ObfusString: Fix consteval failure for excessively large strings

calamity-inc · Jan 20, 2025 · e1df30d · e1df30d
1 parent f41fcda
commit e1df30d
Showing 1 changed file with 19 additions and 13 deletions.
diff --git a/soup/ObfusString.hpp b/soup/ObfusString.hpp
@@ -43,12 +43,21 @@ NAMESPACE_SOUP
 			seed = rand.getConstexprSeed(Len);
 			LcgRng rng(seed);
 
-			// rot13
+			// copy input & apply rot13
 			for (size_t i = 0; i != Len; ++i)
 			{
 				m_data[i] = string::rot13(in[i]);
 			}
 
+			if (Len < 40'000)
+			{
+				// mirror
+				for (size_t i = 0, j = Len - 1; i != Len / 2; ++i, --j)
+				{
+					std::swap(m_data[i], m_data[j]);
+				}
+			}
+
 			// flip bits
 			for (size_t i = 0; i != Len; ++i)
 			{
@@ -59,12 +68,6 @@ NAMESPACE_SOUP
 				}
 				m_data[i] ^= rng.state >> (m * 8);
 			}
-
-			// mirror
-			for (size_t i = 0, j = Len - 1; i != Len / 2; ++i, --j)
-			{
-				std::swap(m_data[i], m_data[j]);
-			}
 		}
 
 		SOUP_NOINLINE void runtime_access() noexcept
@@ -76,12 +79,6 @@ NAMESPACE_SOUP
 			LcgRng rng(seed);
 			seed = 0;
 
-			// mirror
-			for (size_t i = 0, j = Len - 1; i != Len / 2; ++i, --j)
-			{
-				std::swap(m_data[i], m_data[j]);
-			}
-
 			// flip bits
 			for (size_t i = 0; i != Len; ++i)
 			{
@@ -93,6 +90,15 @@ NAMESPACE_SOUP
 				m_data[i] ^= rng.state >> (m * 8);
 			}
 
+			if constexpr (Len < 40'000)
+			{
+				// mirror
+				for (size_t i = 0, j = Len - 1; i != Len / 2; ++i, --j)
+				{
+					std::swap(m_data[i], m_data[j]);
+				}
+			}
+
 			// rot13
 			for (size_t i = 0; i != Len; ++i)
 			{