1 files changed, 75 insertions, 2 deletions
diff --git a/src/compiler/glsl/int64.glsl b/src/compiler/glsl/int64.glsl
index a2bec011e3e..84e80ee349b 100644
--- a/src/compiler/glsl/int64.glsl
+++ b/src/compiler/glsl/int64.glsl
@@ -4,8 +4,9 @@
  *
  * Using version 1.40+ prevents built-in variables from being included.
  */
-#version 140
-#extension GL_MESA_shader_integer_functions: require
+#version 400
+#extension GL_ARB_gpu_shader_int64: require
+#extension GL_ARB_shading_language_420pack: require
 
 uvec2
 umul64(uvec2 a, uvec2 b)
@@ -28,3 +29,75 @@ sign64(ivec2 a)
 
    return result;
 }
+
+uvec4
+udivmod64(uvec2 n, uvec2 d)
+{
+   uvec2 quot = uvec2(0U, 0U);
+   int log2_denom = findMSB(d.y) + 32;
+
+   /* If the upper 32 bits of denom are non-zero, it is impossible for shifts
+    * greater than 32 bits to occur.  If the upper 32 bits of the numerator
+    * are zero, it is impossible for (denom << [63, 32]) <= numer unless
+    * denom == 0.
+    */
+   if (d.y == 0 && n.y >= d.x) {
+      log2_denom = findMSB(d.x);
+
+      /* Since the upper 32 bits of denom are zero, log2_denom <= 31 and we
+       * don't have to compare log2_denom inside the loop as is done in the
+       * general case (below).
+       */
+      for (int i = 31; i >= 1; i--) {
+	 if (log2_denom <= 31 - i && (d.x << i) <= n.y) {
+	    n.y -= d.x << i;
+	    quot.y |= 1U << i;
+	 }
+      }
+
+      /* log2_denom is always <= 31, so manually peel the last loop
+       * iteration.
+       */
+      if (d.x <= n.y) {
+	 n.y -= d.x;
+	 quot.y |= 1U;
+      }
+   }
+
+   uint64_t d64 = packUint2x32(d);
+   uint64_t n64 = packUint2x32(n);
+   for (int i = 31; i >= 1; i--) {
+      if (log2_denom <= 63 - i && (d64 << i) <= n64) {
+	 n64 -= d64 << i;
+	 quot.x |= 1U << i;
+      }
+   }
+
+   /* log2_denom is always <= 63, so manually peel the last loop
+    * iteration.
+    */
+   if (d64 <= n64) {
+      n64 -= d64;
+      quot.x |= 1U;
+   }
+
+   return uvec4(quot, unpackUint2x32(n64));
+}
+
+uvec2
+udiv64(uvec2 n, uvec2 d)
+{
+   return udivmod64(n, d).xy;
+}
+
+ivec2
+idiv64(ivec2 _n, ivec2 _d)
+{
+   const bool negate = (_n.y < 0) != (_d.y < 0);
+   uvec2 n = unpackUint2x32(uint64_t(abs(packInt2x32(_n))));
+   uvec2 d = unpackUint2x32(uint64_t(abs(packInt2x32(_d))));
+
+   uvec2 quot = udivmod64(n, d).xy;
+
+   return negate ? unpackInt2x32(-int64_t(packUint2x32(quot))) : ivec2(quot);
+}