVT,
427 bool isVolatile=false, unsigned Alignment=0);
428 SDOperand getIndexedStore(SDOperand OrigStoe, SDOperand Base,
429 SDOperand Offset, ISD::MemIndexedMode AM);
431 // getSrcValue - Construct a node to track a Value* through the backend.
432 SDOperand getSrcValue(const Value *v);
434 // getMemOperand - Construct a node to track a memory reference
435 // through the backend.
436 SDOperand getMemOperand(const MachineMemOperand &MO);
438 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
439 /// specified operands. If the resultant node already exists in the DAG,
440 /// this does not modify the specified node, instead it returns the node that
441 /// already exists. If the resultant node does not exist in the DAG, the
442 /// input node is returned. As a degenerate case, if you specify the same
443 /// input operands as the node already has, the input node is returned.
444 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op);
445 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2);
446 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
448 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
449 SDOperand Op3, SDOperand Op4);
450 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
451 SDOperand Op3, SDOperand Op4, SDOperand Op5);
452 SDOperand UpdateNodeOperands(SDOperand N,
453 const SDOperand *Ops, unsigned NumOps);
455 /// SelectNodeTo - These are used for target selectors to *mutate* the
456 /// specified node to have the specified return type, Target opcode, and
457 /// operands. Note that target opcodes are stored as
458 /// ISD::BUILTIN_OP_END+TargetOpcode in the node opcode field. The 0th value
459 /// of the resultant node is returned.
460 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
461 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDOperand Op1);
462 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
463 SDOperand Op1, SDOperand Op2);
464 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
465 SDOperand Op1, SDOperand Op2, SDOperand Op3);
466 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
467 const SDOperand *Ops, unsigned NumOps);
468 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
469 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
470 MVT VT2, const SDOperand *Ops, unsigned NumOps);
471 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
472 MVT VT2, MVT VT3, const SDOperand *Ops, unsigned NumOps);
473 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
474 MVT VT2, SDOperand Op1);
475 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
476 MVT VT2, SDOperand Op1, SDOperand Op2);
477 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
478 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
479 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
480 const SDOperand *Ops, unsigned NumOps);
483 /// getTargetNode - These are used for target selectors to create a new node
484 /// with specified return type(s), target opcode, and operands.
486 /// Note that getTargetNode returns the resultant node. If there is already a
487 /// node of the specified opcode and operands, it returns that node instead of
489 SDNode *getTargetNode(unsigned Opcode, MVT VT);
490 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1);
491 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1, SDOperand Op2);
492 SDNode *getTargetNode(unsigned Opcode, MVT VT,
493 SDOperand Op1, SDOperand Op2, SDOperand Op3);
494 SDNode *getTargetNode(unsigned Opcode, MVT VT,
495 const SDOperand *Ops, unsigned NumOps);
496 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
497 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDOperand Op1);
498 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
499 MVT VT2, SDOperand Op1, SDOperand Op2);
500 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
501 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
502 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
503 const SDOperand *Ops, unsigned NumOps);
504 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
505 SDOperand Op1, SDOperand Op2);
506 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
507 SDOperand Op1, SDOperand Op2, SDOperand Op3);
508 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
509 const SDOperand *Ops, unsigned NumOps);
510 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
511 const SDOperand *Ops, unsigned NumOps);
512 SDNode *getTargetNode(unsigned Opcode, std::vector<MVT> &ResultTys,
513 const SDOperand *Ops, unsigned NumOps);
515 /// getNodeIfExists - Get the specified node if it's already available, or
516 /// else return NULL.
517 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
518 const SDOperand *Ops, unsigned NumOps);
520 /// DAGUpdateListener - Clients of various APIs that cause global effects on
521 /// the DAG can optionally implement this interface. This allows the clients
522 /// to handle the various sorts of updates that happen.
523 class DAGUpdateListener {
525 virtual ~DAGUpdateListener();
527 /// NodeDeleted - The node N that was deleted and, if E is not null, an
528 /// equivalent node E that replaced it.
529 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
531 /// NodeUpdated - The node N that was updated.
532 virtual void NodeUpdated(SDNode *N) = 0;
535 /// RemoveDeadNode - Remove the specified node from the system. If any of its
536 /// operands then becomes dead, remove them as well. Inform UpdateListener
537 /// for each node deleted.
538 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
540 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
541 /// This can cause recursive merging of nodes in the DAG. Use the first
542 /// version if 'From' is known to have a single result, use the second
543 /// if you have two nodes with identical results, use the third otherwise.
