/**
* Perform some fixups for variadic functions.
* To make the rest of the frontend code easier to understand we add
* "dummy" parameters until the number of parameters transmitted in registers.
* (because otherwise the backend wouldn't store the value of the register
* parameters into memory for the VLA magic)
*/
static bool sparc_variadic_fixups(ir_graph *const irg, calling_convention_t *const cconv)
{
ir_entity *entity = get_irg_entity(irg);
ir_type *mtp = get_entity_type(entity);
if (!is_method_variadic(mtp))
return false;
if (cconv->n_param_regs >= SPARC_N_PARAM_REGS)
return false;
size_t const n_params = get_method_n_params(mtp);
size_t const n_ress = get_method_n_ress(mtp);
size_t const new_n_params = n_params + (SPARC_N_PARAM_REGS - cconv->n_param_regs);
unsigned const cc_mask = get_method_calling_convention(mtp);
mtp_additional_properties const props = get_method_additional_properties(mtp);
ir_type *const new_mtp = new_type_method(new_n_params, n_ress, true, cc_mask, props);
type_dbg_info *const dbgi = get_type_dbg_info(mtp);
set_type_dbg_info(new_mtp, dbgi);
for (size_t i = 0; i < n_ress; ++i) {
ir_type *type = get_method_res_type(mtp, i);
set_method_res_type(new_mtp, i, type);
}
for (size_t i = 0; i < n_params; ++i) {
ir_type *type = get_method_param_type(mtp, i);
set_method_param_type(new_mtp, i, type);
}
ir_type *const frame_type = get_irg_frame_type(irg);
ir_mode *const gp_reg_mode = sparc_reg_classes[CLASS_sparc_gp].mode;
ir_type *const gp_reg_type = get_type_for_mode(gp_reg_mode);
for (size_t i = n_params; i < new_n_params; ++i) {
set_method_param_type(new_mtp, i, gp_reg_type);
new_parameter_entity(frame_type, i, gp_reg_type);
}
set_entity_type(entity, new_mtp);
return true;
}
calling_convention_t *sparc_decide_calling_convention(ir_type *function_type,
ir_graph *irg)
{
bool omit_fp = false;
if (irg != NULL) {
omit_fp = be_options.omit_fp;
/* our current vaarg handling needs the standard space to store the
* args 0-5 in it */
if (is_method_variadic(function_type))
omit_fp = false;
/* The pointer to the aggregate return value belongs to the 92 magic bytes.
* Thus, if the called functions increases the stack size,
* it must copy the value to the appropriate location.
* This is not implemented yet, so we forbid to omit the frame pointer.
*/
if (get_method_calling_convention(function_type) & cc_compound_ret)
omit_fp = false;
if (omit_fp)
irg_walk_graph(irg, check_omit_fp, NULL, &omit_fp);
sparc_get_irg_data(irg)->omit_fp = omit_fp;
}
mtp_additional_properties mtp
= get_method_additional_properties(function_type);
unsigned *caller_saves = rbitset_malloc(N_SPARC_REGISTERS);
if (mtp & mtp_property_returns_twice) {
rbitset_copy(caller_saves, default_returns_twice_saves,
N_SPARC_REGISTERS);
} else {
rbitset_copy(caller_saves, default_caller_saves, N_SPARC_REGISTERS);
}
/* determine how parameters are passed */
int n_params = get_method_n_params(function_type);
int regnum = 0;
reg_or_stackslot_t *params = XMALLOCNZ(reg_or_stackslot_t, n_params);
int n_param_regs = ARRAY_SIZE(param_regs);
unsigned stack_offset = !omit_fp ? SPARC_MIN_STACKSIZE : 0;
for (int i = 0; i < n_params; ++i) {
ir_type *param_type = get_method_param_type(function_type,i);
ir_mode *mode;
int bits;
reg_or_stackslot_t *param;
if (is_compound_type(param_type))
panic("compound arguments not supported yet");
mode = get_type_mode(param_type);
bits = get_mode_size_bits(mode);
param = ¶ms[i];
if (i == 0 &&
(get_method_calling_convention(function_type) & cc_compound_ret)) {
assert(mode_is_reference(mode) && bits == 32);
/* special case, we have reserved space for this on the between
* type */
param->type = param_type;
param->offset = SPARC_AGGREGATE_RETURN_OFFSET;
param->already_stored = true;
continue;
