xserver and mesa git update 28-12-2010

1 files changed, 0 insertions, 544 deletions

diff --git a/mesalib/src/glsl/ir_lower_jumps.cpp b/mesalib/src/glsl/ir_lower_jumps.cpp
deleted file mode 100644
index b69cc1ec3..000000000
--- a/mesalib/src/glsl/ir_lower_jumps.cpp
+++ /dev/null
@@ -1,544 +0,0 @@
-/*
- * Copyright © 2010 Luca Barbieri
- *
- * 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_lower_jumps.cpp
- */
-
-#include "glsl_types.h"
-#include <string.h>
-#include "ir.h"
-
-enum jump_strength
-{
-   strength_none,
-   strength_always_clears_execute_flag,
-   strength_continue,
-   strength_break,
-   strength_return,
-   strength_discard
-};
-
-struct block_record
-{
-   /* minimum jump strength (of lowered IR, not pre-lowering IR)
-    *
-    * If the block ends with a jump, must be the strength of the jump.
-    * Otherwise, the jump would be dead and have been deleted before)
-    *
-    * If the block doesn't end with a jump, it can be different than strength_none if all paths before it lead to some jump
-    * (e.g. an if with a return in one branch, and a break in the other, while not lowering them)
-    * Note that identical jumps are usually unified though.
-    */
-   jump_strength min_strength;
-
-   /* can anything clear the execute flag? */
-   bool may_clear_execute_flag;
-
-   block_record()
-   {
-      this->min_strength = strength_none;
-      this->may_clear_execute_flag = false;
-   }
-};
-
-struct loop_record
-{
-   ir_function_signature* signature;
-   ir_loop* loop;
-
-   /* used to avoid lowering the break used to represent lowered breaks */
-   unsigned nesting_depth;
-   bool in_if_at_the_end_of_the_loop;
-
-   bool may_set_return_flag;
-
-   ir_variable* break_flag;
-   ir_variable* execute_flag; /* cleared to emulate continue */
-
-   loop_record(ir_function_signature* p_signature = 0, ir_loop* p_loop = 0)
-   {
-      this->signature = p_signature;
-      this->loop = p_loop;
-      this->nesting_depth = 0;
-      this->in_if_at_the_end_of_the_loop = false;
-      this->may_set_return_flag = false;
-      this->break_flag = 0;
-      this->execute_flag = 0;
-   }
-
-   ir_variable* get_execute_flag()
-   {
-      /* also supported for the "function loop" */
-      if(!this->execute_flag) {
-         exec_list& list = this->loop ? this->loop->body_instructions : signature->body;
-         this->execute_flag = new(this->signature) ir_variable(glsl_type::bool_type, "execute_flag", ir_var_temporary);
-         list.push_head(new(this->signature) ir_assignment(new(this->signature) ir_dereference_variable(execute_flag), new(this->signature) ir_constant(true), 0));
-         list.push_head(this->execute_flag);
-      }
-      return this->execute_flag;
-   }
-
-   ir_variable* get_break_flag()
-   {
-      assert(this->loop);
-      if(!this->break_flag) {
-         this->break_flag = new(this->signature) ir_variable(glsl_type::bool_type, "break_flag", ir_var_temporary);
-         this->loop->insert_before(this->break_flag);
-         this->loop->insert_before(new(this->signature) ir_assignment(new(this->signature) ir_dereference_variable(break_flag), new(this->signature) ir_constant(false), 0));
-      }
-      return this->break_flag;
-   }
-};
-
-struct function_record
-{
-   ir_function_signature* signature;
-   ir_variable* return_flag; /* used to break out of all loops and then jump to the return instruction */
-   ir_variable* return_value;
-   bool is_main;
-   unsigned nesting_depth;
-
-   function_record(ir_function_signature* p_signature = 0)
-   {
-      this->signature = p_signature;
-      this->return_flag = 0;
-      this->return_value = 0;
-      this->nesting_depth = 0;
-      this->is_main = this->signature && (strcmp(this->signature->function_name(), "main") == 0);
-   }
-
-   ir_variable* get_return_flag()
-   {
-      if(!this->return_flag) {
-         this->return_flag = new(this->signature) ir_variable(glsl_type::bool_type, "return_flag", ir_var_temporary);
