XLC 16.1 for AIX xlclang/xlclang++ does not support __sync_val_compare_and_swap

[vsebe]

/opt/IBM/xlC/16.1.0/bin/xlclang++  -I. -I../../base -I../../structs -I../../stats -I../../include -I../../verbose -I../../../../gc_glue_java -I../../../../ot
i -I../../../../include -I../../../../gc_base -I../../../../gc_include -I../../../../gc_stats -I../../../../gc_structs -I../../../../gc_base -I../../../../in
clude -I../../../../oti -I../../../../nls -I../../../../gc_include -I../../../../gc_structs -I../../../../gc_stats -I../../../../gc_modron_standard -I../../.
./../gc_realtime -I../../../../gc_trace -I../../../../gc_vlhgc  -I../../../../include -I../../../include_core -I../../../nls -DPPC64 -D_XOPEN_SOURCE_EXTENDED
=1 -D_ALL_SOURCE -DRS6000 -DAIXPPC -D_LARGE_FILES -c  -s -q64 -qlanglvl=extended0x -qarch=ppc -qalias=noansi -qxflag=LTOL:LTOL0 -qsuppress=1506-1108 -O3 -qha
lt=w -g   -o VerboseHandlerOutputStandard.o VerboseHandlerOutputStandard.cpp
...
In file included from VerboseHandlerOutputStandard.cpp:28:
In file included from ../../stats/ConcurrentGCStats.hpp:31:
In file included from ../../base/AtomicOperations.hpp:31:
../../../include_core/AtomicSupport.hpp:458:10: error: 1540-2993 The builtin "__sync_val_compare_and_swap_8" is not supported.
                return __sync_val_compare_and_swap(address, oldValue, newValue);
                       ^
1 error generated.
Error while processing VerboseHandlerOutputStandard.cpp.

where:

• toolchain: xlc 16.1.1
• CC: xlclang
• CXX: xlclang++

[vsebe]

@charliegracie fyi

[DanHeidinga]

@vsebe Is there a machine with xlc 16.1 that can be used for testing?

I think moving the XLC-specific code before the GCC-specific code may fix this issue.

xlc specific code:
https://github.com/eclipse/omr/blob/f96391d391659aec08ea33a623a7e3e3baf79235/include_core/AtomicSupport.hpp#L473-L475

gcc specific code:
https://github.com/eclipse/omr/blob/f96391d391659aec08ea33a623a7e3e3baf79235/include_core/AtomicSupport.hpp#L456-L458

[vsebe]

@DanHeidinga - XL/C 16 is installed on internal Jenkins machines (for now).

[DanHeidinga]

@vsebe I've opened #3887 to test the proposed change. Can you validate this on internal machines?

[vsebe]

@DanHeidinga - #3887 does not fix the issue

10:49:32  In file included from CompactScheme.cpp:27:
10:49:32  In file included from ./CompactScheme.hpp:33:
10:49:32  In file included from ./EnvironmentStandard.hpp:36:
10:49:32  In file included from ../../base/EnvironmentBase.hpp:35:
10:49:32  In file included from ../../../../gc_glue_java/EnvironmentDelegate.hpp:29:
10:49:32  In file included from ../../../../gc_stats/MarkJavaStats.hpp:31:
10:49:32  In file included from ../../base/AtomicOperations.hpp:31:
10:49:32  ../../../include_core/AtomicSupport.hpp:464:10: error: 1540-2993 The builtin "__sync_val_compare_and_swap_8" is not supported.
10:49:32                  return __sync_val_compare_and_swap(address, oldValue, newValue);

[DanHeidinga]

There's an xlc option required as well - I thought I pasted it here but the comment seems to have been lost. Looking...

[DanHeidinga]

-qxlcompatmacros https://www.ibm.com/support/knowledgecenter/SSGH3R_16.1.0/com.ibm.xlcpp161.aix.doc/compiler_ref/opt_qxlcompatmacros.html

[vsebe]

I added -qxlcompatmacros, rebuilt. New error:

12:45:33  In file included from ./AtomicOperations.hpp:31:
12:45:33  ../../include_core/AtomicSupport.hpp:112:29: error: use of undeclared identifier '__ppc_dropSMT'; did you mean '__dropSMT'?
12:45:33                  inline void __dropSMT() { __ppc_dropSMT(); }
12:45:33                                            ^~~~~~~~~~~~~
12:45:33                                            __dropSMT

xlclang/xlclang++ does not support legacy XL pragmas