On Tue, Feb 27, 2024 at 12:32:48PM -0500, Daneel Yaitskov wrote:
the intel manual defines function prototypes as normal:
__m128i _mm_bsrli_si128 (__m128i a, int imm8)
Using a variable as second argument in _mm_bsrli_si128 produces unclear, but compilation error with exact line number. [...] Haskell is known as one of the best languages in type acrobatics, but could it beat C here?
Sure, you can use Template Haskell for this. Use of `wellFormedBsrli` ensures that its second argument is always evaluated at compile time. See the output from GHC below for confirmation of this. Tom {-# LANGUAGE TemplateHaskell #-} module A where import Language.Haskell.TH import Language.Haskell.TH.Syntax bsrli :: Int -> Int -> Int bsrli = error "Implement bsrli here, using FFI, I guess" wellFormedBsrli :: Quote m => Int -> Code m (Int -> Int) wellFormedBsrli y = [|| \x -> bsrli x $$(liftTyped y) ||] {-# LANGUAGE TemplateHaskell #-} {-# OPTIONS_GHC -ddump-splices #-} module B where import A example :: Int example = $$(wellFormedBsrli (3 + 2)) 0x1 ghc B.hs -ddump-splices [1 of 2] Compiling A ( A.hs, A.o, A.dyn_o ) [Source file changed] [2 of 2] Compiling B ( B.hs, B.o, B.dyn_o ) [A[TH] changed] B.hs:9:5-29: Splicing expression wellFormedBsrli (3 + 2) ======> \ x_a2zf -> (bsrli x_a2zf) 5