1 //===-- Attribute.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 Attribute, AttributeImpl, AttrBuilder,
11 // AttributeSetImpl, and AttributeSet classes.
13 //===----------------------------------------------------------------------===//
15 #include "llvm/Attributes.h"
16 #include "AttributeImpl.h"
17 #include "LLVMContextImpl.h"
18 #include "llvm/ADT/FoldingSet.h"
19 #include "llvm/ADT/StringExtras.h"
20 #include "llvm/Support/Atomic.h"
21 #include "llvm/Support/Debug.h"
22 #include "llvm/Support/ManagedStatic.h"
23 #include "llvm/Support/Mutex.h"
24 #include "llvm/Support/raw_ostream.h"
25 #include "llvm/Type.h"
28 //===----------------------------------------------------------------------===//
29 // Attribute Implementation
30 //===----------------------------------------------------------------------===//
32 Attribute Attribute::get(LLVMContext &Context, ArrayRef<AttrKind> Vals) {
34 for (ArrayRef<AttrKind>::iterator I = Vals.begin(), E = Vals.end();
37 return Attribute::get(Context, B);
40 Attribute Attribute::get(LLVMContext &Context, AttrBuilder &B) {
41 // If there are no attributes, return an empty Attribute 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.getBitMask());
51 AttributeImpl *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 AttributeImpl(Context, B.getBitMask());
57 pImpl->AttrsSet.InsertNode(PA, InsertPoint);
60 // Return the AttributesList that we found or created.
64 bool Attribute::hasAttribute(AttrKind Val) const {
65 return pImpl && pImpl->hasAttribute(Val);
68 bool Attribute::hasAttributes() const {
69 return pImpl && pImpl->hasAttributes();
72 bool Attribute::hasAttributes(const Attribute &A) const {
73 return pImpl && pImpl->hasAttributes(A);
76 /// This returns the alignment field of an attribute as a byte alignment value.
77 unsigned Attribute::getAlignment() const {
78 if (!hasAttribute(Attribute::Alignment))
80 return 1U << ((pImpl->getAlignment() >> 16) - 1);
83 /// This returns the stack alignment field of an attribute as a byte alignment
85 unsigned Attribute::getStackAlignment() const {
86 if (!hasAttribute(Attribute::StackAlignment))
88 return 1U << ((pImpl->getStackAlignment() >> 26) - 1);
91 uint64_t Attribute::getBitMask() const {
92 return pImpl ? pImpl->getBitMask() : 0;
95 Attribute Attribute::typeIncompatible(Type *Ty) {
96 AttrBuilder Incompatible;
98 if (!Ty->isIntegerTy())
99 // Attribute that only apply to integers.
100 Incompatible.addAttribute(Attribute::SExt)
101 .addAttribute(Attribute::ZExt);
103 if (!Ty->isPointerTy())
104 // Attribute that only apply to pointers.
105 Incompatible.addAttribute(Attribute::ByVal)
106 .addAttribute(Attribute::Nest)
107 .addAttribute(Attribute::NoAlias)
108 .addAttribute(Attribute::NoCapture)
109 .addAttribute(Attribute::StructRet);
111 return Attribute::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 Attribute::encodeLLVMAttributesForBitcode(Attribute 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.getBitMask() & 0xffff;
128 if (Attrs.hasAttribute(Attribute::Alignment))
129 EncodedAttrs |= Attrs.getAlignment() << 16;
130 EncodedAttrs |= (Attrs.getBitMask() & (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 Attribute Attribute::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 Attribute::get(C, B);
152 std::string Attribute::getAsString() const {
154 if (hasAttribute(Attribute::ZExt))
155 Result += "zeroext ";
156 if (hasAttribute(Attribute::SExt))
157 Result += "signext ";
158 if (hasAttribute(Attribute::NoReturn))
159 Result += "noreturn ";
160 if (hasAttribute(Attribute::NoUnwind))
161 Result += "nounwind ";
162 if (hasAttribute(Attribute::UWTable))
163 Result += "uwtable ";
164 if (hasAttribute(Attribute::ReturnsTwice))
165 Result += "returns_twice ";
166 if (hasAttribute(Attribute::InReg))
168 if (hasAttribute(Attribute::NoAlias))
169 Result += "noalias ";
170 if (hasAttribute(Attribute::NoCapture))
171 Result += "nocapture ";
172 if (hasAttribute(Attribute::StructRet))
174 if (hasAttribute(Attribute::ByVal))
176 if (hasAttribute(Attribute::Nest))
178 if (hasAttribute(Attribute::ReadNone))
179 Result += "readnone ";
180 if (hasAttribute(Attribute::ReadOnly))
181 Result += "readonly ";
182 if (hasAttribute(Attribute::OptimizeForSize))
183 Result += "optsize ";
184 if (hasAttribute(Attribute::NoInline))
185 Result += "noinline ";
186 if (hasAttribute(Attribute::InlineHint))
187 Result += "inlinehint ";
188 if (hasAttribute(Attribute::AlwaysInline))
189 Result += "alwaysinline ";
190 if (hasAttribute(Attribute::StackProtect))
192 if (hasAttribute(Attribute::StackProtectReq))
194 if (hasAttribute(Attribute::NoRedZone))
195 Result += "noredzone ";
196 if (hasAttribute(Attribute::NoImplicitFloat))
197 Result += "noimplicitfloat ";
198 if (hasAttribute(Attribute::Naked))
200 if (hasAttribute(Attribute::NonLazyBind))
201 Result += "nonlazybind ";
202 if (hasAttribute(Attribute::AddressSafety))
203 Result += "address_safety ";
204 if (hasAttribute(Attribute::MinSize))
205 Result += "minsize ";
206 if (hasAttribute(Attribute::StackAlignment)) {
207 Result += "alignstack(";
208 Result += utostr(getStackAlignment());
211 if (hasAttribute(Attribute::Alignment)) {
213 Result += utostr(getAlignment());
216 if (hasAttribute(Attribute::NoDuplicate))
217 Result += "noduplicate ";
218 // Trim the trailing space.
