dmd.argtypes_aarch64
Break down a D type into basic (register) types for the AArch64 ABI.
License
Source: argtypes_aarch64.d
Documentation: https://dlang.org/phobos/dmd_argtypes_aarch64.html
-
Declaration
TypeTuple
toArgTypes_aarch64
(Typet
);This breaks a type down into 'simpler' types that can be passed to a function in registers, and returned in registers. This is the implementation for the AAPCS64 ABI, based on https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst.
Parameters
Type
t
type to break down
Return Value
tuple of 1 type if
can be passed in registers; e.g., a static array for Homogeneous Floating-point/Vector Aggregates (HFVA). A tuple of zero length means the type cannot be passed/returned in registers.t
null
indicates avoid
. -
Declaration
bool
isHFVA
(Typet
, intmaxNumElements
= 4, Type*rewriteType
= null);A Homogeneous Floating-point/Vector Aggregate (HFA/HVA) is an ARM/AArch64 concept that consists of up to 4 elements of the same floating point/vector type. It is the aggregate final data layout that matters so structs, unions, static arrays and complex numbers can result in an HFVA.
Discussion
simple HFAs: struct F1 {float f;} struct D4 {double a,b,c,d;} interesting HFA: struct {F1[2] vals; float weight;}
If the type is an HFVA and
is specified, it is set to a corresponding static array type.rewriteType