{-
GHC 9.12.2
gcc (GCC) 15.2.1 20250813

(also reproducible on play.haskell.org with GHC 9.12.2)

ghc -O0 fails with the following assembler error
Error: operand type mismatch for `movsd'
    |
101 |         movsd %rbx,%rcx
    | ^

ghc -O1 succeeds

ghc -O2 fails with the following assembler error
/tmp/ghc20360_tmp_0_0/ghc_tmp_0_1.s: Assembler messages:
/tmp/ghc20360_tmp_0_0/ghc_tmp_0_1.s:103:0: error:
     Error: operand type mismatch for `movsd'
    |
103 |         movsd %rsi,%r8
    | ^

/tmp/ghc20360_tmp_0_0/ghc_tmp_0_1.s:106:0: error:
     Error: operand type mismatch for `movsd'
    |
106 |         movsd %rbx,%rdx
    | ^

/tmp/ghc20360_tmp_0_0/ghc_tmp_0_1.s:116:0: error:
     Error: operand type mismatch for `movsd'
    |
116 |         movsd %rbx,%rsi
    | ^

<no location info>: error:
    `gcc' failed in phase `Assembler'. (Exit code: 1)

-}

{-# LANGUAGE MagicHash #-}
{-# LANGUAGE UnboxedTuples #-}

module Wat where

import qualified GHC.Base as B

int16ToInt64# :: B.Int16# -> B.Int64#
int16ToInt64# n = B.intToInt64# (B.int16ToInt# n)

int64ToInt16# :: B.Int64# -> B.Int16#
int64ToInt16# n = B.intToInt16# (B.int64ToInt# n)

liftA2_I16_I64X2 :: (B.Int16# -> B.Int16# -> B.Int16#) -> B.Int64X2# ->  B.Int64X2# -> B.Int64X2#
liftA2_I16_I64X2 f a b = let
  !(# al, ar #) = B.unpackInt64X2# a
  !(# bl, br #) = B.unpackInt64X2# b
  al16 = int64ToInt16# al
  ar16 = int64ToInt16# ar
  bl16 = int64ToInt16# bl
  br16 = int64ToInt16# br
  xl = int16ToInt64# (f al16 bl16)
  xr = int16ToInt64# (f ar16 br16)
  in B.packInt64X2# (# xl, xr #)