-         this->signature->body.push_head(new(this->signature) ir_assignment(new(this->signature) ir_dereference_variable(return_flag), new(this->signature) ir_constant(false), 0));
-         this->signature->body.push_head(this->return_flag);
-      }
-      return this->return_flag;
-   }
-
-   ir_variable* get_return_value()
-   {
-      if(!this->return_value) {
-         assert(!this->signature->return_type->is_void());
-         return_value = new(this->signature) ir_variable(this->signature->return_type, "return_value", ir_var_temporary);
-         this->signature->body.push_head(this->return_value);
-      }
-      return this->return_value;
-   }
-};
-
-struct ir_lower_jumps_visitor : public ir_control_flow_visitor {
-   bool progress;
-
-   struct function_record function;
-   struct loop_record loop;
-   struct block_record block;
-
-   bool pull_out_jumps;
-   bool lower_continue;
-   bool lower_break;
-   bool lower_sub_return;
-   bool lower_main_return;
-
-   ir_lower_jumps_visitor()
-   {
-      this->progress = false;
-   }
-
-   void truncate_after_instruction(exec_node *ir)
-   {
-      if (!ir)
-         return;
-
-      while (!ir->get_next()->is_tail_sentinel()) {
-         ((ir_instruction *)ir->get_next())->remove();
-         this->progress = true;
-      }
-   }
-
-   void move_outer_block_inside(ir_instruction *ir, exec_list *inner_block)
-   {
-      while (!ir->get_next()->is_tail_sentinel()) {
-         ir_instruction *move_ir = (ir_instruction *)ir->get_next();
-
-         move_ir->remove();
-         inner_block->push_tail(move_ir);
-      }
-   }
-
-   virtual void visit(class ir_loop_jump * ir)
-   {
-      truncate_after_instruction(ir);
-      this->block.min_strength = ir->is_break() ? strength_break : strength_continue;
-   }
-
-   virtual void visit(class ir_return * ir)
-   {
-      truncate_after_instruction(ir);
-      this->block.min_strength = strength_return;
-   }
-
-   virtual void visit(class ir_discard * ir)
-   {
-      truncate_after_instruction(ir);
-      this->block.min_strength = strength_discard;
-   }
-
-   enum jump_strength get_jump_strength(ir_instruction* ir)
-   {
-      if(!ir)
-         return strength_none;
-      else if(ir->ir_type == ir_type_loop_jump) {
-         if(((ir_loop_jump*)ir)->is_break())
-            return strength_break;
-         else
-            return strength_continue;
-      } else if(ir->ir_type == ir_type_return)
-         return strength_return;
-      else if(ir->ir_type == ir_type_discard)
-         return strength_discard;
-      else
-         return strength_none;
-   }
-
-   bool should_lower_jump(ir_jump* ir)
-   {
-      unsigned strength = get_jump_strength(ir);
-      bool lower;
-      switch(strength)
-      {
-      case strength_none:
-         lower = false; /* don't change this, code relies on it */
-         break;
-      case strength_continue:
-         lower = lower_continue;
-         break;
-      case strength_break:
-         assert(this->loop.loop);
-         /* never lower "canonical break" */
-         if(ir->get_next()->is_tail_sentinel() && (this->loop.nesting_depth == 0
-               || (this->loop.nesting_depth == 1 && this->loop.in_if_at_the_end_of_the_loop)))
-            lower = false;
-         else
-            lower = lower_break;
-         break;
-      case strength_return:
-         /* never lower return at the end of a this->function */
-         if(this->function.nesting_depth == 0 && ir->get_next()->is_tail_sentinel())
-            lower = false;
-         else if (this->function.is_main)
-            lower = lower_main_return;
-         else
-            lower = lower_sub_return;
-         break;
-      case strength_discard:
-         lower = false; /* probably nothing needs this lowered */
-         break;
-      }
-      return lower;
-   }
-
-   block_record visit_block(exec_list* list)
-   {
-      block_record saved_block = this->block;
-      this->block = block_record();
-      visit_exec_list(list, this);
-      block_record ret = this->block;
-      this->block = saved_block;
-      return ret;
-   }
-
-   virtual void visit(ir_if *ir)
