From 55fb5bcc62804f7696b98f9f8d987da515dac66a Mon Sep 17 00:00:00 2001 From: Kostya Serebryany Date: Wed, 8 Feb 2012 01:11:21 +0000 Subject: [PATCH] Don't use static CTORs for the Attributes constants, while still keeping the class type-safe git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@150031 91177308-0d34-0410-b5e6-96231b3b80d8 --- include/llvm/Attributes.h | 126 +++++++++++++++++++++++--------------- 1 file changed, 78 insertions(+), 48 deletions(-) diff --git a/include/llvm/Attributes.h b/include/llvm/Attributes.h index 6082cf05c81..0099f173b62 100644 --- a/include/llvm/Attributes.h +++ b/include/llvm/Attributes.h @@ -22,11 +22,29 @@ 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. class Attributes { public: Attributes() : Bits(0) { } explicit Attributes(uint64_t Val) : Bits(Val) { } + /*implicit*/ Attributes(Attribute::AttrConst Val) : Bits(Val.v) { } Attributes(const Attributes &Attrs) : Bits(Attrs.Bits) { } // This is a "safe bool() operator". operator const void *() const { return Bits ? this : 0; } @@ -73,45 +91,55 @@ namespace Attribute { /// 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) +// 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 -const Attributes NoCapture (1<<21); ///< Function creates no aliases of pointer -const Attributes NoRedZone (1<<22); /// disable redzone -const Attributes NoImplicitFloat (1<<23); /// disable implicit floating point - /// instructions. -const Attributes Naked (1<<24); ///< Naked function -const Attributes InlineHint (1<<25); ///< source said inlining was - ///desirable -const Attributes 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)) -const Attributes ReturnsTwice (1<<29); ///< Function can return twice -const Attributes UWTable (1<<30); ///< Function must be in a unwind - ///table -const Attributes NonLazyBind (1U<<31); ///< Function is called early and/or - /// often, so lazy binding isn't - /// worthwhile. -const Attributes AddressSafety(1ULL<<32); ///< Address safety checking is on. +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 @@ -126,24 +154,26 @@ const Attributes AddressSafety(1ULL<<32); ///< Address safety checking is on. /// uwtable + nounwind = Needs an entry because the ABI says so. /// @brief Attributes that only apply to function parameters. -const Attributes ParameterOnly = ByVal | Nest | StructRet | NoCapture; +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 Attributes FunctionOnly = NoReturn | NoUnwind | ReadNone | ReadOnly | - NoInline | AlwaysInline | OptimizeForSize | StackProtect | StackProtectReq | - NoRedZone | NoImplicitFloat | Naked | InlineHint | StackAlignment | - UWTable | NonLazyBind | ReturnsTwice | AddressSafety; +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[4] = { + {ByVal_i | InReg_i | Nest_i | StructRet_i}, + {ZExt_i | SExt_i}, + {ReadNone_i | ReadOnly_i}, + {NoInline_i | AlwaysInline_i} }; /// @brief Which attributes cannot be applied to a type. -- 2.34.1