nir: add builtin builder

also move some of the GLSL builtins over we will need for implementing
some OpenCL builtins

v2: replace NIR_IMM_FP by nir_imm_floatN_t in ported code
    fix up changes caused by swizzle rework

Reviewed-by: Jason Ekstrand <[email protected]>
Signed-off-by: Karol Herbst <[email protected]>

1 files changed, 65 insertions, 0 deletions

diff --git a/src/compiler/nir/nir_builtin_builder.c b/src/compiler/nir/nir_builtin_builder.c
new file mode 100644
index 00000000000..252a7691f36
--- /dev/null
+++ b/src/compiler/nir/nir_builtin_builder.c
@@ -0,0 +1,65 @@
+/*
+ * Copyright © 2018 Red Hat Inc.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a
+ * copy of this software and associated documentation files (the "Software"),
+ * to deal in the Software without restriction, including without limitation
+ * the rights to use, copy, modify, merge, publish, distribute, sublicense,
+ * and/or sell copies of the Software, and to permit persons to whom the
+ * Software is furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice (including the next
+ * paragraph) shall be included in all copies or substantial portions of the
+ * Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
+ * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
+ * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
+ * IN THE SOFTWARE.
+ */
+
+#include "nir.h"
+#include "nir_builtin_builder.h"
+
+nir_ssa_def*
+nir_cross(nir_builder *b, nir_ssa_def *x, nir_ssa_def *y)
+{
+   unsigned yzx[3] = { 1, 2, 0 };
+   unsigned zxy[3] = { 2, 0, 1 };
+
+   return nir_fsub(b, nir_fmul(b, nir_swizzle(b, x, yzx, 3, true),
+                                  nir_swizzle(b, y, zxy, 3, true)),
+                      nir_fmul(b, nir_swizzle(b, x, zxy, 3, true),
+                                  nir_swizzle(b, y, yzx, 3, true)));
+}
+
+nir_ssa_def*
+nir_fast_length(nir_builder *b, nir_ssa_def *vec)
+{
+   switch (vec->num_components) {
+   case 1: return nir_fsqrt(b, nir_fmul(b, vec, vec));
+   case 2: return nir_fsqrt(b, nir_fdot2(b, vec, vec));
+   case 3: return nir_fsqrt(b, nir_fdot3(b, vec, vec));
+   case 4: return nir_fsqrt(b, nir_fdot4(b, vec, vec));
+   default:
+      unreachable("Invalid number of components");
+   }
+}
+
+nir_ssa_def*
+nir_smoothstep(nir_builder *b, nir_ssa_def *edge0, nir_ssa_def *edge1, nir_ssa_def *x)
+{
+   nir_ssa_def *f2 = nir_imm_floatN_t(b, 2.0, x->bit_size);
+   nir_ssa_def *f3 = nir_imm_floatN_t(b, 3.0, x->bit_size);
+
+   /* t = clamp((x - edge0) / (edge1 - edge0), 0, 1) */
+   nir_ssa_def *t =
+      nir_fsat(b, nir_fdiv(b, nir_fsub(b, x, edge0),
+                              nir_fsub(b, edge1, edge0)));
+
+   /* result = t * t * (3 - 2 * t) */
+   return nir_fmul(b, t, nir_fmul(b, t, nir_fsub(b, f3, nir_fmul(b, f2, t))));
+}