}
if (regnum < n_param_regs) {
param->offset = SPARC_PARAMS_SPILL_OFFSET
+ regnum * SPARC_REGISTER_SIZE;
param->type = param_type;
arch_register_t const *reg = param_regs[regnum++];
if (irg == NULL || omit_fp)
reg = map_i_to_o_reg(reg);
param->reg0 = reg;
param->req0 = reg->single_req;
} else {
param->type = param_type;
param->offset = stack_offset;
param->already_stored = true;
/* increase offset by at least SPARC_REGISTER_SIZE bytes so
* everything is aligned */
stack_offset += MAX(bits / 8, SPARC_REGISTER_SIZE);
continue;
}
/* we might need a 2nd 32bit component (for 64bit or double values) */
if (bits > 32) {
if (bits > 64)
panic("only 32 and 64bit modes supported");
if (regnum < n_param_regs) {
param->offset = SPARC_PARAMS_SPILL_OFFSET
+ regnum * SPARC_REGISTER_SIZE;
arch_register_t const *reg = param_regs[regnum++];
if (irg == NULL || omit_fp)
reg = map_i_to_o_reg(reg);
param->reg1 = reg;
param->req1 = reg->single_req;
} else {
ir_mode *regmode = param_regs[0]->cls->mode;
ir_type *type = get_type_for_mode(regmode);
param->type = type;
param->offset = stack_offset;
assert(get_mode_size_bits(regmode) == 32);
stack_offset += SPARC_REGISTER_SIZE;
}
}
}
unsigned n_param_regs_used = regnum;
/* determine how results are passed */
int n_results = get_method_n_ress(function_type);
unsigned float_regnum = 0;
unsigned n_reg_results = 0;
unsigned n_float_result_regs = ARRAY_SIZE(float_result_regs);
reg_or_stackslot_t *results = XMALLOCNZ(reg_or_stackslot_t, n_results);
regnum = 0;
for (int i = 0; i < n_results; ++i) {
ir_type *result_type = get_method_res_type(function_type, i);
ir_mode *result_mode = get_type_mode(result_type);
reg_or_stackslot_t *result = &results[i];
if (mode_is_float(result_mode)) {
unsigned n_regs = determine_n_float_regs(result_mode);
unsigned next_reg = round_up2(float_regnum, n_regs);
if (next_reg >= n_float_result_regs) {
panic("too many float results");
} else {
const arch_register_t *reg = float_result_regs[next_reg];
rbitset_clear(caller_saves, reg->global_index);
if (n_regs == 1) {
result->req0 = reg->single_req;
} else if (n_regs == 2) {
result->req0 = &float_result_reqs_double[next_reg];
rbitset_clear(caller_saves, reg->global_index+1);
} else if (n_regs == 4) {
result->req0 = &float_result_reqs_quad[next_reg];
rbitset_clear(caller_saves, reg->global_index+1);
rbitset_clear(caller_saves, reg->global_index+2);
rbitset_clear(caller_saves, reg->global_index+3);
} else {
panic("invalid number of registers in result");
}
float_regnum = next_reg + n_regs;
++n_reg_results;
}
} else {
if (get_mode_size_bits(result_mode) > 32) {
panic("results with more than 32bits not supported yet");
}
if (regnum >= n_param_regs) {
panic("too many results");
} else {
const arch_register_t *reg = param_regs[regnum++];
if (irg == NULL || omit_fp)
reg = map_i_to_o_reg(reg);
result->req0 = reg->single_req;
rbitset_clear(caller_saves, reg->global_index);
++n_reg_results;
}
}
}
calling_convention_t *cconv = XMALLOCZ(calling_convention_t);
cconv->n_parameters = n_params;
cconv->parameters = params;
cconv->param_stack_size = stack_offset - SPARC_MIN_STACKSIZE;
cconv->n_param_regs = n_param_regs_used;
cconv->results = results;
cconv->omit_fp = omit_fp;
cconv->caller_saves = caller_saves;
cconv->n_reg_results = n_reg_results;
/* setup ignore register array */
if (irg != NULL) {
be_irg_t *birg = be_birg_from_irg(irg);
birg->allocatable_regs = be_cconv_alloc_all_regs(&birg->obst, N_SPARC_REGISTERS);
be_cconv_rem_regs(birg->allocatable_regs, ignore_regs, ARRAY_SIZE(ignore_regs));
}
return cconv;
}
x86_cconv_t *ia32_decide_calling_convention(ir_type *function_type,
ir_graph *irg)
{
bool omit_fp = false;
if (irg != NULL) {
omit_fp = be_options.omit_fp;
if (omit_fp)
