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"
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 alist<SDNode, LargestSDNode> &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;
64 /// Allocator - Pool allocation for misc. objects that are created once per
66 BumpPtrAllocator Allocator;
68 /// VerifyNode - Sanity check the given node. Aborts if it is invalid.
69 void VerifyNode(SDNode *N);
72 SelectionDAG(TargetLowering &tli, MachineFunction &mf,
73 FunctionLoweringInfo &fli, MachineModuleInfo *mmi,
74 alist<SDNode, LargestSDNode> &NodePool)
75 : TLI(tli), MF(mf), FLI(fli), MMI(mmi), AllNodes(NodePool) {
76 EntryNode = Root = getNode(ISD::EntryToken, MVT::Other);
80 MachineFunction &getMachineFunction() const { return MF; }
81 const TargetMachine &getTarget() const;
82 TargetLowering &getTargetLoweringInfo() const { return TLI; }
83 FunctionLoweringInfo &getFunctionLoweringInfo() const { return FLI; }
84 MachineModuleInfo *getMachineModuleInfo() const { return MMI; }
86 /// viewGraph - Pop up a GraphViz/gv window with the DAG rendered using 'dot'.
88 void viewGraph(const std::string &Title);
89 void viewGraph() { return viewGraph(""); }
92 std::map<const SDNode *, std::string> NodeGraphAttrs;
95 /// clearGraphAttrs - Clear all previously defined node graph attributes.
96 /// Intended to be used from a debugging tool (eg. gdb).
97 void clearGraphAttrs();
99 /// setGraphAttrs - Set graph attributes for a node. (eg. "color=red".)
101 void setGraphAttrs(const SDNode *N, const char *Attrs);
103 /// getGraphAttrs - Get graph attributes for a node. (eg. "color=red".)
104 /// Used from getNodeAttributes.
105 const std::string getGraphAttrs(const SDNode *N) const;
107 /// setGraphColor - Convenience for setting node color attribute.
109 void setGraphColor(const SDNode *N, const char *Color);
111 typedef alist<SDNode, LargestSDNode>::const_iterator allnodes_const_iterator;
112 allnodes_const_iterator allnodes_begin() const { return AllNodes.begin(); }
113 allnodes_const_iterator allnodes_end() const { return AllNodes.end(); }
114 typedef alist<SDNode, LargestSDNode>::iterator allnodes_iterator;
115 allnodes_iterator allnodes_begin() { return AllNodes.begin(); }
116 allnodes_iterator allnodes_end() { return AllNodes.end(); }
117 alist<SDNode, LargestSDNode>::size_type allnodes_size() const {
118 return AllNodes.size();
121 /// getRoot - Return the root tag of the SelectionDAG.
123 const SDOperand &getRoot() const { return Root; }
125 /// getEntryNode - Return the token chain corresponding to the entry of the
127 const SDOperand &getEntryNode() const { return EntryNode; }
129 /// setRoot - Set the current root tag of the SelectionDAG.
131 const SDOperand &setRoot(SDOperand N) {
132 assert((!N.Val || N.getValueType() == MVT::Other) &&
133 "DAG root value is not a chain!");
137 /// Combine - This iterates over the nodes in the SelectionDAG, folding
138 /// certain types of nodes together, or eliminating superfluous nodes. When
139 /// the AfterLegalize argument is set to 'true', Combine takes care not to
140 /// generate any nodes that will be illegal on the target.
141 void Combine(bool AfterLegalize, AliasAnalysis &AA);
143 /// LegalizeTypes - This transforms the SelectionDAG into a SelectionDAG that
144 /// only uses types natively supported by the target.
146 /// Note that this is an involved process that may invalidate pointers into
148 void LegalizeTypes();
150 /// Legalize - This transforms the SelectionDAG into a SelectionDAG that is
151 /// compatible with the target instruction selector, as indicated by the
152 /// TargetLowering object.
154 /// Note that this is an involved process that may invalidate pointers into
158 /// RemoveDeadNodes - This method deletes all unreachable nodes in the
160 void RemoveDeadNodes();
162 /// DeleteNode - Remove the specified node from the system. This node must
163 /// have no referrers.
