{-# LANGUAGE CPP #-}

-- ----------------------------------------------------------------------------
-- | Pretty print helpers for the LLVM Code generator.
--
module LlvmCodeGen.Ppr (
        pprLlvmHeader, pprLlvmCmmDecl, pprLlvmData, infoSection, iTableSuf
    ) where

#include "HsVersions.h"

import Llvm
import LlvmCodeGen.Base
import LlvmCodeGen.Data

import CLabel
import Cmm
import Platform

import FastString
import Outputable
import Unique


-- ----------------------------------------------------------------------------
-- * Top level
--

-- | Header code for LLVM modules
pprLlvmHeader :: SDoc
pprLlvmHeader = moduleLayout


-- | LLVM module layout description for the host target
moduleLayout :: SDoc
moduleLayout = sdocWithPlatform $ \platform ->
    case platform of
    Platform { platformArch = ArchX86, platformOS = OSDarwin } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32\""
        $+$ text "target triple = \"i386-apple-darwin9.8\""
    Platform { platformArch = ArchX86, platformOS = OSMinGW32 } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-f80:128:128-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32\""
        $+$ text "target triple = \"i686-pc-win32\""
    Platform { platformArch = ArchX86, platformOS = OSLinux } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:32:32-n8:16:32\""
        $+$ text "target triple = \"i386-pc-linux-gnu\""
    Platform { platformArch = ArchX86_64, platformOS = OSDarwin } ->
        text "target datalayout = \"e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64\""
        $+$ text "target triple = \"x86_64-apple-darwin10.0.0\""
    Platform { platformArch = ArchX86_64, platformOS = OSLinux } ->
        text "target datalayout = \"e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-s0:64:64-f80:128:128-n8:16:32:64\""
        $+$ text "target triple = \"x86_64-linux-gnu\""
    Platform { platformArch = ArchARM {}, platformOS = OSLinux } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:64:128-a0:0:64-n32\""
        $+$ text "target triple = \"arm-unknown-linux-gnueabi\""
    Platform { platformArch = ArchARM {}, platformOS = OSAndroid } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:64:128-a0:0:64-n32\""
        $+$ text "target triple = \"arm-unknown-linux-androideabi\""
    Platform { platformArch = ArchARM {}, platformOS = OSQNXNTO } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:64:128-a0:0:64-n32\""
        $+$ text "target triple = \"arm-unknown-nto-qnx8.0.0eabi\""
    Platform { platformArch = ArchARM {}, platformOS = OSiOS } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:64:128-a0:0:64-n32\""
        $+$ text "target triple = \"arm-apple-darwin10\""
    Platform { platformArch = ArchX86, platformOS = OSiOS } ->
        text "target datalayout = \"e-p:32:32:32-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:32:64-f32:32:32-f64:32:64-v64:64:64-v128:128:128-a0:0:64-f80:128:128-n8:16:32\""
        $+$ text "target triple = \"i386-apple-darwin11\""
    Platform { platformArch = ArchARM64, platformOS = OSiOS } ->
        text "target datalayout = \"e-p:64:64:64-i1:8:8-i8:8:8-i16:16:16-i32:32:32-i64:64:64-f32:32:32-f64:64:64-v64:64:64-v128:128:128-a0:0:64-n32:64-S128\""
        $+$ text "target triple = \"arm64-apple-ios7.0.0\""
    Platform { platformArch = ArchARM64, platformOS = OSLinux } ->
        text "target datalayout = \"e-m:e-i64:64-i128:128-n32:64-S128\""
        $+$ text "target triple = \"aarch64-unknown-linux-gnu\""
    _ ->
        if platformIsCrossCompiling platform
            then panic "LlvmCodeGen.Ppr: Cross compiling without valid target info."
            else empty
        -- If you see the above panic, GHC is missing the required target datalayout
        -- and triple information. You can obtain this info by compiling a simple
        -- 'hello world' C program with the clang C compiler eg:
        --     clang hello.c -emit-llvm -o hello.ll
        -- and the first two lines of hello.ll should provide the 'target datalayout'
        -- and 'target triple' lines required.


