faster hashToG2 by using sparsity

mratsim · Jul 2, 2023 · c7e2180 · c7e2180
1 parent 2774f8b
commit c7e2180
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Showing 2 changed files with 8 additions and 10 deletions.
diff --git a/constantine/math/elliptic/ec_shortweierstrass_jacobian.nim b/constantine/math/elliptic/ec_shortweierstrass_jacobian.nim
@@ -295,8 +295,7 @@ template sumImpl[F; G: static Subgroup](
       a.square(HHH_or_Mpre, skipFinalSub = true)
       a *= HHH_or_Mpre              # a = 3X₁²
       b.square(Z1Z1)
-      # b.mulCheckSparse(CoefA)     # TODO: broken static compile-time type inference
-      b *= CoefA                    # b = αZZ, with α the "a" coefficient of the curve
+      b.mulCheckSparse(CoefA)       # b = αZZ, with α the "a" coefficient of the curve
 
       a += b
       a.div2()
@@ -516,8 +515,7 @@ func madd*[F; G: static Subgroup](
       a.square(HHH_or_Mpre, skipFinalSub = true)
       a *= HHH_or_Mpre              # a = 3X₁²
       b.square(Z1Z1)
-      # b.mulCheckSparse(CoefA)     # TODO: broken static compile-time type inference
-      b *= CoefA                    # b = αZZ, with α the "a" coefficient of the curve
+      b.mulCheckSparse(CoefA)       # b = αZZ, with α the "a" coefficient of the curve
 
       a += b
       a.div2()

diff --git a/constantine/math/extension_fields/towers.nim b/constantine/math/extension_fields/towers.nim
@@ -1440,11 +1440,11 @@ func mul_sparse_by_x0*(a: var QuadraticExt, sparseB: QuadraticExt) =
   a.mul_sparse_by_x0(a, sparseB)
 
 template mulCheckSparse*(a: var QuadraticExt, b: QuadraticExt) =
-  when b.isOne().bool:
+  when isOne(b).bool:
     discard
-  elif b.isMinusOne().bool:
+  elif isMinusOne(b).bool:
     a.neg()
-  elif b.c0.isZero().bool and b.c1.isOne().bool:
+  elif isZero(c0(b)).bool and isOne(c1(b)).bool:
     var t {.noInit.}: type(a.c0)
     when fromComplexExtension(b):
       t.neg(a.c1)
@@ -1454,7 +1454,7 @@ template mulCheckSparse*(a: var QuadraticExt, b: QuadraticExt) =
       t.prod(a.c1, NonResidue)
       a.c1 = a.c0
       a.c0 = t
-  elif b.c0.isZero().bool and b.c1.isMinusOne().bool:
+  elif isZero(c0(b)).bool and isMinusOne(c1(b)).bool:
     var t {.noInit.}: type(a.c0)
     when fromComplexExtension(b):
       t = a.c1
@@ -1464,9 +1464,9 @@ template mulCheckSparse*(a: var QuadraticExt, b: QuadraticExt) =
       t.prod(a.c1, NonResidue)
       a.c1.neg(a.c0)
       a.c0.neg(t)
-  elif b.c0.isZero().bool:
+  elif isZero(c0(b)).bool:
     a.mul_sparse_by_0y(b)
-  elif b.c1.isZero().bool:
+  elif isZero(c1(b)).bool:
     a.mul_sparse_by_x0(b)
   else:
     a *= b