164 void DeleteNode(SDNode *N);
166 /// getVTList - Return an SDVTList that represents the list of values
168 SDVTList getVTList(MVT VT);
169 SDVTList getVTList(MVT VT1, MVT VT2);
170 SDVTList getVTList(MVT VT1, MVT VT2, MVT VT3);
171 SDVTList getVTList(const MVT *VTs, unsigned NumVTs);
173 /// getNodeValueTypes - These are obsolete, use getVTList instead.
174 const MVT *getNodeValueTypes(MVT VT) {
175 return getVTList(VT).VTs;
177 const MVT *getNodeValueTypes(MVT VT1, MVT VT2) {
178 return getVTList(VT1, VT2).VTs;
180 const MVT *getNodeValueTypes(MVT VT1, MVT VT2, MVT VT3) {
181 return getVTList(VT1, VT2, VT3).VTs;
183 const MVT *getNodeValueTypes(const std::vector<MVT> &vtList) {
184 return getVTList(&vtList[0], (unsigned)vtList.size()).VTs;
188 //===--------------------------------------------------------------------===//
189 // Node creation methods.
191 SDOperand getConstant(uint64_t Val, MVT VT, bool isTarget = false);
192 SDOperand getConstant(const APInt &Val, MVT VT, bool isTarget = false);
193 SDOperand getIntPtrConstant(uint64_t Val, bool isTarget = false);
194 SDOperand getTargetConstant(uint64_t Val, MVT VT) {
195 return getConstant(Val, VT, true);
197 SDOperand getTargetConstant(const APInt &Val, MVT VT) {
198 return getConstant(Val, VT, true);
200 SDOperand getConstantFP(double Val, MVT VT, bool isTarget = false);
201 SDOperand getConstantFP(const APFloat& Val, MVT VT, bool isTarget = false);
202 SDOperand getTargetConstantFP(double Val, MVT VT) {
203 return getConstantFP(Val, VT, true);
205 SDOperand getTargetConstantFP(const APFloat& Val, MVT VT) {
206 return getConstantFP(Val, VT, true);
208 SDOperand getGlobalAddress(const GlobalValue *GV, MVT VT,
209 int offset = 0, bool isTargetGA = false);
210 SDOperand getTargetGlobalAddress(const GlobalValue *GV, MVT VT,
212 return getGlobalAddress(GV, VT, offset, true);
214 SDOperand getFrameIndex(int FI, MVT VT, bool isTarget = false);
215 SDOperand getTargetFrameIndex(int FI, MVT VT) {
216 return getFrameIndex(FI, VT, true);
218 SDOperand getJumpTable(int JTI, MVT VT, bool isTarget = false);
219 SDOperand getTargetJumpTable(int JTI, MVT VT) {
220 return getJumpTable(JTI, VT, true);
222 SDOperand getConstantPool(Constant *C, MVT VT,
223 unsigned Align = 0, int Offs = 0, bool isT=false);
224 SDOperand getTargetConstantPool(Constant *C, MVT VT,
225 unsigned Align = 0, int Offset = 0) {
226 return getConstantPool(C, VT, Align, Offset, true);
228 SDOperand getConstantPool(MachineConstantPoolValue *C, MVT VT,
229 unsigned Align = 0, int Offs = 0, bool isT=false);
230 SDOperand getTargetConstantPool(MachineConstantPoolValue *C,
231 MVT VT, unsigned Align = 0,
233 return getConstantPool(C, VT, Align, Offset, true);
235 SDOperand getBasicBlock(MachineBasicBlock *MBB);
236 SDOperand getExternalSymbol(const char *Sym, MVT VT);
237 SDOperand getTargetExternalSymbol(const char *Sym, MVT VT);
238 SDOperand getArgFlags(ISD::ArgFlagsTy Flags);
239 SDOperand getValueType(MVT);
240 SDOperand getRegister(unsigned Reg, MVT VT);
241 SDOperand getDbgStopPoint(SDOperand Root, unsigned Line, unsigned Col,
242 const CompileUnitDesc *CU);
243 SDOperand getLabel(unsigned Opcode, SDOperand Root, unsigned LabelID);
245 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N) {
246 return getNode(ISD::CopyToReg, MVT::Other, Chain,
247 getRegister(Reg, N.getValueType()), N);
250 // This version of the getCopyToReg method takes an extra operand, which
251 // indicates that there is potentially an incoming flag value (if Flag is not
252 // null) and that there should be a flag result.
