diff options
Diffstat (limited to 'src/glsl/ir_explog_to_explog2.cpp')
-rw-r--r-- | src/glsl/ir_explog_to_explog2.cpp | 85 |
1 files changed, 85 insertions, 0 deletions
diff --git a/src/glsl/ir_explog_to_explog2.cpp b/src/glsl/ir_explog_to_explog2.cpp new file mode 100644 index 00000000000..4fe1daaee91 --- /dev/null +++ b/src/glsl/ir_explog_to_explog2.cpp @@ -0,0 +1,85 @@ +/* + * Copyright © 2010 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 ir_explog_to_explog2.cpp + * + * Many GPUs don't have a base e log or exponent instruction, but they + * do have base 2 versions, so this pass converts exp and log to exp2 + * and log2 operations. + */ + +#include <math.h> +#include "ir.h" +#include "glsl_types.h" + +class ir_explog_to_explog2_visitor : public ir_hierarchical_visitor { +public: + ir_explog_to_explog2_visitor() + { + this->progress = false; + } + + ir_visitor_status visit_leave(ir_expression *); + + bool progress; +}; + +bool +do_explog_to_explog2(exec_list *instructions) +{ + ir_explog_to_explog2_visitor v; + + visit_list_elements(&v, instructions); + return v.progress; +} + +ir_visitor_status +ir_explog_to_explog2_visitor::visit_leave(ir_expression *ir) +{ + if (ir->operation == ir_unop_exp) { + void *mem_ctx = talloc_parent(ir); + ir_constant *log2_e = new(mem_ctx) ir_constant(log2f(M_E)); + + ir->operation = ir_unop_exp2; + ir->operands[0] = new(mem_ctx) ir_expression(ir_binop_mul, + ir->operands[0]->type, + ir->operands[0], + log2_e); + this->progress = true; + } + + if (ir->operation == ir_unop_log) { + void *mem_ctx = talloc_parent(ir); + + ir->operation = ir_binop_mul; + ir->operands[0] = new(mem_ctx) ir_expression(ir_unop_log2, + ir->operands[0]->type, + ir->operands[0], + NULL); + ir->operands[1] = new(mem_ctx) ir_constant(1.0f / log2f(M_E)); + this->progress = true; + } + + return visit_continue; +} |