1 //===-- Attributes.cpp - Implement AttributesList -------------------------===//
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 implements the Attributes, AttributeImpl, AttrBuilder,
11 // AttributeListImpl, and AttrListPtr classes.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Attributes.h"
16 #include "AttributesImpl.h"
17 #include "LLVMContextImpl.h"
18 #include "llvm/Type.h"
19 #include "llvm/ADT/StringExtras.h"
20 #include "llvm/ADT/FoldingSet.h"
21 #include "llvm/Support/Atomic.h"
22 #include "llvm/Support/Mutex.h"
23 #include "llvm/Support/Debug.h"
24 #include "llvm/Support/ManagedStatic.h"
25 #include "llvm/Support/raw_ostream.h"
28 //===----------------------------------------------------------------------===//
29 // Attributes Implementation
30 //===----------------------------------------------------------------------===//
32 Attributes Attributes::get(LLVMContext &Context, ArrayRef<AttrVal> Vals) {
34 for (ArrayRef<AttrVal>::iterator I = Vals.begin(), E = Vals.end();
37 return Attributes::get(Context, B);
40 Attributes Attributes::get(LLVMContext &Context, AttrBuilder &B) {
41 // If there are no attributes, return an empty Attributes class.
42 if (!B.hasAttributes())
45 // Otherwise, build a key to look up the existing attributes.
46 LLVMContextImpl *pImpl = Context.pImpl;
48 ID.AddInteger(B.Raw());
51 AttributesImpl *PA = pImpl->AttrsSet.FindNodeOrInsertPos(ID, InsertPoint);
54 // If we didn't find any existing attributes of the same shape then create a
55 // new one and insert it.
56 PA = new AttributesImpl(B.Raw());
57 pImpl->AttrsSet.InsertNode(PA, InsertPoint);
60 // Return the AttributesList that we found or created.
61 return Attributes(PA);
64 bool Attributes::hasAttribute(AttrVal Val) const {
65 return Attrs && Attrs->hasAttribute(Val);
68 bool Attributes::hasAttributes() const {
69 return Attrs && Attrs->hasAttributes();
72 bool Attributes::hasAttributes(const Attributes &A) const {
73 return Attrs && Attrs->hasAttributes(A);
76 /// This returns the alignment field of an attribute as a byte alignment value.
77 unsigned Attributes::getAlignment() const {
78 if (!hasAttribute(Attributes::Alignment))
80 return 1U << ((Attrs->getAlignment() >> 16) - 1);
83 /// This returns the stack alignment field of an attribute as a byte alignment
85 unsigned Attributes::getStackAlignment() const {
86 if (!hasAttribute(Attributes::StackAlignment))
88 return 1U << ((Attrs->getStackAlignment() >> 26) - 1);
91 uint64_t Attributes::Raw() const {
92 return Attrs ? Attrs->Raw() : 0;
95 Attributes Attributes::typeIncompatible(Type *Ty) {
96 AttrBuilder Incompatible;
98 if (!Ty->isIntegerTy())
99 // Attributes that only apply to integers.
100 Incompatible.addAttribute(Attributes::SExt)
101 .addAttribute(Attributes::ZExt);
103 if (!Ty->isPointerTy())
104 // Attributes that only apply to pointers.
105 Incompatible.addAttribute(Attributes::ByVal)
106 .addAttribute(Attributes::Nest)
107 .addAttribute(Attributes::NoAlias)
108 .addAttribute(Attributes::NoCapture)
109 .addAttribute(Attributes::StructRet);
111 return Attributes::get(Ty->getContext(), Incompatible);
114 /// encodeLLVMAttributesForBitcode - This returns an integer containing an
115 /// encoding of all the LLVM attributes found in the given attribute bitset.
116 /// Any change to this encoding is a breaking change to bitcode compatibility.
117 uint64_t Attributes::encodeLLVMAttributesForBitcode(Attributes Attrs) {
118 // FIXME: It doesn't make sense to store the alignment information as an
119 // expanded out value, we should store it as a log2 value. However, we can't
120 // just change that here without breaking bitcode compatibility. If this ever
121 // becomes a problem in practice, we should introduce new tag numbers in the
122 // bitcode file and have those tags use a more efficiently encoded alignment
125 // Store the alignment in the bitcode as a 16-bit raw value instead of a 5-bit
126 // log2 encoded value. Shift the bits above the alignment up by 11 bits.
