X-Git-Url: http://demsky.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FAttributes.h;h=d04ca590aaa875991859d22486c91639230a557e;hb=5a0eeb5a9d727940b1dbe8dff6e9aa292ada0f6a;hp=ab093788f7a1d941b36187fcea689fdce664001e;hpb=f23d0d392ab47e191e1bbd17dc7487b9d461485c;p=oota-llvm.git diff --git a/include/llvm/Attributes.h b/include/llvm/Attributes.h index ab093788f7a..d04ca590aaa 100644 --- a/include/llvm/Attributes.h +++ b/include/llvm/Attributes.h @@ -1,4 +1,4 @@ -//===-- llvm/Attributes.h - Container for Attributes ---*---------- C++ -*-===// +//===-- llvm/Attributes.h - Container for Attributes ------------*- C++ -*-===// // // The LLVM Compiler Infrastructure // @@ -16,93 +16,323 @@ #define LLVM_ATTRIBUTES_H #include "llvm/Support/MathExtras.h" +#include "llvm/ADT/ArrayRef.h" #include #include namespace llvm { + +class LLVMContext; class Type; +/// AttributeImpl - The internal representation of the Attributes class. This is +/// uniquified. +class AttributesImpl; + /// Attributes - A bitset of attributes. -typedef unsigned Attributes; - -namespace Attribute { - -/// Function parameters and results can have attributes to indicate how they -/// should be treated by optimizations and code generation. This enumeration -/// lists the attributes that can be associated with parameters, function -/// results or the function itself. -/// @brief Function attributes. - -const Attributes None = 0; ///< No attributes have been set -const Attributes ZExt = 1<<0; ///< Zero extended before/after call -const Attributes SExt = 1<<1; ///< Sign extended before/after call -const Attributes NoReturn = 1<<2; ///< Mark the function as not returning -const Attributes InReg = 1<<3; ///< Force argument to be passed in register -const Attributes StructRet = 1<<4; ///< Hidden pointer to structure to return -const Attributes NoUnwind = 1<<5; ///< Function doesn't unwind stack -const Attributes NoAlias = 1<<6; ///< Considered to not alias after call -const Attributes ByVal = 1<<7; ///< Pass structure by value -const Attributes Nest = 1<<8; ///< Nested function static chain -const Attributes ReadNone = 1<<9; ///< Function does not access memory -const Attributes ReadOnly = 1<<10; ///< Function only reads from memory -const Attributes NoInline = 1<<11; ///< inline=never -const Attributes AlwaysInline = 1<<12; ///< inline=always -const Attributes OptimizeForSize = 1<<13; ///< opt_size -const Attributes StackProtect = 1<<14; ///< Stack protection. -const Attributes StackProtectReq = 1<<15; ///< Stack protection required. -const Attributes Alignment = 31<<16; ///< Alignment of parameter (5 bits) - // stored as log2 of alignment with +1 bias - // 0 means unaligned different from align 1 -const Attributes NoCapture = 1<<21; ///< Function creates no aliases of pointer - -/// @brief Attributes that only apply to function parameters. -const Attributes ParameterOnly = ByVal | Nest | StructRet | NoCapture; - -/// @brief Attributes that only apply to function. -const Attributes FunctionOnly = NoReturn | NoUnwind | ReadNone | ReadOnly | - NoInline | AlwaysInline | OptimizeForSize | StackProtect | StackProtectReq; - -/// @brief Parameter attributes that do not apply to vararg call arguments. -const Attributes VarArgsIncompatible = StructRet; - -/// @brief Attributes that are mutually incompatible. -const Attributes MutuallyIncompatible[4] = { - ByVal | InReg | Nest | StructRet, - ZExt | SExt, - ReadNone | ReadOnly, - NoInline | AlwaysInline +class Attributes { +public: + /// Function parameters and results can have attributes to indicate how they + /// should be treated by optimizations and code generation. This enumeration + /// lists the attributes that can be associated with parameters, function + /// results or the function itself. + /// + /// Note that uwtable is about the ABI or the user mandating an entry in the + /// unwind table. The nounwind attribute is about an exception passing by the + /// function. + /// + /// In a theoretical system that uses tables for profiling and sjlj for + /// exceptions, they would be fully independent. In a normal system that uses + /// tables for both, the semantics are: + /// + /// nil = Needs an entry because an exception might pass by. + /// nounwind = No need for an entry + /// uwtable = Needs an entry because the ABI says so and because + /// an exception might pass by. + /// uwtable + nounwind = Needs an entry because the ABI says so. + + enum AttrVal { + // IR-Level Attributes + None = 0, ///< No