glsl ubo/ssbo: Add lower_buffer_access class

This class has code that will be shared by lower_ubo_reference and
lower_shared_reference. (lower_shared_reference will be used to
support compute shader shared variables.)

v2:
 * Add lower_buffer_access.h to makefile (Emil)
 * Remove static is_dereferenced_thing_row_major from
   lower_buffer_access.cpp. This will become a lower_buffer_access
   method in the next commit.
 * Pass mem_ctx as parameter rather than using a member variable (Iago)

Signed-off-by: Jordan Justen <[email protected]>
Reviewed-by: Iago Toral Quiroga <[email protected]>
Reviewed-by: Kristian Høgsberg <[email protected]>

1 files changed, 58 insertions, 0 deletions

diff --git a/src/glsl/lower_buffer_access.h b/src/glsl/lower_buffer_access.h
new file mode 100644
index 00000000000..0ef6f47f4f0
--- /dev/null
+++ b/src/glsl/lower_buffer_access.h
@@ -0,0 +1,58 @@
+/*
+ * Copyright (c) 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.
+ */
+
+/**
+ * \file lower_buffer_access.h
+ *
+ * Helper for IR lowering pass to replace dereferences of buffer object based
+ * shader variables with intrinsic function calls.
+ *
+ * This helper is used by lowering passes for UBOs, SSBOs and compute shader
+ * shared variables.
+ */
+
+#pragma once
+#ifndef LOWER_BUFFER_ACCESS_H
+#define LOWER_BUFFER_ACCESS_H
+
+#include "ir.h"
+#include "ir_rvalue_visitor.h"
+
+namespace lower_buffer_access {
+
+class lower_buffer_access : public ir_rvalue_enter_visitor {
+public:
+   virtual void
+   insert_buffer_access(void *mem_ctx, ir_dereference *deref,
+                        const glsl_type *type, ir_rvalue *offset,
+                        unsigned mask, int channel) = 0;
+
+   void emit_access(void *mem_ctx, bool is_write, ir_dereference *deref,
+                    ir_variable *base_offset, unsigned int deref_offset,
+                    bool row_major, int matrix_columns,
+                    unsigned int packing, unsigned int write_mask);
+};
+
+} /* namespace lower_buffer_access */
+
+#endif /* LOWER_BUFFER_ACCESS_H */