fix *= etc bugs in C++ wrapper

include/decaf.hxx

@@ -163,22 +163,22 @@ public:
     }
     
     /** Add. */
-    inline Scalar operator+ (const Scalar &q) const NOEXCEPT { Scalar r; decaf_448_scalar_add(r.s,s,q.s); return r; }
+    inline Scalar  operator+ (const Scalar &q) const NOEXCEPT { Scalar r; decaf_448_scalar_add(r.s,s,q.s); return r; }
     
     /** Add to this. */
-    inline Scalar operator+=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_add(s,s,q.s); return *this; }
+    inline Scalar &operator+=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_add(s,s,q.s); return *this; }
     
     /** Subtract. */
-    inline Scalar operator- (const Scalar &q) const NOEXCEPT { Scalar r; decaf_448_scalar_sub(r.s,s,q.s); return r; }
+    inline Scalar  operator- (const Scalar &q) const NOEXCEPT { Scalar r; decaf_448_scalar_sub(r.s,s,q.s); return r; }
     
     /** Subtract from this. */
-    inline Scalar operator-=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_sub(s,s,q.s); return *this; }
+    inline Scalar &operator-=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_sub(s,s,q.s); return *this; }
     
     /** Multiply */
-    inline Scalar operator* (const Scalar &q) const NOEXCEPT { Scalar r; decaf_448_scalar_mul(r.s,s,q.s); return r; }
+    inline Scalar  operator* (const Scalar &q) const NOEXCEPT { Scalar r; decaf_448_scalar_mul(r.s,s,q.s); return r; }
     
     /** Multiply into this. */
-    inline Scalar operator*=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_mul(s,s,q.s); return *this; }
+    inline Scalar &operator*=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_mul(s,s,q.s); return *this; }
     
     /** Negate */
     inline Scalar operator- ()                const NOEXCEPT { Scalar r; decaf_448_scalar_sub(r.s,decaf_448_scalar_zero,s); return r; }
@@ -190,7 +190,7 @@ public:
     inline Scalar operator/ (const Scalar &q) const NOEXCEPT { Scalar r; decaf_448_scalar_mul(r.s,s,q.inverse().s); return r; }
     
     /** @brief Divide by inverting q. If q == 0, return 0.  */
-    inline Scalar operator/=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_mul(s,s,q.inverse().s); return *this; }
+    inline Scalar &operator/=(const Scalar &q)       NOEXCEPT { decaf_448_scalar_mul(s,s,q.inverse().s); return *this; }
     
     /** @brief Compare in constant time */
     inline bool   operator!=(const Scalar &q) const NOEXCEPT { return ! decaf_448_scalar_eq(s,q.s); }
@@ -333,22 +333,22 @@ public:
     }
     
     /** @brief Point add. */
-    inline Point operator+ (const Point &q)  const NOEXCEPT { Point r; decaf_448_point_add(r.p,p,q.p); return r; }
+    inline Point  operator+ (const Point &q)  const NOEXCEPT { Point r; decaf_448_point_add(r.p,p,q.p); return r; }
     
     /** @brief Point add. */
-    inline Point operator+=(const Point &q)        NOEXCEPT { decaf_448_point_add(p,p,q.p); return *this; }
+    inline Point &operator+=(const Point &q)        NOEXCEPT { decaf_448_point_add(p,p,q.p); return *this; }
     
     /** @brief Point subtract. */
-    inline Point operator- (const Point &q)  const NOEXCEPT { Point r; decaf_448_point_sub(r.p,p,q.p); return r; }
+    inline Point  operator- (const Point &q)  const NOEXCEPT { Point r; decaf_448_point_sub(r.p,p,q.p); return r; }
     
     /** @brief Point subtract. */
-    inline Point operator-=(const Point &q)        NOEXCEPT { decaf_448_point_sub(p,p,q.p); return *this; }
+    inline Point &operator-=(const Point &q)        NOEXCEPT { decaf_448_point_sub(p,p,q.p); return *this; }
     
     /** @brief Point negate. */
-    inline Point operator- ()                const NOEXCEPT { Point r; decaf_448_point_negate(r.p,p); return r; }
+    inline Point  operator- ()                const NOEXCEPT { Point r; decaf_448_point_negate(r.p,p); return r; }
     
