msm/pippenger.cuh: clear scalar's msb with abs() method.

This helps Pasta curves, which have sparse moduli.
supranational · Feb 20, 2024 · 2a43112 · 2a43112
1 parent a7766e4
commit 2a43112
Showing 1 changed file with 1 addition and 2 deletions.
diff --git a/msm/pippenger.cuh b/msm/pippenger.cuh
@@ -98,8 +98,7 @@ void breakdown(vec2d_t<uint32_t> digits, const scalar_t scalars[], size_t len,
 #endif
 
         // clear the most significant bit
-        uint32_t msb = s[top_i] >> ((scalar_t::nbits - 1) % 32);
-        s.cneg(msb);
+        uint32_t msb = s.abs();
         msb <<= 31;
 
         scalar = s;