PHP_METHOD(Struct, getOffset) {
zval *zoffset;
php_jit_struct_t *pstruct;
zend_ulong of = 0;
if (php_jit_parameters("z", &zoffset) != SUCCESS || !zoffset) {
php_jit_exception("unexpected parameters, expected (string|integer field)");
return;
}
pstruct = PHP_JIT_FETCH_STRUCT(getThis());
switch (Z_TYPE_P(zoffset)) {
case IS_STRING:
if (!pstruct->names) {
php_jit_exception("no names available");
}
of = jit_type_find_name
(pstruct->type, Z_STRVAL_P(zoffset));
break;
case IS_LONG:
of = Z_LVAL_P(zoffset);
break;
default:
php_jit_exception("unexpected parameters, expected (string|integer field)");
return;
}
if (of < pstruct->nfields) {
RETURN_LONG(jit_type_get_offset(pstruct->type, of));
}
php_jit_exception("failed to find offset of requested field");
}
/*
* On X86_64 the alignment of native types matches their size.
* This leads to the result that all types except nfloats and aggregates
* (structs and unions) must start and end in an eightbyte (or the part
* we are looking at).
*/
static int
_jit_classify_structpart(jit_type_t struct_type, unsigned int start,
unsigned int start_offset, unsigned int end_offset)
{
int arg_class = X86_64_ARG_NO_CLASS;
unsigned int num_fields = jit_type_num_fields(struct_type);
unsigned int current_field;
for(current_field = 0; current_field < num_fields; ++current_field)
{
jit_nuint field_offset = jit_type_get_offset(struct_type,
current_field);
if(field_offset <= end_offset)
{
/* The field starts at a place that's inerresting for us */
jit_type_t field_type = jit_type_get_field(struct_type,
current_field);
jit_nuint field_size = jit_type_get_size(field_type);
if(field_offset + field_size > start_offset)
{
/* The field is at least partially in the part we are */
/* looking at */
int arg_class2 = X86_64_ARG_NO_CLASS;
if(is_struct_or_union(field_type))
{
/* We have to check this struct recursively */
unsigned int current_start;
unsigned int nested_struct_start;
unsigned int nested_struct_end;
current_start = start + start_offset;
if(field_offset < current_start)
{
nested_struct_start = current_start - field_offset;
}
else
{
nested_struct_start = 0;
}
if(field_offset + field_size - 1 > end_offset)
{
/* The struct ends beyond the part we are looking at */
nested_struct_end = field_offset + field_size -
(nested_struct_start + 1);
}
else
{
nested_struct_end = field_size - 1;
}
arg_class2 = _jit_classify_structpart(field_type,
start + field_offset,
nested_struct_start,
nested_struct_end);
}
else
{
if((start + start_offset) & (field_size - 1))
{
/* The field is misaligned */
return X86_64_ARG_MEMORY;
}
arg_class2 = _jit_classify_arg(field_type, 0);
}
if(arg_class == X86_64_ARG_NO_CLASS)
{
arg_class = arg_class2;
}
else if(arg_class != arg_class2)
{
if(arg_class == X86_64_ARG_MEMORY ||
arg_class2 == X86_64_ARG_MEMORY)
{
arg_class = X86_64_ARG_MEMORY;
}
else if(arg_class == X86_64_ARG_INTEGER ||
arg_class2 == X86_64_ARG_INTEGER)
{
arg_class = X86_64_ARG_INTEGER;
}
else if(arg_class == X86_64_ARG_X87 ||
arg_class2 == X86_64_ARG_X87)
{
arg_class = X86_64_ARG_MEMORY;
}
else
{
arg_class = X86_64_ARG_SSE;
}
}
}
}
}
return arg_class;
}