     /** @brief Double the point out of place. */
-    inline Point times_two ()                const NOEXCEPT { Point r; decaf_448_point_double(r.p,p); return r; }
+    inline Point  times_two ()                const NOEXCEPT { Point r; decaf_448_point_double(r.p,p); return r; }
     
     /** @brief Double the point in place. */
     inline Point &double_in_place()                NOEXCEPT { decaf_448_point_double(p,p); return *this; }
@@ -360,13 +360,16 @@ public:
     inline bool  operator==(const Point &q)  const NOEXCEPT { return !!decaf_448_point_eq(p,q.p); }
     
     /** @brief Scalar multiply. */
-    inline Point operator* (const Scalar &s) const NOEXCEPT { Point r; decaf_448_point_scalarmul(r.p,p,s.s); return r; }
+    inline Point  operator* (const Scalar &s) const NOEXCEPT { Point r; decaf_448_point_scalarmul(r.p,p,s.s); return r; }
     
     /** @brief Scalar multiply in place. */
-    inline Point operator*=(const Scalar &s)       NOEXCEPT { decaf_448_point_scalarmul(p,p,s.s); return *this; }
+    inline Point &operator*=(const Scalar &s)       NOEXCEPT { decaf_448_point_scalarmul(p,p,s.s); return *this; }
     
     /** @brief Multiply by s.inverse().  If s=0, maps to the identity. */
-    inline Point operator/ (const Scalar &s) const NOEXCEPT { return (*this) * s.inverse(); }
+    inline Point  operator/ (const Scalar &s) const NOEXCEPT { return (*this) * s.inverse(); }
+    
+    /** @brief Multiply by s.inverse().  If s=0, maps to the identity. */
+    inline Point &operator/=(const Scalar &s)       NOEXCEPT { return (*this) *= s.inverse(); }
     
     /** @brief Double-scalar multiply, equivalent to q*qs + r*rs but faster. */
     static inline Point double_scalarmul (

src/decaf_fast.c

@@ -661,12 +661,14 @@ void decaf_bzero (
 #ifdef __STDC_LIB_EXT1__
     memset_s(s, size, 0, size);
 #else
-    /* PERF: word at a time? */
+    const size_t sw = sizeof(decaf_word_t);
     volatile uint8_t *destroy = (volatile uint8_t *)s;
-    unsigned i;
-    for (i=0; i<size; i++) {
-        destroy[i] = 0;
-    }
+    for (; size && ((decaf_word_t)destroy)%sw; size--, destroy++)
+        *destroy = 0;
+    for (; size >= sw; size -= sw, destroy += sw)
+        *(volatile decaf_word_t *)destroy = 0;
+    for (; size; size--, destroy++)
+        *destroy = 0;
 #endif
 }
 

test/bench_decaf.cxx

@@ -134,14 +134,15 @@ int main(int argc, char **argv) {
         std::string ep;
         
         printf("Micro-benchmarks:\n");
-        for (Benchmark b("Scalar add", 1000); b.iter(); ) { s+t; }
-        for (Benchmark b("Scalar times", 100); b.iter(); ) { s*t; }
+        for (Benchmark b("Scalar add", 1000); b.iter(); ) { s+=t; }
+        for (Benchmark b("Scalar times", 100); b.iter(); ) { s*=t; }
         for (Benchmark b("Scalar inv", 10); b.iter(); ) { s.inverse(); }
-        for (Benchmark b("Point add", 100); b.iter(); ) { p + q; }
+        for (Benchmark b("Point add", 100); b.iter(); ) { p += q; }
         for (Benchmark b("Point double", 100); b.iter(); ) { p.double_in_place(); }
         for (Benchmark b("Point scalarmul"); b.iter(); ) { p * s; }
         for (Benchmark b("Point encode"); b.iter(); ) { ep = std::string(p); }
         for (Benchmark b("Point decode"); b.iter(); ) { p = Point(ep); }
+        for (Benchmark b("Point create/destroy"); b.iter(); ) { Point r; }
         for (Benchmark b("Point hash nonuniform"); b.iter(); ) { Point::from_hash(ep); }
         for (Benchmark b("Point hash uniform"); b.iter(); ) { Point::from_hash(ep+ep); }
         for (Benchmark b("Point double scalarmul"); b.iter(); ) { Point::double_scalarmul(p,s,q,t); }