GitLab

f75ab223

by Peter Trommler at 2025-10-31T18:43:13-04:00

ghc-toolchain: detect PowerPC 64 bit ABI

Check preprocessor macro defined for ABI v2 and assume v1 otherwise.
Fixes #26521

d086c474
by Peter Trommler at 2025-10-31T18:43:13-04:00
```
ghc-toolchain: refactor, move lastLine to Utils
```

@@ -21,6 +21,7 @@ library
                        GHC.Toolchain.NormaliseTriple,
                        GHC.Toolchain.CheckArm,
                        GHC.Toolchain.Target,
 +                      GHC.Toolchain.CheckPower
                        GHC.Toolchain.Tools.Ar,
                        GHC.Toolchain.Tools.Cc,
                        GHC.Toolchain.Tools.Cxx,

@@ -8,6 +8,7 @@ import System.Process
  import GHC.Platform.ArchOS
  import GHC.Toolchain.Prelude
 +import GHC.Toolchain.Utils (lastLine)
  import GHC.Toolchain.Tools.Cc
  -- | Awkwardly, ARM triples sometimes contain insufficient information about
@@ -75,10 +76,6 @@ findArmIsa cc = do
            "False" -> return False
            _ -> throwE $ "unexpected output from test program: " ++ out
 -lastLine :: String -> String
 -lastLine "" = ""
 -lastLine s  = last $ lines s
+-
  -- | Raspbian unfortunately makes some extremely questionable packaging
  -- decisions, configuring gcc to compile for ARMv6 despite the fact that the
  -- Raspberry Pi 4 is ARMv8. As ARMv8 doesn't support all instructions supported

 +module GHC.Toolchain.CheckPower ( checkPowerAbi ) where
++
 +import GHC.Platform.ArchOS
++
 +import GHC.Toolchain.Prelude
 +import GHC.Toolchain.Utils (lastLine)
 +import GHC.Toolchain.Tools.Cc
++
 +-- 64-Bit ELF V2 ABI Specification, Power Architecture, Revision 1.5 says:
 +-- A C preprocessor that conforms to this ABI shall predefine the macro
 +-- _CALL_ELF to have a value of 2 (Section 5.1.4 Predifined Macros).
 +-- The 64-bit PowerPC ELF Application Binary Interface Supplement 1.9
 +-- does not define any macro to identify the ABI.
 +-- So we check for ABI version 2 and default to ABI version 1.
++
 +checkPowerAbi :: Cc -> M Arch
 +checkPowerAbi cc = do
 +  checking "POWER ELF ABI" $ do
 +    out <- fmap lastLine $ preprocess cc $ unlines
 +        [ "#if defined(_CALL_ELF) && _CALL_ELF == 2"
 +        , "ELFv2"
 +        , "#else"
 +        , "ELFv1"
 +        , "#endif"
 +        ]
 +    case out of
 +      "ELFv1" -> pure $ ArchPPC_64 ELF_V1
 +      "ELFv2" -> pure $ ArchPPC_64 ELF_V2
 +      _       -> throwE $ "unexpected output from test program: " ++ out

@@ -6,6 +6,7 @@ import GHC.Platform.ArchOS
  import GHC.Toolchain.Prelude
  import GHC.Toolchain.CheckArm
 +import GHC.Toolchain.CheckPower
  import GHC.Toolchain.Tools.Cc
  -- | Parse a triple `arch-vendor-os` into an 'ArchOS' and a vendor name 'String'
@@ -40,7 +41,7 @@ parseArch cc arch =
        "x86_64" -> pure ArchX86_64
        "amd64" -> pure ArchX86_64
        "powerpc" -> pure ArchPPC
 -      "powerpc64" -> pure (ArchPPC_64 ELF_V1)
 +      "powerpc64" -> checkPowerAbi cc
        "powerpc64le" -> pure (ArchPPC_64 ELF_V2)
        "s390x" -> pure ArchS390X
        "arm" -> findArmIsa cc

@@ -8,6 +8,7 @@ module GHC.Toolchain.Utils
      , oneOf
      , oneOf'
      , isSuccess
 +    , lastLine
      ) where
  import Control.Exception
@@ -65,3 +66,6 @@ isSuccess = \case
    ExitSuccess -> True
    ExitFailure _ -> False
 +lastLine :: String -> String
 +lastLine "" = ""
 +lastLine s  = last $ lines s