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, SDOperandPtr Ops, unsigned NumOps);
310 SDOperand getNode(unsigned Opcode, std::vector<MVT> &ResultTys,
311 SDOperandPtr Ops, unsigned NumOps);
312 SDOperand getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
313 SDOperandPtr Ops, unsigned NumOps);
314 SDOperand getNode(unsigned Opcode, SDVTList VTs);
315 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N);
316 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N1, SDOperand N2);
317 SDOperand getNode(unsigned Opcode, SDVTList VTs,
318 SDOperand N1, SDOperand N2, SDOperand N3);
319 SDOperand getNode(unsigned Opcode, SDVTList VTs,
320 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
321 SDOperand getNode(unsigned Opcode, SDVTList VTs,
322 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
324 SDOperand getNode(unsigned Opcode, SDVTList VTs,
325 SDOperandPtr Ops, unsigned NumOps);
327 SDOperand getMemcpy(SDOperand Chain, SDOperand Dst, SDOperand Src,
328 SDOperand Size, unsigned Align,
330 const Value *DstSV, uint64_t DstSVOff,
331 const Value *SrcSV, uint64_t SrcSVOff);
333 SDOperand getMemmove(SDOperand Chain, SDOperand Dst, SDOperand Src,
334 SDOperand Size, unsigned Align,
335 const Value *DstSV, uint64_t DstOSVff,
336 const Value *SrcSV, uint64_t SrcSVOff);
338 SDOperand getMemset(SDOperand Chain, SDOperand Dst, SDOperand Src,
339 SDOperand Size, unsigned Align,
340 const Value *DstSV, uint64_t DstSVOff);
342 /// getSetCC - Helper function to make it easier to build SetCC's if you just
343 /// have an ISD::CondCode instead of an SDOperand.
345 SDOperand getSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
346 ISD::CondCode Cond) {
347 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
350 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
351 /// if you just have an ISD::CondCode instead of an SDOperand.
353 SDOperand getVSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
354 ISD::CondCode Cond) {
355 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
358 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
359 /// just have an ISD::CondCode instead of an SDOperand.
361 SDOperand getSelectCC(SDOperand LHS, SDOperand RHS,
362 SDOperand True, SDOperand False, ISD::CondCode Cond) {
363 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
367 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
368 /// and a source value as input.
369 SDOperand getVAArg(MVT VT, SDOperand Chain, SDOperand Ptr,
372 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
374 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
375 SDOperand Cmp, SDOperand Swp, const Value* PtrVal,
376 unsigned Alignment=0);
378 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
380 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
381 SDOperand Val, const Value* PtrVal,
382 unsigned Alignment = 0);
384 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
385 /// Allowed to return something different (and simpler) if Simplify is true.
386 SDOperand getMergeValues(SDOperandPtr Ops, unsigned NumOps,
387 bool Simplify = true);
389 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
390 /// Allowed to return something different (and simpler) if Simplify is true.
391 /// May be faster than the above version if VTs is known and NumOps is large.
392 SDOperand getMergeValues(SDVTList VTs, SDOperandPtr Ops, unsigned NumOps,
393 bool Simplify = true) {
394 if (Simplify && NumOps == 1)
396 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
399 /// getLoad - Loads are not normal binary operators: their result type is not
400 /// determined by their operands, and they produce a value AND a token chain.
402 SDOperand getLoad(MVT VT, SDOperand Chain, SDOperand Ptr,
403 const Value *SV, int SVOffset, bool isVolatile=false,
404 unsigned Alignment=0);
405 SDOperand getExtLoad(ISD::LoadExtType ExtType, MVT VT,
406 SDOperand Chain, SDOperand Ptr, const Value *SV,
407 int SVOffset, MVT EVT, bool isVolatile=false,
408 unsigned Alignment=0);
409 SDOperand getIndexedLoad(SDOperand OrigLoad, SDOperand Base,
410 SDOperand Offset, ISD::MemIndexedMode AM);
411 SDOperand getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
412 MVT VT, SDOperand Chain,
413 SDOperand Ptr, SDOperand Offset,
414 const Value *SV, int SVOffset, MVT EVT,
415 bool isVolatile=false, unsigned Alignment=0);
417 /// getStore - Helper function to build ISD::STORE nodes.