-   {
-      if(this->loop.nesting_depth == 0 && ir->get_next()->is_tail_sentinel())
-         this->loop.in_if_at_the_end_of_the_loop = true;
-
-      ++this->function.nesting_depth;
-      ++this->loop.nesting_depth;
-
-      block_record block_records[2];
-      ir_jump* jumps[2];
-
-      block_records[0] = visit_block(&ir->then_instructions);
-      block_records[1] = visit_block(&ir->else_instructions);
-
-retry: /* we get here if we put code after the if inside a branch */
-   for(unsigned i = 0; i < 2; ++i) {
-      exec_list& list = i ? ir->else_instructions : ir->then_instructions;
-      jumps[i] = 0;
-      if(!list.is_empty() && get_jump_strength((ir_instruction*)list.get_tail()))
-         jumps[i] = (ir_jump*)list.get_tail();
-   }
-
-      for(;;) {
-         jump_strength jump_strengths[2];
-
-         for(unsigned i = 0; i < 2; ++i) {
-            if(jumps[i]) {
-               jump_strengths[i] = block_records[i].min_strength;
-               assert(jump_strengths[i] == get_jump_strength(jumps[i]));
-            } else
-               jump_strengths[i] = strength_none;
-         }
-
-         /* move both jumps out if possible */
-         if(pull_out_jumps && jump_strengths[0] == jump_strengths[1]) {
-            bool unify = true;
-            if(jump_strengths[0] == strength_continue)
-               ir->insert_after(new(ir) ir_loop_jump(ir_loop_jump::jump_continue));
-            else if(jump_strengths[0] == strength_break)
-               ir->insert_after(new(ir) ir_loop_jump(ir_loop_jump::jump_break));
-            /* FINISHME: unify returns with identical expressions */
-            else if(jump_strengths[0] == strength_return && this->function.signature->return_type->is_void())
-               ir->insert_after(new(ir) ir_return(NULL));
-            /* FINISHME: unify discards */
-            else
-               unify = false;
-
-            if(unify) {
-               jumps[0]->remove();
-               jumps[1]->remove();
-               this->progress = true;
-
-               jumps[0] = 0;
-               jumps[1] = 0;
-               block_records[0].min_strength = strength_none;
-               block_records[1].min_strength = strength_none;
-               break;
-            }
-         }
-
-         /* lower a jump: if both need to lowered, start with the strongest one, so that
-          * we might later unify the lowered version with the other one
-          */
-         bool should_lower[2];
-         for(unsigned i = 0; i < 2; ++i)
-            should_lower[i] = should_lower_jump(jumps[i]);
-
-         int lower;
-         if(should_lower[1] && should_lower[0])
-            lower = jump_strengths[1] > jump_strengths[0];
-         else if(should_lower[0])
-            lower = 0;
-         else if(should_lower[1])
-            lower = 1;
-         else
-            break;
-
-         if(jump_strengths[lower] == strength_return) {
-            ir_variable* return_flag = this->function.get_return_flag();
-            if(!this->function.signature->return_type->is_void()) {
-               ir_variable* return_value = this->function.get_return_value();
-               jumps[lower]->insert_before(new(ir) ir_assignment(new (ir) ir_dereference_variable(return_value), ((ir_return*)jumps[lower])->value, NULL));
-            }
-            jumps[lower]->insert_before(new(ir) ir_assignment(new (ir) ir_dereference_variable(return_flag), new (ir) ir_constant(true), NULL));
-            this->loop.may_set_return_flag = true;
-            if(this->loop.loop) {
-               ir_loop_jump* lowered = 0;
-               lowered = new(ir) ir_loop_jump(ir_loop_jump::jump_break);
-               block_records[lower].min_strength = strength_break;
-               jumps[lower]->replace_with(lowered);
-               jumps[lower] = lowered;
-            } else
-               goto lower_continue;
-            this->progress = true;
-         } else if(jump_strengths[lower] == strength_break) {
-            /* We can't lower to an actual continue because that would execute the increment.
