[lldb] Skip tests using int128 on ARM

[werat]

Summary

Follow-up fix for https://reviews.llvm.org/D81471.

[jasonmolenda]

A very minor point but API tests don't need mydir = TestBase.compute_mydir(__file__) any more thanks to https://reviews.llvm.org/D128077 .

[labath]

I find the aarch64 part surprising, and it seems that the aarch64 bot did not have a problem with this patch (https://lab.llvm.org/buildbot/#/builders/96/builds/26089). The arm part is expected, and most likely applies to all 32 bit architectures (but I think we only have an arm bot at present).

[DavidSpickett]

(in case you aren't familiar when we say "Arm" we mean 32 bit Arm and AArch64 refers to 64 bit, it's not always that way but for this purpose it is)

I couldn't find a statement that AArch64 supports int128 but it will compile (https://godbolt.org/z/j5dqz4os4) and I ran the test locally without issue. Arm for sure doesn't support it.

Unless you saw a test failure on AArch64 as well I'd just disable for Arm. If you did please give me the link I'll see if there's some other aspect to this.

[werat]

I didn't see the test failure on AArch64, so you're both probably right. I've searched the code for other uses of int128 and found a similar place, which disabled the test for both 32-bit and 64-bit --
https://github.com/llvm/llvm-project/blob/30c2406e270cc5dab8da813ce5c54e4bb8c40e49/lldb/test/API/functionalities/data-formatter/builtin-formats/TestBuiltinFormats.py#L25

I'll fix the patch and skip the test only for 32-bit ARM. Thank you the explanation!

[DavidSpickett]

which disabled the test for both 32-bit and 64-bit

That one also runs fine on Linux so probably just overly cautious. I see lldb/test/API/commands/expression/rdar44436068/Test128BitsInteger.py as well, that only disables Arm.

Once your changes have passed the bots I'll enable the test in TestBuiltinFormats.py for AArch64 and see what happens.

[werat]

I have relanded the patch with the fixed tests here -- https://github.com/llvm/llvm-project/commit/7d297de95117e783bbfaecbba1f72fc55de05a30

All the tests are passing now.

[DavidSpickett]

Thanks! The Arm/AArch64 Linux bots were green.

lldb/test/API/lang/cpp/const_static_integral_member_int128/TestConstStaticIntegralMemberInt128.py

 """
 Tests const static data members as specified by C++11 [class.static.data]p3
 with (u)int128_t types.
 """
 
 import lldb
 from lldbsuite.test.decorators import *
 from lldbsuite.test.lldbtest import *
 from lldbsuite.test import lldbutil
 
 class TestCase(TestBase):
 
     mydir = TestBase.compute_mydir(__file__)
 
+    # uint128_t not available on arm.
+    @skipIf(archs=["arm", "aarch64"])
     def test_int128(self):
         self.build()
         lldbutil.run_to_source_breakpoint(self, "// break here",
                                           lldb.SBFileSpec("main.cpp"))
 
         # Try to use the (u)int128_t data members which are not supported at
         # the moment. Just verify that LLDB doesn't report an incorrect value
         # for them and just treats them as normal variables (which will lead