configure

#!/bin/sh
# Anticonf (tm, Jeroen Ooms) style alternative to autoconf written by Louis
# Aslett based on work by Jeroen Ooms (cf github: jeroen/curl & jeroen/openssl)

PKG_CONFIG_NAME="zlib"
PKG_DEB_NAME="zlib1g-dev"
PKG_RPM_NAME="zlib-devel"
PKG_CSW_NAME="libz_dev"
PKG_TEST_HEADER="<zlib.h>"
PKG_LIBS="-lz $PKG_LIBS"
PKG_CFLAGS="$PKG_CFLAGS"

# Try using pkg-config if it exists
pkg-config --version >/dev/null 2>&1
if [ $? -eq 0 ]; then
  PKGCONFIG_CFLAGS=`pkg-config --cflags ${PKG_CONFIG_NAME}`
  PKGCONFIG_LIBS=`pkg-config --libs ${PKG_CONFIG_NAME}`
fi

# Include and library directories
if [ "$INCLUDE_DIR" ] || [ "$LIB_DIR" ]; then
  echo "Found INCLUDE_DIR and/or LIB_DIR!"
  PKG_CFLAGS="-I$INCLUDE_DIR $PKG_CFLAGS"
  PKG_LIBS="-L$LIB_DIR $PKG_LIBS"
elif [ "$PKGCONFIG_CFLAGS" ] || [ "$PKGCONFIG_LIBS" ]; then
  echo "Found pkg-config cflags and libs!"
  PKG_CFLAGS="$PKGCONFIG_CFLAGS $PKG_CFLAGS"
  PKG_LIBS="$PKGCONFIG_LIBS $PKG_LIBS"
fi

# Find compiler
CC=`${R_HOME}/bin/R CMD config CC`
CFLAGS=`${R_HOME}/bin/R CMD config CFLAGS`

# Debug info
echo "Using PKG_CFLAGS=$PKG_CFLAGS"
echo "Using PKG_LIBS=$PKG_LIBS"

# Test configuration
echo "#include $PKG_TEST_HEADER" | ${CC} ${PKG_CFLAGS} ${CFLAGS} -Wno-error -E -xc - >/dev/null 2>&1 || R_CONFIG_ERROR=1;

# Customize the error
if [ $R_CONFIG_ERROR ]; then
  echo "------------------------- ANTICONF ERROR ---------------------------"
  echo "Configuration failed because $PKG_CONFIG_NAME was not found. Try installing:"
  echo " * deb: $PKG_DEB_NAME (Debian, Ubuntu, etc)"
  echo " * rpm: $PKG_RPM_NAME (Fedora, CentOS, RHEL)"
  echo " * csw: $PKG_CSW_NAME (Solaris)"
  echo "If $PKG_CONFIG_NAME is already installed, check that 'pkg-config' is in your"
  echo "PATH and PKG_CONFIG_PATH contains a $PKG_CONFIG_NAME.pc file. If pkg-config"
  echo "is unavailable you can set INCLUDE_DIR and LIB_DIR manually via:"
  echo "R CMD INSTALL --configure-vars='INCLUDE_DIR=... LIB_DIR=...'"
  echo "--------------------------------------------------------------------"
  exit 1;
fi

# Check combinations of intrinsics flags
counter=0
intrinsics=""
[ -n "${NOASM+isset}" ] && counter=$((counter + 1)) && PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_NOASM" && intrinsics="No special assembly"
[ -n "${AVX512+isset}" ] && counter=$((counter + 1)) && PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_AVX512" && intrinsics="AVX-512 family of"
[ -n "${AVX2+isset}" ] && counter=$((counter + 1)) && PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_AVX2" && intrinsics="AVX2 family of"
[ -n "${NEON+isset}" ] && counter=$((counter + 1)) && PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_NEON" && intrinsics="NEON family of"
# Were zero/one options chosen?
if [ "$counter" -gt 1 ]; then
  echo "ERROR: At most one set of instructions can be specified (NOASM, AVX512, AVX2 or NEON)"
  exit 1
fi
# Was an option forced?
if [ "$counter" -eq 1 ]; then
  echo "$intrinsics instruction set extentions will by used (forced by user)."
fi
# If no option force by user, then attempt to auto-detect
if [ "$counter" -eq 0 ]; then

  intrindetected=0

  # Check if we're on an x86 system with AVX-512 family ISA
  intrin=0
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__AVX512F__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__AVX2__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__SSE2__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__BMI2__" > /dev/null
  intrin=$((intrin+$?))
  echo "#include <immintrin.h>" | ${CC} ${PKG_CFLAGS} ${CFLAGS} -Wno-error -E -xc - >/dev/null 2>&1
  intrin=$((intrin+$?))
  if [ "$intrindetected" -eq 0 ] && [ "$intrin" -eq 0 ]; then
    PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_AVX512"
    intrinsics="AVX-512 family of"
    intrindetected=1
  fi

