diff options
| -rw-r--r-- | src/glsl/ir_algebraic.cpp | 108 |
1 files changed, 107 insertions, 1 deletions
diff --git a/src/glsl/ir_algebraic.cpp b/src/glsl/ir_algebraic.cpp index 43d8f9e699c..86fb7e49c03 100644 --- a/src/glsl/ir_algebraic.cpp +++ b/src/glsl/ir_algebraic.cpp @@ -58,7 +58,14 @@ public: virtual ir_visitor_status visit_leave(ir_texture *); ir_rvalue *handle_expression(ir_rvalue *in_ir); - + bool reassociate_constant(ir_expression *ir1, + int const_index, + ir_constant *constant, + ir_expression *ir2); + void reassociate_operands(ir_expression *ir1, + int op1, + ir_expression *ir2, + int op2); bool progress; }; @@ -138,6 +145,84 @@ is_vec_one(ir_constant *ir) return true; } +static void +update_type(ir_expression *ir) +{ + if (ir->operands[0]->type->is_vector()) + ir->type = ir->operands[0]->type; + else + ir->type = ir->operands[1]->type; +} + +void +ir_algebraic_visitor::reassociate_operands(ir_expression *ir1, + int op1, + ir_expression *ir2, + int op2) +{ + ir_rvalue *temp = ir2->operands[op2]; + ir2->operands[op2] = ir1->operands[op1]; + ir1->operands[op1] = temp; + + /* Update the type of ir2. The type of ir1 won't have changed -- + * base types matched, and at least one of the operands of the 2 + * binops is still a vector if any of them were. + */ + update_type(ir2); + + this->progress = true; +} + +/** + * Reassociates a constant down a tree of adds or multiplies. + * + * Consider (2 * (a * (b * 0.5))). We want to send up with a * b. + */ +bool +ir_algebraic_visitor::reassociate_constant(ir_expression *ir1, int const_index, + ir_constant *constant, + ir_expression *ir2) +{ + if (!ir2 || ir1->operation != ir2->operation) + return false; + + /* Don't want to even think about matrices. */ + if (ir1->operands[0]->type->is_matrix() || + ir1->operands[0]->type->is_matrix() || + ir2->operands[1]->type->is_matrix() || + ir2->operands[1]->type->is_matrix()) + return false; + + ir_constant *ir2_const[2]; + ir2_const[0] = ir2->operands[0]->constant_expression_value(); + ir2_const[1] = ir2->operands[1]->constant_expression_value(); + + if (ir2_const[0] && ir2_const[1]) + return false; + + if (ir2_const[0]) { + reassociate_operands(ir1, const_index, ir2, 1); + return true; + } else if (ir2_const[1]) { + reassociate_operands(ir1, const_index, ir2, 0); + return true; + } + + if (reassociate_constant(ir1, const_index, constant, + ir2->operands[0]->as_expression())) { + update_type(ir2); + return true; + } + + if (reassociate_constant(ir1, const_index, constant, + ir2->operands[1]->as_expression())) { + update_type(ir2); + return true; + } + + return false; +} + ir_rvalue * ir_algebraic_visitor::handle_expression(ir_rvalue *in_ir) { @@ -201,6 +286,16 @@ ir_algebraic_visitor::handle_expression(ir_rvalue *in_ir) this->progress = true; return ir->operands[0]; } + + /* Reassociate addition of constants so that we can do constant + * folding. + */ + if (op_const[0] && !op_const[1]) + reassociate_constant(ir, 0, op_const[0], + ir->operands[1]->as_expression()); + if (op_const[1] && !op_const[0]) + reassociate_constant(ir, 1, op_const[1], + ir->operands[0]->as_expression()); break; case ir_binop_sub: @@ -231,6 +326,17 @@ ir_algebraic_visitor::handle_expression(ir_rvalue *in_ir) this->progress = true; return ir_constant::zero(ir, ir->type); } + + /* Reassociate multiplication of constants so that we can do + * constant folding. + */ + if (op_const[0] && !op_const[1]) + reassociate_constant(ir, 0, op_const[0], + ir->operands[1]->as_expression()); + if (op_const[1] && !op_const[0]) + reassociate_constant(ir, 1, op_const[1], + ir->operands[0]->as_expression()); + break; case ir_binop_div: |