X-Git-Url: http://plrg.eecs.uci.edu/git/?a=blobdiff_plain;f=include%2Fllvm%2FAttributes.h;h=0228d8691d2d9f46b30a501a947d15fa331229e2;hb=4e2132e7ae4b41ff6093bbaebcb852105277ac53;hp=50a4cef9ea91d752bf2fba9f8d159bd70fa918f5;hpb=6d1b8a5911b98b49c3a17874f8a9cc3dfa9fa6f0;p=oota-llvm.git diff --git a/include/llvm/Attributes.h b/include/llvm/Attributes.h index 50a4cef9ea9..0228d8691d2 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 // @@ -15,85 +15,270 @@ #ifndef LLVM_ATTRIBUTES_H #define LLVM_ATTRIBUTES_H +#include "llvm/Support/MathExtras.h" +#include "llvm/ADT/ArrayRef.h" #include #include namespace llvm { class Type; +namespace Attribute { +/// We use this proxy POD type to allow constructing Attributes constants +/// using initializer lists. Do not use this class directly. +struct AttrConst { + uint64_t v; + AttrConst operator | (const AttrConst Attrs) const { + AttrConst Res = {v | Attrs.v}; + return Res; + } + AttrConst operator ~ () const { + AttrConst Res = {~v}; + return Res; + } +}; +} // namespace Attribute + + /// Attributes - A bitset of attributes. -typedef unsigned Attributes; - +class Attributes { + public: + Attributes() : Bits(0) { } + explicit Attributes(uint64_t Val) : Bits(Val) { } + /*implicit*/ Attributes(Attribute::AttrConst Val) : Bits(Val.v) { } + // This is a "safe bool() operator". + operator const void *() const { return Bits ? this : 0; } + bool isEmptyOrSingleton() const { return (Bits & (Bits - 1)) == 0; } + bool operator == (const Attributes &Attrs) const { + return Bits == Attrs.Bits; + } + bool operator != (const Attributes &Attrs) const { + return Bits != Attrs.Bits; + } + Attributes operator | (const Attributes &Attrs) const { + return Attributes(Bits | Attrs.Bits); + } + Attributes operator & (const Attributes &Attrs) const { + return Attributes(Bits & Attrs.Bits); + } + Attributes operator ^ (const Attributes &Attrs) const { + return Attributes(Bits ^ Attrs.Bits); + } + Attributes &operator |= (const Attributes &Attrs) { + Bits |= Attrs.Bits; + return *this; + } + Attributes &operator &= (const Attributes &Attrs) { + Bits &= Attrs.Bits; + return *this; + } + Attributes operator ~ () const { return Attributes(~Bits); } + uint64_t Raw() const { return Bits; } + private: + // Currently, we need less than 64 bits. + uint64_t Bits; +}; + 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 +/// 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 Alignment = 0xffff<<16; ///< Alignment of parameter (16 bits) - // 0 = unknown, else in clear (not log) - +// We declare AttrConst objects that will be used throughout the code +// and also raw uint64_t objects with _i suffix to be used below for other +// constant declarations. This is done to avoid static CTORs and at the same +// time to keep type-safety of Attributes. +#define DECLARE_LLVM_ATTRIBUTE(name, value) \ + const uint64_t name##_i = value; \ + const AttrConst name = {value}; + +DECLARE_LLVM_ATTRIBUTE(None,0) ///< No attributes have been set +DECLARE_LLVM_ATTRIBUTE(ZExt,1<<0) ///< Zero extended before/after call +DECLARE_LLVM_ATTRIBUTE(SExt,1<<1) ///< Sign extended before/after call +DECLARE_LLVM_ATTRIBUTE(NoReturn,1<<2) ///< Mark the function as not returning +DECLARE_LLVM_ATTRIBUTE(InReg,1<<3) ///< Force argument to be passed in register +DECLARE_LLVM_ATTRIBUTE(StructRet,1<<4) ///< Hidden pointer to structure to return +DECLARE_LLVM_ATTRIBUTE(NoUnwind,1<<5) ///< Function doesn't unwind stack +DECLARE_LLVM_ATTRIBUTE(NoAlias,1<<6) ///< Considered to not alias after call +DECLARE_LLVM_ATTRIBUTE(ByVal,1<<7) ///< Pass structure by value +DECLARE_LLVM_ATTRIBUTE(Nest,1<<8) ///< Nested