attributes have been set + AddressSafety = 1, ///< Address safety checking is on. + Alignment = 2, ///< Alignment of parameter (5 bits) + ///< stored as log2 of alignment with +1 bias + ///< 0 means unaligned different from align 1 + AlwaysInline = 3, ///< inline=always + ByVal = 4, ///< Pass structure by value + InlineHint = 5, ///< Source said inlining was desirable + InReg = 6, ///< Force argument to be passed in register + Naked = 7, ///< Naked function + Nest = 8, ///< Nested function static chain + NoAlias = 9, ///< Considered to not alias after call + NoCapture = 10, ///< Function creates no aliases of pointer + NoImplicitFloat = 11, ///< Disable implicit floating point insts + NoInline = 12, ///< inline=never + NonLazyBind = 13, ///< Function is called early and/or + ///< often, so lazy binding isn't worthwhile + NoRedZone = 14, ///< Disable redzone + NoReturn = 15, ///< Mark the function as not returning + NoUnwind = 16, ///< Function doesn't unwind stack + OptimizeForSize = 17, ///< opt_size + ReadNone = 18, ///< Function does not access memory + ReadOnly = 19, ///< Function only reads from memory + ReturnsTwice = 20, ///< Function can return twice + SExt = 21, ///< Sign extended before/after call + StackAlignment = 22, ///< Alignment of stack for function (3 bits) + ///< stored as log2 of alignment with +1 bias 0 + ///< means unaligned (different from + ///< alignstack={1)) + StackProtect = 23, ///< Stack protection. + StackProtectReq = 24, ///< Stack protection required. + StructRet = 25, ///< Hidden pointer to structure to return + UWTable = 26, ///< Function must be in a unwind table + ZExt = 27 ///< Zero extended before/after call + }; +private: + AttributesImpl *Attrs; + Attributes(AttributesImpl *A); +public: + Attributes() : Attrs(0) {} + Attributes(const Attributes &A); + Attributes &operator=(const Attributes &A) { + Attrs = A.Attrs; + return *this; + } + + /// get - Return a uniquified Attributes object. This takes the uniquified + /// value from the Builder and wraps it in the Attributes class. + class Builder; + static Attributes get(LLVMContext &Context, ArrayRef Vals); + static Attributes get(LLVMContext &Context, Builder &B); + + //===--------------------------------------------------------------------===// + /// Attributes::Builder - This class is used in conjunction with the + /// Attributes::get method to create an Attributes object. The object itself + /// is uniquified. The Builder's value, however, is not. So this can be used + /// as a quick way to test for equality, presence of attributes, etc. + class Builder { + friend class Attributes; + uint64_t Bits; + public: + Builder() : Bits(0) {} + explicit Builder(uint64_t B) : Bits(B) {} + Builder(const Attributes &A) : Bits(A.Raw()) {} + Builder(const Builder &B) : Bits(B.Bits) {} + + void clear() { Bits = 0; } + + /// addAttribute - Add an attribute to the builder. + Builder &addAttribute(Attributes::AttrVal Val); + + /// removeAttribute - Remove an attribute from the builder. + Builder &removeAttribute(Attributes::AttrVal Val); + + /// addAttribute - Add the attributes from A to the builder. + Builder &addAttributes(const Attributes &A); + + /// removeAttribute - Remove the attributes from A from the builder. + Builder &removeAttributes(const Attributes &A); + + /// hasAttribute - Return true if the builder has the specified attribute. + bool hasAttribute(Attributes::AttrVal A) const; + + /// hasAttributes - Return true if the builder has IR-level attributes. + bool hasAttributes() const; + + /// hasAttributes - Return true if the builder has any attribute that's in + /// the specified attribute. + bool hasAttributes(const Attributes &A) const; + + /// hasAlignmentAttr - Return true if the builder has an alignment + /// attribute. + bool hasAlignmentAttr() const; + + /// getAlignment - Retrieve the alignment attribute, if it exists. + uint64_t getAlignment() const; + + /// getStackAlignment - Retrieve the stack alignment attribute, if it + /// exists. + uint64_t getStackAlignment() const; + + /// addAlignmentAttr - This turns an int alignment (which must be a power of + /// 2) into the form used internally in Attributes. + Builder &addAlignmentAttr(unsigned Align); + + /// addStackAlignmentAttr - This turns an int stack alignment (which must be + /// a power of 2) into the form used internally in Attributes. + Builder &addStackAlignmentAttr(unsigned Align); + + /// addRawValue - Add the raw value to the internal representation. + /// N.B. This