[Mesa-dev] [PATCH 15/23] i965: Revisit GLSL IR atomic counter intrinsic translation.

[Francisco Jerez]

This is a rewrite of the GLSL IR atomic counter intrinsics translation
code based on the recently introduced surface builder.  The new
implementation is considerably cleaner and back-end-independent.
---
 src/mesa/drivers/dri/i965/Makefile.sources         |   1 +
 src/mesa/drivers/dri/i965/brw_ir_glsl_intrinsics.h | 100 +++++++++++++++++++++
 2 files changed, 101 insertions(+)
 create mode 100644 src/mesa/drivers/dri/i965/brw_ir_glsl_intrinsics.h

diff --git a/src/mesa/drivers/dri/i965/Makefile.sources b/src/mesa/drivers/dri/i965/Makefile.sources
index 4e8b25c..fd6d840 100644
--- a/src/mesa/drivers/dri/i965/Makefile.sources
+++ b/src/mesa/drivers/dri/i965/Makefile.sources
@@ -67,6 +67,7 @@ i965_FILES = \
 	brw_interpolation_map.c \
 	brw_ir_allocator.h \
 	brw_ir_fs.h \
+	brw_ir_glsl_intrinsics.h \
 	brw_ir_surface_builder.h \
 	brw_ir_svec4.h \
 	brw_ir_vec4.h \
diff --git a/src/mesa/drivers/dri/i965/brw_ir_glsl_intrinsics.h b/src/mesa/drivers/dri/i965/brw_ir_glsl_intrinsics.h
new file mode 100644
index 0000000..cc838e9
--- /dev/null
+++ b/src/mesa/drivers/dri/i965/brw_ir_glsl_intrinsics.h
@@ -0,0 +1,100 @@
+/* -*- c++ -*- */
+/*
+ * Copyright © 2013-2015 Intel Corporation
+ *
+ * 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.
+ */
+
+#ifndef BRW_IR_GLSL_INTRINSICS_H
+#define BRW_IR_GLSL_INTRINSICS_H
+
+#include "brw_ir_surface_builder.h"
+#include "main/shaderimage.h"
+
+namespace brw {
+   namespace detail {
+      /**
+       * Process the i-th parameter passed to an intrinsic call.
+       */
+      template<typename S, typename V>
+      S
+      visit_argument(V *v, ir_call *ir, unsigned i)
+      {
+         unsigned j = 0;
+
+         foreach_in_list(ir_dereference, arg, &ir->actual_parameters) {
+            if (j++ == i) {
+               const unsigned n =
+                  (arg->type->is_scalar() || arg->type->is_vector() ||
+                   arg->type->is_matrix() ? arg->type->vector_elements : 4);
+               return src_vector(v->visit_result(arg), n);
+            }
+         }
+
+         return S();
+      }
+   }
+
+   /**
+    * Entry point for translating GLSL IR atomic counter intrinsics.
+    */
+   template<typename V, typename B>
+   void
+   visit_atomic_counter_intrinsic(V *v, const B &bld, ir_call *ir)
+   {
+      using namespace detail;
+      using namespace surface_access;
+      typedef typename B::vector_builder::src_reg src_reg;
+      typedef typename B::vector_builder::dst_reg dst_reg;
+      typename B::vector_builder vbld = bld.vector();
+
+      /* Get the referenced atomic counter variable. */
+      const ir_variable *var = static_cast<ir_dereference *>(
+         ir->actual_parameters.get_head())->variable_referenced();
+
+      /* Visit the arguments of the atomic intrinsic. */
+      const src_reg offset = visit_argument<src_reg>(v, ir, 0);
+      const src_reg surface(v->stage_prog_data->binding_table.abo_start +
+                            var->data.binding);
+
+      /* Get some metadata from the atomic intrinsic. */
+      const char *callee = ir->callee->function_name();
+      const unsigned rsize = (ir->return_deref ? 1 : 0);
+      src_reg tmp;
+
+      /* Emit a surface read or atomic op. */
+      if (!strcmp("__intrinsic_atomic_read", callee))
+         tmp = emit_untyped_read(vbld, surface, offset, 1, 1);
+
+      else if (!strcmp("__intrinsic_atomic_increment", callee))
+         tmp = emit_untyped_atomic(vbld, surface, offset, src_reg(), src_reg(),
+                                   1, rsize, BRW_AOP_INC);
+
+      else if (!strcmp("__intrinsic_atomic_predecrement", callee))
+         tmp = emit_untyped_atomic(vbld, surface, offset, src_reg(), src_reg(),
+                                   1, rsize, BRW_AOP_PREDEC);
+
+      /* Assign the result. */
+      if (ir->return_deref)
+         vbld.MOV(dst_reg(v->visit_result(ir->return_deref)), tmp);
+   }
+}
+
+#endif
-- 
2.3.5