feat(compiler): warn when there is overflow in simulation

zama-ai · Apr 4, 2024 · 5abf580 · 5abf580
1 parent e9dcc20
commit 5abf580
Showing 1 changed file with 12 additions and 2 deletions.
diff --git a/compilers/concrete-compiler/compiler/lib/Runtime/simulation.cpp b/compilers/concrete-compiler/compiler/lib/Runtime/simulation.cpp
@@ -183,9 +183,19 @@ void sim_wop_pbs_crt(
 
 uint64_t sim_neg_lwe_u64(uint64_t plaintext) { return ~plaintext + 1; }
 
-uint64_t sim_add_lwe_u64(uint64_t lhs, uint64_t rhs) { return lhs + rhs; }
+uint64_t sim_add_lwe_u64(uint64_t lhs, uint64_t rhs) {
+  if (lhs > UINT64_MAX - rhs) {
+    printf("WARNING: overflow happened during addition in simulation\n");
+  }
+  return lhs + rhs;
+}
 
-uint64_t sim_mul_lwe_u64(uint64_t lhs, uint64_t rhs) { return lhs * rhs; }
+uint64_t sim_mul_lwe_u64(uint64_t lhs, uint64_t rhs) {
+  if (rhs != 0 && lhs > UINT64_MAX / rhs) {
+    printf("WARNING: overflow happened during multiplication in simulation\n");
+  }
+  return lhs * rhs;
+}
 
 void sim_encode_expand_lut_for_boostrap(
     uint64_t *out_allocated, uint64_t *out_aligned, uint64_t out_offset,