Skip to content

ATLAS configure step

Jump to bottom Edit New page
Matthew Brett edited this page Feb 15, 2016 · 1 revision

Some notes on the configure step in ATLAS

Summary

  • ATLAS configure is not an autoconf configure script
  • It is a sh script that compiles and runs binaries from C code called probes. Configure therefore needs a working C compiler and a working make command.
  • The probes do most of the work of getting configuration values from the hardware.

After the configure step comes the build step.

Introduction

You'll find the main docs for configure at ATLAS configure step.

As you will see from these docs, the basic procedure is:

cd BLDdir ; SRCdir/configure [flags]

where BLDdir is an empty directory to contain the configuration and build files, and SRCdir is the path to the ATLAS source code.

Architecture overview

The first thing to remember is: ATLAS configure is not an autoconf configure command. ATLAS doesn't use autoconf at all.

See Clint's email on ATLAS configure / build for Clint Whaley's summary of configure. Some of that email appears in this document.

However, like autoconf configure, configure is a sh script. At the top of this script you will find the following comment:

# BFI configure-like script to bootstrap ATLAS's C-based config scripts
# dependencies: sed, pwd
# shell built-in deps: echo, test

The script compiles a bunch of C scripts and probes which are found in SRCdir/CONFIG.

The configure script:

  • Creates the universal Make.inc, which defines all Makefile macros for all of ATLAS's makefiles. In the case of new systems where things must be kludged, Make.inc allows the user to edit only one file, rather than the standard autoconf configure method of generating the individual makefiles, all of which have to be hand-edited in the case of problems.
  • Moves all needed Makefiles into BLDdir.
  • Probes the system using simple test routines (in CONFIG/) to figure out very detailed information (what ISA, what ISA extension/vector operation, what assembly dialect, what type of threading works, etc). Most of this probe info is reflected in the produced Make.inc.

The configure step is therefore analogous to the normal autoconf configure step, though ATLAS is looking for much more detailed information than a typical autoconf configuration run.

There is more detail on the architecture of ATLAS configure in information on atlconf.

Running ATLAS configure

There is some useful help on flags from:

SRCdir/configure --help

Note the double hyphen for --help.

Here's the output from SRCdir/configure --help:

ATLAS config includes this script, and probes written in C.
Therefore, configure flags are union of script and probe flags.
This configure script accepts the following flags:
--cc=<C compiler> : compiler to compile configure probes
--cflags='<flags>' : flags for above
--prefix=<dirname> : Toplevel installation directory.
                        Default: /usr/local/atlas
--incdir=<dirname> : Installation dir for include files
                        Default: /usr/local/atlas/include
--libdir=<dirname> : Installation dir for libraries
                        Default: /usr/local/atlas/lib
--rtarg=<mach> : remote cross-compile target machine
--accel=[0/1/2] : build for accelerator:
    0: Don't build for accelerator
    1: Build for TI_C66_BM
    2: Build for Xeon Phi
--shared : same as --dylibs
--dylibs : build dynamic/shared libs in addition to static libs
--force-tids="<#> threadIDlist"
--nof77 : You have no Fortran compiler installed.  Note that
            this will disallow building the F77 interface, and
            some of the tests (eg, standard BLAS testers)
--with-netlib-lapack-tarfile=<path to lapack tarfile>
--gcc3pass=<gcc for frontend>,<assembler>:<linker>
    Provide full paths for all compilers/assemblers
Attempting to build xconfig to get probe flags:
../ATLAS/configure: line 113: ./xconfig: No such file or directory

ATLAS tried to compile a file xconfig, but failed. We can get it to compile and run by passing a bad argument into configure, e.g. SRCdir/configure bad-arg. Then we get this:

gcc -I/Users/mb312/dev_trees/math-atlas/TEST/build_test/../ATLAS//CONFIG/include  -g -w -c /Users/mb312/dev_trees/math-atlas/TEST/build_test/../ATLAS//CONFIG/src/atlconf_misc.c
gcc -I/Users/mb312/dev_trees/math-atlas/TEST/build_test/../ATLAS//CONFIG/include  -g -w -o xconfig /Users/mb312/dev_trees/math-atlas/TEST/build_test/../ATLAS//CONFIG/src/config.c atlconf_misc.o 
./xconfig -d s /Users/mb312/dev_trees/math-atlas/TEST/build_test/../ATLAS/ -d b /Users/mb312/dev_trees/math-atlas/TEST/build_test  bad-arg

