+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.
+
+} // namespace Attribute
+
+/// AttributeImpl - The internal representation of the Attributes class. This is
+/// uniquified.
+class AttributesImpl;
+
+/// Attributes - A bitset of attributes.
+class Attributes {
+public:
+ enum AttrVal {
+ 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;
+
+ explicit Attributes(AttributesImpl *A);
+public:
+ Attributes() : Attrs(0) {}
+ explicit Attributes(uint64_t Val);
+ /*implicit*/ Attributes(Attribute::AttrConst Val);
+ Attributes(const Attributes &A);
+
+ class Builder {
+ friend class Attributes;
+ uint64_t Bits;
+ public:
+ Builder() : Bits(0) {}
+ Builder(const Attributes &A) : Bits(A.Raw()) {}
+
+ void clear() { Bits = 0; }
+
+ bool hasAttributes() const;
+ bool hasAttributes(const Attributes &A) const;
+ bool hasAlignmentAttr() const;
+
+ uint64_t getAlignment() const;
+
+ Builder &addAttribute(Attributes::AttrVal Val);
+ Builder &removeAttribute(Attributes::AttrVal Val);
+
+ void addAlignmentAttr(unsigned Align);
+ void addStackAlignmentAttr(unsigned Align);
+
+ void removeAttributes(const Attributes &A);
+
+ /// @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);
+ }
+ };
+
+ /// get - Return a uniquified Attributes object. This takes the uniquified
+ /// value from the Builder and wraps it in the Attributes class.
+ static Attributes get(Builder &B);
+ static Attributes get(LLVMContext &Context, Builder &B);
+
+ /// @brief Return true if the attribute is present.
+ bool hasAttribute(AttrVal Val) const;
+
+ /// @brief Return true if attributes exist
+ bool hasAttributes() const {
+ return Attrs.hasAttributes();
+ }
+
+ /// @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 isEmptyOrSingleton() const;
+
+ // This is a "safe bool() operator".
+ operator const void *() const { return Attrs.Bits ? this : 0; }
+ bool operator == (const Attributes &A) const {
+ return Attrs.Bits == A.Attrs.Bits;
+ }
+ bool operator != (const Attributes &A) const {
+ return Attrs.Bits != A.Attrs.Bits;
+ }
+
+ Attributes operator | (const Attributes &A) const;
+ Attributes operator & (const Attributes &A) const;
+ Attributes operator ^ (const Attributes &A) const;
+ Attributes &operator |= (const Attributes &A);
+ Attributes &operator &= (const Attributes &A);
+ Attributes operator ~ () const;
+
+ uint64_t Raw() const;
+
+ /// constructAlignmentFromInt - This turns an int alignment (a power of 2,
+ /// normally) into the form used internally in Attributes.
+ static Attributes constructAlignmentFromInt(unsigned i) {
+ // Default alignment, allow the target to define how to align it.
+ if (i == 0)
+ return Attributes();
+
+ assert(isPowerOf2_32(i) && "Alignment must be a power of two.");
+ assert(i <= 0x40000000 && "Alignment too large.");
+ return Attributes((Log2_32(i)+1) << 16);
+ }
+
+ /// constructStackAlignmentFromInt - This turns an int stack alignment (which
+ /// must be a power of 2) into the form used internally in Attributes.
+ static Attributes constructStackAlignmentFromInt(unsigned i) {
+ // Default alignment, allow the target to define how to align it.
+ if (i == 0)
+ return Attributes();
+
+ assert(isPowerOf2_32(i) && "Alignment must be a power of two.");
+ assert(i <= 0x100 && "Alignment too large.");
+ return Attributes((Log2_32(i)+1) << 26);
+ }
+
+ /// @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(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 |= Attributes::constructAlignmentFromInt(Alignment);
+ Attrs |= Attributes((EncodedAttrs & (0xfffULL << 32)) >> 11);
+ return Attrs;
+ }
+
+ /// 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;