function static chain +DECLARE_LLVM_ATTRIBUTE(ReadNone,1<<9) ///< Function does not access memory +DECLARE_LLVM_ATTRIBUTE(ReadOnly,1<<10) ///< Function only reads from memory +DECLARE_LLVM_ATTRIBUTE(NoInline,1<<11) ///< inline=never +DECLARE_LLVM_ATTRIBUTE(AlwaysInline,1<<12) ///< inline=always +DECLARE_LLVM_ATTRIBUTE(OptimizeForSize,1<<13) ///< opt_size +DECLARE_LLVM_ATTRIBUTE(StackProtect,1<<14) ///< Stack protection. +DECLARE_LLVM_ATTRIBUTE(StackProtectReq,1<<15) ///< Stack protection required. +DECLARE_LLVM_ATTRIBUTE(Alignment,31<<16) ///< Alignment of parameter (5 bits) + // stored as log2 of alignment with +1 bias + // 0 means unaligned different from align 1 +DECLARE_LLVM_ATTRIBUTE(NoCapture,1<<21) ///< Function creates no aliases of pointer +DECLARE_LLVM_ATTRIBUTE(NoRedZone,1<<22) /// disable redzone +DECLARE_LLVM_ATTRIBUTE(NoImplicitFloat,1<<23) /// disable implicit floating point + /// instructions. +DECLARE_LLVM_ATTRIBUTE(Naked,1<<24) ///< Naked function +DECLARE_LLVM_ATTRIBUTE(InlineHint,1<<25) ///< source said inlining was + ///desirable +DECLARE_LLVM_ATTRIBUTE(StackAlignment,7<<26) ///< Alignment of stack for + ///function (3 bits) stored as log2 + ///of alignment with +1 bias + ///0 means unaligned (different from + ///alignstack= {1)) +DECLARE_LLVM_ATTRIBUTE(ReturnsTwice,1<<29) ///< Function can return twice +DECLARE_LLVM_ATTRIBUTE(UWTable,1<<30) ///< Function must be in a unwind + ///table +DECLARE_LLVM_ATTRIBUTE(NonLazyBind,1U<<31) ///< Function is called early and/or + /// often, so lazy binding isn't + /// worthwhile. +DECLARE_LLVM_ATTRIBUTE(AddressSafety,1ULL<<32) ///< Address safety checking is on. + +#undef DECLARE_LLVM_ATTRIBUTE + +/// 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. + /// @brief Attributes that only apply to function parameters. -const Attributes ParameterOnly = ByVal | Nest | StructRet; +const AttrConst ParameterOnly = {ByVal_i | Nest_i | + StructRet_i | NoCapture_i}; -/// @brief Attributes that only apply to function. -const Attributes FunctionOnly = NoReturn | NoUnwind | ReadNone | ReadOnly; +/// @brief Attributes that may be applied to the function itself. These cannot +/// be used on return values or function parameters. +const AttrConst FunctionOnly = {NoReturn_i | NoUnwind_i | ReadNone_i | + ReadOnly_i | NoInline_i | AlwaysInline_i | OptimizeForSize_i | + StackProtect_i | StackProtectReq_i | NoRedZone_i | NoImplicitFloat_i | + Naked_i | InlineHint_i | StackAlignment_i | + UWTable_i | NonLazyBind_i | ReturnsTwice_i | AddressSafety_i}; /// @brief Parameter attributes that do not apply to vararg call arguments. -const Attributes VarArgsIncompatible = StructRet; +const AttrConst VarArgsIncompatible = {StructRet_i}; /// @brief Attributes that are mutually incompatible. -const Attributes MutuallyIncompatible[4] = { - ByVal | InReg | Nest | StructRet, - ZExt | SExt, - ReadNone | ReadOnly, - NoInline | AlwaysInline +const AttrConst MutuallyIncompatible[5] = { + {ByVal_i | Nest_i | StructRet_i}, + {ByVal_i | Nest_i | InReg_i }, + {ZExt_i | SExt_i}, + {ReadNone_i | ReadOnly_i}, + {NoInline_i | AlwaysInline_i} }; /// @brief Which attributes cannot be applied to a type. -Attributes typeIncompatible(const Type *Ty); +Attributes typeIncompatible(Type *Ty); /// This turns an int alignment (a power of 2, normally) into the /// form used internally in Attributes. inline Attributes constructAlignmentFromInt(unsigned i) { - return (i << 16); + // Default alignment, allow the target to define how to align it. + if (i == 0) + return None; + + assert(isPowerOf2_32(i) && "Alignment must be a power of two."); + assert(i <= 0x40000000 && "Alignment too large."); + return Attributes((Log2_32(i)+1) << 16); } +/// This returns the alignment field of an attribute as a byte alignment value. +inline unsigned getAlignmentFromAttrs(Attributes A) { + Attributes Align = A & Attribute::Alignment; + if (!Align) + return 0; + + return 1U << ((Align.Raw() >> 16) - 1); +} + +/// This turns an int stack alignment (which must be a power of 2) into +/// the form used internally in Attributes. +inline Attributes constructStackAlignmentFromInt(unsigned i) { + // Default alignment, allow the target to define how to align it. + if (i == 0) + return None; + + assert(isPowerOf2_32(i) && "Alignment must be a power of two."); + assert(i <= 0x100 && "Alignment too large."); + return Attributes((Log2_32(i)+1) << 26); +} + +/// This returns the stack alignment field of an attribute as a byte alignment +/// value. +inline unsigned getStackAlignmentFromAttrs(Attributes A) { + Attributes StackAlign = A & Attribute::StackAlignment; + if (!StackAlign) + return 0; + + return 1U << ((StackAlign.Raw() >> 26) - 1); +} + +/// 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. +inline 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 & Attribute::Alignment) + EncodedAttrs |= (1ull << 16) << + (((Attrs & Attribute::Alignment).Raw()-1) >> 16); + EncodedAttrs |= (Attrs.Raw() & (0xfffull << 21)) << 11; + + return EncodedAttrs; +} + +/// 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'. +inline Attributes decodeLLVMAttributesForBitcode(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 Attrs(EncodedAttrs & 0xffff); + if (Alignment) + Attrs |= Attribute::constructAlignmentFromInt(Alignment); + Attrs |= Attributes((EncodedAttrs & (0xfffull << 32)) >> 11); + + return Attrs; +} + + /// 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. +/// the mnemonics for the assembly writer. /// @brief Convert attribute bits to text std::string getAsString(Attributes Attrs); } // end namespace Attribute -namespace Attribute { -} // end namespace Attribute - /// This is just a pair of values to associate a set of attributes -/// with an index. +/// 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. - + static AttributeWithIndex get(unsigned Idx, Attributes Attrs) { AttributeWithIndex P; P.Index = Idx; @@ -101,14 +286,14 @@ 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 { /// AttrList - The attributes that we are managing. This can be null @@ -119,104 +304,98 @@ 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; - + /// 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; - + //===--------------------------------------------------------------------===// // 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); } - /// getFnAttributes - The function attributes are returned. + /// getFnAttributes - The function attributes are returned. Attributes getFnAttributes() const { - return getAttributes(~0); + return getAttributes(~0U); } - + /// paramHasAttr - Return true if the specified parameter index has the /// specified attribute set. bool paramHasAttr(unsigned Idx, Attributes Attr) const { return getAttributes(Idx) & Attr; } - + /// getParamAlignment - Return the alignment for the specified function /// parameter. unsigned getParamAlignment(unsigned Idx) const { - return (getAttributes(Idx) & Attribute::Alignment) >> 16; + return Attribute::getAlignmentFromAttrs(getAttributes(Idx)); } - + /// hasAttrSomewhere - Return true if the specified attribute is set for at /// least one parameter or for the return value. bool hasAttrSomewhere(Attributes Attr) 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);