// TODO: Return the value or store it?
llvm::Value*
Generator::gen(Default_init const* e)
{
Type const* t = e->type();
llvm::Type* type = get_type(t);
// Scalar types should get a 0 value in the
// appropriate type.
if (is_scalar_type(t))
return llvm::ConstantInt::get(type, 0);
// Aggregate types are zero initialized.
//
// NOTE: This isn't actually correct. Aggregate types
// should be memberwise default initialized.
if (is_aggregate_type(t))
return llvm::ConstantAggregateZero::get(type);
throw std::runtime_error("unhahndled default initializer");
}
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;
}
