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#86xkyvLFEupublic / public新しいバージョン

匿名作成日 5 days ago 失効まで 2 days 6.9 KB 構文: text

変更により、このペーストにリンクされた新しいペーストが作成されます — 元のペーストは変更されません。

新しいバージョン 変更により、このペーストにリンクされた新しいペーストが作成されます — 元のペーストは変更されません。

可視性パブリックフィードアクセス public

変更メモ (任意)

このペーストはパブリックフィードに表示されます。リンクを知っている人だけに見せたい場合は可視性を変更してください。

キャンセル

--- original_noise_math.h
+++ noise_math_optimized.h
@@ -1490,73 +1490,87 @@
     return f;
 }
 
+/* Unsigned arithmetic preserves the Java long wraparound. */
+static inline __attribute__((const, always_inline)) uint64_t
+noiseopt_biome_hash_step(uint64_t v, uint64_t salt) {
+    return v * (v * UINT64_C(6364136223846793005) +
+                UINT64_C(1442695040888963407)) + salt;
+}
+
+/* This comparison idiom maps to hardware MINPD for non-NaN inputs. */
+static inline __attribute__((const, always_inline)) double
+noiseopt_biome_min(double a, double b) {
+    return a > b ? b : a;
+}
+
 __attribute__((const)) uint32_t
 math_biome_access_sample(const int64_t theSeed, const int32_t x, const int32_t y, const int32_t z) {
-    const int32_t var0 = x - 2;
-    const int32_t var1 = y - 2;
-    const int32_t var2 = z - 2;
-    const int32_t var3 = var0 >> 2;
-    const int32_t var4 = var1 >> 2;
-    const int32_t var5 = var2 >> 2;
-    const double var6 = (double) (var0 & 3) / 4.0;
-    const double var7 = (double) (var1 & 3) / 4.0;
-    const double var8 = (double) (var2 & 3) / 4.0;
-    uint32_t var9 = 0;
-    double var10 = DBL_MAX;
+    /* Java integer subtraction wraps modulo 2^32. */
+    const int32_t xx = (int32_t)((uint32_t)x - 2u);
+    const int32_t yy = (int32_t)((uint32_t)y - 2u);
+    const int32_t zz = (int32_t)((uint32_t)z - 2u);
+
+    const int32_t cx = xx >> 2;
+    const int32_t cy = yy >> 2;
+    const int32_t cz = zz >> 2;
+    const double fx = (double)(xx & 3) * 0.25;
+    const double fy = (double)(yy & 3) * 0.25;
+    const double fz = (double)(zz & 3) * 0.25;
+
+    const uint64_t seed = (uint64_t)theSeed;
+    const uint64_t x0 = (uint64_t)(int64_t)cx;
+    const uint64_t x1 = (uint64_t)(int64_t)(cx + 1);
+    const uint64_t y0 = (uint64_t)(int64_t)cy;
+    const uint64_t y1 = (uint64_t)(int64_t)(cy + 1);
+    const uint64_t z0 = (uint64_t)(int64_t)cz;
+    const uint64_t z1 = (uint64_t)(int64_t)(cz + 1);
 
-    double var28s[8];
 
