Add heap stats for IAR

[deepikabhavnani]

Heap stats were not calculated for IAR, since we didn't have mechanism to hook IAR functions.

IAR has internal heap statistic data, which can be enabled and used. Below is the reference link
https://www.iar.com/support/tech-notes/general/iar-dlib-library-heap-usage-statistics/

Only current heap size (with 8 bytes of overhead per malloc) and max heap size is reported.
Below is the output for simple malloc program allocating and freeing 1000 bytes of memory

Allocating 1000 bytes
Current heap: 1008
Total heap size: 65536
Freeing 1000 bytes
Current heap after: 0
Total heap size: 65536

[YarivCol]

It will be nicer if we change dmalloc.c, add wrap function to malloc, free, etc...
In that case we will have full support to heap trace and heap stats.

[0xc0170]

It will be nicer if we change dmalloc.c, add wrap function to malloc, free, etc...
In that case we will have full support to heap trace and heap stats.

I believe this is not just for IAR, is it? To wrap all functions to enable trace/stats.
We used to have in dlmalloc with our own allocators ualloc (https://github.com/ARMmbed/ualloc)

[0xc0170]

Just in case, as the referenced page above is from 2015, this has no depedency on IAR 8? I would say no it does not.

@c1728p9 Please review

[deepikabhavnani]

This is just for IAR and not dependent on IAR 8.x version.

[deepikabhavnani]

@YarivCol - Yes it would be good to update dlmalloc.c and provide full support.

@sg- @bulislaw @0xc0170 @c1728p9 - Do we have any concerns in adding IAR code base file into mbed-os? dlmalloc.c code will be for only IAR support and we will have to re-visit this file everytime we upgrade to new IAR version, to make sure nothing breaks.

I compared dlmalloc.c in IAR7.8 and IAR 8.11 versions, and only change was an additional API added
dlaligned_alloc which is exact duplicate of existing aligment API dlmemalign. I don;t see any issues in porting for both IAR versions.

[sg-]

I dont think this is a file we should check in, rather ask IAR for a hook.

[TTornblom]

Isn't this something where one could use "$Super$$ and $Sub$$" (http://infocenter.arm.com/help/index.jsp?topic=/com.arm.doc.dui0377g/pge1362065967698.html) to hook into malloc()/free() etc?

Example:

#include <stdlib.h>
#include <stdio.h>

int main()
{
  int * p = (int *)malloc(100);
  int * p2 = (int *)malloc(100);
  p[2] = 45;
  free(p2);
  return p[3];
} 

extern void * $Super$$__iar_dlmalloc(size_t);

void * $Sub$$__iar_dlmalloc(size_t w)
{
  printf("Called with %d\n", w);
  return $Super$$__iar_dlmalloc(w);
}

[theotherjimmy]

@TTornblom Github uses ``` instead of --- for code comments, and you can get syntax highlighting if you specify the language after the first ```. For example ```C.

[TTornblom]

Thanks Jimmy, I noticed that the formatting was not good and tried wrapping it into the code quotes, but someone (you?) appeared to have fixed it already. Cheers, Thomas 15 sep. 2017 kl. 17:16 skrev Jimmy Brisson <notifications@github.com<mailto:notifications@github.com>>: @TTornblom<https://github.com/ttornblom> Github uses ``` instead of --- for code comments, and you can get syntax highlighting if you specify the language after the first ```C. - You are receiving this because you were mentioned. Reply to this email directly, view it on GitHub<#4965 (comment)>, or mute the thread<https://github.com/notifications/unsubscribe-auth/Ad-7pczfVqQ8Cn71F4Jvtyof3r00EBJ1ks5sipS3gaJpZM4PAfta>.

[theotherjimmy]

Oh, FYI @TTornblom, your suggestion will work for Arm Compiler {5|6}, and this PR is targeting IAR EWARM. I think they may have a similar wrapping feature, but your code snippet is not applicable to this PR. My mistake.

[TTornblom]

I work for IAR and this example was provided by IAR engineering, so works with IAR EWARM :)

[theotherjimmy]

@TTornblom Ah! My bad. Glad to have you in this discussion.

[deepikabhavnani]

@sg- @c1728p9 - Please review new implementation for heap stats as per suggestion from @TTornblom

[sg-]

do we need this lingering comment?

[deepikabhavnani]

@sg- Nah, just kept to have consistency.. Will remove

[c1728p9]

You might be able to combine the ARM and IAR code and just define the function names. Something like this:

#elif defined(TOOLCHAIN_ARM)
#define SUPER_MALLOC    $Super$$malloc
#define SUB_MALLOC      $Sub$$malloc
...

#elif defined(__ICCARM__)
#define SUPER_MALLOC    $Super$$__iar_dlmalloc
#define SUB_MALLOC      $Sub$$__iar_dlmalloc
...

#endif

extern "C" {
    void *SUPER_MALLOC(size_t);
    void *SUPER_REALLOC(void *ptr, size_t size);
    void *SUPER_CALLOC(size_t nmemb, size_t size);
    void SUPER_FREE(void *ptr);
}

extern "C" void *SUB_MALLOC(size_t size) {
    void *ptr = NULL;
...
}
...

[deepikabhavnani]

I intentionally separated IAR as was not sure if something additional would be required or not. Since its now working can merge ARM and IAR implementation

[deepikabhavnani]

/morph test

[mbed-bot]

Result: ABORTED

Your command has finished executing! Here's what you wrote!

/morph test

[deepikabhavnani]

/morph test

[mbed-bot]

Result: SUCCESS

Your command has finished executing! Here's what you wrote!

/morph test

Output

mbed Build Number: 1352

All builds and test passed!