ESP8266 Developer Zone

Re: math functions

2017-07-13T20:12:44+08:00

That should be:

.irom0.text : ALIGN(4)
{
_irom0_text_start = ABSOLUTE(.);

*libm.a:(.literal .text .literal.* .text.*)
....

works for me.

Statistics: Posted by Nikolay — Thu Jul 13, 2017 8:12 pm

Re: math functions

2015-07-20T23:42:09+08:00

Thanks, I already have libm.a I compiled toolchain myself, I even tried the one you shared. But the problem is iram0 section getting overflowed > 0x8000 Which is the limit of ESP8266. I think simply compiling libm with application does not solve the problem. So I change the question... Is it possible to link libm.a symbols to irom0 section whereas rest of the section as it is.

I tried changing linker but nothing worked. I moved irom0.text to before .text section and added following:

Code:

 .irom0.text : ALIGN(4)
  {
    _irom0_text_start = ABSOLUTE(.);
    *(.irom0.literal .irom.literal .irom.text.literal .irom0.text .irom.text)
    *(libm.a)
    *(libc.a)
    *(libgcc.a)
    _irom0_text_end = ABSOLUTE(.);
  } >irom0_0_seg :irom0_0_phdr

This does work and move all the symbols from .text to irom0 but application does not work at all.

I then tried:

Code:

 .irom0.text : ALIGN(4)
  {
    _irom0_text_start = ABSOLUTE(.);
    *(.irom0.literal .irom.literal .irom.text.literal .irom0.text .irom.text)
    libm.a: *(.literal .text)
    _irom0_text_end = ABSOLUTE(.);
  } >irom0_0_seg :irom0_0_phdr

this did not work either.. so any suggestion to move libm to rom section??? anyone from Espressif team?

Regards,
Ajay

Statistics: Posted by ajay.bhargav — Mon Jul 20, 2015 11:42 pm

Re: math functions

2015-07-20T17:27:20+08:00

Could this help ？ http://bbs.espressif.com/viewtopic.php?f=7&t=642&p=2403&hilit=math#p2409

Compile error ：http://bbs.espressif.com/viewtopic.php?f=10&t=166

Statistics: Posted by Her Mary — Mon Jul 20, 2015 5:27 pm

math functions

2015-07-18T05:23:53+08:00

Hi I need to use some math functions in my project but libm is not part of precompiled toolchain provided. So I compiled fresh toolchain from crosstool-NG available at github: https://github.com/jcmvbkbc/crosstool-NG I checked out branch lx106-g++. Toolchain compiled successfully. I can compile with libm now but... the linker reports error coz .text size has now increased > 0x8000

Code:

/opt/xtensa-lx106-elf/bin/../lib/gcc/xtensa-lx106-elf/4.8.2/../../../../xtensa-lx106-elf/bin/ld: .output/eagle/debug/image/eagle.app.v6.out section `.text' will not fit in region `iram1_0_seg'

I would like to know how can I use math functions? Are they available for ESP or not?

Statistics: Posted by ajay.bhargav — Sat Jul 18, 2015 5:23 am