src/world: cleanup & fix hash stuff

2 files changed, 41 insertions, 23 deletions

diff --git a/compat/int-hash.cpp b/compat/int-hash.cpp
new file mode 100644
index 00000000..ae2e6729
--- /dev/null
+++ b/compat/int-hash.cpp
@@ -0,0 +1,37 @@
+#include "int-hash.hpp"
+#include <bit>
+
+namespace floormat {
+
+size_t int_hash32(uint32_t x) noexcept
+{
+    if constexpr(sizeof(size_t) == 4)
+    {
+        // by Chris Wellons <https://nullprogram.com/blog/2018/07/31/>
+
+        x ^= x >> 15;
+        x *= 0x2c1b3c6dU;
+        x ^= x >> 12;
+        x *= 0x297a2d39U;
+        x ^= x >> 15;
+
+        return x;
+    }
+    else
+        return int_hash64(x);
+}
+
+size_t int_hash64(uint64_t x) noexcept
+{
+    // NASAM by Pelle Evensen <https://mostlymangling.blogspot.com/2020/01/nasam-not-another-strange-acronym-mixer.html>
+
+    x ^= std::rotr(x, 25) ^ std::rotr(x, 47);
+    x *= 0x9E6C63D0676A9A99UL;
+    x ^= x >> 23 ^ x >> 51;
+    x *= 0x9E6D62D06F6A9A9BUL;
+    x ^= x >> 23 ^ x >> 51;
+
+    return x;
+}
+
+} // namespace floormat
diff --git a/compat/int-hash.hpp b/compat/int-hash.hpp
index 52b4c170..e5cfc67a 100644
--- a/compat/int-hash.hpp
+++ b/compat/int-hash.hpp
@@ -1,30 +1,11 @@
 #pragma once
-#include <bit>
 
 namespace floormat {
 
-constexpr inline size_t int_hash(size_t x) noexcept
-{
-    if constexpr(sizeof(size_t) == 4)
-    {
-        // by Chris Wellons <https://nullprogram.com/blog/2018/07/31/>
-        x ^= x >> 15;
-        x *= 0x2c1b3c6dU;
-        x ^= x >> 12;
-        x *= 0x297a2d39U;
-        x ^= x >> 15;
-    }
-    else if constexpr(sizeof(size_t) == 8)
-    {
-        // NASAM by Pelle Evensen <https://mostlymangling.blogspot.com/2020/01/nasam-not-another-strange-acronym-mixer.html>
-        x ^= std::rotr(x, 25) ^ std::rotr(x, 47);
-        x *= 0x9E6C63D0676A9A99UL;
-        x ^= x >> 23 ^ x >> 51;
-        x *= 0x9E6D62D06F6A9A9BUL;
-        x ^= x >> 23 ^ x >> 51;
-    }
+size_t int_hash32(uint32_t x) noexcept;
+size_t int_hash64(uint64_t x) noexcept;
 
-    return x;
-}
+inline size_t int_hash(uint32_t x) noexcept { return int_hash32(x); }
+inline size_t int_hash(uint64_t x) noexcept { return int_hash64(x); }
 
 } // namespace floormat