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|
{-# LANGUAGE CPP, GeneralizedNewtypeDeriving #-}
--------------------------------------------------------------------------------
-- | The LLVM Type System.
--
module GHC.Llvm.Types where
#include "HsVersions.h"
import GhcPrelude
import Data.Char
import Data.Int
import Numeric
import GHC.Driver.Session
import FastString
import Outputable
import Unique
-- from NCG
import GHC.CmmToAsm.Ppr
import GHC.Float
-- -----------------------------------------------------------------------------
-- * LLVM Basic Types and Variables
--
-- | A global mutable variable. Maybe defined or external
data LMGlobal = LMGlobal {
getGlobalVar :: LlvmVar, -- ^ Returns the variable of the 'LMGlobal'
getGlobalValue :: Maybe LlvmStatic -- ^ Return the value of the 'LMGlobal'
}
-- | A String in LLVM
type LMString = FastString
-- | A type alias
type LlvmAlias = (LMString, LlvmType)
-- | Llvm Types
data LlvmType
= LMInt Int -- ^ An integer with a given width in bits.
| LMFloat -- ^ 32 bit floating point
| LMDouble -- ^ 64 bit floating point
| LMFloat80 -- ^ 80 bit (x86 only) floating point
| LMFloat128 -- ^ 128 bit floating point
| LMPointer LlvmType -- ^ A pointer to a 'LlvmType'
| LMArray Int LlvmType -- ^ An array of 'LlvmType'
| LMVector Int LlvmType -- ^ A vector of 'LlvmType'
| LMLabel -- ^ A 'LlvmVar' can represent a label (address)
| LMVoid -- ^ Void type
| LMStruct [LlvmType] -- ^ Packed structure type
| LMStructU [LlvmType] -- ^ Unpacked structure type
| LMAlias LlvmAlias -- ^ A type alias
| LMMetadata -- ^ LLVM Metadata
-- | Function type, used to create pointers to functions
| LMFunction LlvmFunctionDecl
deriving (Eq)
instance Outputable LlvmType where
ppr (LMInt size ) = char 'i' <> ppr size
ppr (LMFloat ) = text "float"
ppr (LMDouble ) = text "double"
ppr (LMFloat80 ) = text "x86_fp80"
ppr (LMFloat128 ) = text "fp128"
ppr (LMPointer x ) = ppr x <> char '*'
ppr (LMArray nr tp ) = char '[' <> ppr nr <> text " x " <> ppr tp <> char ']'
ppr (LMVector nr tp ) = char '<' <> ppr nr <> text " x " <> ppr tp <> char '>'
ppr (LMLabel ) = text "label"
ppr (LMVoid ) = text "void"
ppr (LMStruct tys ) = text "<{" <> ppCommaJoin tys <> text "}>"
ppr (LMStructU tys ) = text "{" <> ppCommaJoin tys <> text "}"
ppr (LMMetadata ) = text "metadata"
ppr (LMFunction (LlvmFunctionDecl _ _ _ r varg p _))
= ppr r <+> lparen <> ppParams varg p <> rparen
ppr (LMAlias (s,_)) = char '%' <> ftext s
ppParams :: LlvmParameterListType -> [LlvmParameter] -> SDoc
ppParams varg p
= let varg' = case varg of
VarArgs | null args -> sLit "..."
| otherwise -> sLit ", ..."
_otherwise -> sLit ""
-- by default we don't print param attributes
args = map fst p
in ppCommaJoin args <> ptext varg'
-- | An LLVM section definition. If Nothing then let LLVM decide the section
type LMSection = Maybe LMString
type LMAlign = Maybe Int
data LMConst = Global -- ^ Mutable global variable
| Constant -- ^ Constant global variable
| Alias -- ^ Alias of another variable
deriving (Eq)
-- | LLVM Variables
data LlvmVar
-- | Variables with a global scope.
= LMGlobalVar LMString LlvmType LlvmLinkageType LMSection LMAlign LMConst
-- | Variables local to a function or parameters.
| LMLocalVar Unique LlvmType
-- | Named local variables. Sometimes we need to be able to explicitly name
-- variables (e.g for function arguments).
| LMNLocalVar LMString LlvmType
-- | A constant variable
| LMLitVar LlvmLit
deriving (Eq)
instance Outputable LlvmVar where
ppr (LMLitVar x) = ppr x
ppr (x ) = ppr (getVarType x) <+> ppName x
-- | Llvm Literal Data.
--
-- These can be used inline in expressions.
data LlvmLit
-- | Refers to an integer constant (i64 42).