419 SDOperand getStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
420 const Value *SV, int SVOffset, bool isVolatile=false,
421 unsigned Alignment=0);
422 SDOperand getTruncStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
423 const Value *SV, int SVOffset, MVT TVT,
424 bool isVolatile=false, unsigned Alignment=0);
425 SDOperand getIndexedStore(SDOperand OrigStoe, SDOperand Base,
426 SDOperand Offset, ISD::MemIndexedMode AM);
428 // getSrcValue - Construct a node to track a Value* through the backend.
429 SDOperand getSrcValue(const Value *v);
431 // getMemOperand - Construct a node to track a memory reference
432 // through the backend.
433 SDOperand getMemOperand(const MachineMemOperand &MO);
435 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
436 /// specified operands. If the resultant node already exists in the DAG,
437 /// this does not modify the specified node, instead it returns the node that
438 /// already exists. If the resultant node does not exist in the DAG, the
439 /// input node is returned. As a degenerate case, if you specify the same
440 /// input operands as the node already has, the input node is returned.
441 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op);
442 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2);
443 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
445 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
446 SDOperand Op3, SDOperand Op4);
447 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
448 SDOperand Op3, SDOperand Op4, SDOperand Op5);
449 SDOperand UpdateNodeOperands(SDOperand N, SDOperandPtr Ops, unsigned NumOps);
451 /// SelectNodeTo - These are used for target selectors to *mutate* the
452 /// specified node to have the specified return type, Target opcode, and
453 /// operands. Note that target opcodes are stored as
454 /// ISD::BUILTIN_OP_END+TargetOpcode in the node opcode field. The 0th value
455 /// of the resultant node is returned.
456 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
457 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDOperand Op1);
458 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
459 SDOperand Op1, SDOperand Op2);
460 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
461 SDOperand Op1, SDOperand Op2, SDOperand Op3);
462 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
463 SDOperandPtr Ops, unsigned NumOps);
464 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
465 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
466 MVT VT2, SDOperandPtr Ops, unsigned NumOps);
467 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
468 MVT VT2, MVT VT3, SDOperandPtr Ops, unsigned NumOps);
469 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
470 MVT VT2, SDOperand Op1);
471 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
472 MVT VT2, SDOperand Op1, SDOperand Op2);
473 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
474 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
475 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
476 SDOperandPtr Ops, unsigned NumOps);
479 /// getTargetNode - These are used for target selectors to create a new node
480 /// with specified return type(s), target opcode, and operands.
482 /// Note that getTargetNode returns the resultant node. If there is already a
483 /// node of the specified opcode and operands, it returns that node instead of
485 SDNode *getTargetNode(unsigned Opcode, MVT VT);
486 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1);
487 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1, SDOperand Op2);
488 SDNode *getTargetNode(unsigned Opcode, MVT VT,
489 SDOperand Op1, SDOperand Op2, SDOperand Op3);
490 SDNode *getTargetNode(unsigned Opcode, MVT VT,
491 SDOperandPtr Ops, unsigned NumOps);
492 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
493 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDOperand Op1);
494 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
495 MVT VT2, SDOperand Op1, SDOperand Op2);
496 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
497 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
498 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
499 SDOperandPtr Ops, unsigned NumOps);
500 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
501 SDOperand Op1, SDOperand Op2);
502 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
503 SDOperand Op1, SDOperand Op2, SDOperand Op3);
504 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
505 SDOperandPtr Ops, unsigned NumOps);
506 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
507 SDOperandPtr Ops, unsigned NumOps);
508 SDNode *getTargetNode(unsigned Opcode, std::vector<MVT> &ResultTys,
509 SDOperandPtr Ops, unsigned NumOps);
511 /// getNodeIfExists - Get the specified node if it's already available, or
512 /// else return NULL.
513 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
514 SDOperandPtr Ops, unsigned NumOps);
516 /// DAGUpdateListener - Clients of various APIs that cause global effects on
517 /// the DAG can optionally implement this interface. This allows the clients
518 /// to handle the various sorts of updates that happen.
519 class DAGUpdateListener {
521 virtual ~DAGUpdateListener();
523 /// NodeDeleted - The node N that was deleted and, if E is not null, an
524 /// equivalent node E that replaced it.
525 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
527 /// NodeUpdated - The node N that was updated.
528 virtual void NodeUpdated(SDNode *N) = 0;
531 /// RemoveDeadNode - Remove the specified node from the system. If any of its
532 /// operands then becomes dead, remove them as well. Inform UpdateListener
533 /// for each node deleted.