219 assert(!Result.empty() && "Unknown attribute!");
220 Result.erase(Result.end()-1);
224 //===----------------------------------------------------------------------===//
225 // AttrBuilder Implementation
226 //===----------------------------------------------------------------------===//
228 AttrBuilder &AttrBuilder::addAttribute(Attribute::AttrKind Val){
229 Bits |= AttributeImpl::getAttrMask(Val);
233 AttrBuilder &AttrBuilder::addRawValue(uint64_t Val) {
238 AttrBuilder &AttrBuilder::addAlignmentAttr(unsigned Align) {
239 if (Align == 0) return *this;
240 assert(isPowerOf2_32(Align) && "Alignment must be a power of two.");
241 assert(Align <= 0x40000000 && "Alignment too large.");
242 Bits |= (Log2_32(Align) + 1) << 16;
245 AttrBuilder &AttrBuilder::addStackAlignmentAttr(unsigned Align){
246 // Default alignment, allow the target to define how to align it.
247 if (Align == 0) return *this;
248 assert(isPowerOf2_32(Align) && "Alignment must be a power of two.");
249 assert(Align <= 0x100 && "Alignment too large.");
250 Bits |= (Log2_32(Align) + 1) << 26;
254 AttrBuilder &AttrBuilder::removeAttribute(Attribute::AttrKind Val) {
255 Bits &= ~AttributeImpl::getAttrMask(Val);
259 AttrBuilder &AttrBuilder::addAttributes(const Attribute &A) {
260 Bits |= A.getBitMask();
264 AttrBuilder &AttrBuilder::removeAttributes(const Attribute &A){
265 Bits &= ~A.getBitMask();
269 bool AttrBuilder::hasAttribute(Attribute::AttrKind A) const {
270 return Bits & AttributeImpl::getAttrMask(A);
273 bool AttrBuilder::hasAttributes() const {
276 bool AttrBuilder::hasAttributes(const Attribute &A) const {
277 return Bits & A.getBitMask();
279 bool AttrBuilder::hasAlignmentAttr() const {
280 return Bits & AttributeImpl::getAttrMask(Attribute::Alignment);
283 uint64_t AttrBuilder::getAlignment() const {
284 if (!hasAlignmentAttr())
287 (((Bits & AttributeImpl::getAttrMask(Attribute::Alignment)) >> 16) - 1);
290 uint64_t AttrBuilder::getStackAlignment() const {
291 if (!hasAlignmentAttr())
294 (((Bits & AttributeImpl::getAttrMask(Attribute::StackAlignment))>>26)-1);
297 //===----------------------------------------------------------------------===//
298 // AttributeImpl Definition
299 //===----------------------------------------------------------------------===//
301 AttributeImpl::AttributeImpl(LLVMContext &C, uint64_t data) {
302 Data = ConstantInt::get(Type::getInt64Ty(C), data);
305 uint64_t AttributeImpl::getBitMask() const {
306 return cast<ConstantInt>(Data)->getZExtValue();
309 uint64_t AttributeImpl::getAttrMask(uint64_t Val) {
311 case Attribute::None: return 0;
312 case Attribute::ZExt: return 1 << 0;
313 case Attribute::SExt: return 1 << 1;
314 case Attribute::NoReturn: return 1 << 2;
315 case Attribute::InReg: return 1 << 3;
316 case Attribute::StructRet: return 1 << 4;
317 case Attribute::NoUnwind: return 1 << 5;
318 case Attribute::NoAlias: return 1 << 6;
319 case Attribute::ByVal: return 1 << 7;
320 case Attribute::Nest: return 1 << 8;
321 case Attribute::ReadNone: return 1 << 9;
322 case Attribute::ReadOnly: return 1 << 10;
323 case Attribute::NoInline: return 1 << 11;
324 case Attribute::AlwaysInline: return 1 << 12;
325 case Attribute::OptimizeForSize: return 1 << 13;
326 case Attribute::StackProtect: return 1 << 14;
327 case Attribute::StackProtectReq: return 1 << 15;
328 case Attribute::Alignment: return 31 << 16;
329 case Attribute::NoCapture: return 1 << 21;
330 case Attribute::NoRedZone: return 1 << 22;