= LMIntLit Integer LlvmType
-- | Floating point literal
| LMFloatLit Double LlvmType
-- | Literal NULL, only applicable to pointer types
| LMNullLit LlvmType
-- | Vector literal
| LMVectorLit [LlvmLit]
-- | Undefined value, random bit pattern. Useful for optimisations.
| LMUndefLit LlvmType
deriving (Eq)
instance Outputable LlvmLit where
ppr l@(LMVectorLit {}) = ppLit l
ppr l = ppr (getLitType l) <+> ppLit l
-- | Llvm Static Data.
--
-- These represent the possible global level variables and constants.
data LlvmStatic
= LMComment LMString -- ^ A comment in a static section
| LMStaticLit LlvmLit -- ^ A static variant of a literal value
| LMUninitType LlvmType -- ^ For uninitialised data
| LMStaticStr LMString LlvmType -- ^ Defines a static 'LMString'
| LMStaticArray [LlvmStatic] LlvmType -- ^ A static array
| LMStaticStruc [LlvmStatic] LlvmType -- ^ A static structure type
| LMStaticPointer LlvmVar -- ^ A pointer to other data
-- static expressions, could split out but leave
-- for moment for ease of use. Not many of them.
| LMTrunc LlvmStatic LlvmType -- ^ Truncate
| LMBitc LlvmStatic LlvmType -- ^ Pointer to Pointer conversion
| LMPtoI LlvmStatic LlvmType -- ^ Pointer to Integer conversion
| LMAdd LlvmStatic LlvmStatic -- ^ Constant addition operation
| LMSub LlvmStatic LlvmStatic -- ^ Constant subtraction operation
instance Outputable LlvmStatic where
ppr (LMComment s) = text "; " <> ftext s
ppr (LMStaticLit l ) = ppr l
ppr (LMUninitType t) = ppr t <> text " undef"
ppr (LMStaticStr s t) = ppr t <> text " c\"" <> ftext s <> text "\\00\""
ppr (LMStaticArray d t) = ppr t <> text " [" <> ppCommaJoin d <> char ']'
ppr (LMStaticStruc d t) = ppr t <> text "<{" <> ppCommaJoin d <> text "}>"
ppr (LMStaticPointer v) = ppr v
ppr (LMTrunc v t)
= ppr t <> text " trunc (" <> ppr v <> text " to " <> ppr t <> char ')'
ppr (LMBitc v t)
= ppr t <> text " bitcast (" <> ppr v <> text " to " <> ppr t <> char ')'
ppr (LMPtoI v t)
= ppr t <> text " ptrtoint (" <> ppr v <> text " to " <> ppr t <> char ')'
ppr (LMAdd s1 s2)
= pprStaticArith s1 s2 (sLit "add") (sLit "fadd") "LMAdd"
ppr (LMSub s1 s2)
= pprStaticArith s1 s2 (sLit "sub") (sLit "fsub") "LMSub"
pprSpecialStatic :: LlvmStatic -> SDoc
pprSpecialStatic (LMBitc v t) =
ppr (pLower t) <> text ", bitcast (" <> ppr v <> text " to " <> ppr t
<> char ')'
pprSpecialStatic v@(LMStaticPointer x) = ppr (pLower $ getVarType x) <> comma <+> ppr v
pprSpecialStatic stat = ppr stat
pprStaticArith :: LlvmStatic -> LlvmStatic -> PtrString -> PtrString
-> String -> SDoc
pprStaticArith s1 s2 int_op float_op op_name =
let ty1 = getStatType s1
op = if isFloat ty1 then float_op else int_op
in if ty1 == getStatType s2
then ppr ty1 <+> ptext op <+> lparen <> ppr s1 <> comma <> ppr s2 <> rparen
else pprPanic "pprStaticArith" $
text op_name <> text " with different types! s1: " <> ppr s1
<> text", s2: " <> ppr s2
-- -----------------------------------------------------------------------------
-- ** Operations on LLVM Basic Types and Variables
--
-- | Return the variable name or value of the 'LlvmVar'
-- in Llvm IR textual representation (e.g. @\@x@, @%y@ or @42@).
ppName :: LlvmVar -> SDoc
ppName v@(LMGlobalVar {}) = char '@' <> ppPlainName v
ppName v@(LMLocalVar {}) = char '%' <> ppPlainName v
ppName v@(LMNLocalVar {}) = char '%' <> ppPlainName v
ppName v@(LMLitVar {}) = ppPlainName v
-- | Return the variable name or value of the 'LlvmVar'
-- in a plain textual representation (e.g. @x@, @y@ or @42@).
ppPlainName :: LlvmVar -> SDoc
ppPlainName (LMGlobalVar x _ _ _ _ _) = ftext x
ppPlainName (LMLocalVar x LMLabel ) = text (show x)
ppPlainName (LMLocalVar x _ ) = text ('l' : show x)
ppPlainName (LMNLocalVar x _ ) = ftext x
ppPlainName (LMLitVar x ) = ppLit x
-- | Print a literal value. No type.