should be used ONLY for decoding LLVM bitcode! + Builder &addRawValue(uint64_t Val); + + /// @brief Remove attributes that are used on functions only. + void removeFunctionOnlyAttrs() { + removeAttribute(Attributes::NoReturn) + .removeAttribute(Attributes::NoUnwind) + .removeAttribute(Attributes::ReadNone) + .removeAttribute(Attributes::ReadOnly) + .removeAttribute(Attributes::NoInline) + .removeAttribute(Attributes::AlwaysInline) + .removeAttribute(Attributes::OptimizeForSize) + .removeAttribute(Attributes::StackProtect) + .removeAttribute(Attributes::StackProtectReq) + .removeAttribute(Attributes::NoRedZone) + .removeAttribute(Attributes::NoImplicitFloat) + .removeAttribute(Attributes::Naked) + .removeAttribute(Attributes::InlineHint) + .removeAttribute(Attributes::StackAlignment) + .removeAttribute(Attributes::UWTable) + .removeAttribute(Attributes::NonLazyBind) + .removeAttribute(Attributes::ReturnsTwice) + .removeAttribute(Attributes::AddressSafety); + } + + bool operator==(const Builder &B) { + return Bits == B.Bits; + } + bool operator!=(const Builder &B) { + return Bits != B.Bits; + } + }; + + /// @brief Return true if the attribute is present. + bool hasAttribute(AttrVal Val) const; + + /// @brief Return true if attributes exist + bool hasAttributes() const; + + /// @brief Return true if the attributes are a non-null intersection. + bool hasAttributes(const Attributes &A) const; + + /// @brief Returns the alignment field of an attribute as a byte alignment + /// value. + unsigned getAlignment() const; + + /// @brief Returns the stack alignment field of an attribute as a byte + /// alignment value. + unsigned getStackAlignment() const; + + /// @brief Parameter attributes that do not apply to vararg call arguments. + bool hasIncompatibleWithVarArgsAttrs() const { + return hasAttribute(Attributes::StructRet); + } + + /// @brief Attributes that only apply to function parameters. + bool hasParameterOnlyAttrs() const { + return hasAttribute(Attributes::ByVal) || + hasAttribute(Attributes::Nest) || + hasAttribute(Attributes::StructRet) || + hasAttribute(Attributes::NoCapture); + } + + /// @brief Attributes that may be applied to the function itself. These cannot + /// be used on return values or function parameters. + bool hasFunctionOnlyAttrs() const { + return hasAttribute(Attributes::NoReturn) || + hasAttribute(Attributes::NoUnwind) || + hasAttribute(Attributes::ReadNone) || + hasAttribute(Attributes::ReadOnly) || + hasAttribute(Attributes::NoInline) || + hasAttribute(Attributes::AlwaysInline) || + hasAttribute(Attributes::OptimizeForSize) || + hasAttribute(Attributes::StackProtect) || + hasAttribute(Attributes::StackProtectReq) || + hasAttribute(Attributes::NoRedZone) || + hasAttribute(Attributes::NoImplicitFloat) || + hasAttribute(Attributes::Naked) || + hasAttribute(Attributes::InlineHint) || + hasAttribute(Attributes::StackAlignment) || + hasAttribute(Attributes::UWTable) || + hasAttribute(Attributes::NonLazyBind) || + hasAttribute(Attributes::ReturnsTwice) || + hasAttribute(Attributes::AddressSafety); + } + + bool operator==(const Attributes &A) const { + return Attrs == A.Attrs; + } + bool operator!=(const Attributes &A) const { + return Attrs != A.Attrs; + } + + uint64_t Raw() const; + + /// @brief Which attributes cannot be applied to a type. + static Attributes typeIncompatible(Type *Ty); + + /// encodeLLVMAttributesForBitcode - This returns an integer containing an + /// encoding of all the LLVM attributes found in the given attribute bitset. + /// Any change to this encoding is a breaking change to bitcode compatibility. + static uint64_t encodeLLVMAttributesForBitcode(Attributes Attrs) { + // FIXME: It doesn't make sense to store the alignment information as an + // expanded out value, we should store it as a log2 value. However, we + // can't just change that here without breaking bitcode compatibility. If + // this ever becomes a problem in practice, we should introduce new tag + // numbers in the bitcode file and have those tags use a more efficiently + // encoded alignment field. + + // Store the alignment in the bitcode as a 16-bit raw value instead of a + // 5-bit log2 encoded value. Shift the bits above the alignment up by 11 + // bits. + uint64_t EncodedAttrs = Attrs.Raw() & 0xffff; + if (Attrs.hasAttribute(Attributes::Alignment)) + EncodedAttrs |= Attrs.getAlignment() << 16; + EncodedAttrs |= (Attrs.Raw() & (0xfffULL << 21)) << 11; + return