331 case Attribute::NoImplicitFloat: return 1 << 23;
332 case Attribute::Naked: return 1 << 24;
333 case Attribute::InlineHint: return 1 << 25;
334 case Attribute::StackAlignment: return 7 << 26;
335 case Attribute::ReturnsTwice: return 1 << 29;
336 case Attribute::UWTable: return 1 << 30;
337 case Attribute::NonLazyBind: return 1U << 31;
338 case Attribute::AddressSafety: return 1ULL << 32;
339 case Attribute::MinSize: return 1ULL << 33;
340 case Attribute::NoDuplicate: return 1ULL << 34;
342 llvm_unreachable("Unsupported attribute type");
345 bool AttributeImpl::hasAttribute(uint64_t A) const {
346 return (getBitMask() & getAttrMask(A)) != 0;
349 bool AttributeImpl::hasAttributes() const {
350 return getBitMask() != 0;
353 bool AttributeImpl::hasAttributes(const Attribute &A) const {
354 // FIXME: getBitMask() won't work here in the future.
355 return getBitMask() & A.getBitMask();
358 uint64_t AttributeImpl::getAlignment() const {
359 return getBitMask() & getAttrMask(Attribute::Alignment);
362 uint64_t AttributeImpl::getStackAlignment() const {
363 return getBitMask() & getAttrMask(Attribute::StackAlignment);
366 void AttributeImpl::Profile(FoldingSetNodeID &ID, Constant *Data) {
367 ID.AddInteger(cast<ConstantInt>(Data)->getZExtValue());
370 //===----------------------------------------------------------------------===//
371 // AttributeSetImpl Definition
372 //===----------------------------------------------------------------------===//
374 AttributeSet AttributeSet::get(LLVMContext &C,
375 ArrayRef<AttributeWithIndex> Attrs) {
376 // If there are no attributes then return a null AttributesList pointer.
378 return AttributeSet();
381 for (unsigned i = 0, e = Attrs.size(); i != e; ++i) {
382 assert(Attrs[i].Attrs.hasAttributes() &&
383 "Pointless attribute!");
384 assert((!i || Attrs[i-1].Index < Attrs[i].Index) &&
385 "Misordered AttributesList!");
389 // Otherwise, build a key to look up the existing attributes.
390 LLVMContextImpl *pImpl = C.pImpl;
392 AttributeSetImpl::Profile(ID, Attrs);
395 AttributeSetImpl *PA = pImpl->AttrsLists.FindNodeOrInsertPos(ID,
398 // If we didn't find any existing attributes of the same shape then
399 // create a new one and insert it.
401 PA = new AttributeSetImpl(C, Attrs);
402 pImpl->AttrsLists.InsertNode(PA, InsertPoint);
405 // Return the AttributesList that we found or created.
406 return AttributeSet(PA);
409 //===----------------------------------------------------------------------===//
410 // AttributeSet Method Implementations
411 //===----------------------------------------------------------------------===//
413 const AttributeSet &AttributeSet::operator=(const AttributeSet &RHS) {
414 AttrList = RHS.AttrList;
418 /// getNumSlots - Return the number of slots used in this attribute list.
419 /// This is the number of arguments that have an attribute set on them
420 /// (including the function itself).
421 unsigned AttributeSet::getNumSlots() const {
422 return AttrList ? AttrList->Attrs.size() : 0;
425 /// getSlot - Return the AttributeWithIndex at the specified slot. This
426 /// holds a number plus a set of attributes.
427 const AttributeWithIndex &AttributeSet::getSlot(unsigned Slot) const {
428 assert(AttrList && Slot < AttrList->Attrs.size() && "Slot # out of range!");
429 return AttrList->Attrs[Slot];
432 /// getAttributes - The attributes for the specified index are returned.
433 /// Attribute for the result are denoted with Idx = 0. Function notes are
434 /// denoted with idx = ~0.
