;; `select`/`bitselect`-related rewrites
;; remove select when both choices are the same
(rule (simplify (select ty _ x x)) (subsume x))
(rule (simplify (bitselect ty _ x x)) (subsume x))
;; Push zeroes to the right -- this makes the select `truthy`, as used elsewhere
;; if icmp { 0 } else { nonzero } => if !icmp { nonzero } else { 0 }
(rule (simplify (select sty (icmp cty cc x y)
zero @ (iconst_u _ 0)
nonzero @ (iconst_u _ (u64_when_non_zero))))
(select sty (icmp cty (intcc_complement cc) x y) nonzero zero))
;; if icmp(x, y) { 1 } else { 0 } => uextend(icmp(x, y))
(rule (simplify (select ty cmp @ (icmp _ cc x y)
(iconst_u _ 1)
(iconst_u _ 0)))
(uextend_maybe ty cmp))
;; if icmp(x, y) { -1 } else { 0 } => uextend(icmp(x, y))
(rule (simplify (select ty cmp@(icmp _ cc x y)
(iconst_s _ -1)
(iconst_s _ 0)))
(bmask ty cmp))
;; Transform select-of-icmp into {u,s}{min,max} instructions where possible.
(rule (simplify (select ty (sgt _ x y) x y)) (smax ty x y))
(rule (simplify (select ty (sge _ x y) x y)) (smax ty x y))
(rule (simplify (select ty (ugt _ x y) x y)) (umax ty x y))
(rule (simplify (select ty (uge _ x y) x y)) (umax ty x y))
(rule (simplify (select ty (slt _ x y) x y)) (smin ty x y))
(rule (simplify (select ty (sle _ x y) x y)) (smin ty x y))
(rule (simplify (select ty (ult _ x y) x y)) (umin ty x y))
(rule (simplify (select ty (ule _ x y) x y)) (umin ty x y))
;; These are the same rules as above, but when the operands for select are swapped
(rule (simplify (select ty (slt _ x y) y x)) (smax ty x y))
(rule (simplify (select ty (sle _ x y) y x)) (smax ty x y))
(rule (simplify (select ty (ult _ x y) y x)) (umax ty x y))
(rule (simplify (select ty (ule _ x y) y x)) (umax ty x y))
(rule (simplify (select ty (sgt _ x y) y x)) (smin ty x y))
(rule (simplify (select ty (sge _ x y) y x)) (smin ty x y))
(rule (simplify (select ty (ugt _ x y) y x)) (umin ty x y))
(rule (simplify (select ty (uge _ x y) y x)) (umin ty x y))
;; Transform bitselect-of-icmp into {u,s}{min,max} instructions where possible.
(rule (simplify (bitselect ty @ (multi_lane _ _) (sgt _ x y) x y)) (smax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (sge _ x y) x y)) (smax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (ugt _ x y) x y)) (umax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (uge _ x y) x y)) (umax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (slt _ x y) x y)) (smin ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (sle _ x y) x y)) (smin ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (ult _ x y) x y)) (umin ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (ule _ x y) x y)) (umin ty x y))
;; These are the same rules as above, but when the operands for select are swapped
(rule (simplify (bitselect ty @ (multi_lane _ _) (slt _ x y) y x)) (smax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (sle _ x y) y x)) (smax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (ult _ x y) y x)) (umax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (ule _ x y) y x)) (umax ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (sgt _ x y) y x)) (smin ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (sge _ x y) y x)) (smin ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (ugt _ x y) y x)) (umin ty x y))
(rule (simplify (bitselect ty @ (multi_lane _ _) (uge _ x y) y x)) (umin ty x y))
;; (c & x) | (~c & y) -> (bitselect c x y)
;; These are all the same rule, just with different permutations of the operands
;;
;; We currently only match vectors since scalar floats and i128's are not supported
;; in some backends.
(rule (simplify (bor (ty_vec128 ty) (band ty c x) (band ty (bnot ty c) y))) (bitselect ty c x y))
(rule (simplify (bor (ty_vec128 ty) (band ty c x) (band ty y (bnot ty c) ))) (bitselect ty c x y))
(rule (simplify (bor (ty_vec128 ty) (band ty x c) (band ty (bnot ty c) y))) (bitselect ty c x y))
(rule (simplify (bor (ty_vec128 ty) (band ty x c) (band ty y (bnot ty c) ))) (bitselect ty c x y))
(rule (simplify (bor (ty_vec128 ty) (band ty (bnot ty c) y) (band ty c x))) (bitselect ty c x y))
(rule (simplify (bor (ty_vec128 ty) (band ty (bnot ty c) y) (band ty x c))) (bitselect ty c x y))
(rule (simplify (bor (ty_vec128 ty) (band ty y (bnot ty c)) (band ty c x))) (bitselect ty c x y))
(rule (simplify (bor (ty_vec128 ty) (band ty y (bnot ty c)) (band ty x c))) (bitselect ty c x y))
;; Lift an extend operation outside of a `select` if the extend is happening
;; on both the consequent and the alternative.
