id	summary	reporter	owner	description	type	status	priority	component	version	resolution	keywords	cc	blockedby	blocking	reproduced	analyzed
510	Android internal compiler error on qcelpdec.c when NEON is used	dmitrykos		"Android compiler (gcc version 4.4.3 (GCC)) is failing (internal compiler) to compile qcelpdec.c if NEON is enabled as fpu.

Error happens for this function 'qcelp_decode_frame' but tracking the roots of problem I arrived to 'postfilter' function:

this loop is causing failure:

{{{
for (n = 0; n < 10; n++) {
    lpc_s[n] = lpc[n] * pow_0_625[n];
    lpc_p[n] = lpc[n] * pow_0_775[n];
}
}}}

to resolve the problem I tried to unroll it and compiler error is gone:

{{{
#define QCELP_POSTFILTER_LPC__MPOW(N)\
	lpc_s[(N)] = lpc[(N)] * pow_0_625[(N)];\
	lpc_p[(N)] = lpc[(N)] * pow_0_775[(N)]

    QCELP_POSTFILTER_LPC__MPOW(0);
    QCELP_POSTFILTER_LPC__MPOW(1);
    QCELP_POSTFILTER_LPC__MPOW(2);
    QCELP_POSTFILTER_LPC__MPOW(3);
    QCELP_POSTFILTER_LPC__MPOW(4);
    QCELP_POSTFILTER_LPC__MPOW(5);
    QCELP_POSTFILTER_LPC__MPOW(6);
    QCELP_POSTFILTER_LPC__MPOW(7);
    QCELP_POSTFILTER_LPC__MPOW(8);
    QCELP_POSTFILTER_LPC__MPOW(9);
	
#undef QCELP_POSTFILTER_LPC__MPOW
}}}

Most probably it happens due to error in NEON vectoriser and thus unrolling helps."	defect	closed	normal	avcodec	git-master	wontfix					0	0