534 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
536 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
537 /// This can cause recursive merging of nodes in the DAG. Use the first
538 /// version if 'From' is known to have a single result, use the second
539 /// if you have two nodes with identical results, use the third otherwise.
541 /// These methods all take an optional UpdateListener, which (if not null) is
542 /// informed about nodes that are deleted and modified due to recursive
543 /// changes in the dag.
545 void ReplaceAllUsesWith(SDOperand From, SDOperand Op,
546 DAGUpdateListener *UpdateListener = 0);
547 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
548 DAGUpdateListener *UpdateListener = 0);
549 void ReplaceAllUsesWith(SDNode *From, SDOperandPtr To,
550 DAGUpdateListener *UpdateListener = 0);
552 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
553 /// uses of other values produced by From.Val alone.
554 void ReplaceAllUsesOfValueWith(SDOperand From, SDOperand To,
555 DAGUpdateListener *UpdateListener = 0);
557 /// AssignNodeIds - Assign a unique node id for each node in the DAG based on
558 /// their allnodes order. It returns the maximum id.
559 unsigned AssignNodeIds();
561 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
562 /// based on their topological order. It returns the maximum id and a vector
563 /// of the SDNodes* in assigned order by reference.
564 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
566 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
568 static bool isCommutativeBinOp(unsigned Opcode) {
569 // FIXME: This should get its info from the td file, so that we can include
584 case ISD::ADDE: return true;
585 default: return false;
591 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
592 /// specified value type. If minAlign is specified, the slot size will have
593 /// at least that alignment.
594 SDOperand CreateStackTemporary(MVT VT, unsigned minAlign = 1);
596 /// FoldSetCC - Constant fold a setcc to true or false.
597 SDOperand FoldSetCC(MVT VT, SDOperand N1,
598 SDOperand N2, ISD::CondCode Cond);
600 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
601 /// use this predicate to simplify operations downstream.
602 bool SignBitIsZero(SDOperand Op, unsigned Depth = 0) const;
604 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
605 /// use this predicate to simplify operations downstream. Op and Mask are
606 /// known to be the same type.
607 bool MaskedValueIsZero(SDOperand Op, const APInt &Mask, unsigned Depth = 0)
610 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
611 /// known to be either zero or one and return them in the KnownZero/KnownOne
612 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
613 /// processing. Targets can implement the computeMaskedBitsForTargetNode
614 /// method in the TargetLowering class to allow target nodes to be understood.
615 void ComputeMaskedBits(SDOperand Op, const APInt &Mask, APInt &KnownZero,
616 APInt &KnownOne, unsigned Depth = 0) const;
618 /// ComputeNumSignBits - Return the number of times the sign bit of the
619 /// register is replicated into the other bits. We know that at least 1 bit
620 /// is always equal to the sign bit (itself), but other cases can give us
621 /// information. For example, immediately after an "SRA X, 2", we know that
622 /// the top 3 bits are all equal to each other, so we return 3. Targets can
623 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
624 /// class to allow target nodes to be understood.
625 unsigned ComputeNumSignBits(SDOperand Op, unsigned Depth = 0) const;
627 /// isVerifiedDebugInfoDesc - Returns true if the specified SDOperand has
628 /// been verified as a debug information descriptor.
629 bool isVerifiedDebugInfoDesc(SDOperand Op) const;
631 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
632 /// element of the result of the vector shuffle.
633 SDOperand getShuffleScalarElt(const SDNode *N, unsigned Idx);
636 void RemoveNodeFromCSEMaps(SDNode *N);
637 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
638 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op, void *&InsertPos);
639 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op1, SDOperand Op2,
641 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperandPtr Ops, unsigned NumOps,
644 void DeleteNodeNotInCSEMaps(SDNode *N);
646 // List of non-single value types.
647 std::list<std::vector<MVT> > VTList;
649 // Maps to auto-CSE operations.
650 std::vector<CondCodeSDNode*> CondCodeNodes;
652 std::vector<SDNode*> ValueTypeNodes;
653 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
654 StringMap<SDNode*> ExternalSymbols;
655 StringMap<SDNode*> TargetExternalSymbols;
658 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
659 typedef SelectionDAG::allnodes_iterator nodes_iterator;
660 static nodes_iterator nodes_begin(SelectionDAG *G) {
661 return G->allnodes_begin();
663 static nodes_iterator nodes_end(SelectionDAG *G) {
664 return G->allnodes_end();
668 } // end namespace llvm