diff options
| -rw-r--r-- | src/compiler/glsl/loop_analysis.cpp | 139 | ||||
| -rw-r--r-- | src/compiler/glsl/loop_analysis.h | 7 | ||||
| -rw-r--r-- | src/compiler/glsl/loop_controls.cpp | 139 |
3 files changed, 139 insertions, 146 deletions
diff --git a/src/compiler/glsl/loop_analysis.cpp b/src/compiler/glsl/loop_analysis.cpp index b9bae435368..81a07f78f8f 100644 --- a/src/compiler/glsl/loop_analysis.cpp +++ b/src/compiler/glsl/loop_analysis.cpp @@ -32,6 +32,145 @@ static bool all_expression_operands_are_loop_constant(ir_rvalue *, static ir_rvalue *get_basic_induction_increment(ir_assignment *, hash_table *); +/** + * Find an initializer of a variable outside a loop + * + * Works backwards from the loop to find the pre-loop value of the variable. + * This is used, for example, to find the initial value of loop induction + * variables. + * + * \param loop Loop where \c var is an induction variable + * \param var Variable whose initializer is to be found + * + * \return + * The \c ir_rvalue assigned to the variable outside the loop. May return + * \c NULL if no initializer can be found. + */ +static ir_rvalue * +find_initial_value(ir_loop *loop, ir_variable *var) +{ + for (exec_node *node = loop->prev; !node->is_head_sentinel(); + node = node->prev) { + ir_instruction *ir = (ir_instruction *) node; + + switch (ir->ir_type) { + case ir_type_call: + case ir_type_loop: + case ir_type_loop_jump: + case ir_type_return: + case ir_type_if: + return NULL; + + case ir_type_function: + case ir_type_function_signature: + assert(!"Should not get here."); + return NULL; + + case ir_type_assignment: { + ir_assignment *assign = ir->as_assignment(); + ir_variable *assignee = assign->lhs->whole_variable_referenced(); + + if (assignee == var) + return (assign->condition != NULL) ? NULL : assign->rhs; + + break; + } + + default: + break; + } + } + + return NULL; +} + + +static int +calculate_iterations(ir_rvalue *from, ir_rvalue *to, ir_rvalue *increment, + enum ir_expression_operation op) +{ + if (from == NULL || to == NULL || increment == NULL) + return -1; + + void *mem_ctx = ralloc_context(NULL); + + ir_expression *const sub = + new(mem_ctx) ir_expression(ir_binop_sub, from->type, to, from); + + ir_expression *const div = + new(mem_ctx) ir_expression(ir_binop_div, sub->type, sub, increment); + + ir_constant *iter = div->constant_expression_value(mem_ctx); + if (iter == NULL) { + ralloc_free(mem_ctx); + return -1; + } + + if (!iter->type->is_integer()) { + const ir_expression_operation op = iter->type->is_double() + ? ir_unop_d2i : ir_unop_f2i; + ir_rvalue *cast = + new(mem_ctx) ir_expression(op, glsl_type::int_type, iter, NULL); + + iter = cast->constant_expression_value(mem_ctx); + } + + int iter_value = iter->get_int_component(0); + + /* Make sure that the calculated number of iterations satisfies the exit + * condition. This is needed to catch off-by-one errors and some types of + * ill-formed loops. For example, we need to detect that the following + * loop does not have a maximum iteration count. + * + * for (float x = 0.0; x != 0.9; x += 0.2) + * ; + */ + const int bias[] = { -1, 0, 1 }; + bool valid_loop = false; + + for (unsigned i = 0; i < ARRAY_SIZE(bias); i++) { + /* Increment may be of type int, uint or float. */ + switch (increment->type->base_type) { + case GLSL_TYPE_INT: + iter = new(mem_ctx) ir_constant(iter_value + bias[i]); + break; + case GLSL_TYPE_UINT: + iter = new(mem_ctx) ir_constant(unsigned(iter_value + bias[i])); + break; + case GLSL_TYPE_FLOAT: + iter = new(mem_ctx) ir_constant(float(iter_value + bias[i])); + break; + case GLSL_TYPE_DOUBLE: + iter = new(mem_ctx) ir_constant(double(iter_value + bias[i])); + break; + default: + unreachable("Unsupported type for loop iterator."); + } + + ir_expression *const mul = + new(mem_ctx) ir_expression(ir_binop_mul, increment->type, iter, + increment); + + ir_expression *const add = + new(mem_ctx) ir_expression(ir_binop_add, mul->type, mul, from); + + ir_expression *const cmp = + new(mem_ctx) ir_expression(op, glsl_type::bool_type, add, to); + + ir_constant *const cmp_result = cmp->constant_expression_value(mem_ctx); + + assert(cmp_result != NULL); + if (cmp_result->get_bool_component(0)) { + iter_value += bias[i]; + valid_loop = true; + break; + } + } + + ralloc_free(mem_ctx); + return (valid_loop) ? iter_value : -1; +} + /** * Record the fact that the given loop variable was referenced inside the loop. diff --git a/src/compiler/glsl/loop_analysis.h b/src/compiler/glsl/loop_analysis.h