ppLit :: LlvmLit -> SDoc
ppLit (LMIntLit i (LMInt 32)) = ppr (fromInteger i :: Int32)
ppLit (LMIntLit i (LMInt 64)) = ppr (fromInteger i :: Int64)
ppLit (LMIntLit i _ ) = ppr ((fromInteger i)::Int)
ppLit (LMFloatLit r LMFloat ) = ppFloat $ narrowFp r
ppLit (LMFloatLit r LMDouble) = ppDouble r
ppLit f@(LMFloatLit _ _) = pprPanic "ppLit" (text "Can't print this float literal: " <> ppr f)
ppLit (LMVectorLit ls ) = char '<' <+> ppCommaJoin ls <+> char '>'
ppLit (LMNullLit _ ) = text "null"
-- #11487 was an issue where we passed undef for some arguments
-- that were actually live. By chance the registers holding those
-- arguments usually happened to have the right values anyways, but
-- that was not guaranteed. To find such bugs reliably, we set the
-- flag below when validating, which replaces undef literals (at
-- common types) with values that are likely to cause a crash or test
-- failure.
ppLit (LMUndefLit t ) = sdocWithDynFlags f
where f dflags
| gopt Opt_LlvmFillUndefWithGarbage dflags,
Just lit <- garbageLit t = ppLit lit
| otherwise = text "undef"
garbageLit :: LlvmType -> Maybe LlvmLit
garbageLit t@(LMInt w) = Just (LMIntLit (0xbbbbbbbbbbbbbbb0 `mod` (2^w)) t)
-- Use a value that looks like an untagged pointer, so we are more
-- likely to try to enter it
garbageLit t
| isFloat t = Just (LMFloatLit 12345678.9 t)
garbageLit t@(LMPointer _) = Just (LMNullLit t)
-- Using null isn't totally ideal, since some functions may check for null.
-- But producing another value is inconvenient since it needs a cast,
-- and the knowledge for how to format casts is in PpLlvm.
garbageLit _ = Nothing
-- More cases could be added, but this should do for now.
-- | Return the 'LlvmType' of the 'LlvmVar'
getVarType :: LlvmVar -> LlvmType
getVarType (LMGlobalVar _ y _ _ _ _) = y
getVarType (LMLocalVar _ y ) = y
getVarType (LMNLocalVar _ y ) = y
getVarType (LMLitVar l ) = getLitType l
-- | Return the 'LlvmType' of a 'LlvmLit'
getLitType :: LlvmLit -> LlvmType
getLitType (LMIntLit _ t) = t
getLitType (LMFloatLit _ t) = t
getLitType (LMVectorLit []) = panic "getLitType"
getLitType (LMVectorLit ls) = LMVector (length ls) (getLitType (head ls))
getLitType (LMNullLit t) = t
getLitType (LMUndefLit t) = t
-- | Return the 'LlvmType' of the 'LlvmStatic'
getStatType :: LlvmStatic -> LlvmType
getStatType (LMStaticLit l ) = getLitType l
getStatType (LMUninitType t) = t
getStatType (LMStaticStr _ t) = t
getStatType (LMStaticArray _ t) = t
getStatType (LMStaticStruc _ t) = t
getStatType (LMStaticPointer v) = getVarType v
getStatType (LMTrunc _ t) = t
getStatType (LMBitc _ t) = t
getStatType (LMPtoI _ t) = t
getStatType (LMAdd t _) = getStatType t
getStatType (LMSub t _) = getStatType t
getStatType (LMComment _) = error "Can't call getStatType on LMComment!"
-- | Return the 'LlvmLinkageType' for a 'LlvmVar'
getLink :: LlvmVar -> LlvmLinkageType
getLink (LMGlobalVar _ _ l _ _ _) = l
getLink _ = Internal
-- | Add a pointer indirection to the supplied type. 'LMLabel' and 'LMVoid'
-- cannot be lifted.
pLift :: LlvmType -> LlvmType
pLift LMLabel = error "Labels are unliftable"
pLift LMVoid = error "Voids are unliftable"
pLift LMMetadata = error "Metadatas are unliftable"
pLift x = LMPointer x
-- | Lift a variable to 'LMPointer' type.
pVarLift :: LlvmVar -> LlvmVar
pVarLift (LMGlobalVar s t l x a c) = LMGlobalVar s (pLift t) l x a c
pVarLift (LMLocalVar s t ) = LMLocalVar s (pLift t)
pVarLift (LMNLocalVar s t ) = LMNLocalVar s (pLift t)
pVarLift (LMLitVar _ ) = error $ "Can't lower a literal type!"
