This file is built on its own from within the xcode projects,
even though it isn't necessary. Previously its contents was just
empty, but now a .syntax unified was added, which failed the build
when building for arm64.
Make this file a no-op, just like the other arm assembly source files,
unless HAVE_NEON is defined.
If kiCpuCores < 2, then iCountThreadsNum (and iMultipleThreadIdc)
can't be >= 2, because they're initialized with
WELS_MIN (kiCpuCores, ...) just a few lines above.
If iMultipleThreadIdc is initially set to 0 by the caller, this
removed piece of code would change it to 1, if kiCpuCores < 2.
When iMultipleThreadIdc is changed from the originally set value,
a call to WelsEncoderParamAdjust with the original parameters
would reset the whole codec since iMultipleThreadIdc differs.
This fixes running EncoderInterfaceTest.TemporalLayerSettingTest
on machines where the detected number of cores is 1.
This is the default when building with the clang built-in assembler,
but not if using the external assembler - thus always specify it,
for clarity.
Also use the three-operand for of a sub instruction in BS_NZC_CHECK.
The same is already done in the gnu version of the macro.
This fixes building most of the arm assembly with Apple's external
assembler. While this isn't a necessary goal in itself, there's no
harm in doing this either.
Interpreting data of one type via a pointer of a different type is an
aliasing violating. This means that a compiler optimizer's analyzer
can assume that data loaded into an array as uint32_t isn't related
to data read out from the same array as uint64_t, and e.g. reorder
loads/stores.
Since these structs are intentionally used to load data via pointers
of a wrong size, tell the compiler that these accesses may alias
other reads.
This fixes the GetIntraPredictorTest tests of WelsI4x4LumaPredV_c
and WelsI4x4LumaPredH_c. (The compiler optimizer did the wrong thing
as long as WelsFillingPred8to16_c or WelsFillingPred8x2to16_c were
inlined into the calling function.)