-             *
-             * In the lowered code, we instead put the break check between the this->loop body and the increment,
-             * which is impossible with a real continue as defined by the GLSL IR currently.
-             *
-             * Smarter options (such as undoing the increment) are possible but it's not worth implementing them,
-             * because if break is lowered, continue is almost surely lowered too.
-             */
-            jumps[lower]->insert_before(new(ir) ir_assignment(new (ir) ir_dereference_variable(this->loop.get_break_flag()), new (ir) ir_constant(true), 0));
-            goto lower_continue;
-         } else if(jump_strengths[lower] == strength_continue) {
-lower_continue:
-            ir_variable* execute_flag = this->loop.get_execute_flag();
-            jumps[lower]->replace_with(new(ir) ir_assignment(new (ir) ir_dereference_variable(execute_flag), new (ir) ir_constant(false), 0));
-            jumps[lower] = 0;
-            block_records[lower].min_strength = strength_always_clears_execute_flag;
-            block_records[lower].may_clear_execute_flag = true;
-            this->progress = true;
-            break;
-         }
-      }
-
-      /* move out a jump out if possible */
-      if(pull_out_jumps) {
-         int move_out = -1;
-         if(jumps[0] && block_records[1].min_strength >= strength_continue)
-            move_out = 0;
-         else if(jumps[1] && block_records[0].min_strength >= strength_continue)
-            move_out = 1;
-
-         if(move_out >= 0)
-         {
-            jumps[move_out]->remove();
-            ir->insert_after(jumps[move_out]);
-            jumps[move_out] = 0;
-            block_records[move_out].min_strength = strength_none;
-            this->progress = true;
-         }
-      }
-
-      if(block_records[0].min_strength < block_records[1].min_strength)
-         this->block.min_strength = block_records[0].min_strength;
-      else
-         this->block.min_strength = block_records[1].min_strength;
-      this->block.may_clear_execute_flag = this->block.may_clear_execute_flag || block_records[0].may_clear_execute_flag || block_records[1].may_clear_execute_flag;
-
-      if(this->block.min_strength)
-         truncate_after_instruction(ir);
-      else if(this->block.may_clear_execute_flag)
-      {
-         int move_into = -1;
-         if(block_records[0].min_strength && !block_records[1].may_clear_execute_flag)
-            move_into = 1;
-         else if(block_records[1].min_strength && !block_records[0].may_clear_execute_flag)
-            move_into = 0;
-
-         if(move_into >= 0) {
-            assert(!block_records[move_into].min_strength && !block_records[move_into].may_clear_execute_flag); /* otherwise, we just truncated */
-
-            exec_list* list = move_into ? &ir->else_instructions : &ir->then_instructions;
-            exec_node* next = ir->get_next();
-            if(!next->is_tail_sentinel()) {
-               move_outer_block_inside(ir, list);
-
-               exec_list list;
-               list.head = next;
-               block_records[move_into] = visit_block(&list);
-
-               this->progress = true;
-               goto retry;
-            }
-         } else {
-            ir_instruction* ir_after;
-            for(ir_after = (ir_instruction*)ir->get_next(); !ir_after->is_tail_sentinel();)
-            {
-               ir_if* ir_if = ir_after->as_if();
-               if(ir_if && ir_if->else_instructions.is_empty()) {