127 uint64_t EncodedAttrs = Attrs.Raw() & 0xffff;
128 if (Attrs.hasAttribute(Attributes::Alignment))
129 EncodedAttrs |= Attrs.getAlignment() << 16;
130 EncodedAttrs |= (Attrs.Raw() & (0xffffULL << 21)) << 11;
134 /// decodeLLVMAttributesForBitcode - This returns an attribute bitset containing
135 /// the LLVM attributes that have been decoded from the given integer. This
136 /// function must stay in sync with 'encodeLLVMAttributesForBitcode'.
137 Attributes Attributes::decodeLLVMAttributesForBitcode(LLVMContext &C,
138 uint64_t EncodedAttrs) {
139 // The alignment is stored as a 16-bit raw value from bits 31--16. We shift
140 // the bits above 31 down by 11 bits.
141 unsigned Alignment = (EncodedAttrs & (0xffffULL << 16)) >> 16;
142 assert((!Alignment || isPowerOf2_32(Alignment)) &&
143 "Alignment must be a power of two.");
145 AttrBuilder B(EncodedAttrs & 0xffff);
147 B.addAlignmentAttr(Alignment);
148 B.addRawValue((EncodedAttrs & (0xffffULL << 32)) >> 11);
149 return Attributes::get(C, B);
152 std::string Attributes::getAsString() const {
154 if (hasAttribute(Attributes::ZExt))
155 Result += "zeroext ";
156 if (hasAttribute(Attributes::SExt))
157 Result += "signext ";
158 if (hasAttribute(Attributes::NoReturn))
159 Result += "noreturn ";
160 if (hasAttribute(Attributes::NoUnwind))
161 Result += "nounwind ";
162 if (hasAttribute(Attributes::UWTable))
163 Result += "uwtable ";
164 if (hasAttribute(Attributes::ReturnsTwice))
165 Result += "returns_twice ";
166 if (hasAttribute(Attributes::InReg))
168 if (hasAttribute(Attributes::NoAlias))
169 Result += "noalias ";
170 if (hasAttribute(Attributes::NoCapture))
171 Result += "nocapture ";
172 if (hasAttribute(Attributes::StructRet))
174 if (hasAttribute(Attributes::ByVal))
176 if (hasAttribute(Attributes::Nest))
178 if (hasAttribute(Attributes::ReadNone))
179 Result += "readnone ";
180 if (hasAttribute(Attributes::ReadOnly))
181 Result += "readonly ";
182 if (hasAttribute(Attributes::OptimizeForSize))
183 Result += "optsize ";
184 if (hasAttribute(Attributes::NoInline))
185 Result += "noinline ";
186 if (hasAttribute(Attributes::InlineHint))
187 Result += "inlinehint ";
188 if (hasAttribute(Attributes::AlwaysInline))
189 Result += "alwaysinline ";
190 if (hasAttribute(Attributes::StackProtect))
192 if (hasAttribute(Attributes::StackProtectReq))
194 if (hasAttribute(Attributes::NoRedZone))
195 Result += "noredzone ";
196 if (hasAttribute(Attributes::NoImplicitFloat))
197 Result += "noimplicitfloat ";
198 if (hasAttribute(Attributes::Naked))
200 if (hasAttribute(Attributes::NonLazyBind))
201 Result += "nonlazybind ";
202 if (hasAttribute(Attributes::AddressSafety))
203 Result += "address_safety ";
204 if (hasAttribute(Attributes::MinSize))
205 Result += "minsize ";
206 if (hasAttribute(Attributes::StackAlignment)) {
207 Result += "alignstack(";
208 Result += utostr(getStackAlignment());
211 if (hasAttribute(Attributes::Alignment)) {
213 Result += utostr(getAlignment());
216 // Trim the trailing space.
217 assert(!Result.empty() && "Unknown attribute!");
218 Result.erase(Result.end()-1);
222 //===----------------------------------------------------------------------===//
223 // AttrBuilder Implementation
224 //===----------------------------------------------------------------------===//
226 AttrBuilder &AttrBuilder::addAttribute(Attributes::AttrVal Val){
227 Bits |= AttributesImpl::getAttrMask(Val);
231 AttrBuilder &AttrBuilder::addRawValue(uint64_t Val) {
236 AttrBuilder &AttrBuilder::addAlignmentAttr(unsigned Align) {
237 if (Align == 0) return *this;
238 assert(isPowerOf2_32(Align) && "Alignment must be a power of two.");
239 assert(Align <= 0x40000000 && "Alignment too large.");
240 Bits |= (Log2_32(Align) + 1) << 16;
243 AttrBuilder &AttrBuilder::addStackAlignmentAttr(unsigned Align){
244 // Default alignment, allow the target to define how to align it.
