diff options
| -rw-r--r-- | include/llvm/Attributes.h | 163 | ||||
| -rw-r--r-- | lib/Bitcode/Reader/BitcodeReader.cpp | 2 | ||||
| -rw-r--r-- | lib/Bitcode/Writer/BitcodeWriter.cpp | 2 |
3 files changed, 80 insertions, 87 deletions
diff --git a/include/llvm/Attributes.h b/include/llvm/Attributes.h index 493af92a56..3a204b949e 100644 --- a/include/llvm/Attributes.h +++ b/include/llvm/Attributes.h @@ -96,6 +96,42 @@ DECLARE_LLVM_ATTRIBUTE(AddressSafety,1ULL<<32) ///< Address safety checking is o #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 AttrConst ParameterOnly = {ByVal_i | Nest_i | + StructRet_i | NoCapture_i}; + +/// @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 AttrConst VarArgsIncompatible = {StructRet_i}; + +/// @brief Attributes that are mutually incompatible. +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} +}; + } // namespace Attribute /// Attributes - A bitset of attributes. @@ -276,100 +312,57 @@ public: Attributes operator ~ () const { return Attributes(~Bits); } uint64_t Raw() const { return Bits; } - /// @brief Which attributes cannot be applied to a type. - static Attributes typeIncompatible(Type *Ty); - /// 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; -}; -namespace 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 AttrConst ParameterOnly = {ByVal_i | Nest_i | - StructRet_i | NoCapture_i}; - -/// @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 AttrConst VarArgsIncompatible = {StructRet_i}; + /// @brief Which attributes cannot be applied to a type. + static Attributes typeIncompatible(Type *Ty); -/// @brief Attributes that are mutually incompatible. -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} + /// 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.hasAlignmentAttr()) + EncodedAttrs |= (1ull << 16) << + ((Attrs.getRawAlignment() - 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'. + 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; + } }; -/// 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.hasAlignmentAttr()) - EncodedAttrs |= (1ull << 16) << - ((Attrs.getRawAlignment() - 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 |= Attributes::constructAlignmentFromInt(Alignment); - Attrs |= Attributes((EncodedAttrs & (0xfffull << 32)) >> 11); - - return Attrs; -} - -} // end namespace Attribute - /// This is just a pair of values to associate a set of attributes /// with an index. struct AttributeWithIndex { diff --git a/lib/Bitcode/Reader/BitcodeReader.cpp b/lib/Bitcode/Reader/BitcodeReader.cpp index 2b2c36ba0f..b69a362896 100644 --- a/lib/Bitcode/Reader/BitcodeReader.cpp +++ b/lib/Bitcode/Reader/BitcodeReader.cpp @@ -477,7 +477,7 @@ bool BitcodeReader::ParseAttributeBlock() { for (unsigned i = 0, e = Record.size(); i != e; i += 2) { Attributes ReconstitutedAttr = - Attribute::decodeLLVMAttributesForBitcode(Record[i+1]); + Attributes::decodeLLVMAttributesForBitcode(Record[i+1]); Record[i+1] = ReconstitutedAttr.Raw(); } diff --git a/lib/Bitcode/Writer/BitcodeWriter.cpp b/lib/Bitcode/Writer/BitcodeWriter.cpp index 94ebe190d4..b3f1bb13a9 100644 --- a/lib/Bitcode/Writer/BitcodeWriter.cpp +++ b/lib/Bitcode/Writer/BitcodeWriter.cpp @@ -177,7 +177,7 @@ static void WriteAttributeTable(const ValueEnumerator &VE, for (unsigned i = 0, e = A.getNumSlots(); i != e; ++i) { const AttributeWithIndex &PAWI = A.getSlot(i); Record.push_back(PAWI.Index); - Record.push_back(Attribute::encodeLLVMAttributesForBitcode(PAWI.Attrs)); + Record.push_back(Attributes::encodeLLVMAttributesForBitcode(PAWI.Attrs)); } Stream.EmitRecord(bitc::PARAMATTR_CODE_ENTRY, Record); |