User:Hef/ispc on rpi2

setup

gcc 4.6 both won't compile latest llvm/clang and will generate an ICE on older versions of clang.

<syntaxHighlight lang=bash> sudo apt-get install cmake gcc-4.8 g++-4.8 bison flex libncurses5-dev subversion </syntaxHighlight>

second attempt

<syntaxHighlight lang=bash> export LLVM_HOME=~/projects/llvm_home export ISPC_HOME=$PWD export CC=/usr/bin/gcc-4.8 export CXX=/usr/bin/g++-4.8 export CFLAGS="-march=armv7-a -mtune=cortex-a7 -mfpu=neon-vfpv4" export CXXFLAGS="-march=armv7-a -mtune=cortex-a7 -mfpu=neon-vfpv4" ./alloy.py -b --version=3.5 export PATH=$PATH:$LLVM_HOME/bin-3.5/bin

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I should try adding export CFLAGS="-march=armv7-a -mtune=cortex-a7 -mfpu=neon-vfpv4"

first attempt

ninja

<syntaxHighlight lang=bash> git clone git://github.com/martine/ninja.git cd ninja git checkout release ./configure.py --bootstrap sudo cp ninja /usr/local/bin/ninja </syntaxHighlight>

clang

<syntaxHighlight lang=bash> git clone http://llvm.org/git/llvm.git cd llvm/tools git clone http://llvm.org/git/clang.git cd ../../.. mkdir llvm-build cd llvm-build cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=/usr/bin/gcc-4.8 -DCMAKE_CXX_COMPILER=/usr/bin/g++-4.8 ../llvm -G Ninja ninja -j1 </syntaxHighlight>

Ninja will take many hours to complete. I didn't fully test the -j (concurrent build) options to ninja. ninja defaults to 6 on the rpi2. You will run out of memory if you do this. Even if you create larger swap for the pi, swapping to an sd card is a really major performance hit and you will be better of using fewer cores.

self hosted clang

<syntaxHighlight lang=bash> cmake -DCMAKE_BUILD_TYPE=Release -DCMAKE_C_COMPILER=/usr/local/bin/clang -DCMAKE_CXX_COMPILER=/usr/local/bin/clang++ ../llvm -G Ninja </syntaxHighlight>

ispc

<syntaxHighlight lang=bash> make ARM_ENABLED=1 -j4 </syntaxHighlight>