irg_walk_graph(irg, check_omit_fp, NULL, &omit_fp);
}
mtp_additional_properties mtp
= get_method_additional_properties(function_type);
(void)mtp;
/* TODO: do something with cc_reg_param/cc_this_call */
unsigned *caller_saves = rbitset_malloc(N_IA32_REGISTERS);
unsigned *callee_saves = rbitset_malloc(N_IA32_REGISTERS);
rbitset_copy(caller_saves, default_caller_saves, N_IA32_REGISTERS);
rbitset_copy(callee_saves, default_callee_saves, N_IA32_REGISTERS);
/* determine how parameters are passed */
unsigned n_params = get_method_n_params(function_type);
unsigned param_regnum = 0;
unsigned float_param_regnum = 0;
reg_or_stackslot_t *params = XMALLOCNZ(reg_or_stackslot_t,
n_params);
unsigned n_param_regs = ARRAY_SIZE(default_param_regs);
unsigned n_float_param_regs = ARRAY_SIZE(float_param_regs);
unsigned stack_offset = 0;
for (unsigned i = 0; i < n_params; ++i) {
ir_type *param_type = get_method_param_type(function_type, i);
reg_or_stackslot_t *param = ¶ms[i];
if (is_aggregate_type(param_type)) {
param->type = param_type;
param->offset = stack_offset;
stack_offset += get_type_size_bytes(param_type);
goto align_stack;
}
ir_mode *mode = get_type_mode(param_type);
if (mode_is_float(mode) && float_param_regnum < n_float_param_regs) {
param->reg = float_param_regs[float_param_regnum++];
} else if (!mode_is_float(mode) && param_regnum < n_param_regs) {
param->reg = default_param_regs[param_regnum++];
} else {
param->type = param_type;
param->offset = stack_offset;
stack_offset += get_type_size_bytes(param_type);
align_stack:;
/* increase offset by at least IA32_REGISTER_SIZE bytes so
* everything is aligned */
unsigned misalign = stack_offset % IA32_REGISTER_SIZE;
if (misalign > 0)
stack_offset += IA32_REGISTER_SIZE - misalign;
}
}
unsigned n_param_regs_used = param_regnum + float_param_regnum;
/* determine how results are passed */
unsigned n_results = get_method_n_ress(function_type);
unsigned n_reg_results = 0;
reg_or_stackslot_t *results = XMALLOCNZ(reg_or_stackslot_t, n_results);
unsigned res_regnum = 0;
unsigned res_float_regnum = 0;
unsigned n_result_regs = ARRAY_SIZE(result_regs);
unsigned n_float_result_regs = ARRAY_SIZE(float_result_regs);
for (size_t i = 0; i < n_results; ++i) {
ir_type *result_type = get_method_res_type(function_type, i);
ir_mode *result_mode = get_type_mode(result_type);
reg_or_stackslot_t *result = &results[i];
const arch_register_t *reg;
if (mode_is_float(result_mode)) {
if (res_float_regnum >= n_float_result_regs) {
panic("too many floating points results");
}
reg = float_result_regs[res_float_regnum++];
} else {
if (res_regnum >= n_result_regs) {
panic("too many results");
}
reg = result_regs[res_regnum++];
}
result->reg = reg;
rbitset_clear(caller_saves, reg->global_index);
++n_reg_results;
}
calling_convention cc = get_method_calling_convention(function_type);
x86_cconv_t *cconv = XMALLOCZ(x86_cconv_t);
cconv->sp_delta = (cc & cc_compound_ret) && !(cc & cc_reg_param)
? IA32_REGISTER_SIZE : 0;
cconv->parameters = params;
cconv->n_parameters = n_params;
cconv->callframe_size = stack_offset;
cconv->n_param_regs = n_param_regs_used;
cconv->n_xmm_regs = float_param_regnum;
cconv->results = results;
cconv->omit_fp = omit_fp;
cconv->caller_saves = caller_saves;
cconv->callee_saves = callee_saves;
cconv->n_reg_results = n_reg_results;
if (irg != NULL) {
be_irg_t *birg = be_birg_from_irg(irg);
size_t n_ignores = ARRAY_SIZE(ignore_regs);
struct obstack *obst = &birg->obst;
birg->allocatable_regs = rbitset_obstack_alloc(obst, N_IA32_REGISTERS);
rbitset_set_all(birg->allocatable_regs, N_IA32_REGISTERS);
for (size_t r = 0; r < n_ignores; ++r) {
rbitset_clear(birg->allocatable_regs, ignore_regs[r]);
}
if (!omit_fp)
rbitset_clear(birg->allocatable_regs, REG_EBP);
}
return cconv;
}
