Datasheet

Semihosting

5.4.20 SYS_HEAPINFO (0x16)

Returns the system stack and heap parameters. The values returned are typically those

used by the C library during initialization. For ARMulator, the values returned are the

those provided in

peripherals.ami

. For Multi-ICE, the values returned are the image

location and the top of memory.

The C library can override these values (see ADS Compilers and Libraries Guide for

more information on memory management in the C library).

The host debugger determines the actual values to return by using the

$top_of_memory

debugger variable.

Entry

On entry, r1 contains the address of a pointer to a four-word data block. The contents of

the data block are filled by the function. See Example 5-1 for the structure of the data

block and return values.

Example 5-1

struct block {

int heap_base;

int heap_limit;

int stack_base;

int stack_limit;

};

struct block *mem_block, info;

mem_block = &info;

AngelSWI(SYS_HEAPINFO, (unsigned) &mem_block);

Note

If word one of the data block has the value zero, the C library replaces the zero with

Image$$ZI$$Limit

. This value corresponds to the top of the data region in the memory

map.

Return

On exit, r1 contains the address of the pointer to the structure.

If one of the values in the structure is 0, the system was unable to calculate the real

value.