245 if (Align == 0) return *this;
246 assert(isPowerOf2_32(Align) && "Alignment must be a power of two.");
247 assert(Align <= 0x100 && "Alignment too large.");
248 Bits |= (Log2_32(Align) + 1) << 26;
252 AttrBuilder &AttrBuilder::removeAttribute(Attributes::AttrVal Val) {
253 Bits &= ~AttributesImpl::getAttrMask(Val);
257 AttrBuilder &AttrBuilder::addAttributes(const Attributes &A) {
262 AttrBuilder &AttrBuilder::removeAttributes(const Attributes &A){
267 bool AttrBuilder::hasAttribute(Attributes::AttrVal A) const {
268 return Bits & AttributesImpl::getAttrMask(A);
271 bool AttrBuilder::hasAttributes() const {
274 bool AttrBuilder::hasAttributes(const Attributes &A) const {
275 return Bits & A.Raw();
277 bool AttrBuilder::hasAlignmentAttr() const {
278 return Bits & AttributesImpl::getAttrMask(Attributes::Alignment);
281 uint64_t AttrBuilder::getAlignment() const {
282 if (!hasAlignmentAttr())
285 (((Bits & AttributesImpl::getAttrMask(Attributes::Alignment)) >> 16) - 1);
288 uint64_t AttrBuilder::getStackAlignment() const {
289 if (!hasAlignmentAttr())
292 (((Bits & AttributesImpl::getAttrMask(Attributes::StackAlignment))>>26)-1);
295 //===----------------------------------------------------------------------===//
296 // AttributeImpl Definition
297 //===----------------------------------------------------------------------===//
299 uint64_t AttributesImpl::getAttrMask(uint64_t Val) {
301 case Attributes::None: return 0;
302 case Attributes::ZExt: return 1 << 0;
303 case Attributes::SExt: return 1 << 1;
304 case Attributes::NoReturn: return 1 << 2;
305 case Attributes::InReg: return 1 << 3;
306 case Attributes::StructRet: return 1 << 4;
307 case Attributes::NoUnwind: return 1 << 5;
308 case Attributes::NoAlias: return 1 << 6;
309 case Attributes::ByVal: return 1 << 7;
310 case Attributes::Nest: return 1 << 8;
311 case Attributes::ReadNone: return 1 << 9;
312 case Attributes::ReadOnly: return 1 << 10;
313 case Attributes::NoInline: return 1 << 11;
314 case Attributes::AlwaysInline: return 1 << 12;
315 case Attributes::OptimizeForSize: return 1 << 13;
316 case Attributes::StackProtect: return 1 << 14;
317 case Attributes::StackProtectReq: return 1 << 15;
318 case Attributes::Alignment: return 31 << 16;
319 case Attributes::NoCapture: return 1 << 21;
320 case Attributes::NoRedZone: return 1 << 22;
321 case Attributes::NoImplicitFloat: return 1 << 23;
322 case Attributes::Naked: return 1 << 24;
323 case Attributes::InlineHint: return 1 << 25;
324 case Attributes::StackAlignment: return 7 << 26;
325 case Attributes::ReturnsTwice: return 1 << 29;
326 case Attributes::UWTable: return 1 << 30;
327 case Attributes::NonLazyBind: return 1U << 31;
328 case Attributes::AddressSafety: return 1ULL << 32;
329 case Attributes::MinSize: return 1ULL << 33;
331 llvm_unreachable("Unsupported attribute type");
334 bool AttributesImpl::hasAttribute(uint64_t A) const {
335 return (Bits & getAttrMask(A)) != 0;
338 bool AttributesImpl::hasAttributes() const {
342 bool AttributesImpl::hasAttributes(const Attributes &A) const {
343 return Bits & A.Raw(); // FIXME: Raw() won't work here in the future.
346 uint64_t AttributesImpl::getAlignment() const {
347 return Bits & getAttrMask(Attributes::Alignment);
350 uint64_t AttributesImpl::getStackAlignment() const {
351 return Bits & getAttrMask(Attributes::StackAlignment);
354 //===----------------------------------------------------------------------===//
355 // AttributeListImpl Definition
356 //===----------------------------------------------------------------------===//
359 class AttributeListImpl;
362 static ManagedStatic<FoldingSet<AttributeListImpl> > AttributesLists;
365 static ManagedStatic<sys::SmartMutex<true> > ALMutex;
367 class AttributeListImpl : public FoldingSetNode {
368 sys::cas_flag RefCount;
370 // AttributesList is uniqued, these should not be publicly available.
