There are several issues with the Clang compiler and pixman-mmx.c:
- When not optimizing, it doesn't seem to recognize that an argument
to an __always_inline__ function is compile-time constant. This
results in this error being produced:
fatal error: error in backend: Invalid operand for inline asm
constraint 'K'!
- This inline assembly:
asm ("pmulhuw %1, %0\n\t"
: "+y" (__A)
: "y" (__B)
);
results in
fatal error: error in backend: Unsupported asm: input constraint
with a matching output constraint of incompatible type!
So disable MMX when the compiler is Clang.
Allows you to compile without -flax-vector-conversions in your CFLAGS,
though -march=iwmmxt2 is still necessary since specifying some other
-march= value will override it, and disable iwmmxt.
Signed-off-by: Matt Turner <mattst88@gmail.com>
iwMMXt is incorrectly detected on x86 and amd64. This happens because
the test uses standard _mm_* intrinsic functions which it compiles with
-march=iwmmxt, but when the user has set CFLAGS=-march=k8 for instance,
no error is generated from -march=iwmmxt, even though it's not a valid
flag on x86/amd64. Passing CFLAGS=-march=native does not override the
-march=iwmmxt flag though, which is why it wasn't noticed before.
So, just #error out in the test if the __arm__ preprocessor directive
isn't defined.
Fixes https://bugs.gentoo.org/show_bug.cgi?id=385179
Signed-off-by: Matt Turner <mattst88@gmail.com>
Check in configure for at least gcc-4.6, since gcc-4.7 (and hopefully
4.6) will be the eariest version capable of compiling the _mm_*
intrinsics on ARM/iwmmxt. Even for suitable compile versions I use
_mm_srli_si64 which is known to cause unpatched compilers to fail.
Select iwmmxt at runtime only after NEON, since we expect the NEON
optimizations to be more capable and faster than iwmmxt.
Signed-off-by: Matt Turner <mattst88@gmail.com>
When debugging it is often very useful to be able to save an image as
a png file. This commit adds a function "write_png()" that does that.
If libpng is not available, then the function becomes a noop.
Autoconf 2.86 reports:
warning: AC_LANG_CONFTEST: no AC_LANG_SOURCE call detected in body
Every code fragment must be wrapped in [AC_LANG_SOURCE([...])]
PIXMAN_LINK_WITH_ENV did not fail unless -Wall -Werror is used.
So even when the compiler did not support OpenMP, USE_OPENMP was defined.
Fix that by running the second OpenMP test only when first AC_OPENMP find supported
configure tested in the cases :
gcc without libgomp support, no openmp option, --enable-openmp and --disable-openmp
gcc with libgomp support, no openmp option, --enable-openmp and --disable-openmp
Not tested with autoconf version not knowing openmp (<2.62)
Warn when --enable-openmp is requested but no support is found
Signed-off-by: Gilles Espinasse <g.esp@free.fr>
This separates the test suite from the random gtk+ using test
programs. "demos" is somewhat misleading because the programs there
are not particularly exciting (with the possible exception of
composite-test which shows off all the compositing operators).
It seems to be relatively common for people to use development
snapshots of pixman thinking they are ordinary releases. This patch
makes it such that if the current minor version is odd, configure will
print a banner explaining the version number scheme plus information
about where to report bugs.
This option can be used for building fully static binaries of the test
programs so that they can be easily run using qemu-user. With binfmt-misc
configured, 'make check' works fine for crosscompiled pixman builds.
There is attribute 'constructor' supported since gcc 2.7 which allows
to have a constructor function for library initialization. This eliminates
an extra branch for each composite operation and also helps to avoid
complains from race condition detection tools like helgrind.
The other compilers may or may not support this attribute properly.
Ideally, the compilers should fail to compile the code with unknown
attribute, so the configure check should do the right job. But in
reality the problems are surely possible. Fortunately such problems
should be quite easy to find because NULL pointer dereference should
happen almost immediately if the constructor fails to run.
clang 2.7:
supports __attribute__((constructor)) properly and pretends to be gcc
tcc 0.9.25:
ignores __attribute__((constructor)), but does not pretend to be gcc