+
+    double distance[8];
 #pragma clang loop vectorize_width(NOISEOPT_DOUBLE_LANES) interleave_count(NOISEOPT_BIOME_INTERLEAVE)
-    for (uint32_t var11 = 0; var11 < 8; ++var11) {
-        uint32_t var12 = var11 & 4;
-        uint32_t var13 = var11 & 2;
-        uint32_t var14 = var11 & 1;
-        int64_t var15 = var12 ? var3 + 1 : var3;
-        int64_t var16 = var13 ? var4 + 1 : var4;
-        int64_t var17 = var14 ? var5 + 1 : var5;
-        double var18 = var12 ? var6 - 1.0 : var6;
-        double var19 = var13 ? var7 - 1.0 : var7;
-        double var20 = var14 ? var8 - 1.0 : var8;
-        int64_t var21 = theSeed * (theSeed * 6364136223846793005L + 1442695040888963407L) + var15;
-        var21 = var21 * (var21 * 6364136223846793005L + 1442695040888963407L) + var16;
-        var21 = var21 * (var21 * 6364136223846793005L + 1442695040888963407L) + var17;
-        var21 = var21 * (var21 * 6364136223846793005L + 1442695040888963407L) + var15;
-        var21 = var21 * (var21 * 6364136223846793005L + 1442695040888963407L) + var16;
-        var21 = var21 * (var21 * 6364136223846793005L + 1442695040888963407L) + var17;
-        double var22 = (double) ((var21 >> 24) & 1023) / 1024.0;
-        double var23 = (var22 - 0.5) * 0.9;
-        var21 = var21 * (var21 * 6364136223846793005L + 1442695040888963407L) + theSeed;
-        double var24 = (double) ((var21 >> 24) & 1023) / 1024.0;
-        double var25 = (var24 - 0.5) * 0.9;
-        var21 = var21 * (var21 * 6364136223846793005L + 1442695040888963407L) + theSeed;
-        double var26 = (double) ((var21 >> 24) & 1023) / 1024.0;
-        double var27 = (var26 - 0.5) * 0.9;
-        double var28 = math_square(var20 + var27) + math_square(var19 + var25) + math_square(var18 + var23);
-        __builtin_assume(!__builtin_isnan(var28) && !__builtin_signbit(var28));
-        var28s[var11] = var28;
+    for (uint32_t i = 0; i < 8; ++i) {
+        const uint64_t ix = (i & 4) ? x1 : x0;
+        const uint64_t iy = (i & 2) ? y1 : y0;
+        const uint64_t iz = (i & 1) ? z1 : z0;
+        const double dx = (i & 4) ? fx - 1.0 : fx;
+        const double dy = (i & 2) ? fy - 1.0 : fy;
+        const double dz = (i & 1) ? fz - 1.0 : fz;
+
+        uint64_t h = noiseopt_biome_hash_step(noiseopt_biome_hash_step(seed, ix), iy);
+        h = noiseopt_biome_hash_step(h, iz);
+        h = noiseopt_biome_hash_step(h, ix);
+        h = noiseopt_biome_hash_step(h, iy);
+        h = noiseopt_biome_hash_step(h, iz);
+
+        const double rx = ((double)((h >> 24) & 1023u) / 1024.0 - 0.5) * 0.9;
+        h = noiseopt_biome_hash_step(h, seed);
+        const double ry = ((double)((h >> 24) & 1023u) / 1024.0 - 0.5) * 0.9;
+        h = noiseopt_biome_hash_step(h, seed);
+        const double rz = ((double)((h >> 24) & 1023u) / 1024.0 - 0.5) * 0.9;
+
+        distance[i] = math_square(dz + rz) + math_square(dy + ry) + math_square(dx + rx);
     }
 
-    // use bmin or use >= produces different asm
-    double m04 = __builtin_fmin(var28s[0], var28s[4]);
-    double m15 = __builtin_fmin(var28s[1], var28s[5]);
-    double m26 = __builtin_fmin(var28s[2], var28s[6]);
-    double m37 = __builtin_fmin(var28s[3], var28s[7]);
-    double m0426 = __builtin_fmin(m04, m26);
-    double m1537 = __builtin_fmin(m15, m37);
-    double minimum = __builtin_fmin(m0426, m1537);
-
-    uint8_t bitmap = (uint8_t)(var28s[0] == minimum)
-               | (uint8_t)((var28s[1] == minimum) << 1)
-               | (uint8_t)((var28s[2] == minimum) << 2)
-               | (uint8_t)((var28s[3] == minimum) << 3)
-               | (uint8_t)((var28s[4] == minimum) << 4)
-               | (uint8_t)((var28s[5] == minimum) << 5)
-               | (uint8_t)((var28s[6] == minimum) << 6)
-               | (uint8_t)((var28s[7] == minimum) << 7);
- 
-    return __builtin_ctz(bitmap);
+    const double m04 = noiseopt_biome_min(distance[0], distance[4]);
+    const double m15 = noiseopt_biome_min(distance[1], distance[5]);
+    const double m26 = noiseopt_biome_min(distance[2], distance[6]);
+    const double m37 = noiseopt_biome_min(distance[3], distance[7]);
+    const double m0426 = noiseopt_biome_min(m04, m26);
+    const double m1537 = noiseopt_biome_min(m15, m37);
+    const double minimum = noiseopt_biome_min(m0426, m1537);
+
+    /* Distances are finite and >= +0.0, so at least one lane matches. */
+    const unsigned mask = ((unsigned)(distance[0] == minimum) << 0)
+                        | ((unsigned)(distance[1] == minimum) << 1)
+                        | ((unsigned)(distance[2] == minimum) << 2)
+                        | ((unsigned)(distance[3] == minimum) << 3)
+                        | ((unsigned)(distance[4] == minimum) << 4)
+                        | ((unsigned)(distance[5] == minimum) << 5)
+                        | ((unsigned)(distance[6] == minimum) << 6)
+                        | ((unsigned)(distance[7] == minimum) << 7);
+    return (uint32_t)__builtin_ctz(mask);
 }
-
 typedef const struct aquifer_data {
     int32_t startX;
     int32_t startY;