371 void operator=(const AttributeListImpl &) LLVM_DELETED_FUNCTION;
372 AttributeListImpl(const AttributeListImpl &) LLVM_DELETED_FUNCTION;
373 ~AttributeListImpl(); // Private implementation
375 SmallVector<AttributeWithIndex, 4> Attrs;
377 AttributeListImpl(ArrayRef<AttributeWithIndex> attrs)
378 : Attrs(attrs.begin(), attrs.end()) {
383 sys::SmartScopedLock<true> Lock(*ALMutex);
387 sys::SmartScopedLock<true> Lock(*ALMutex);
388 if (!AttributesLists.isConstructed())
390 sys::cas_flag new_val = --RefCount;
395 void Profile(FoldingSetNodeID &ID) const {
398 static void Profile(FoldingSetNodeID &ID, ArrayRef<AttributeWithIndex> Attrs){
399 for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
400 ID.AddInteger(Attrs[i].Attrs.Raw());
401 ID.AddInteger(Attrs[i].Index);
406 } // end llvm namespace
408 AttributeListImpl::~AttributeListImpl() {
409 // NOTE: Lock must be acquired by caller.
410 AttributesLists->RemoveNode(this);
413 AttrListPtr AttrListPtr::get(ArrayRef<AttributeWithIndex> Attrs) {
414 // If there are no attributes then return a null AttributesList pointer.
416 return AttrListPtr();
419 for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
420 assert(Attrs[i].Attrs.hasAttributes() &&
421 "Pointless attribute!");
422 assert((!i || Attrs[i-1].Index < Attrs[i].Index) &&
423 "Misordered AttributesList!");
427 // Otherwise, build a key to look up the existing attributes.
429 AttributeListImpl::Profile(ID, Attrs);
432 sys::SmartScopedLock<true> Lock(*ALMutex);
434 AttributeListImpl *PAL =
435 AttributesLists->FindNodeOrInsertPos(ID, InsertPos);
437 // If we didn't find any existing attributes of the same shape then
438 // create a new one and insert it.
440 PAL = new AttributeListImpl(Attrs);
441 AttributesLists->InsertNode(PAL, InsertPos);
444 // Return the AttributesList that we found or created.
445 return AttrListPtr(PAL);
448 //===----------------------------------------------------------------------===//
449 // AttrListPtr Method Implementations
450 //===----------------------------------------------------------------------===//
452 AttrListPtr::AttrListPtr(AttributeListImpl *LI) : AttrList(LI) {
453 if (LI) LI->AddRef();
456 AttrListPtr::AttrListPtr(const AttrListPtr &P) : AttrList(P.AttrList) {
457 if (AttrList) AttrList->AddRef();
460 const AttrListPtr &AttrListPtr::operator=(const AttrListPtr &RHS) {
461 sys::SmartScopedLock<true> Lock(*ALMutex);
462 if (AttrList == RHS.AttrList) return *this;
463 if (AttrList) AttrList->DropRef();
464 AttrList = RHS.AttrList;
465 if (AttrList) AttrList->AddRef();
469 AttrListPtr::~AttrListPtr() {
470 if (AttrList) AttrList->DropRef();
473 /// getNumSlots - Return the number of slots used in this attribute list.
474 /// This is the number of arguments that have an attribute set on them
475 /// (including the function itself).
476 unsigned AttrListPtr::getNumSlots() const {
477 return AttrList ? AttrList->Attrs.size() : 0;
480 /// getSlot - Return the AttributeWithIndex at the specified slot. This
481 /// holds a number plus a set of attributes.
482 const AttributeWithIndex &AttrListPtr::getSlot(unsigned Slot) const {
483 assert(AttrList && Slot < AttrList->Attrs.size() && "Slot # out of range!");
484 return AttrList->Attrs[Slot];
487 /// getAttributes - The attributes for the specified index are returned.
488 /// Attributes for the result are denoted with Idx = 0. Function notes are
489 /// denoted with idx = ~0.