EncodedAttrs; + } + + /// decodeLLVMAttributesForBitcode - This returns an attribute bitset + /// containing the LLVM attributes that have been decoded from the given + /// integer. This function must stay in sync with + /// 'encodeLLVMAttributesForBitcode'. + static Attributes decodeLLVMAttributesForBitcode(LLVMContext &C, + uint64_t EncodedAttrs) { + // The alignment is stored as a 16-bit raw value from bits 31--16. We shift + // the bits above 31 down by 11 bits. + unsigned Alignment = (EncodedAttrs & (0xffffULL << 16)) >> 16; + assert((!Alignment || isPowerOf2_32(Alignment)) && + "Alignment must be a power of two."); + + Attributes::Builder B(EncodedAttrs & 0xffff); + if (Alignment) + B.addAlignmentAttr(Alignment); + B.addRawValue((EncodedAttrs & (0xfffULL << 32)) >> 11); + return Attributes::get(C, B); + } + + /// getAsString - The set of Attributes set in Attributes is converted to a + /// string of equivalent mnemonics. This is, presumably, for writing out the + /// mnemonics for the assembly writer. + /// @brief Convert attribute bits to text + std::string getAsString() const; }; -/// @brief Which attributes cannot be applied to a type. -Attributes typeIncompatible(const Type *Ty); - -/// This turns an int alignment (a power of 2, normally) into the -/// form used internally in Attributes. -inline Attributes constructAlignmentFromInt(unsigned i) { - // Default alignment, allow the target to define how to align it. - if (i == 0) - return 0; - - assert(isPowerOf2_32(i) && "Alignment must be a power of two."); - assert(i <= 0x40000000 && "Alignment too large."); - return (Log2_32(i)+1) << 16; -} - -/// The set of Attributes set in Attributes is converted to a -/// string of equivalent mnemonics. This is, presumably, for writing out -/// the mnemonics for the assembly writer. -/// @brief Convert attribute bits to text -std::string getAsString(Attributes Attrs); -} // end namespace Attribute - -/// This is just a pair of values to associate a set of attributes -/// with an index. +//===----------------------------------------------------------------------===// +// AttributeWithIndex +//===----------------------------------------------------------------------===// + +/// AttributeWithIndex - This is just a pair of values to associate a set of +/// attributes with an index. struct AttributeWithIndex { - Attributes Attrs; ///< The attributes that are set, or'd together. - unsigned Index; ///< Index of the parameter for which the attributes apply. - ///< Index 0 is used for return value attributes. - ///< Index ~0U is used for function attributes. - + Attributes Attrs; ///< The attributes that are set, or'd together. + unsigned Index; ///< Index of the parameter for which the attributes apply. + ///< Index 0 is used for return value attributes. + ///< Index ~0U is used for function attributes. + + static AttributeWithIndex get(LLVMContext &C, unsigned Idx, + ArrayRef Attrs) { + Attributes::Builder B; + + for (ArrayRef::iterator I = Attrs.begin(), + E = Attrs.end(); I != E; ++I) + B.addAttribute(*I); + + AttributeWithIndex P; + P.Index = Idx; + P.Attrs = Attributes::get(C, B); + return P; + } static AttributeWithIndex get(unsigned Idx, Attributes Attrs) { AttributeWithIndex P; P.Index = Idx; @@ -110,16 +340,22 @@ struct AttributeWithIndex { return P; } }; - + //===----------------------------------------------------------------------===// // AttrListPtr Smart Pointer //===----------------------------------------------------------------------===// class AttributeListImpl; - -/// AttrListPtr - This class manages the ref count for the opaque + +/// AttrListPtr - This class manages the ref count for the opaque /// AttributeListImpl object and provides accessors for it. class AttrListPtr { +public: + enum AttrIndex { + ReturnIndex = 0U, + FunctionIndex = ~0U + }; +private: /// AttrList - The attributes that we are managing. This can be null /// to represent the empty attributes list. AttributeListImpl *AttrList; @@ -128,115 +364,106 @@ public: AttrListPtr(const AttrListPtr &P); const AttrListPtr &operator=(const AttrListPtr &RHS); ~AttrListPtr(); - + //===--------------------------------------------------------------------===// // Attribute List Construction and Mutation //===--------------------------------------------------------------------===// - - /// get - Return a Attributes list with the specified parameter in it. - static AttrListPtr get(const AttributeWithIndex *Attr, unsigned NumAttrs); - - /// get - Return a Attribute list with