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Fix uint32 extended precision multiplication

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Mamy André-Ratsimbazafy 2020-02-10 02:12:44 +01:00
parent 30f8756dfc
commit 3033ae30f8
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1 changed files with 3 additions and 1 deletions
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constantine/private/primitives_internal.nim
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@ -57,11 +57,13 @@ func unsafeExtendedPrecMul*(hi, lo: var Ct[uint64], a, b: Ct[uint64]) {.inline.}
else:
asm_x86_64_extMul(T(hi), T(lo), T(a), T(b))
import strutils
func unsafeExtendedPrecMul*(hi, lo: var Ct[uint32], a, b: Ct[uint32]) {.inline.}=
## Extended precision multiplication uint32 * uint32 --> uint32
let extMul = uint64(a) * uint64(b)
hi = (Ct[uint32])(extMul shr 32)
lo = (Ct[uint32])(extMul and 31)
lo = (Ct[uint32])(extMul and ((1'u64 shl 32) - 1))
func asm_x86_64_div2n1n(q, r: var uint64, n_hi, n_lo, d: uint64) {.inline.}=
## Division uint128 by uint64