(rule (simplify (select ty cond
(uextend ty a @ (value_type small))
(uextend ty b @ (value_type small))))
(uextend ty (select small cond a b)))
(rule (simplify (select ty cond
(sextend ty a @ (value_type small))
(sextend ty b @ (value_type small))))
(sextend ty (select small cond a b)))
(rule (simplify (select ty (sgt _ x (iconst_u ty 0)) x (ineg ty x))) (subsume (iabs ty x)))
(rule (simplify (select ty (sge _ x (iconst_u ty 0)) x (ineg ty x))) (subsume (iabs ty x)))
(rule (simplify (select ty (sle _ x (iconst_u ty 0)) (ineg ty x) x)) (subsume (iabs ty x)))
(rule (simplify (select ty (slt _ x (iconst_u ty 0)) (ineg ty x) x)) (subsume (iabs ty x)))
;; fold add-select to select-add
(rule (simplify
(iadd ty (select ty c (iconst_u ty x) (iconst_u ty y)) (iconst_u ty z)))
(select ty c
(iconst ty (imm64_masked ty (u64_wrapping_add x z)))
(iconst ty (imm64_masked ty (u64_wrapping_add y z)))))
(rule (simplify (select ty d a (select ty d _ y))) (select ty d a y))
(rule (simplify (select ty d (select ty d x _) a)) (select ty d x a))
;; min x y < x => false and its commutative versions
(rule (simplify (sgt (fits_in_64 ty) (smin _ x y) x)) (iconst_u ty 0))
(rule (simplify (sgt (fits_in_64 ty) (smin _ x y) y)) (iconst_u ty 0))
(rule (simplify (slt (fits_in_64 ty) x (smin _ x z))) (iconst_u ty 0))
(rule (simplify (slt (fits_in_64 ty) x (smin _ y x))) (iconst_u ty 0))
(rule (simplify (ugt (fits_in_64 ty) (umin _ x y) x)) (iconst_u ty 0))
(rule (simplify (ugt (fits_in_64 ty) (umin _ x y) y)) (iconst_u ty 0))
(rule (simplify (ult (fits_in_64 ty) x (umin _ x z))) (iconst_u ty 0))
(rule (simplify (ult (fits_in_64 ty) x (umin _ y x))) (iconst_u ty 0))
;; (x == y) ? x : y => y
;; select(eq/ne) patterns that always collapse to y.
(rule (simplify (select ty (eq cty x y) x y)) (subsume y))
(rule (simplify (select ty (ne cty x y) y x)) (subsume y))
(rule (simplify (select ty (eq cty y x) x y)) (subsume y))
(rule (simplify (select ty (ne cty y x) y x)) (subsume y))
;; (x | (y != z)) ? y : z ==> y
(rule (simplify (select ty (bor cty x (ne cty y z)) y z)) (subsume y))
(rule (simplify (select ty (bor cty (ne cty y z) x) y z)) (subsume y))
(rule (simplify (select ty (bor cty x (ne cty z y)) y z)) (subsume y))
(rule (simplify (select ty (bor cty (ne cty z y) x) y z)) (subsume y))
;; (x == y) ? x : (x | y) ==> (x | y)
;; and equivalent operand-order variants.
(rule (simplify (select ty (eq cty x y) x (bor ty x y))) (bor ty x y))
(rule (simplify (select ty (ne cty x y) (bor ty x y) x)) (bor ty x y))
(rule (simplify (select ty (eq cty x y) x (bor ty y x))) (bor ty x y))
(rule (simplify (select ty (ne cty x y) (bor ty y x) x)) (bor ty x y))
(rule (simplify (select ty (eq cty y x) x (bor ty x y))) (bor ty x y))
(rule (simplify (select ty (ne cty y x) (bor ty x y) x)) (bor ty x y))
(rule (simplify (select ty (eq cty y x) x (bor ty y x))) (bor ty x y))
(rule (simplify (select ty (ne cty y x) (bor ty y x) x)) (bor ty x y))
;; (x != y) ? (x & y) : y ==> (x & y)
;; and equivalent operand-order variants.
(rule (simplify (select ty (ne cty x y) (band ty x y) y)) (band ty x y))
(rule (simplify (select ty (eq cty x y) y (band ty x y))) (band ty x y))
(rule (simplify (select ty (ne cty x y) (band ty y x) y)) (band ty x y))
(rule (simplify (select ty (eq cty x y) y (band ty y x))) (band ty x y))
(rule (simplify (select ty (ne cty y x) (band ty x y) y)) (band ty x y))
(rule (simplify (select ty (eq cty y x) y (band ty x y))) (band ty x y))
(rule (simplify (select ty (ne cty y x) (band ty y x) y)) (band ty x y))
(rule (simplify (select ty (eq cty y x) y (band ty y x))) (band ty x y))
;; (x <_u y) ? 1 : (x == y) ==> (x <=_u y)
;; and equivalent operand-order variants.