  # Check if we're on an x86 system with AVX2 family ISA
  intrin=0
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__AVX2__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__AVX__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__SSE4_1__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__SSE2__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__FMA__" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__BMI2__" > /dev/null
  intrin=$((intrin+$?))
  echo "#include <immintrin.h>" | ${CC} ${PKG_CFLAGS} ${CFLAGS} -Wno-error -E -xc - >/dev/null 2>&1
  intrin=$((intrin+$?))
  if [ "$intrindetected" -eq 0 ] && [ "$intrin" -eq 0 ]; then
    PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_AVX2"
    intrinsics="AVX2 family of"
    intrindetected=1
  fi

  # Check if we're on an ARM system with NEON intrinsics
  intrin=0
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__ARM_NEON" > /dev/null
  intrin=$((intrin+$?))
  ${CC} ${PKG_CFLAGS} ${CFLAGS} -dM -E - < /dev/null | grep "__ARM_FEATURE_FMA" > /dev/null
  intrin=$((intrin+$?))
  echo "#include <arm_neon.h>" | ${CC} ${PKG_CFLAGS} ${CFLAGS} -Wno-error -E -xc - >/dev/null 2>&1
  intrin=$((intrin+$?))
  if [ "$intrindetected" -eq 0 ] && [ "$intrin" -eq 0 ]; then
    PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_NEON"
    intrinsics="NEON family of"
    intrindetected=1
  fi

  if [ "$intrindetected" -eq 0 ]; then
    PKG_CFLAGS="$PKG_CFLAGS -DKALIS_ISA_NOASM"
    intrinsics="No special assembly"
  fi

  echo "$intrinsics instruction set extentions will by used (auto-detected)."
fi

# Check if we have access to pthreads (checking functions and headers, so no -E on compiler)
echo "#define _GNU_SOURCE
#include <pthread.h>
int main() {
  pthread_t threads[2];
  pthread_attr_t attr;
  pthread_attr_init(&attr);
  pthread_create(&threads[0], &attr, NULL, NULL);
  return 0;
}" | ${CC} ${PKG_CFLAGS} ${CFLAGS} -Wno-error -pthread -xc - >/dev/null 2>&1
if [ "$?" -eq 0 ]; then
  PKG_CFLAGS="$PKG_CFLAGS -pthread"
  PKG_LIBS="$PKG_LIBS -lpthread -pthread"
  echo "Threading support detected."
fi
# NB: MacOS has pthreads but not pthread_setaffinity_np
echo "#define _GNU_SOURCE
#include <pthread.h>
int main() {
  cpu_set_t cpus;
  CPU_ZERO(&cpus);
  CPU_SET(1, &cpus);
  pthread_setaffinity_np(0,0,0);
  return 0;
}" | ${CC} ${PKG_CFLAGS} ${CFLAGS} -Wno-error -pthread -xc - >/dev/null 2>&1
if [ "$?" -eq 0 ]; then
  PKG_CFLAGS="$PKG_CFLAGS -DKALIS_AFFINITY"
  echo "Thread affinity support detected."
fi

# To customise unroll depth
if [ ! -z ${UNROLL+isset} ]; then
  PKG_CFLAGS="$PKG_CFLAGS -DKALIS_UNROLL=$UNROLL"
  echo "Loop unrolling default overridden by UNROLL configure-vars flag to depth $UNROLL"
else
  echo "Loop unrolling at default value"
fi

# Gen Makevars
sed -e "s|@cflags@|$PKG_CFLAGS|" -e "s|@libs@|$PKG_LIBS|" src/Makevars.in > src/Makevars

if [ -f a.out ] ; then
    rm a.out
fi
if [ -e a.out.dSYM ] ; then
    rm -rf a.out.dSYM
fi

# Success
exit 0