-- | Pretty print LLVM data code
pprLlvmData :: LlvmData -> SDoc
pprLlvmData (globals, types) =
    let ppLlvmTys (LMAlias    a) = ppLlvmAlias a
        ppLlvmTys (LMFunction f) = ppLlvmFunctionDecl f
        ppLlvmTys _other         = empty

        types'   = vcat $ map ppLlvmTys types
        globals' = ppLlvmGlobals globals
    in types' $+$ globals'


-- | Pretty print LLVM code
pprLlvmCmmDecl :: Int -> LlvmCmmDecl -> LlvmM (SDoc, [LlvmVar])
pprLlvmCmmDecl _ (CmmData _ lmdata)
  = return (vcat $ map pprLlvmData lmdata, [])

pprLlvmCmmDecl count (CmmProc mb_info entry_lbl live (ListGraph blks))
  = do (idoc, ivar) <- case mb_info of
                        Nothing -> return (empty, [])
                        Just (Statics info_lbl dat)
                         -> pprInfoTable count info_lbl (Statics entry_lbl dat)

       let sec = mkLayoutSection (count + 1)
           (lbl',sec') = case mb_info of
                           Nothing                   -> (entry_lbl, Nothing)
                           Just (Statics info_lbl _) -> (info_lbl,  sec)
           link = if externallyVisibleCLabel lbl'
                      then ExternallyVisible
                      else Internal
           lmblocks = map (\(BasicBlock id stmts) ->
                                LlvmBlock (getUnique id) stmts) blks

       fun <- mkLlvmFunc live lbl' link  sec' lmblocks
       let name = decName $ funcDecl fun
           defName = name `appendFS` fsLit "$def"
           funcDecl' = (funcDecl fun) { decName = defName }
           fun' = fun { funcDecl = funcDecl' }
           funTy = LMFunction funcDecl'
           funVar = LMGlobalVar name
                                (LMPointer funTy)
                                link
                                Nothing
                                Nothing
                                Alias
           defVar = LMGlobalVar defName
                                (LMPointer funTy)
                                (funcLinkage funcDecl')
                                (funcSect fun)
                                (funcAlign funcDecl')
                                Alias
           alias = LMGlobal funVar
                            (Just $ LMBitc (LMStaticPointer defVar)
                                           (LMPointer $ LMInt 8))

       return (ppLlvmGlobal alias $+$ idoc $+$ ppLlvmFunction fun', ivar)


-- | Pretty print CmmStatic
pprInfoTable :: Int -> CLabel -> CmmStatics -> LlvmM (SDoc, [LlvmVar])
pprInfoTable count info_lbl stat
  = do (ldata, ltypes) <- genLlvmData (Text, stat)

       dflags <- getDynFlags
       platform <- getLlvmPlatform
       let setSection :: LMGlobal -> LlvmM (LMGlobal, [LlvmVar])
           setSection (LMGlobal (LMGlobalVar _ ty l _ _ c) d) = do
             lbl <- strCLabel_llvm info_lbl
             let sec = mkLayoutSection count
                 ilabel = lbl `appendFS` fsLit iTableSuf
                 gv = LMGlobalVar ilabel ty l sec (llvmInfAlign dflags) c
                 -- See Note [Subsections Via Symbols]
                 v = if (platformHasSubsectionsViaSymbols platform
                         && l == ExternallyVisible)
                        || l == Internal
                     then [gv]
                     else []
             funInsert ilabel ty
             return (LMGlobal gv d, v)
           setSection v = return (v,[])

       (ldata', llvmUsed) <- unzip `fmap` mapM setSection ldata
       ldata'' <- mapM aliasify ldata'
       let modUsedLabel (LMGlobalVar name ty link sect align const) =
             LMGlobalVar (name `appendFS` fsLit "$def") ty link sect align const
           modUsedLabel v = v
           llvmUsed' = map modUsedLabel $ concat llvmUsed
       return (pprLlvmData (concat ldata'', ltypes), llvmUsed')


-- | We generate labels for info tables by converting them to the same label
-- as for the entry code but adding this string as a suffix.
iTableSuf :: String
iTableSuf = "_itable"


-- | Create a specially crafted section declaration that encodes the order this
-- section should be in the final object code.
--
-- The LlvmMangler.llvmFixupAsm pass over the assembly produced by LLVM uses
-- this section declaration to do its processing.
mkLayoutSection :: Int -> LMSection
mkLayoutSection n
  = Just (fsLit $ infoSection ++ show n)


-- | The section we are putting info tables and their entry code into, should
-- be unique since we process the assembly pattern matching this.
infoSection :: String
infoSection = "X98A__STRIP,__me"
