Calling convention

=== x86 (32-bit) ===

=== x86 (32-bit) ===

{{Main|x86 calling conventions}}

{{Main|x86 calling conventions}}

The 32-bit version of the [[x86 architecture]] is used with many different calling conventions. Due to the small number of architectural registers, and historical focus on simplicity and small code-size, many x86 calling conventions pass arguments on the stack. The return value (or a pointer to it) is returned in a register. Some conventions use registers for the first few parameters which may improve performance, especially for short and simple leaf-routines very frequently invoked (i.e. routines that do not call other routines).

The 32-bit version of the [[x86 architecture]] is used with many different calling conventions. Due to the small number of architectural registers, and historical focus on simplicity and small code-size, many x86 calling conventions pass arguments on the stack. The return value (or a pointer to it) is returned in a register. Some conventions use registers for the first few parameters which may improve performance, especially for short and simple [[leaf subroutine|leaf-routine]]s very frequently invoked (i.e. routines that do not call other routines).

Example call:

Example call: