[asterisk-dev] Building codec_gsm against Spandsp

[Michael Keuter]

>  On 7/21/10 2:20 PM, Philip Prindeville wrote:
>>    On 7/21/10 11:34 AM, Philip Prindeville wrote:
>>>     On 2/3/10 6:52 PM, Steve Underwood wrote:
>>>>On 02/04/2010 08:17 AM, Tzafrir Cohen wrote:
>>>>>On Wed, Feb 03, 2010 at 03:53:00PM -0800, Philip A. Prindeville wrote:
>>>>>
>>>>>>Does anyone have patches (or otherwise know what would be involved) to
>>>>>>build Asterisk's codec_gsm against the Spandsp library?
>>>>>>
>>>>>Why would you want that?
>>>>>
>>>>The libgsm with some distributions is quite slow, and some won't pass
>>>>the test vectors, so there are good reasons to choose an alternative. I
>>>>think the Asterisk one actually fails a couple of the test vectors, but
>>>>its close to correct.
>>>>>libgsm is a separate library. Most distributions include it nowadays.
>>>>>Asterisk can either use its internal copy or the system copy of it.
>>>>>
>>>>I know people were in denial for ages, blaming GCC for being faulty, but
>>>>I thought the GSM codec in the Asterisk was eventually fixed. The
>>>>problem is just an error in embedded assembly language code, where the
>>>>better optimiser in GCC 4.2 made there error show up for the first time.
>>>Do you remember what the bug # was?  We need to reopen this bug... 
>>>At the very least, it can't be too difficult to through in a 
>>>pragma to cause GCC to not optimize and rewrite the code, yes?
>>>
>>>BTW:  I still like the idea of patching Asterisk to allow it to 
>>>build --with-spandsp much more.
>>>
>>>-Philip
>>Looking at trunk/codecs/gsm/Makefile, I see:
>>
>># add k6-specific code only if not on a non-k6 hardware or proc.
>># XXX Keep a space after each findstring argument
>># XXX should merge with GSM_OBJECTS
>>ifeq ($(OSARCH),linux-gnu)
>>ifeq (,$(findstring $(shell uname -m) , x86_64 amd64 ppc ppc64 
>>alpha armv4l sparc64 parisc s390 ))
>>ifeq (,$(findstring $(PROC) , arm armv5b armeb powerpc ia64 s390 
>>bfin mipsel mips ))
>>GSM_SOURCES+= $(SRC)/k6opt.s
>>endif
>>endif
>>endif
>>
>>
>>This is non-good.  It's assuming that the machine the compile is 
>>being done on is the same as the machine the generated object will 
>>run on.
>>
>>-Philip
>>
>
>I borrowed one of the patches from 11243 and tweaked it a little.  Attaching.
>
>We might need to reopen this bug.  Qwell committed the private.h asm 
>patch, but as Coppice pointed out that may not have been enough.
>
>-Philip

This tweaked patch works now fine for me. The distortion of GSM 
sounds is now gone.
Thanks.

Michael

http://www.mksolutions.info