nir: passthrough-edgeflags support

Handled by tgsi_emulate for glsl->tgsi case.

Signed-off-by: Rob Clark <robclark@freedesktop.org>
Reviewed-by: Connor Abbott <cwabbott0@gmail.com>
Reviewed-by: Eric Anholt <eric@anholt.net>

src/compiler/Makefile.sources

@@ -200,6 +200,7 @@ NIR_FILES = \
 	nir/nir_lower_indirect_derefs.c \
 	nir/nir_lower_io.c \
 	nir/nir_lower_outputs_to_temporaries.c \
+	nir/nir_lower_passthrough_edgeflags.c \
 	nir/nir_lower_phis_to_scalar.c \
 	nir/nir_lower_returns.c \
 	nir/nir_lower_samplers.c \

src/compiler/nir/nir.h

@@ -2374,6 +2374,8 @@ void nir_lower_two_sided_color(nir_shader *shader);
 
 void nir_lower_clamp_color_outputs(nir_shader *shader);
 
+void nir_lower_passthrough_edgeflags(nir_shader *shader);
+
 typedef struct nir_lower_wpos_ytransform_options {
    int state_tokens[5];
    bool fs_coord_origin_upper_left :1;

src/compiler/nir/nir_lower_passthrough_edgeflags.c

@@ -0,0 +1,58 @@
+/*
+ * Copyright © 2015 Red Hat
+ *
+ * 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_builder.h"
+
+static void
+lower_impl(nir_function_impl *impl)
+{
+   nir_shader *shader = impl->function->shader;
+   nir_builder b;
+   nir_variable *in, *out;
+   nir_ssa_def *def;
+
+   nir_builder_init(&b, impl);
+   b.cursor = nir_before_cf_list(&impl->body);
+
+   in  = nir_variable_create(shader, nir_var_shader_in,
+                             glsl_vec4_type(), "edgeflag_in");
+   in->data.location = VERT_ATTRIB_EDGEFLAG;
+
+   out = nir_variable_create(shader, nir_var_shader_out,
+                             glsl_vec4_type(), "edgeflag_out");
+   out->data.location = VARYING_SLOT_EDGE;
+
+   def = nir_load_var(&b, in);
+   nir_store_var(&b, out, def, 0xf);
+
+   nir_metadata_preserve(impl, nir_metadata_block_index |
+                               nir_metadata_dominance);
+}
+
+void nir_lower_passthrough_edgeflags(nir_shader *shader)
+{
+   nir_function *function = nir_shader_get_entrypoint(shader);
+   if (function->impl)
+      lower_impl(function->impl);
+}