253 SDOperand getCopyToReg(SDOperand Chain, unsigned Reg, SDOperand N,
255 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
256 SDOperand Ops[] = { Chain, getRegister(Reg, N.getValueType()), N, Flag };
257 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
260 // Similar to last getCopyToReg() except parameter Reg is a SDOperand
261 SDOperand getCopyToReg(SDOperand Chain, SDOperand Reg, SDOperand N,
263 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
264 SDOperand Ops[] = { Chain, Reg, N, Flag };
265 return getNode(ISD::CopyToReg, VTs, 2, Ops, Flag.Val ? 4 : 3);
268 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT) {
269 const MVT *VTs = getNodeValueTypes(VT, MVT::Other);
270 SDOperand Ops[] = { Chain, getRegister(Reg, VT) };
271 return getNode(ISD::CopyFromReg, VTs, 2, Ops, 2);
274 // This version of the getCopyFromReg method takes an extra operand, which
275 // indicates that there is potentially an incoming flag value (if Flag is not
276 // null) and that there should be a flag result.
277 SDOperand getCopyFromReg(SDOperand Chain, unsigned Reg, MVT VT,
279 const MVT *VTs = getNodeValueTypes(VT, MVT::Other, MVT::Flag);
280 SDOperand Ops[] = { Chain, getRegister(Reg, VT), Flag };
281 return getNode(ISD::CopyFromReg, VTs, 3, Ops, Flag.Val ? 3 : 2);
284 SDOperand getCondCode(ISD::CondCode Cond);
286 /// getZeroExtendInReg - Return the expression required to zero extend the Op
287 /// value assuming it was the smaller SrcTy value.
288 SDOperand getZeroExtendInReg(SDOperand Op, MVT SrcTy);
290 /// getCALLSEQ_START - Return a new CALLSEQ_START node, which always must have
291 /// a flag result (to ensure it's not CSE'd).
292 SDOperand getCALLSEQ_START(SDOperand Chain, SDOperand Op) {
293 const MVT *VTs = getNodeValueTypes(MVT::Other, MVT::Flag);
294 SDOperand Ops[] = { Chain, Op };
295 return getNode(ISD::CALLSEQ_START, VTs, 2, Ops, 2);
298 /// getCALLSEQ_END - Return a new CALLSEQ_END node, which always must have a
299 /// flag result (to ensure it's not CSE'd).
300 SDOperand getCALLSEQ_END(SDOperand Chain, SDOperand Op1, SDOperand Op2,
302 SDVTList NodeTys = getVTList(MVT::Other, MVT::Flag);
303 SmallVector<SDOperand, 4> Ops;
304 Ops.push_back(Chain);
307 Ops.push_back(InFlag);
308 return getNode(ISD::CALLSEQ_END, NodeTys, &Ops[0],
309 (unsigned)Ops.size() - (InFlag.Val == 0 ? 1 : 0));
312 /// getNode - Gets or creates the specified node.
314 SDOperand getNode(unsigned Opcode, MVT VT);
315 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N);
316 SDOperand getNode(unsigned Opcode, MVT VT, SDOperand N1, SDOperand N2);
317 SDOperand getNode(unsigned Opcode, MVT VT,
318 SDOperand N1, SDOperand N2, SDOperand N3);
319 SDOperand getNode(unsigned Opcode, MVT VT,
320 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
321 SDOperand getNode(unsigned Opcode, MVT VT,
322 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
324 SDOperand getNode(unsigned Opcode, MVT VT,
325 const SDOperand *Ops, unsigned NumOps);
326 SDOperand getNode(unsigned Opcode, MVT VT,
327 const SDUse *Ops, unsigned NumOps);
328 SDOperand getNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
329 const SDOperand *Ops, unsigned NumOps);
330 SDOperand getNode(unsigned Opcode, const MVT *VTs, unsigned NumVTs,
331 const SDOperand *Ops, unsigned NumOps);
332 SDOperand getNode(unsigned Opcode, SDVTList VTs);
333 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N);
334 SDOperand getNode(unsigned Opcode, SDVTList VTs, SDOperand N1, SDOperand N2);
335 SDOperand getNode(unsigned Opcode, SDVTList VTs,
336 SDOperand N1, SDOperand N2, SDOperand N3);
337 SDOperand getNode(unsigned Opcode, SDVTList VTs,
338 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4);
339 SDOperand getNode(unsigned Opcode, SDVTList VTs,
340 SDOperand N1, SDOperand N2, SDOperand N3, SDOperand N4,
342 SDOperand getNode(unsigned Opcode, SDVTList VTs,
343 const SDOperand *Ops, unsigned NumOps);
345 SDOperand getMemcpy(SDOperand Chain, SDOperand Dst, SDOperand Src,
346 SDOperand Size, unsigned Align,
348 const Value *DstSV, uint64_t DstSVOff,
349 const Value *SrcSV, uint64_t SrcSVOff);
351 SDOperand getMemmove(SDOperand Chain, SDOperand Dst, SDOperand Src,
352 SDOperand Size, unsigned Align,
353 const Value *DstSV, uint64_t DstOSVff,
354 const Value *SrcSV, uint64_t SrcSVOff);
356 SDOperand getMemset(SDOperand Chain, SDOperand Dst, SDOperand Src,
357 SDOperand Size, unsigned Align,
358 const Value *DstSV, uint64_t DstSVOff);
360 /// getSetCC - Helper function to make it easier to build SetCC's if you just
361 /// have an ISD::CondCode instead of an SDOperand.