435 Attribute AttributeSet::getAttributes(unsigned Idx) const {
436 if (AttrList == 0) return Attribute();
438 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs;
439 for (unsigned i = 0, e = Attrs.size(); i != e && Attrs[i].Index <= Idx; ++i)
440 if (Attrs[i].Index == Idx)
441 return Attrs[i].Attrs;
446 /// hasAttrSomewhere - Return true if the specified attribute is set for at
447 /// least one parameter or for the return value.
448 bool AttributeSet::hasAttrSomewhere(Attribute::AttrKind Attr) const {
449 if (AttrList == 0) return false;
451 const SmallVector<AttributeWithIndex, 4> &Attrs = AttrList->Attrs;
452 for (unsigned i = 0, e = Attrs.size(); i != e; ++i)
453 if (Attrs[i].Attrs.hasAttribute(Attr))
459 unsigned AttributeSet::getNumAttrs() const {
460 return AttrList ? AttrList->Attrs.size() : 0;
463 Attribute &AttributeSet::getAttributesAtIndex(unsigned i) const {
464 assert(AttrList && "Trying to get an attribute from an empty list!");
465 assert(i < AttrList->Attrs.size() && "Index out of range!");
466 return AttrList->Attrs[i].Attrs;
469 AttributeSet AttributeSet::addAttr(LLVMContext &C, unsigned Idx,
470 Attribute Attrs) const {
471 Attribute OldAttrs = getAttributes(Idx);
473 // FIXME it is not obvious how this should work for alignment.
474 // For now, say we can't change a known alignment.
475 unsigned OldAlign = OldAttrs.getAlignment();
476 unsigned NewAlign = Attrs.getAlignment();
477 assert((!OldAlign || !NewAlign || OldAlign == NewAlign) &&
478 "Attempt to change alignment!");
481 AttrBuilder NewAttrs =
482 AttrBuilder(OldAttrs).addAttributes(Attrs);
483 if (NewAttrs == AttrBuilder(OldAttrs))
486 SmallVector<AttributeWithIndex, 8> NewAttrList;
488 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
490 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs;
491 unsigned i = 0, e = OldAttrList.size();
492 // Copy attributes for arguments before this one.
493 for (; i != e && OldAttrList[i].Index < Idx; ++i)
494 NewAttrList.push_back(OldAttrList[i]);
496 // If there are attributes already at this index, merge them in.
497 if (i != e && OldAttrList[i].Index == Idx) {
499 Attribute::get(C, AttrBuilder(Attrs).
500 addAttributes(OldAttrList[i].Attrs));
504 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
506 // Copy attributes for arguments after this one.
507 NewAttrList.insert(NewAttrList.end(),
508 OldAttrList.begin()+i, OldAttrList.end());
511 return get(C, NewAttrList);
514 AttributeSet AttributeSet::removeAttr(LLVMContext &C, unsigned Idx,
515 Attribute Attrs) const {
517 // FIXME it is not obvious how this should work for alignment.
518 // For now, say we can't pass in alignment, which no current use does.
519 assert(!Attrs.hasAttribute(Attribute::Alignment) &&
520 "Attempt to exclude alignment!");
522 if (AttrList == 0) return AttributeSet();
524 Attribute OldAttrs = getAttributes(Idx);
525 AttrBuilder NewAttrs =
526 AttrBuilder(OldAttrs).removeAttributes(Attrs);
527 if (NewAttrs == AttrBuilder(OldAttrs))
530 SmallVector<AttributeWithIndex, 8> NewAttrList;
531 const SmallVector<AttributeWithIndex, 4> &OldAttrList = AttrList->Attrs;
532 unsigned i = 0, e = OldAttrList.size();
534 // Copy attributes for arguments before this one.
535 for (; i != e && OldAttrList[i].Index < Idx; ++i)
536 NewAttrList.push_back(OldAttrList[i]);
538 // If there are attributes already at this index, merge them in.
539 assert(OldAttrList[i].Index == Idx && "Attribute isn't set?");
540 Attrs = Attribute::get(C, AttrBuilder(OldAttrList[i].Attrs).
541 removeAttributes(Attrs));
543 if (Attrs.hasAttributes()) // If any attributes left for this param, add them.
544 NewAttrList.push_back(AttributeWithIndex::get(Idx, Attrs));
546 // Copy attributes for arguments after this one.
547 NewAttrList.insert(NewAttrList.end(),
548 OldAttrList.begin()+i, OldAttrList.end());
550 return get(C, NewAttrList);
553 void AttributeSet::dump() const {
555 for (unsigned i = 0; i < getNumSlots(); ++i) {
556 const AttributeWithIndex &PAWI = getSlot(i);
557 dbgs() << "{" << PAWI.Index << "," << PAWI.Attrs.getAsString() << "} ";