ERROR around arg 7 (bad-arg).
USAGE: ./xconfig [flags] where flags are:
-v <verb> : verbosity level
-O <enum OSTYPE #>  : set OS type
-s <enum ASMDIA #>  : set assembly dialect
-A <enum MACHTYPE #> : set machine/architecture
-V #    # = ((1<<vecISA1) | (1<<vecISA2) | ... | (1<<vecISAN))
-b <32/64> : set pointer bitwidth
-o <outfile>
-C [xc,ic,if,sk,dk,sm,dm,al,ac] <compiler>
-F [xc,ic,if,sk,dk,sm,dm,al,ac,gc] '<comp flags>'
-Fa [xc,ic,if,sk,dk,sm,dm,al,ac,gc] '<comp flags to append>'
        al: append flags to all compilers
        ac: append flags to all C compilers
        gc: append flags to gcc compiler used in user-contributed index files.
        acg: append to all C compilers & the index gcc
        alg: append to all compilers & the index gcc
-T <targ> : ssh target for cross-compilation (probably broken)
-D [c,f] -D<mac>=<rep> : cpp #define to add to [CDEFS,F2CDEFS]
    eg. -D c -DL2SIZE=8388604 -D f -DADD__ -D f -DStringSunStyle
-d [s,b]  : set source/build directory
-f <#> : size (in KB) to flush before timing
-t <#> : set # of threads (-1: autodect; 0: no threading)
-tl <#> <list> : set # of threads, use list of affinity IDs
-r <#>: set the number of floating point registers to #
-m <mhz> : set clock rate
-S[i/s] <handle> <val>  : special int/string arg
    -Si bozol1 <0/1> : supress/enable bozo L1 defaults
    -Si archdef <1/0> : enable/supress arch default use
    -Si ieee <1/0> : dis/allow optimizations that break IEEE FP standard
        (eg., NEON, 3DNow!)
    -Si latune <1/0> : do/don't tune F77 LAPACK routines
    -Si nof77 <0/1> : Have/don't have fortran compiler
    -Si nocygwin <0/1> : Do/don't depend on GPL cygwin library
                        (Windows compiler/cygwin install only)
    -Si omp <0/1> : don'tuse/use OpenMP for threading
    -Si antthr <0/1/2> : nobuild/build/use Antoine's code for threading
    -Si lapackref <0/1>: Netlib lapack is not/is unpacked
                        to $BLDdir/src/lapack/ref
    -Ss kern <path/to/comp> : use comp for all kernel compilers
    -Ss ADdir <path/to/archdefs> : Get archdefs frm custom path
    -Ss pmake <parallel make invocation (eg '$(MAKE) -j 4')>
    -Ss f77lib <path to f77 lib needed by C compiler>
    -Ss flapack <path to netlib lapack>: used to build full lapack lib
    -Ss [s,d]maflags 'flags'
NOTE: enum #s can be found by : make xprint_enums ; ./xprint_enums
xconfig exited with 7

This output tells us about another aspect of configure - which is configure needs a working C compiler. Configure compiles many small binaries, called "probes" which it will use to get configuration binaries. To do this, it uses make and a C compiler. By default the C compiler command is gcc, but you can change this with the --cc= input argument to configure.

Another thing we notice is that many arguments are integers which are enumerated values. We can get the integers we need by following the instructions above: make xprint_enums ; ./xprint_enums:

Architectural enums (Config's enum MACHTYPE):
    0 = 'UNKNOWN'
    1 = 'POWER3'
    2 = 'POWER4'
    3 = 'POWER5'
    4 = 'PPCG4'
    5 = 'PPCG5'
    6 = 'POWER6'
    7 = 'POWER7'
    8 = 'POWERe6500'
    9 = 'IBMz9'
    10 = 'IBMz10'
    11 = 'IBMz196'
    12 = 'x86x87'
    13 = 'x86SSE1'
    14 = 'x86SSE2'
    15 = 'x86SSE3'
    16 = 'P5'
    17 = 'P5MMX'
    18 = 'PPRO'
    19 = 'PII'
    20 = 'PIII'
    21 = 'PM'
    22 = 'CoreSolo'
    23 = 'CoreDuo'
    24 = 'Core2Solo'
    25 = 'Core2'
    26 = 'Corei1'
    27 = 'Corei2'
    28 = 'Corei3'
    29 = 'Atom'
    30 = 'P4'
    31 = 'P4E'
    32 = 'Efficeon'
    33 = 'K7'
    34 = 'HAMMER'
    35 = 'AMD64K10h'
    36 = 'AMDDOZER'
    37 = 'AMDDRIVER'
    38 = 'UNKNOWNx86'
    39 = 'IA64Itan'
    40 = 'IA64Itan2'
    41 = 'USI'
    42 = 'USII'
    43 = 'USIII'
    44 = 'USIV'
    45 = 'UST2'
    46 = 'UnknownUS'
    47 = 'MIPSR1xK'
    48 = 'MIPSICE9'
    49 = 'ARMv7'
    50 = 'TI_C66_BM'
    51 = 'XeonPHI'

Operating System enums (Config's enum OSTYPE):
    0 = 'UNKNOWN'
    1 = 'Linux'
    2 = 'SunOS'
    3 = 'SunOS4'
    4 = 'OSF1'
    5 = 'IRIX'
    6 = 'AIX'
    7 = 'Win9x'
    8 = 'WinNT'
    9 = 'Win64'
    10 = 'HPUX'
    11 = 'FreeBSD'
    12 = 'OSX'

Compiler integer defines:
    0 = 'ICC'
    1 = 'SMC'
    2 = 'DMC'
    3 = 'SKC'
    4 = 'DKC'
    5 = 'XCC'
    6 = 'GCC'
    7 = 'F77'


ISA extensions are combined by adding their values together (bitvector):
        none: 1
        VSX: 2
    AltiVec: 4
        AVXZ: 8
    AVXMAC: 16
    AVXFMA4: 32
        AVX: 64
        SSE3: 128
        SSE2: 256
        SSE1: 512
        3DNow: 1024
FPV3D2MACNEON: 2048
FPV3D16MACNEON: 4096
FPV3D32MAC: 8192
FPV3D16MAC: 16384

This is more on probes in ATLAS probe overview

Add a custom footer
Add a custom sidebar
Clone this wiki locally