545 /// These methods all take an optional UpdateListener, which (if not null) is
546 /// informed about nodes that are deleted and modified due to recursive
547 /// changes in the dag.
549 void ReplaceAllUsesWith(SDOperand From, SDOperand Op,
550 DAGUpdateListener *UpdateListener = 0);
551 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
552 DAGUpdateListener *UpdateListener = 0);
553 void ReplaceAllUsesWith(SDNode *From, const SDOperand *To,
554 DAGUpdateListener *UpdateListener = 0);
556 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
557 /// uses of other values produced by From.Val alone.
558 void ReplaceAllUsesOfValueWith(SDOperand From, SDOperand To,
559 DAGUpdateListener *UpdateListener = 0);
561 /// AssignNodeIds - Assign a unique node id for each node in the DAG based on
562 /// their allnodes order. It returns the maximum id.
563 unsigned AssignNodeIds();
565 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
566 /// based on their topological order. It returns the maximum id and a vector
567 /// of the SDNodes* in assigned order by reference.
568 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
570 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
572 static bool isCommutativeBinOp(unsigned Opcode) {
573 // FIXME: This should get its info from the td file, so that we can include
588 case ISD::ADDE: return true;
589 default: return false;
595 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
596 /// specified value type. If minAlign is specified, the slot size will have
597 /// at least that alignment.
598 SDOperand CreateStackTemporary(MVT VT, unsigned minAlign = 1);
600 /// FoldSetCC - Constant fold a setcc to true or false.
601 SDOperand FoldSetCC(MVT VT, SDOperand N1,
602 SDOperand N2, ISD::CondCode Cond);
604 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
605 /// use this predicate to simplify operations downstream.
606 bool SignBitIsZero(SDOperand Op, unsigned Depth = 0) const;
608 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
609 /// use this predicate to simplify operations downstream. Op and Mask are
610 /// known to be the same type.
611 bool MaskedValueIsZero(SDOperand Op, const APInt &Mask, unsigned Depth = 0)
614 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
615 /// known to be either zero or one and return them in the KnownZero/KnownOne
616 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
617 /// processing. Targets can implement the computeMaskedBitsForTargetNode
618 /// method in the TargetLowering class to allow target nodes to be understood.
619 void ComputeMaskedBits(SDOperand Op, const APInt &Mask, APInt &KnownZero,
620 APInt &KnownOne, unsigned Depth = 0) const;
622 /// ComputeNumSignBits - Return the number of times the sign bit of the
623 /// register is replicated into the other bits. We know that at least 1 bit
624 /// is always equal to the sign bit (itself), but other cases can give us
625 /// information. For example, immediately after an "SRA X, 2", we know that
626 /// the top 3 bits are all equal to each other, so we return 3. Targets can
627 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
628 /// class to allow target nodes to be understood.
629 unsigned ComputeNumSignBits(SDOperand Op, unsigned Depth = 0) const;
631 /// isVerifiedDebugInfoDesc - Returns true if the specified SDOperand has
632 /// been verified as a debug information descriptor.
633 bool isVerifiedDebugInfoDesc(SDOperand Op) const;
635 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
636 /// element of the result of the vector shuffle.
637 SDOperand getShuffleScalarElt(const SDNode *N, unsigned Idx);
640 void RemoveNodeFromCSEMaps(SDNode *N);
641 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
642 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op, void *&InsertPos);
643 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op1, SDOperand Op2,
645 SDNode *FindModifiedNodeSlot(SDNode *N, const SDOperand *Ops, unsigned NumOps,
648 void DeleteNodeNotInCSEMaps(SDNode *N);
650 // List of non-single value types.
651 std::list<std::vector<MVT> > VTList;
653 // Maps to auto-CSE operations.
654 std::vector<CondCodeSDNode*> CondCodeNodes;
656 std::vector<SDNode*> ValueTypeNodes;
657 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
658 StringMap<SDNode*> ExternalSymbols;
659 StringMap<SDNode*> TargetExternalSymbols;
662 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
663 typedef SelectionDAG::allnodes_iterator nodes_iterator;
664 static nodes_iterator nodes_begin(SelectionDAG *G) {
665 return G->allnodes_begin();
667 static nodes_iterator nodes_end(SelectionDAG *G) {
668 return G->allnodes_end();
672 } // end namespace llvm