the parameters specified by the - /// consecutive random access iterator range. - template - static AttrListPtr get(const Iter &I, const Iter &E) { - if (I == E) return AttrListPtr(); // Empty list. - return get(&*I, static_cast(E-I)); - } + + /// get - Return a Attributes list with the specified parameters in it. + static AttrListPtr get(ArrayRef Attrs); /// addAttr - Add the specified attribute at the specified index to this /// attribute list. Since attribute lists are immutable, this /// returns the new list. - AttrListPtr addAttr(unsigned Idx, Attributes Attrs) const; - + AttrListPtr addAttr(LLVMContext &C, unsigned Idx, Attributes Attrs) const; + /// removeAttr - Remove the specified attribute at the specified index from /// this attribute list. Since attribute lists are immutable, this /// returns the new list. - AttrListPtr removeAttr(unsigned Idx, Attributes Attrs) const; - + AttrListPtr removeAttr(LLVMContext &C, unsigned Idx, Attributes Attrs) const; + //===--------------------------------------------------------------------===// // Attribute List Accessors //===--------------------------------------------------------------------===// /// getParamAttributes - The attributes for the specified index are - /// returned. + /// returned. Attributes getParamAttributes(unsigned Idx) const { - assert (Idx && Idx != ~0U && "Invalid parameter index!"); return getAttributes(Idx); } /// getRetAttributes - The attributes for the ret value are - /// returned. + /// returned. Attributes getRetAttributes() const { - return getAttributes(0); + return getAttributes(ReturnIndex); } /// getFnAttributes - The function attributes are returned. Attributes getFnAttributes() const { - return getAttributes(~0); + return getAttributes(FunctionIndex); } - + /// paramHasAttr - Return true if the specified parameter index has the /// specified attribute set. bool paramHasAttr(unsigned Idx, Attributes Attr) const { - return getAttributes(Idx) & Attr; + return getAttributes(Idx).hasAttributes(Attr); } - + /// getParamAlignment - Return the alignment for the specified function /// parameter. unsigned getParamAlignment(unsigned Idx) const { - Attributes Align = getAttributes(Idx) & Attribute::Alignment; - if (Align == 0) - return 0; - - return 1ull << ((Align >> 16) - 1); + return getAttributes(Idx).getAlignment(); } - + /// hasAttrSomewhere - Return true if the specified attribute is set for at /// least one parameter or for the return value. - bool hasAttrSomewhere(Attributes Attr) const; + bool hasAttrSomewhere(Attributes::AttrVal Attr) const; + + unsigned getNumAttrs() const; + Attributes &getAttributesAtIndex(unsigned i) const; /// operator==/!= - Provide equality predicates. - bool operator==(const AttrListPtr &RHS) const { return AttrList == RHS.AttrList; } - bool operator!=(const AttrListPtr &RHS) const { return AttrList != RHS.AttrList; } - + bool operator==(const AttrListPtr &RHS) const + { return AttrList == RHS.AttrList; } + bool operator!=(const AttrListPtr &RHS) const + { return AttrList != RHS.AttrList; } + void dump() const; //===--------------------------------------------------------------------===// // Attribute List Introspection //===--------------------------------------------------------------------===// - + /// getRawPointer - Return a raw pointer that uniquely identifies this - /// attribute list. + /// attribute list. void *getRawPointer() const { return AttrList; } - + // Attributes are stored as a dense set of slots, where there is one // slot for each argument that has an attribute. This allows walking over the // dense set instead of walking the sparse list of attributes. - + /// isEmpty - Return true if there are no attributes. /// bool isEmpty() const { return AttrList == 0; } - - /// getNumSlots - Return the number of slots used in this attribute list. + + /// getNumSlots - Return the number of slots used in this attribute list. /// This is the number of arguments that have an attribute set on them /// (including the function itself). unsigned getNumSlots() const; - + /// getSlot - Return the AttributeWithIndex at the specified slot. This /// holds a index number plus a set of attributes. const AttributeWithIndex &getSlot(unsigned Slot) const; - + private: explicit AttrListPtr(AttributeListImpl *L); /// getAttributes - The attributes for the specified index are /// returned. Attributes for the result are denoted with Idx = 0. Attributes getAttributes(unsigned Idx) const; - }; } // End llvm namespace