From: Jordan Justen Date: Sat, 10 Oct 2015 14:55:42 +0000 (-0700) Subject: glsl: Translate atomic intrinsic functions on shared variables X-Git-Url: https://git.libre-soc.org/?a=commitdiff_plain;h=7333593cf3141e61610f25f86e8b5282c8db099e;p=mesa.git glsl: Translate atomic intrinsic functions on shared variables When an intrinsic atomic operation is used on a shared variable, we translate it to a new 'shared variable' specific intrinsic function call. For example, a call to __intrinsic_atomic_add when used on a shared variable will be translated to a call to __intrinsic_atomic_add_shared. v3: * Fix stale comments copied from SSBOs (Iago) Signed-off-by: Jordan Justen Reviewed-by: Iago Toral Quiroga Reviewed-by: Kristian Høgsberg --- diff --git a/src/glsl/lower_shared_reference.cpp b/src/glsl/lower_shared_reference.cpp index 4bac5d53262..533cd9202f4 100644 --- a/src/glsl/lower_shared_reference.cpp +++ b/src/glsl/lower_shared_reference.cpp @@ -76,6 +76,10 @@ public: ir_visitor_status visit_enter(ir_assignment *ir); void handle_assignment(ir_assignment *ir); + ir_call *lower_shared_atomic_intrinsic(ir_call *ir); + ir_call *check_for_shared_atomic_intrinsic(ir_call *ir); + ir_visitor_status visit_enter(ir_call *ir); + unsigned get_shared_offset(const ir_variable *); ir_call *shared_load(void *mem_ctx, const struct glsl_type *type, @@ -324,6 +328,150 @@ lower_shared_reference_visitor::shared_load(void *mem_ctx, return new(mem_ctx) ir_call(sig, deref_result, &call_params); } +/* Lowers the intrinsic call to a new internal intrinsic that swaps the access + * to the shared variable in the first parameter by an offset. This involves + * creating the new internal intrinsic (i.e. the new function signature). + */ +ir_call * +lower_shared_reference_visitor::lower_shared_atomic_intrinsic(ir_call *ir) +{ + /* Shared atomics usually have 2 parameters, the shared variable and an + * integer argument. The exception is CompSwap, that has an additional + * integer parameter. + */ + int param_count = ir->actual_parameters.length(); + assert(param_count == 2 || param_count == 3); + + /* First argument must be a scalar integer shared variable */ + exec_node *param = ir->actual_parameters.get_head(); + ir_instruction *inst = (ir_instruction *) param; + assert(inst->ir_type == ir_type_dereference_variable || + inst->ir_type == ir_type_dereference_array || + inst->ir_type == ir_type_dereference_record || + inst->ir_type == ir_type_swizzle); + + ir_rvalue *deref = (ir_rvalue *) inst; + assert(deref->type->is_scalar() && deref->type->is_integer()); + + ir_variable *var = deref->variable_referenced(); + assert(var); + + /* Compute the offset to the start if the dereference + */ + void *mem_ctx = ralloc_parent(shader->ir); + + ir_rvalue *offset = NULL; + unsigned const_offset = get_shared_offset(var); + bool row_major; + int matrix_columns; + assert(var->get_interface_type() == NULL); + const unsigned packing = GLSL_INTERFACE_PACKING_STD430; + buffer_access_type = shared_atomic_access; + + setup_buffer_access(mem_ctx, var, deref, + &offset, &const_offset, + &row_major, &matrix_columns, packing); + + assert(offset); + assert(!row_major); + assert(matrix_columns == 1); + + ir_rvalue *deref_offset = + add(offset, new(mem_ctx) ir_constant(const_offset)); + + /* Create the new internal function signature that will take an offset + * instead of a shared variable + */ + exec_list sig_params; + ir_variable *sig_param = new(mem_ctx) + ir_variable(glsl_type::uint_type, "offset" , ir_var_function_in); + sig_params.push_tail(sig_param); + + const glsl_type *type = deref->type->base_type == GLSL_TYPE_INT ? + glsl_type::int_type : glsl_type::uint_type; + sig_param = new(mem_ctx) + ir_variable(type, "data1", ir_var_function_in); + sig_params.push_tail(sig_param); + + if (param_count == 3) { + sig_param = new(mem_ctx) + ir_variable(type, "data2", ir_var_function_in); + sig_params.push_tail(sig_param); + } + + ir_function_signature *sig = + new(mem_ctx) ir_function_signature(deref->type, + compute_shader_enabled); + assert(sig); + sig->replace_parameters(&sig_params); + sig->is_intrinsic = true; + + char func_name[64]; + sprintf(func_name, "%s_shared", ir->callee_name()); + ir_function *f = new(mem_ctx) ir_function(func_name); + f->add_signature(sig); + + /* Now, create the call to the internal intrinsic */ + exec_list call_params; + call_params.push_tail(deref_offset); + param = ir->actual_parameters.get_head()->get_next(); + ir_rvalue *param_as_rvalue = ((ir_instruction *) param)->as_rvalue(); + call_params.push_tail(param_as_rvalue->clone(mem_ctx, NULL)); + if (param_count == 3) { + param = param->get_next(); + param_as_rvalue = ((ir_instruction *) param)->as_rvalue(); + call_params.push_tail(param_as_rvalue->clone(mem_ctx, NULL)); + } + ir_dereference_variable *return_deref = + ir->return_deref->clone(mem_ctx, NULL); + return new(mem_ctx) ir_call(sig, return_deref, &call_params); +} + +ir_call * +lower_shared_reference_visitor::check_for_shared_atomic_intrinsic(ir_call *ir) +{ + exec_list& params = ir->actual_parameters; + + if (params.length() < 2 || params.length() > 3) + return ir; + + ir_rvalue *rvalue = + ((ir_instruction *) params.get_head())->as_rvalue(); + if (!rvalue) + return ir; + + ir_variable *var = rvalue->variable_referenced(); + if (!var || var->data.mode != ir_var_shader_shared) + return ir; + + const char *callee = ir->callee_name(); + if (!strcmp("__intrinsic_atomic_add", callee) || + !strcmp("__intrinsic_atomic_min", callee) || + !strcmp("__intrinsic_atomic_max", callee) || + !strcmp("__intrinsic_atomic_and", callee) || + !strcmp("__intrinsic_atomic_or", callee) || + !strcmp("__intrinsic_atomic_xor", callee) || + !strcmp("__intrinsic_atomic_exchange", callee) || + !strcmp("__intrinsic_atomic_comp_swap", callee)) { + return lower_shared_atomic_intrinsic(ir); + } + + return ir; +} + +ir_visitor_status +lower_shared_reference_visitor::visit_enter(ir_call *ir) +{ + ir_call *new_ir = check_for_shared_atomic_intrinsic(ir); + if (new_ir != ir) { + progress = true; + base_ir->replace_with(new_ir); + return visit_continue_with_parent; + } + + return rvalue_visit(ir); +} + } /* unnamed namespace */ void