363 SDOperand getSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
364 ISD::CondCode Cond) {
365 return getNode(ISD::SETCC, VT, LHS, RHS, getCondCode(Cond));
368 /// getVSetCC - Helper function to make it easier to build VSetCC's nodes
369 /// if you just have an ISD::CondCode instead of an SDOperand.
371 SDOperand getVSetCC(MVT VT, SDOperand LHS, SDOperand RHS,
372 ISD::CondCode Cond) {
373 return getNode(ISD::VSETCC, VT, LHS, RHS, getCondCode(Cond));
376 /// getSelectCC - Helper function to make it easier to build SelectCC's if you
377 /// just have an ISD::CondCode instead of an SDOperand.
379 SDOperand getSelectCC(SDOperand LHS, SDOperand RHS,
380 SDOperand True, SDOperand False, ISD::CondCode Cond) {
381 return getNode(ISD::SELECT_CC, True.getValueType(), LHS, RHS, True, False,
385 /// getVAArg - VAArg produces a result and token chain, and takes a pointer
386 /// and a source value as input.
387 SDOperand getVAArg(MVT VT, SDOperand Chain, SDOperand Ptr,
390 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
392 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
393 SDOperand Cmp, SDOperand Swp, const Value* PtrVal,
394 unsigned Alignment=0);
396 /// getAtomic - Gets a node for an atomic op, produces result and chain, takes
398 SDOperand getAtomic(unsigned Opcode, SDOperand Chain, SDOperand Ptr,
399 SDOperand Val, const Value* PtrVal,
400 unsigned Alignment = 0);
402 /// getMergeValues - Create a MERGE_VALUES node from the given operands.
403 /// Allowed to return something different (and simpler) if Simplify is true.
404 SDOperand getMergeValues(const SDOperand *Ops, unsigned NumOps,
405 bool Simplify = true);
407 /// getMergeValues - Create a MERGE_VALUES node from the given types and ops.
408 /// Allowed to return something different (and simpler) if Simplify is true.
409 /// May be faster than the above version if VTs is known and NumOps is large.
410 SDOperand getMergeValues(SDVTList VTs, const SDOperand *Ops, unsigned NumOps,
411 bool Simplify = true) {
412 if (Simplify && NumOps == 1)
414 return getNode(ISD::MERGE_VALUES, VTs, Ops, NumOps);
417 /// getLoad - Loads are not normal binary operators: their result type is not
418 /// determined by their operands, and they produce a value AND a token chain.
420 SDOperand getLoad(MVT VT, SDOperand Chain, SDOperand Ptr,
421 const Value *SV, int SVOffset, bool isVolatile=false,
422 unsigned Alignment=0);
423 SDOperand getExtLoad(ISD::LoadExtType ExtType, MVT VT,
424 SDOperand Chain, SDOperand Ptr, const Value *SV,
425 int SVOffset, MVT EVT, bool isVolatile=false,
426 unsigned Alignment=0);
427 SDOperand getIndexedLoad(SDOperand OrigLoad, SDOperand Base,
428 SDOperand Offset, ISD::MemIndexedMode AM);
429 SDOperand getLoad(ISD::MemIndexedMode AM, ISD::LoadExtType ExtType,
430 MVT VT, SDOperand Chain,
431 SDOperand Ptr, SDOperand Offset,
432 const Value *SV, int SVOffset, MVT EVT,
433 bool isVolatile=false, unsigned Alignment=0);
435 /// getStore - Helper function to build ISD::STORE nodes.
