constantine/helpers/static_for.nim
Mamy Ratsimbazafy 2613356281
Endomorphism acceleration for Scalar Multiplication (#44)
* Add MultiScalar recoding from "Efficient and Secure Algorithms for GLV-Based Scalar Multiplication" by Faz et al

* precompute cube root of unity - Add VM precomputation of Fp - workaround upstream bug https://github.com/nim-lang/Nim/issues/14585

* Add the φ-accelerated lookup table builder

* Add a dedicated bithacks file

* cosmetic import consistency

* Build the φ precompute table with n-1 EC additions instead of 2^(n-1) additions

* remove binary

* Add the GLV precomputations to the sage scripts

* You can't avoid it, bigint multiplication is needed at one point

* Add bigint multiplication discarding some low words

* Implement the lattice decomposition in sage

* Proper decomposition for BN254

* Prepare the code for a new scalar mul

* We compile, and now debugging hunt

* More helpers to debug GLV scalar Mul

* Fix conditional negation

* Endomorphism accelerated scalar mul working for BN254 curve

* Implement endomorphism acceleration for BLS12-381 (needed cofactor clearing of the point)

* fix nimble test script after bench rename
2020-06-14 15:39:06 +02:00

43 lines
1.2 KiB
Nim

import std/macros
proc replaceNodes(ast: NimNode, what: NimNode, by: NimNode): NimNode =
# Replace "what" ident node by "by"
proc inspect(node: NimNode): NimNode =
case node.kind:
of {nnkIdent, nnkSym}:
if node.eqIdent(what):
return by
return node
of nnkEmpty:
return node
of nnkLiterals:
return node
else:
var rTree = node.kind.newTree()
for child in node:
rTree.add inspect(child)
return rTree
result = inspect(ast)
macro staticFor*(idx: untyped{nkIdent}, start, stopEx: static int, body: untyped): untyped =
result = newStmtList()
for i in start ..< stopEx:
result.add nnkBlockStmt.newTree(
ident("unrolledIter_" & $idx & $i),
body.replaceNodes(idx, newLit i)
)
{.experimental: "dynamicBindSym".}
macro staticFor*(ident: untyped{nkIdent}, choices: typed, body: untyped): untyped =
## matches
## staticFor(curve, TestCurves):
## body
## and unroll the body for each curve in TestCurves
result = newStmtList()
for choice in choices:
result.add nnkBlockStmt.newTree(
ident($ident & "_" & $choice.intVal),
body.replaceNodes(ident, choice)
)