13.7.21. SYS_HEAPINFO (0x16)

Returns the system heap parameters. The values returned are typically those used by the Angel C library during initialization. These values are defined in the devconf.h header file. Refer to Modifying target-specific files for a description of devconf.h.

The C library can override these values, but will do so only if __heap_base is defined at link time. In this case the values of the following symbols are used:

This call returns sensible answers if EmbeddedICE is being used, but the values are determined by the host debugger using the $top_of_memory debugger variable.

Entry

On entry, r1 points to a single word data block:

word 1

is the address at which the heap descriptor is located.

Return

On exit, r1 points to a single word data block:

word 1

is the address at which the heap descriptor is located.

The heap descriptor is a block of four words of data that contains the stack and heap base and limit:

word 1

Heap Base.

word 2

Heap Limit.

word 3

Stack Base.

word 4

Stack Limit.

Copyright © 1997, 1998 ARM Limited. All rights reserved.ARM DUI 0040D
Non-Confidential