437 SDOperand getStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
438 const Value *SV, int SVOffset, bool isVolatile=false,
439 unsigned Alignment=0);
440 SDOperand getTruncStore(SDOperand Chain, SDOperand Val, SDOperand Ptr,
441 const Value *SV, int SVOffset, MVT TVT,
442 bool isVolatile=false, unsigned Alignment=0);
443 SDOperand getIndexedStore(SDOperand OrigStoe, SDOperand Base,
444 SDOperand Offset, ISD::MemIndexedMode AM);
446 // getSrcValue - Construct a node to track a Value* through the backend.
447 SDOperand getSrcValue(const Value *v);
449 // getMemOperand - Construct a node to track a memory reference
450 // through the backend.
451 SDOperand getMemOperand(const MachineMemOperand &MO);
453 /// UpdateNodeOperands - *Mutate* the specified node in-place to have the
454 /// specified operands. If the resultant node already exists in the DAG,
455 /// this does not modify the specified node, instead it returns the node that
456 /// already exists. If the resultant node does not exist in the DAG, the
457 /// input node is returned. As a degenerate case, if you specify the same
458 /// input operands as the node already has, the input node is returned.
459 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op);
460 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2);
461 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
463 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
464 SDOperand Op3, SDOperand Op4);
465 SDOperand UpdateNodeOperands(SDOperand N, SDOperand Op1, SDOperand Op2,
466 SDOperand Op3, SDOperand Op4, SDOperand Op5);
467 SDOperand UpdateNodeOperands(SDOperand N,
468 const SDOperand *Ops, unsigned NumOps);
470 /// SelectNodeTo - These are used for target selectors to *mutate* the
471 /// specified node to have the specified return type, Target opcode, and
472 /// operands. Note that target opcodes are stored as
473 /// ~TargetOpcode in the node opcode field. The resultant node is returned.
474 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT);
475 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT, SDOperand Op1);
476 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
477 SDOperand Op1, SDOperand Op2);
478 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
479 SDOperand Op1, SDOperand Op2, SDOperand Op3);
480 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT,
481 const SDOperand *Ops, unsigned NumOps);
482 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1, MVT VT2);
483 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
484 MVT VT2, const SDOperand *Ops, unsigned NumOps);
485 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
486 MVT VT2, MVT VT3, const SDOperand *Ops, unsigned NumOps);
487 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
488 MVT VT2, SDOperand Op1);
489 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
490 MVT VT2, SDOperand Op1, SDOperand Op2);
491 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, MVT VT1,
492 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
493 SDNode *SelectNodeTo(SDNode *N, unsigned TargetOpc, SDVTList VTs,
494 const SDOperand *Ops, unsigned NumOps);
496 /// MorphNodeTo - These *mutate* the specified node to have the specified
497 /// return type, opcode, and operands.
498 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT);
499 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT, SDOperand Op1);
500 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
501 SDOperand Op1, SDOperand Op2);
502 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
503 SDOperand Op1, SDOperand Op2, SDOperand Op3);
504 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT,
505 const SDOperand *Ops, unsigned NumOps);
506 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1, MVT VT2);
507 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
508 MVT VT2, const SDOperand *Ops, unsigned NumOps);
509 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
510 MVT VT2, MVT VT3, const SDOperand *Ops, unsigned NumOps);
511 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
512 MVT VT2, SDOperand Op1);
513 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
514 MVT VT2, SDOperand Op1, SDOperand Op2);
515 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, MVT VT1,
516 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
517 SDNode *MorphNodeTo(SDNode *N, unsigned Opc, SDVTList VTs,
518 const SDOperand *Ops, unsigned NumOps);
520 /// getTargetNode - These are used for target selectors to create a new node
521 /// with specified return type(s), target opcode, and operands.
523 /// Note that getTargetNode returns the resultant node. If there is already a
524 /// node of the specified opcode and operands, it returns that node instead of
526 SDNode *getTargetNode(unsigned Opcode, MVT VT);
527 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1);
528 SDNode *getTargetNode(unsigned Opcode, MVT VT, SDOperand Op1, SDOperand Op2);
529 SDNode *getTargetNode(unsigned Opcode, MVT VT,
530 SDOperand Op1, SDOperand Op2, SDOperand Op3);
531 SDNode *getTargetNode(unsigned Opcode, MVT VT,
532 const SDOperand *Ops, unsigned NumOps);
533 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2);
534 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, SDOperand Op1);
535 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
536 MVT VT2, SDOperand Op1, SDOperand Op2);
537 SDNode *getTargetNode(unsigned Opcode, MVT VT1,
538 MVT VT2, SDOperand Op1, SDOperand Op2, SDOperand Op3);
539 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2,
540 const SDOperand *Ops, unsigned NumOps);
541 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
542 SDOperand Op1, SDOperand Op2);
543 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
544 SDOperand Op1, SDOperand Op2, SDOperand Op3);
545 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3,
546 const SDOperand *Ops, unsigned NumOps);
547 SDNode *getTargetNode(unsigned Opcode, MVT VT1, MVT VT2, MVT VT3, MVT VT4,
548 const SDOperand *Ops, unsigned NumOps);
549 SDNode *getTargetNode(unsigned Opcode, const std::vector<MVT> &ResultTys,
550 const SDOperand *Ops, unsigned NumOps);
552 /// getNodeIfExists - Get the specified node if it's already available, or
553 /// else return NULL.
554 SDNode *getNodeIfExists(unsigned Opcode, SDVTList VTs,
555 const SDOperand *Ops, unsigned NumOps);
557 /// DAGUpdateListener - Clients of various APIs that cause global effects on
558 /// the DAG can optionally implement this interface. This allows the clients
559 /// to handle the various sorts of updates that happen.
560 class DAGUpdateListener {
562 virtual ~DAGUpdateListener();
564 /// NodeDeleted - The node N that was deleted and, if E is not null, an
565 /// equivalent node E that replaced it.
566 virtual void NodeDeleted(SDNode *N, SDNode *E) = 0;
568 /// NodeUpdated - The node N that was updated.
569 virtual void NodeUpdated(SDNode *N) = 0;
572 /// RemoveDeadNode - Remove the specified node from the system. If any of its
573 /// operands then becomes dead, remove them as well. Inform UpdateListener
574 /// for each node deleted.
575 void RemoveDeadNode(SDNode *N, DAGUpdateListener *UpdateListener = 0);
577 /// RemoveDeadNodes - This method deletes the unreachable nodes in the
578 /// given list, and any nodes that become unreachable as a result.
579 void RemoveDeadNodes(SmallVectorImpl<SDNode *> &DeadNodes,
580 DAGUpdateListener *UpdateListener = 0);
582 /// ReplaceAllUsesWith - Modify anything using 'From' to use 'To' instead.
583 /// This can cause recursive merging of nodes in the DAG. Use the first
584 /// version if 'From' is known to have a single result, use the second
585 /// if you have two nodes with identical results, use the third otherwise.
587 /// These methods all take an optional UpdateListener, which (if not null) is
588 /// informed about nodes that are deleted and modified due to recursive
589 /// changes in the dag.
591 void ReplaceAllUsesWith(SDOperand From, SDOperand Op,
592 DAGUpdateListener *UpdateListener = 0);
593 void ReplaceAllUsesWith(SDNode *From, SDNode *To,
594 DAGUpdateListener *UpdateListener = 0);
595 void ReplaceAllUsesWith(SDNode *From, const SDOperand *To,
596 DAGUpdateListener *UpdateListener = 0);
598 /// ReplaceAllUsesOfValueWith - Replace any uses of From with To, leaving
599 /// uses of other values produced by From.Val alone.
600 void ReplaceAllUsesOfValueWith(SDOperand From, SDOperand To,
601 DAGUpdateListener *UpdateListener = 0);
603 /// ReplaceAllUsesOfValuesWith - Like ReplaceAllUsesOfValueWith, but
604 /// for multiple values at once. This correctly handles the case where
605 /// there is an overlap between the From values and the To values.
606 void ReplaceAllUsesOfValuesWith(const SDOperand *From, const SDOperand *To,
608 DAGUpdateListener *UpdateListener = 0);
610 /// AssignTopologicalOrder - Assign a unique node id for each node in the DAG
611 /// based on their topological order. It returns the maximum id and a vector
612 /// of the SDNodes* in assigned order by reference.