(rule (simplify (select ty (ult cty x y) (iconst_u ty 1) (eq ty x y))) (ule ty x y))
(rule (simplify (select ty (uge cty x y) (eq ty x y) (iconst_u ty 1))) (ule ty x y))
(rule (simplify (select ty (ugt cty y x) (iconst_u ty 1) (eq ty x y))) (ule ty x y))
(rule (simplify (select ty (ule cty y x) (eq ty x y) (iconst_u ty 1))) (ule ty x y))
(rule (simplify (select ty (ult cty x y) (iconst_u ty 1) (eq ty y x))) (ule ty x y))
(rule (simplify (select ty (uge cty x y) (eq ty y x) (iconst_u ty 1))) (ule ty x y))
(rule (simplify (select ty (ugt cty y x) (iconst_u ty 1) (eq ty y x))) (ule ty x y))
(rule (simplify (select ty (ule cty y x) (eq ty y x) (iconst_u ty 1))) (ule ty x y))
;; (x < y) ? 1 : (x > y) ==> (x != y)
;; and equivalent operand-order variants.
(rule (simplify (select ty (slt cty x y) (iconst_u ty 1) (sgt ty x y))) (ne ty x y))
(rule (simplify (select ty (sge cty x y) (sgt ty x y) (iconst_u ty 1))) (ne ty x y))
(rule (simplify (select ty (sgt cty y x) (iconst_u ty 1) (sgt ty x y))) (ne ty x y))
(rule (simplify (select ty (sle cty y x) (sgt ty x y) (iconst_u ty 1))) (ne ty x y))
(rule (simplify (select ty (slt cty x y) (iconst_u ty 1) (slt ty y x))) (ne ty x y))
(rule (simplify (select ty (sge cty x y) (slt ty y x) (iconst_u ty 1))) (ne ty x y))
(rule (simplify (select ty (sgt cty y x) (iconst_u ty 1) (slt ty y x))) (ne ty x y))
(rule (simplify (select ty (sle cty y x) (slt ty y x) (iconst_u ty 1))) (ne ty x y))
(rule (simplify (select ty (ult cty x y) (iconst_u ty 1) (ugt ty x y))) (ne ty x y))
(rule (simplify (select ty (uge cty x y) (ugt ty x y) (iconst_u ty 1))) (ne ty x y))
(rule (simplify (select ty (ugt cty y x) (iconst_u ty 1) (ugt ty x y))) (ne ty x y))
(rule (simplify (select ty (ule cty y x) (ugt ty x y) (iconst_u ty 1))) (ne ty x y))
(rule (simplify (select ty (ult cty x y) (iconst_u ty 1) (ult ty y x))) (ne ty x y))
(rule (simplify (select ty (uge cty x y) (ult ty y x) (iconst_u ty 1))) (ne ty x y))
(rule (simplify (select ty (ugt cty y x) (iconst_u ty 1) (ult ty y x))) (ne ty x y))
(rule (simplify (select ty (ule cty y x) (ult ty y x) (iconst_u ty 1))) (ne ty x y))
;; (x ? 1 : (x | y)) ==> (x ? 1 : y)
(rule (simplify (select ty x (iconst_u ty 1) (bor ty x y))) (select ty x (iconst_u ty 1) y))
(rule (simplify (select ty x (iconst_u ty 1) (bor ty y x))) (select ty x (iconst_u ty 1) y))
;; if x == n then (y - n) else (y - x) ==> (y - x)
;; and equivalent predicate/operand-order variants.
(rule (simplify (select ty (eq cty x (iconst_u ty n)) (isub ty y (iconst_u ty n)) (isub ty y x))) (isub ty y x))
(rule (simplify (select ty (ne cty x (iconst_u ty n)) (isub ty y x) (isub ty y (iconst_u ty n)))) (isub ty y x))
(rule (simplify (select ty (eq cty (iconst_u ty n) x) (isub ty y (iconst_u ty n)) (isub ty y x))) (isub ty y x))
(rule (simplify (select ty (ne cty (iconst_u ty n) x) (isub ty y x) (isub ty y (iconst_u ty n)))) (isub ty y x))
;; select(cond, eq(z, y), eq(p, y)) ==> eq(y, select(cond, z, p))
(rule (simplify (select ty x (eq ty z y) (eq ty (iconst_u cty p) y))) (eq ty y (select cty x z (iconst_u cty p))))
(rule (simplify (select ty x (eq ty z y) (eq ty y (iconst_u cty p)))) (eq ty y (select cty x z (iconst_u cty p))))
(rule (simplify (select ty x (eq ty y z) (eq ty (iconst_u cty p) y))) (eq ty y (select cty x z (iconst_u cty p))))
(rule (simplify (select ty x (eq ty y z) (eq ty y (iconst_u cty p)))) (eq ty y (select cty x z (iconst_u cty p))))