490 Attributes AttrListPtr::getAttributes(unsigned Idx) const {
491 if (AttrList == 0) return Attributes();
493 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs;
494 for (unsigned i = 0, e = Attrs.size(); i != e && Attrs[i].Index <= Idx; ++i)
495 if (Attrs[i].Index == Idx)
496 return Attrs[i].Attrs;
501 /// hasAttrSomewhere - Return true if the specified attribute is set for at
502 /// least one parameter or for the return value.
503 bool AttrListPtr::hasAttrSomewhere(Attributes::AttrVal Attr) const {
504 if (AttrList == 0) return false;
506 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs;
507 for (unsigned i = 0, e = Attrs.size(); i != e; ++i)
508 if (Attrs[i].Attrs.hasAttribute(Attr))
513 unsigned AttrListPtr::getNumAttrs() const {
514 return AttrList ? AttrList->Attrs.size() : 0;
517 Attributes &AttrListPtr::getAttributesAtIndex(unsigned i) const {
518 assert(AttrList && "Trying to get an attribute from an empty list!");
519 assert(i < AttrList->Attrs.size() && "Index out of range!");
520 return AttrList->Attrs[i].Attrs;
523 AttrListPtr AttrListPtr::addAttr(LLVMContext &C, unsigned Idx,
524 Attributes Attrs) const {
525 Attributes OldAttrs = getAttributes(Idx);
527 // FIXME it is not obvious how this should work for alignment.
528 // For now, say we can't change a known alignment.
529 unsigned OldAlign = OldAttrs.getAlignment();
530 unsigned NewAlign = Attrs.getAlignment();
531 assert((!OldAlign || !NewAlign || OldAlign == NewAlign) &&
532 "Attempt to change alignment!");
535 AttrBuilder NewAttrs =
536 AttrBuilder(OldAttrs).addAttributes(Attrs);
537 if (NewAttrs == AttrBuilder(OldAttrs))
540 SmallVector<AttributeWithIndex, 8> NewAttrList;
542 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
544 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs;
545 unsigned i = 0, e = OldAttrList.size();
546 // Copy attributes for arguments before this one.
547 for (; i != e && OldAttrList[i].Index < Idx; ++i)
548 NewAttrList.push_back(OldAttrList[i]);
550 // If there are attributes already at this index, merge them in.
551 if (i != e && OldAttrList[i].Index == Idx) {
553 Attributes::get(C, AttrBuilder(Attrs).
554 addAttributes(OldAttrList[i].Attrs));
558 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
560 // Copy attributes for arguments after this one.
561 NewAttrList.insert(NewAttrList.end(),
562 OldAttrList.begin()+i, OldAttrList.end());
565 return get(NewAttrList);
568 AttrListPtr AttrListPtr::removeAttr(LLVMContext &C, unsigned Idx,
569 Attributes Attrs) const {
571 // FIXME it is not obvious how this should work for alignment.
572 // For now, say we can't pass in alignment, which no current use does.
573 assert(!Attrs.hasAttribute(Attributes::Alignment) &&
574 "Attempt to exclude alignment!");
576 if (AttrList == 0) return AttrListPtr();
578 Attributes OldAttrs = getAttributes(Idx);
579 AttrBuilder NewAttrs =
580 AttrBuilder(OldAttrs).removeAttributes(Attrs);
581 if (NewAttrs == AttrBuilder(OldAttrs))
584 SmallVector<AttributeWithIndex, 8> NewAttrList;
585 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs;
586 unsigned i = 0, e = OldAttrList.size();
588 // Copy attributes for arguments before this one.
589 for (; i != e && OldAttrList[i].Index < Idx; ++i)
590 NewAttrList.push_back(OldAttrList[i]);
592 // If there are attributes already at this index, merge them in.
593 assert(OldAttrList[i].Index == Idx && "Attribute isn't set?");
594 Attrs = Attributes::get(C, AttrBuilder(OldAttrList[i].Attrs).
595 removeAttributes(Attrs));
597 if (Attrs.hasAttributes()) // If any attributes left for this param, add them.
598 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
600 // Copy attributes for arguments after this one.
601 NewAttrList.insert(NewAttrList.end(),
602 OldAttrList.begin()+i, OldAttrList.end());
604 return get(NewAttrList);
607 void AttrListPtr::dump() const {
609 for (unsigned i = 0; i < getNumSlots(); ++i) {
610 const AttributeWithIndex &PAWI = getSlot(i);
611 dbgs() << "{" << PAWI.Index << "," << PAWI.Attrs.getAsString() << "} ";