-- | Remove the pointer indirection of the supplied type. Only 'LMPointer'
-- constructors can be lowered.
pLower :: LlvmType -> LlvmType
pLower (LMPointer x) = x
pLower x = pprPanic "llvmGen(pLower)"
$ ppr x <+> text " is a unlowerable type, need a pointer"
-- | Lower a variable of 'LMPointer' type.
pVarLower :: LlvmVar -> LlvmVar
pVarLower (LMGlobalVar s t l x a c) = LMGlobalVar s (pLower t) l x a c
pVarLower (LMLocalVar s t ) = LMLocalVar s (pLower t)
pVarLower (LMNLocalVar s t ) = LMNLocalVar s (pLower t)
pVarLower (LMLitVar _ ) = error $ "Can't lower a literal type!"
-- | Test if the given 'LlvmType' is an integer
isInt :: LlvmType -> Bool
isInt (LMInt _) = True
isInt _ = False
-- | Test if the given 'LlvmType' is a floating point type
isFloat :: LlvmType -> Bool
isFloat LMFloat = True
isFloat LMDouble = True
isFloat LMFloat80 = True
isFloat LMFloat128 = True
isFloat _ = False
-- | Test if the given 'LlvmType' is an 'LMPointer' construct
isPointer :: LlvmType -> Bool
isPointer (LMPointer _) = True
isPointer _ = False
-- | Test if the given 'LlvmType' is an 'LMVector' construct
isVector :: LlvmType -> Bool
isVector (LMVector {}) = True
isVector _ = False
-- | Test if a 'LlvmVar' is global.
isGlobal :: LlvmVar -> Bool
isGlobal (LMGlobalVar _ _ _ _ _ _) = True
isGlobal _ = False
-- | Width in bits of an 'LlvmType', returns 0 if not applicable
llvmWidthInBits :: DynFlags -> LlvmType -> Int
llvmWidthInBits _ (LMInt n) = n
llvmWidthInBits _ (LMFloat) = 32
llvmWidthInBits _ (LMDouble) = 64
llvmWidthInBits _ (LMFloat80) = 80
llvmWidthInBits _ (LMFloat128) = 128
-- Could return either a pointer width here or the width of what
-- it points to. We will go with the former for now.
-- PMW: At least judging by the way LLVM outputs constants, pointers
-- should use the former, but arrays the latter.
llvmWidthInBits dflags (LMPointer _) = llvmWidthInBits dflags (llvmWord dflags)
llvmWidthInBits dflags (LMArray n t) = n * llvmWidthInBits dflags t
llvmWidthInBits dflags (LMVector n ty) = n * llvmWidthInBits dflags ty
llvmWidthInBits _ LMLabel = 0
llvmWidthInBits _ LMVoid = 0
llvmWidthInBits dflags (LMStruct tys) = sum $ map (llvmWidthInBits dflags) tys
llvmWidthInBits _ (LMStructU _) =
-- It's not trivial to calculate the bit width of the unpacked structs,
-- since they will be aligned depending on the specified datalayout (
-- http://llvm.org/docs/LangRef.html#data-layout ). One way we could support
-- this could be to make the GHC.CmmToLlvm.Ppr.moduleLayout be a data type
-- that exposes the alignment information. However, currently the only place
-- we use unpacked structs is LLVM intrinsics that return them (e.g.,
-- llvm.sadd.with.overflow.*), so we don't actually need to compute their
-- bit width.
panic "llvmWidthInBits: not implemented for LMStructU"
llvmWidthInBits _ (LMFunction _) = 0
llvmWidthInBits dflags (LMAlias (_,t)) = llvmWidthInBits dflags t
llvmWidthInBits _ LMMetadata = panic "llvmWidthInBits: Meta-data has no runtime representation!"
-- -----------------------------------------------------------------------------
-- ** Shortcut for Common Types
--
i128, i64, i32, i16, i8, i1, i8Ptr :: LlvmType
i128 = LMInt 128
i64 = LMInt 64
i32 = LMInt 32
i16 = LMInt 16
i8 = LMInt 8
i1 = LMInt 1
i8Ptr = pLift i8
-- | The target architectures word size
llvmWord, llvmWordPtr :: DynFlags -> LlvmType
llvmWord dflags = LMInt (wORD_SIZE dflags * 8)
llvmWordPtr dflags = pLift (llvmWord dflags)
-- -----------------------------------------------------------------------------
-- * LLVM Function Types
--
-- | An LLVM Function
data LlvmFunctionDecl = LlvmFunctionDecl {
-- | Unique identifier of the function
decName :: LMString,
-- | LinkageType of the function
funcLinkage :: LlvmLinkageType,
-- | The calling convention of the function
funcCc :: LlvmCallConvention,
-- | Type of the returned value
decReturnType :: LlvmType,
-- | Indicates if this function uses varargs
decVarargs :: LlvmParameterListType,
-- | Parameter types and attributes
decParams :: [LlvmParameter],
-- | Function align value, must be power of 2
funcAlign :: LMAlign
}
deriving (Eq)
instance Outputable LlvmFunctionDecl where
ppr (LlvmFunctionDecl n l c r varg p a)
= let align = case a of
Just a' -> text " align " <> ppr a'
Nothing -> empty
in ppr l <+> ppr c <+> ppr r <+> char '@' <> ftext n <>
lparen <> ppParams varg p <> rparen <> align
type LlvmFunctionDecls = [LlvmFunctionDecl]
type LlvmParameter = (LlvmType, [LlvmParamAttr])
-- | LLVM Parameter Attributes.
