diff options
Diffstat (limited to 'src/glsl')
| -rw-r--r-- | src/glsl/Makefile.sources | 1 | ||||
| -rw-r--r-- | src/glsl/ir_optimization.h | 1 | ||||
| -rw-r--r-- | src/glsl/lower_bounded_loops.cpp | 117 |
3 files changed, 119 insertions, 0 deletions
diff --git a/src/glsl/Makefile.sources b/src/glsl/Makefile.sources index 2e81deddabb..724c7b403ca 100644 --- a/src/glsl/Makefile.sources +++ b/src/glsl/Makefile.sources @@ -59,6 +59,7 @@ LIBGLSL_FILES = \ $(GLSL_SRCDIR)/loop_analysis.cpp \ $(GLSL_SRCDIR)/loop_controls.cpp \ $(GLSL_SRCDIR)/loop_unroll.cpp \ + $(GLSL_SRCDIR)/lower_bounded_loops.cpp \ $(GLSL_SRCDIR)/lower_clip_distance.cpp \ $(GLSL_SRCDIR)/lower_discard.cpp \ $(GLSL_SRCDIR)/lower_discard_flow.cpp \ diff --git a/src/glsl/ir_optimization.h b/src/glsl/ir_optimization.h index 3ca9f574453..87c2c820b3c 100644 --- a/src/glsl/ir_optimization.h +++ b/src/glsl/ir_optimization.h @@ -101,6 +101,7 @@ bool do_swizzle_swizzle(exec_list *instructions); bool do_tree_grafting(exec_list *instructions); bool do_vec_index_to_cond_assign(exec_list *instructions); bool do_vec_index_to_swizzle(exec_list *instructions); +bool lower_bounded_loops(exec_list *instructions); bool lower_discard(exec_list *instructions); void lower_discard_flow(exec_list *instructions); bool lower_instructions(exec_list *instructions, unsigned what_to_lower); diff --git a/src/glsl/lower_bounded_loops.cpp b/src/glsl/lower_bounded_loops.cpp new file mode 100644 index 00000000000..10f272f36f8 --- /dev/null +++ b/src/glsl/lower_bounded_loops.cpp @@ -0,0 +1,117 @@ +/* + * Copyright © 2013 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 + * + * This pass converts bounded loops (those whose ir_loop contains non-null + * values for \c from, \c to, \c increment, and \c counter) into unbounded + * loops. + * + * For instance: + * + * (loop (declare () uint i) (constant uint 0) (constant uint 4) + * (constant uint 1) + * ...loop body...) + * + * Is transformed into: + * + * (declare () uint i) + * (assign (x) (var_ref i) (constant uint 0)) + * (loop + * (if (expression bool >= (var_ref i) (constant uint 4)) + * (break) + * ()) + * ...loop body... + * (assign (x) (var_ref i) + * (expression uint + (var_ref i) (constant uint 1)))) + */ + +#include "ir_hierarchical_visitor.h" +#include "ir.h" +#include "ir_builder.h" + +using namespace ir_builder; + +namespace { + +class lower_bounded_loops_visitor : public ir_hierarchical_visitor { +public: + lower_bounded_loops_visitor() + : progress(false) + { + } + + virtual ir_visitor_status visit_leave(ir_loop *ir); + + bool progress; +}; + +} /* anonymous namespace */ + + +ir_visitor_status +lower_bounded_loops_visitor::visit_leave(ir_loop *ir) +{ + if (ir->counter == NULL) + return visit_continue; + + exec_list new_instructions; + ir_factory f(&new_instructions, ralloc_parent(ir)); + + /* Before the loop, declare the counter and initialize it to "from". */ + f.emit(ir->counter); + f.emit(assign(ir->counter, ir->from)); + ir->insert_before(&new_instructions); + + /* At the top of the loop, compare the counter to "to", and break if the + * comparison succeeds. + */ + ir_loop_jump *brk = new(f.mem_ctx) ir_loop_jump(ir_loop_jump::jump_break); + ir_expression_operation cmp = (ir_expression_operation) ir->cmp; + ir->body_instructions.push_head(if_tree(expr(cmp, ir->counter, ir->to), + brk)); + + /* At the bottom of the loop, increment the counter. */ + ir->body_instructions.push_tail(assign(ir->counter, + add(ir->counter, ir->increment))); + + /* NULL out the counter, from, to, and increment variables. */ + ir->counter = NULL; + ir->from = NULL; + ir->to = NULL; + ir->increment = NULL; + + this->progress = true; + return visit_continue; +} + + +bool +lower_bounded_loops(exec_list *instructions) +{ + lower_bounded_loops_visitor v; + + visit_list_elements(&v, instructions); + + return v.progress; +} |