[FFmpeg-devel] compile for arm cortex A8 with iOS SDK 5

gary neve_capricorn at gmx.de
Mon Jan 9 21:08:52 CET 2012


iam using ffmpeg-HEAD-f247f4c with llvm-gcc.4.2 compiler. 

when i activate the ASM neon support iam hanging right now at some instructions.

i tried a first fix in the libavutil.h

intmath.h

#define av_clipl_int32 av_clipl_int32_arm
static av_always_inline av_const int32_t av_clipl_int32_arm(int64_t a)
{
    int x, y;
    __asm__ (//"adds   %1, %R2, %Q2, lsr #31  \n\t"
             "itet   ne                     \n\t"
             "mvnne  %1, #1<<31             \n\t"
             //"moveq  %0, %Q2                \n\t"
             //"eorne  %0, %1,  %R2, asr #31  \n\t"
             : "=r"(x), "=&r"(y) : "r"(a):"cc");
    return x;
}

now i have another problem in 
CC	libavformat/asf.o
CC	libavformat/asfcrypt.o
error: invalid operand in inline asm: 'ldr   ${0:Q}, $1  
	ldr   ${0:R}, $2  
	'

but i cant find the right ASM function for this problem.

compiling line was:
./configure \
--target-os=darwin \
--cc=/Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-gcc-4.2  \
--as="gas-preprocessor.pl /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/llvm-gcc-4.2" \
--sysroot=/Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.0.sdk \
--extra-cflags="-w -arch armv7 -mfpu=neon " \
--extra-ldflags="-arch armv7 -mfpu=neon -isysroot /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS5.0.sdk" \
--arch=arm \
--cpu=cortex-a8 \
--extra-cflags='-arch armv7' \
--extra-ldflags='-arch armv7' \
--prefix=compiled/armv7 \
--disable-ffmpeg \
--disable-ffplay \
--disable-ffprobe \
--disable-ffserver \
--disable-avdevice \
--disable-bzlib \
--disable-mmx \
--disable-encoders \
--enable-cross-compile \
--enable-pic
make

Anyone can help me, maybe with paid support?

gary




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