--
-- Parameter attributes are used to communicate additional information about
-- the result or parameters of a function
data LlvmParamAttr
-- | This indicates to the code generator that the parameter or return value
-- should be zero-extended to a 32-bit value by the caller (for a parameter)
-- or the callee (for a return value).
= ZeroExt
-- | This indicates to the code generator that the parameter or return value
-- should be sign-extended to a 32-bit value by the caller (for a parameter)
-- or the callee (for a return value).
| SignExt
-- | This indicates that this parameter or return value should be treated in
-- a special target-dependent fashion during while emitting code for a
-- function call or return (usually, by putting it in a register as opposed
-- to memory).
| InReg
-- | This indicates that the pointer parameter should really be passed by
-- value to the function.
| ByVal
-- | This indicates that the pointer parameter specifies the address of a
-- structure that is the return value of the function in the source program.
| SRet
-- | This indicates that the pointer does not alias any global or any other
-- parameter.
| NoAlias
-- | This indicates that the callee does not make any copies of the pointer
-- that outlive the callee itself
| NoCapture
-- | This indicates that the pointer parameter can be excised using the
-- trampoline intrinsics.
| Nest
deriving (Eq)
instance Outputable LlvmParamAttr where
ppr ZeroExt = text "zeroext"
ppr SignExt = text "signext"
ppr InReg = text "inreg"
ppr ByVal = text "byval"
ppr SRet = text "sret"
ppr NoAlias = text "noalias"
ppr NoCapture = text "nocapture"
ppr Nest = text "nest"
-- | Llvm Function Attributes.
--
-- Function attributes are set to communicate additional information about a
-- function. Function attributes are considered to be part of the function,
-- not of the function type, so functions with different parameter attributes
-- can have the same function type. Functions can have multiple attributes.
--
-- Descriptions taken from <http://llvm.org/docs/LangRef.html#fnattrs>
data LlvmFuncAttr
-- | This attribute indicates that the inliner should attempt to inline this
-- function into callers whenever possible, ignoring any active inlining
-- size threshold for this caller.
= AlwaysInline
-- | This attribute indicates that the source code contained a hint that
-- inlining this function is desirable (such as the \"inline\" keyword in
-- C/C++). It is just a hint; it imposes no requirements on the inliner.
| InlineHint
-- | This attribute indicates that the inliner should never inline this
-- function in any situation. This attribute may not be used together
-- with the alwaysinline attribute.
| NoInline
-- | This attribute suggests that optimization passes and code generator
-- passes make choices that keep the code size of this function low, and
-- otherwise do optimizations specifically to reduce code size.
| OptSize
-- | This function attribute indicates that the function never returns
-- normally. This produces undefined behavior at runtime if the function
-- ever does dynamically return.
| NoReturn
-- | This function attribute indicates that the function never returns with
-- an unwind or exceptional control flow. If the function does unwind, its
-- runtime behavior is undefined.
| NoUnwind
-- | This attribute indicates that the function computes its result (or
-- decides to unwind an exception) based strictly on its arguments, without
-- dereferencing any pointer arguments or otherwise accessing any mutable
-- state (e.g. memory, control registers, etc) visible to caller functions.
-- It does not write through any pointer arguments (including byval
-- arguments) and never changes any state visible to callers. This means
-- that it cannot unwind exceptions by calling the C++ exception throwing
-- methods, but could use the unwind instruction.
| ReadNone
-- | This attribute indicates that the function does not write through any
-- pointer arguments (including byval arguments) or otherwise modify any
-- state (e.g. memory, control registers, etc) visible to caller functions.
-- It may dereference pointer arguments and read state that may be set in
-- the caller. A readonly function always returns the same value (or unwinds
-- an exception identically) when called with the same set of arguments and
-- global state. It cannot unwind an exception by calling the C++ exception
-- throwing methods, but may use the unwind instruction.
| ReadOnly
-- | This attribute indicates that the function should emit a stack smashing
-- protector. It is in the form of a \"canary\"—a random value placed on the
-- stack before the local variables that's checked upon return from the
-- function to see if it has been overwritten. A heuristic is used to
-- determine if a function needs stack protectors or not.