index 2894c6359be..e2eff9dbaed 100644 --- a/src/compiler/glsl/loop_analysis.h +++ b/src/compiler/glsl/loop_analysis.h @@ -55,13 +55,6 @@ extern bool unroll_loops(exec_list *instructions, loop_state *ls, const struct gl_shader_compiler_options *options); -ir_rvalue * -find_initial_value(ir_loop *loop, ir_variable *var); - -int -calculate_iterations(ir_rvalue *from, ir_rvalue *to, ir_rvalue *increment, - enum ir_expression_operation op); - /** * Tracking for all variables used in a loop diff --git a/src/compiler/glsl/loop_controls.cpp b/src/compiler/glsl/loop_controls.cpp index 895954fc2d1..ad4aa189411 100644 --- a/src/compiler/glsl/loop_controls.cpp +++ b/src/compiler/glsl/loop_controls.cpp @@ -27,145 +27,6 @@ #include "loop_analysis.h" #include "ir_hierarchical_visitor.h" -/** - * Find an initializer of a variable outside a loop - * - * Works backwards from the loop to find the pre-loop value of the variable. - * This is used, for example, to find the initial value of loop induction - * variables. - * - * \param loop Loop where \c var is an induction variable - * \param var Variable whose initializer is to be found - * - * \return - * The \c ir_rvalue assigned to the variable outside the loop. May return - * \c NULL if no initializer can be found. - */ -ir_rvalue * -find_initial_value(ir_loop *loop, ir_variable *var) -{ - for (exec_node *node = loop->prev; - !node->is_head_sentinel(); - node = node->prev) { - ir_instruction *ir = (ir_instruction *) node; - - switch (ir->ir_type) { - case ir_type_call: - case ir_type_loop: - case ir_type_loop_jump: - case ir_type_return: - case ir_type_if: - return NULL; - - case ir_type_function: - case ir_type_function_signature: - assert(!"Should not get here."); - return NULL; - - case ir_type_assignment: { - ir_assignment *assign = ir->as_assignment(); - ir_variable *assignee = assign->lhs->whole_variable_referenced(); - - if (assignee == var) - return (assign->condition != NULL) ? NULL : assign->rhs; - - break; - } - - default: - break; - } - } - - return NULL; -} - - -int -calculate_iterations(ir_rvalue *from, ir_rvalue *to, ir_rvalue *increment, - enum ir_expression_operation op) -{ - if (from == NULL || to == NULL || increment == NULL) - return -1; - - void *mem_ctx = ralloc_context(NULL); - - ir_expression *const sub = - new(mem_ctx) ir_expression(ir_binop_sub, from->type, to, from); - - ir_expression *const div = - new(mem_ctx) ir_expression(ir_binop_div, sub->type, sub, increment); - - ir_constant *iter = div->constant_expression_value(mem_ctx); - if (iter == NULL) { - ralloc_free(mem_ctx); - return -1; - } - - if (!iter->type->is_integer()) { - const ir_expression_operation op = iter->type->is_double() - ? ir_unop_d2i : ir_unop_f2i; - ir_rvalue *cast = - new(mem_ctx) ir_expression(op, glsl_type::int_type, iter, NULL); - - iter = cast->constant_expression_value(mem_ctx); - } - - int iter_value = iter->get_int_component(0); - - /* Make sure that the calculated number of iterations satisfies the exit - * condition. This is needed to catch off-by-one errors and some types of - * ill-formed loops. For example, we need to detect that the following - * loop does not have a maximum iteration count. - * - * for (float x = 0.0; x != 0.9; x += 0.2) - * ; - */ - const int bias[] = { -1, 0, 1 }; - bool valid_loop = false; - - for (unsigned i = 0; i < ARRAY_SIZE(bias); i++) { - /* Increment may be of type int, uint or float. */ - switch (increment->type->base_type) { - case GLSL_TYPE_INT: - iter = new(mem_ctx) ir_constant(iter_value + bias[i]); - break; - case GLSL_TYPE_UINT: - iter = new(mem_ctx) ir_constant(unsigned(iter_value + bias[i])); - break; - case GLSL_TYPE_FLOAT: - iter = new(mem_ctx) ir_constant(float(iter_value + bias[i])); - break; - case GLSL_TYPE_DOUBLE: - iter = new(mem_ctx) ir_constant(double(iter_value + bias[i])); - break; - default: - unreachable("Unsupported type for loop iterator."); - } - - ir_expression *const mul = - new(mem_ctx) ir_expression(ir_binop_mul, increment->type, iter, - increment); - - ir_expression *const add = - new(mem_ctx) ir_expression(ir_binop_add, mul->type, mul, from); - - ir_expression *const cmp = - new(mem_ctx) ir_expression(op, glsl_type::bool_type, add, to); - - ir_constant *const cmp_result = cmp->constant_expression_value(mem_ctx); - - assert(cmp_result != NULL); - if (cmp_result->get_bool_component(0)) { - iter_value += bias[i]; - valid_loop = true; - break; - } - } - - ralloc_free(mem_ctx); - return (valid_loop) ? iter_value : -1; -} namespace { |