613 unsigned AssignTopologicalOrder(std::vector<SDNode*> &TopOrder);
615 /// isCommutativeBinOp - Returns true if the opcode is a commutative binary
617 static bool isCommutativeBinOp(unsigned Opcode) {
618 // FIXME: This should get its info from the td file, so that we can include
633 case ISD::ADDE: return true;
634 default: return false;
640 /// CreateStackTemporary - Create a stack temporary, suitable for holding the
641 /// specified value type. If minAlign is specified, the slot size will have
642 /// at least that alignment.
643 SDOperand CreateStackTemporary(MVT VT, unsigned minAlign = 1);
645 /// FoldSetCC - Constant fold a setcc to true or false.
646 SDOperand FoldSetCC(MVT VT, SDOperand N1,
647 SDOperand N2, ISD::CondCode Cond);
649 /// SignBitIsZero - Return true if the sign bit of Op is known to be zero. We
650 /// use this predicate to simplify operations downstream.
651 bool SignBitIsZero(SDOperand Op, unsigned Depth = 0) const;
653 /// MaskedValueIsZero - Return true if 'Op & Mask' is known to be zero. We
654 /// use this predicate to simplify operations downstream. Op and Mask are
655 /// known to be the same type.
656 bool MaskedValueIsZero(SDOperand Op, const APInt &Mask, unsigned Depth = 0)
659 /// ComputeMaskedBits - Determine which of the bits specified in Mask are
660 /// known to be either zero or one and return them in the KnownZero/KnownOne
661 /// bitsets. This code only analyzes bits in Mask, in order to short-circuit
662 /// processing. Targets can implement the computeMaskedBitsForTargetNode
663 /// method in the TargetLowering class to allow target nodes to be understood.
664 void ComputeMaskedBits(SDOperand Op, const APInt &Mask, APInt &KnownZero,
665 APInt &KnownOne, unsigned Depth = 0) const;
667 /// ComputeNumSignBits - Return the number of times the sign bit of the
668 /// register is replicated into the other bits. We know that at least 1 bit
669 /// is always equal to the sign bit (itself), but other cases can give us
670 /// information. For example, immediately after an "SRA X, 2", we know that
671 /// the top 3 bits are all equal to each other, so we return 3. Targets can
672 /// implement the ComputeNumSignBitsForTarget method in the TargetLowering
673 /// class to allow target nodes to be understood.
674 unsigned ComputeNumSignBits(SDOperand Op, unsigned Depth = 0) const;
676 /// isVerifiedDebugInfoDesc - Returns true if the specified SDOperand has
677 /// been verified as a debug information descriptor.
678 bool isVerifiedDebugInfoDesc(SDOperand Op) const;
680 /// getShuffleScalarElt - Returns the scalar element that will make up the ith
681 /// element of the result of the vector shuffle.
682 SDOperand getShuffleScalarElt(const SDNode *N, unsigned Idx);
685 inline alist_traits<SDNode, LargestSDNode>::AllocatorType &getAllocator();
686 void RemoveNodeFromCSEMaps(SDNode *N);
687 SDNode *AddNonLeafNodeToCSEMaps(SDNode *N);
688 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op, void *&InsertPos);
689 SDNode *FindModifiedNodeSlot(SDNode *N, SDOperand Op1, SDOperand Op2,
691 SDNode *FindModifiedNodeSlot(SDNode *N, const SDOperand *Ops, unsigned NumOps,
694 void DeleteNodeNotInCSEMaps(SDNode *N);
696 unsigned getMVTAlignment(MVT MemoryVT) const;
698 // List of non-single value types.
699 std::vector<SDVTList> VTList;
701 // Maps to auto-CSE operations.
702 std::vector<CondCodeSDNode*> CondCodeNodes;
704 std::vector<SDNode*> ValueTypeNodes;
705 std::map<MVT, SDNode*, MVT::compareRawBits> ExtendedValueTypeNodes;
706 StringMap<SDNode*> ExternalSymbols;
707 StringMap<SDNode*> TargetExternalSymbols;
710 template <> struct GraphTraits<SelectionDAG*> : public GraphTraits<SDNode*> {
711 typedef SelectionDAG::allnodes_iterator nodes_iterator;
712 static nodes_iterator nodes_begin(SelectionDAG *G) {
713 return G->allnodes_begin();
715 static nodes_iterator nodes_end(SelectionDAG *G) {
716 return G->allnodes_end();
720 } // end namespace llvm