Datasheet

The C and C++ Libraries
ARM DUI 0067D Copyright © 1999-2001 ARM Limited. All rights reserved. 4-71
Syntax
__value_in_regs struct __heap_extent __user_heap_extent(unsigned ignore1,
unsigned ignore2)
Implementation
There is no default implementation of this function. The valuesof the parameters
ignore1 and ignore2 are not used by the function.
4.9.7 __user_stack_slop()
If defined, this function returns the size of the extra stack your system requires below
sl. The extra stack is in addition to the 256 bytes required by ATPCS. The extra space
might enable an interrupt handler to execute on your stack or enable a chain of
unchecked functions calls.
Syntax
__stack_slop__user_stack_slop(unsignedignore, unsignedignore)
Implementation
There is no default implementation of this function.
Returns
If you define this function, it must return the following values in registers:
r0 The amount of extra stack (measured in bytes) that must always be
available so an interrupt handler can execute on the stack at an arbitrary
instant.
r1 The amount of extra stack (measured in bytes) that must be available after
stack overflow to support recovery from overflow.
4.9.8 __rt_stackheap_init()
This function is responsible for setting up sp and sl to point at a valid stack, and must
also return in r0 and r1 the lower and upper bounds of a chunk of memory that can be
used as a heap. (It can decline to do the latter, by returning r0 equal to r1. In this case,
the first call to
malloc() results in a call to __rt_heap_extend() , described in
__rt_heap_extend() on page 4-73.) An incomplete prototype implementation is in
rt_memory.s . Because it is the first function called from entry, it does not have to