--
-- If a function that has an ssp attribute is inlined into a function that
-- doesn't have an ssp attribute, then the resulting function will have an
-- ssp attribute.
| Ssp
-- | This attribute indicates that the function should always emit a stack
-- smashing protector. This overrides the ssp function attribute.
--
-- If a function that has an sspreq attribute is inlined into a function
-- that doesn't have an sspreq attribute or which has an ssp attribute,
-- then the resulting function will have an sspreq attribute.
| SspReq
-- | This attribute indicates that the code generator should not use a red
-- zone, even if the target-specific ABI normally permits it.
| NoRedZone
-- | This attributes disables implicit floating point instructions.
| NoImplicitFloat
-- | This attribute disables prologue / epilogue emission for the function.
-- This can have very system-specific consequences.
| Naked
deriving (Eq)
instance Outputable LlvmFuncAttr where
ppr AlwaysInline = text "alwaysinline"
ppr InlineHint = text "inlinehint"
ppr NoInline = text "noinline"
ppr OptSize = text "optsize"
ppr NoReturn = text "noreturn"
ppr NoUnwind = text "nounwind"
ppr ReadNone = text "readnone"
ppr ReadOnly = text "readonly"
ppr Ssp = text "ssp"
ppr SspReq = text "ssqreq"
ppr NoRedZone = text "noredzone"
ppr NoImplicitFloat = text "noimplicitfloat"
ppr Naked = text "naked"
-- | Different types to call a function.
data LlvmCallType
-- | Normal call, allocate a new stack frame.
= StdCall
-- | Tail call, perform the call in the current stack frame.
| TailCall
deriving (Eq,Show)
-- | Different calling conventions a function can use.
data LlvmCallConvention
-- | The C calling convention.
-- This calling convention (the default if no other calling convention is
-- specified) matches the target C calling conventions. This calling
-- convention supports varargs function calls and tolerates some mismatch in
-- the declared prototype and implemented declaration of the function (as
-- does normal C).
= CC_Ccc
-- | This calling convention attempts to make calls as fast as possible
-- (e.g. by passing things in registers). This calling convention allows
-- the target to use whatever tricks it wants to produce fast code for the
-- target, without having to conform to an externally specified ABI
-- (Application Binary Interface). Implementations of this convention should
-- allow arbitrary tail call optimization to be supported. This calling
-- convention does not support varargs and requires the prototype of al
-- callees to exactly match the prototype of the function definition.
| CC_Fastcc
-- | This calling convention attempts to make code in the caller as efficient
-- as possible under the assumption that the call is not commonly executed.
-- As such, these calls often preserve all registers so that the call does
-- not break any live ranges in the caller side. This calling convention
-- does not support varargs and requires the prototype of all callees to
-- exactly match the prototype of the function definition.
| CC_Coldcc
-- | The GHC-specific 'registerised' calling convention.
| CC_Ghc
-- | Any calling convention may be specified by number, allowing
-- target-specific calling conventions to be used. Target specific calling
-- conventions start at 64.
| CC_Ncc Int
-- | X86 Specific 'StdCall' convention. LLVM includes a specific alias for it
-- rather than just using CC_Ncc.
| CC_X86_Stdcc
deriving (Eq)
instance Outputable LlvmCallConvention where
ppr CC_Ccc = text "ccc"
ppr CC_Fastcc = text "fastcc"
ppr CC_Coldcc = text "coldcc"
ppr CC_Ghc = text "ghccc"
ppr (CC_Ncc i) = text "cc " <> ppr i
ppr CC_X86_Stdcc = text "x86_stdcallcc"
-- | Functions can have a fixed amount of parameters, or a variable amount.
data LlvmParameterListType
-- Fixed amount of arguments.
= FixedArgs
-- Variable amount of arguments.
| VarArgs
deriving (Eq,Show)
-- | Linkage type of a symbol.
--
-- The description of the constructors is copied from the Llvm Assembly Language
-- Reference Manual <http://www.llvm.org/docs/LangRef.html#linkage>, because
-- they correspond to the Llvm linkage types.
data LlvmLinkageType
-- | Global values with internal linkage are only directly accessible by
-- objects in the current module. In particular, linking code into a module
-- with an internal global value may cause the internal to be renamed as
-- necessary to avoid collisions. Because the symbol is internal to the
-- module, all references can be updated. This corresponds to the notion
-- of the @static@ keyword in C.
= Internal
-- | Globals with @linkonce@ linkage are merged with other globals of the
-- same name when linkage occurs. This is typically used to implement
-- inline functions, templates, or other code which must be generated
-- in each translation unit that uses it. Unreferenced linkonce globals are
-- allowed to be discarded.
| LinkOnce
-- | @weak@ linkage is exactly the same as linkonce linkage, except that
-- unreferenced weak globals may not be discarded. This is used for globals
-- that may be emitted in multiple translation units, but that are not
-- guaranteed to be emitted into every translation unit that uses them. One
-- example of this are common globals in C, such as @int X;@ at global
-- scope.
| Weak
-- | @appending@ linkage may only be applied to global variables of pointer
-- to array type. When two global variables with appending linkage are
-- linked together, the two global arrays are appended together. This is
-- the Llvm, typesafe, equivalent of having the system linker append
-- together @sections@ with identical names when .o files are linked.
| Appending
-- | The semantics of this linkage follow the ELF model: the symbol is weak
-- until linked, if not linked, the symbol becomes null instead of being an
-- undefined reference.
| ExternWeak
-- | The symbol participates in linkage and can be used to resolve external
-- symbol references.
| ExternallyVisible
-- | Alias for 'ExternallyVisible' but with explicit textual form in LLVM
-- assembly.
| External
-- | Symbol is private to the module and should not appear in the symbol table
| Private
deriving (Eq)
instance Outputable LlvmLinkageType where
ppr Internal = text "internal"
ppr LinkOnce = text "linkonce"
ppr Weak = text "weak"
ppr Appending = text "appending"
ppr ExternWeak = text "extern_weak"
-- ExternallyVisible does not have a textual representation, it is
-- the linkage type a function resolves to if no other is specified
-- in Llvm.
ppr ExternallyVisible = empty
ppr External = text "external"
ppr Private = text "private"
-- -----------------------------------------------------------------------------
-- * LLVM Operations
--
-- | Llvm binary operators machine operations.
data LlvmMachOp
= LM_MO_Add -- ^ add two integer, floating point or vector values.
| LM_MO_Sub -- ^ subtract two ...
| LM_MO_Mul -- ^ multiply ..
| LM_MO_UDiv -- ^ unsigned integer or vector division.
| LM_MO_SDiv -- ^ signed integer ..
| LM_MO_URem -- ^ unsigned integer or vector remainder (mod)
| LM_MO_SRem -- ^ signed ...
| LM_MO_FAdd -- ^ add two floating point or vector values.
| LM_MO_FSub -- ^ subtract two ...
| LM_MO_FMul -- ^ multiply ...
| LM_MO_FDiv -- ^ divide ...
| LM_MO_FRem -- ^ remainder ...
-- | Left shift
| LM_MO_Shl
-- | Logical shift right
-- Shift right, filling with zero
| LM_MO_LShr
-- | Arithmetic shift right
-- The most significant bits of the result will be equal to the sign bit of
-- the left operand.
| LM_MO_AShr
| LM_MO_And -- ^ AND bitwise logical operation.
| LM_MO_Or -- ^ OR bitwise logical operation.
| LM_MO_Xor -- ^ XOR bitwise logical operation.
deriving (Eq)
instance Outputable LlvmMachOp where
ppr LM_MO_Add = text "add"
ppr LM_MO_Sub = text "sub"
ppr LM_MO_Mul = text "mul"
ppr LM_MO_UDiv = text "udiv"
ppr LM_MO_SDiv = text "sdiv"
ppr LM_MO_URem = text "urem"
ppr LM_MO_SRem = text "srem"
ppr LM_MO_FAdd = text "fadd"
ppr LM_MO_FSub = text "fsub"
ppr LM_MO_FMul = text "fmul"
ppr LM_MO_FDiv = text "fdiv"
ppr LM_MO_FRem = text "frem"
ppr LM_MO_Shl = text "shl"
ppr LM_MO_LShr = text "lshr"
ppr LM_MO_AShr = text "ashr"
ppr LM_MO_And = text "and"
ppr LM_MO_Or = text "or"
ppr LM_MO_Xor = text "xor"
-- | Llvm compare operations.
data LlvmCmpOp
= LM_CMP_Eq -- ^ Equal (Signed and Unsigned)
| LM_CMP_Ne -- ^ Not equal (Signed and Unsigned)
| LM_CMP_Ugt -- ^ Unsigned greater than
| LM_CMP_Uge -- ^ Unsigned greater than or equal
| LM_CMP_Ult -- ^ Unsigned less than
| LM_CMP_Ule -- ^ Unsigned less than or equal
| LM_CMP_Sgt -- ^ Signed greater than
| LM_CMP_Sge -- ^ Signed greater than or equal
| LM_CMP_Slt -- ^ Signed less than
| LM_CMP_Sle -- ^ Signed less than or equal
-- Float comparisons. GHC uses a mix of ordered and unordered float
-- comparisons.
