SPIRV-Tools/source/opt/passes.h
qining eb60e2945a Unify constants pass
De-duplicate constants and unifies the uses of constants for a SPIR-V
module. If two constants are defined exactly the same, only one of them
will be kept and all the uses of the removed constant will be redirected
to the kept one.

This pass handles normal constants (defined with
OpConstant{|True|False|Composite}), some spec constants (those defined
with OpSpecConstant{Op|Composite}) and null constants (defined with
OpConstantNull).

There are several cases not handled by this pass:

  1) If there are decorations for the result id of a constant defining
  instruction, that instruction will not be processed. This means the
  instruction won't be used to replace other instructions and other
  instructions won't be used to replace it either.

  2) This pass does not unify null constants (defined with
  OpConstantNull instruction) with their equivalent zero-valued normal
  constants (defined with OpConstant{|False|Composite} with zero as the
  operand values or component values).
2016-09-01 11:46:05 -04:00

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// Copyright (c) 2016 Google Inc.
//
// Permission is hereby granted, free of charge, to any person obtaining a
// copy of this software and/or associated documentation files (the
// "Materials"), to deal in the Materials without restriction, including
// without limitation the rights to use, copy, modify, merge, publish,
// distribute, sublicense, and/or sell copies of the Materials, and to
// permit persons to whom the Materials are furnished to do so, subject to
// the following conditions:
//
// The above copyright notice and this permission notice shall be included
// in all copies or substantial portions of the Materials.
//
// MODIFICATIONS TO THIS FILE MAY MEAN IT NO LONGER ACCURATELY REFLECTS
// KHRONOS STANDARDS. THE UNMODIFIED, NORMATIVE VERSIONS OF KHRONOS
// SPECIFICATIONS AND HEADER INFORMATION ARE LOCATED AT
// https://www.khronos.org/registry/
//
// THE MATERIALS ARE 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
// MATERIALS OR THE USE OR OTHER DEALINGS IN THE MATERIALS.
#ifndef LIBSPIRV_OPT_PASSES_H_
#define LIBSPIRV_OPT_PASSES_H_
// A single header to include all passes.
#include "eliminate_dead_constant_pass.h"
#include "fold_spec_constant_op_and_composite_pass.h"
#include "freeze_spec_constant_value_pass.h"
#include "null_pass.h"
#include "strip_debug_info_pass.h"
#include "unify_const_pass.h"
#endif // LIBSPIRV_OPT_PASSES_H_