-                  ir_dereference_variable* ir_if_cond_deref = ir_if->condition->as_dereference_variable();
-                  if(ir_if_cond_deref && ir_if_cond_deref->var == this->loop.execute_flag) {
-                     ir_instruction* ir_next = (ir_instruction*)ir_after->get_next();
-                     ir_after->insert_before(&ir_if->then_instructions);
-                     ir_after->remove();
-                     ir_after = ir_next;
-                     continue;
-                  }
-               }
-               ir_after = (ir_instruction*)ir_after->get_next();
-
-               /* only set this if we find any unprotected instruction */
-               this->progress = true;
-            }
-
-            if(!ir->get_next()->is_tail_sentinel()) {
-               assert(this->loop.execute_flag);
-               ir_if* if_execute = new(ir) ir_if(new(ir) ir_dereference_variable(this->loop.execute_flag));
-               move_outer_block_inside(ir, &if_execute->then_instructions);
-               ir->insert_after(if_execute);
-            }
-         }
-      }
-      --this->loop.nesting_depth;
-      --this->function.nesting_depth;
-   }
-
-   virtual void visit(ir_loop *ir)
-   {
-      ++this->function.nesting_depth;
-      loop_record saved_loop = this->loop;
-      this->loop = loop_record(this->function.signature, ir);
-
-      block_record body = visit_block(&ir->body_instructions);
-
-      if(body.min_strength >= strength_break) {
-         /* FINISHME: turn the this->loop into an if, or replace it with its body */
-      }
-
-      if(this->loop.break_flag) {
-         ir_if* break_if = new(ir) ir_if(new(ir) ir_dereference_variable(this->loop.break_flag));
-         break_if->then_instructions.push_tail(new(ir) ir_loop_jump(ir_loop_jump::jump_break));
-         ir->body_instructions.push_tail(break_if);
-      }
-
-      if(this->loop.may_set_return_flag) {
-         assert(this->function.return_flag);
-         ir_if* return_if = new(ir) ir_if(new(ir) ir_dereference_variable(this->function.return_flag));
-         return_if->then_instructions.push_tail(new(ir) ir_loop_jump(saved_loop.loop ? ir_loop_jump::jump_break : ir_loop_jump::jump_continue));
-         ir->insert_after(return_if);
-      }
-
-      this->loop = saved_loop;
-      --this->function.nesting_depth;
-   }
-
-   virtual void visit(ir_function_signature *ir)
-   {
-      /* these are not strictly necessary */
-      assert(!this->function.signature);
-      assert(!this->loop.loop);
-
-      function_record saved_function = this->function;
-      loop_record saved_loop = this->loop;
-      this->function = function_record(ir);
-      this->loop = loop_record(ir);
-
-      assert(!this->loop.loop);
-      visit_block(&ir->body);
-
-      if(this->function.return_value)
-         ir->body.push_tail(new(ir) ir_return(new (ir) ir_dereference_variable(this->function.return_value)));
-
-      this->loop = saved_loop;
-      this->function = saved_function;
-   }
-
-   virtual void visit(class ir_function * ir)
-   {
-      visit_block(&ir->signatures);
-   }
-};
-
-bool
-do_lower_jumps(exec_list *instructions, bool pull_out_jumps, bool lower_sub_return, bool lower_main_return, bool lower_continue, bool lower_break)
-{
-   ir_lower_jumps_visitor v;
-   v.pull_out_jumps = pull_out_jumps;
-   v.lower_continue = lower_continue;
-   v.lower_break = lower_break;
-   v.lower_sub_return = lower_sub_return;
-   v.lower_main_return = lower_main_return;
-
-   do {
-      v.progress = false;
-      visit_exec_list(instructions, &v);
-   } while (v.progress);
-
-   return v.progress;
-}