| LM_CMP_Feq -- ^ Float equal
| LM_CMP_Fne -- ^ Float not equal
| LM_CMP_Fgt -- ^ Float greater than
| LM_CMP_Fge -- ^ Float greater than or equal
| LM_CMP_Flt -- ^ Float less than
| LM_CMP_Fle -- ^ Float less than or equal
deriving (Eq)
instance Outputable LlvmCmpOp where
ppr LM_CMP_Eq = text "eq"
ppr LM_CMP_Ne = text "ne"
ppr LM_CMP_Ugt = text "ugt"
ppr LM_CMP_Uge = text "uge"
ppr LM_CMP_Ult = text "ult"
ppr LM_CMP_Ule = text "ule"
ppr LM_CMP_Sgt = text "sgt"
ppr LM_CMP_Sge = text "sge"
ppr LM_CMP_Slt = text "slt"
ppr LM_CMP_Sle = text "sle"
ppr LM_CMP_Feq = text "oeq"
ppr LM_CMP_Fne = text "une"
ppr LM_CMP_Fgt = text "ogt"
ppr LM_CMP_Fge = text "oge"
ppr LM_CMP_Flt = text "olt"
ppr LM_CMP_Fle = text "ole"
-- | Llvm cast operations.
data LlvmCastOp
= LM_Trunc -- ^ Integer truncate
| LM_Zext -- ^ Integer extend (zero fill)
| LM_Sext -- ^ Integer extend (sign fill)
| LM_Fptrunc -- ^ Float truncate
| LM_Fpext -- ^ Float extend
| LM_Fptoui -- ^ Float to unsigned Integer
| LM_Fptosi -- ^ Float to signed Integer
| LM_Uitofp -- ^ Unsigned Integer to Float
| LM_Sitofp -- ^ Signed Int to Float
| LM_Ptrtoint -- ^ Pointer to Integer
| LM_Inttoptr -- ^ Integer to Pointer
| LM_Bitcast -- ^ Cast between types where no bit manipulation is needed
deriving (Eq)
instance Outputable LlvmCastOp where
ppr LM_Trunc = text "trunc"
ppr LM_Zext = text "zext"
ppr LM_Sext = text "sext"
ppr LM_Fptrunc = text "fptrunc"
ppr LM_Fpext = text "fpext"
ppr LM_Fptoui = text "fptoui"
ppr LM_Fptosi = text "fptosi"
ppr LM_Uitofp = text "uitofp"
ppr LM_Sitofp = text "sitofp"
ppr LM_Ptrtoint = text "ptrtoint"
ppr LM_Inttoptr = text "inttoptr"
ppr LM_Bitcast = text "bitcast"
-- -----------------------------------------------------------------------------
-- * Floating point conversion
--
-- | Convert a Haskell Double to an LLVM hex encoded floating point form. In
-- Llvm float literals can be printed in a big-endian hexadecimal format,
-- regardless of underlying architecture.
--
-- See Note [LLVM Float Types].
ppDouble :: Double -> SDoc
ppDouble d
= let bs = doubleToBytes d
hex d' = case showHex d' "" of
[] -> error "dToStr: too few hex digits for float"
[x] -> ['0',x]
[x,y] -> [x,y]
_ -> error "dToStr: too many hex digits for float"
in sdocWithDynFlags (\dflags ->
let fixEndian = if wORDS_BIGENDIAN dflags then id else reverse
str = map toUpper $ concat $ fixEndian $ map hex bs
in text "0x" <> text str)
-- Note [LLVM Float Types]
-- ~~~~~~~~~~~~~~~~~~~~~~~
-- We use 'ppDouble' for both printing Float and Double floating point types. This is
-- as LLVM expects all floating point constants (single & double) to be in IEEE
-- 754 Double precision format. However, for single precision numbers (Float)
-- they should be *representable* in IEEE 754 Single precision format. So the
-- easiest way to do this is to narrow and widen again.
-- (i.e., Double -> Float -> Double). We must be careful doing this that GHC
-- doesn't optimize that away.
-- Note [narrowFp & widenFp]
-- ~~~~~~~~~~~~~~~~~~~~~~~~~
-- NOTE: we use float2Double & co directly as GHC likes to optimize away
-- successive calls of 'realToFrac', defeating the narrowing. (Bug #7600).
-- 'realToFrac' has inconsistent behaviour with optimisation as well that can
-- also cause issues, these methods don't.
narrowFp :: Double -> Float
{-# NOINLINE narrowFp #-}
narrowFp = double2Float
widenFp :: Float -> Double
{-# NOINLINE widenFp #-}
widenFp = float2Double
ppFloat :: Float -> SDoc
ppFloat = ppDouble . widenFp
--------------------------------------------------------------------------------
-- * Misc functions
--------------------------------------------------------------------------------
ppCommaJoin :: (Outputable a) => [a] -> SDoc
ppCommaJoin strs = hsep $ punctuate comma (map ppr strs)
ppSpaceJoin :: (Outputable a) => [a] -> SDoc
ppSpaceJoin strs = hsep (map ppr strs)
|