[DebugInfo][test] XFAIL DebugInfo/Generic/missing-abstract-variable.ll on SPARC

[ro]

Summary

DebugInfo/Generic/missing-abstract-variable.ll FAILs on SPARC. When x is inlined into a, the variable s is elided completely, so the corresponding CHECKs fail. Exactly the same happens on RISCV and the test has already been XFAILed there.

This patch does the same on SPARC.

Tested on sparcv9-sun-solaris2.11.

[jmorse]

LGTM, given the long list of other XFails.

I get the feeling that this test isn't best placed as a Generic test, that's something we'll have to fix in the future.

llvm/test/DebugInfo/Generic/missing-abstract-variable.ll

 ; RUN: %llc_dwarf -O0 -filetype=obj < %s | llvm-dwarfdump -debug-info - | FileCheck %s
 
 ; The formal parameter 'b' for Function 'x' when inlined within 'a' is lost on
 ; powerpc64 (and on x86_64 at at least -O2). Presumably this is a SelectionDAG
 ; issue.
 ; FIXME: arm64 is an alias for aarch64 on macs, apparently?
-; XFAIL: powerpc64, aarch64, arm64, hexagon, riscv
+; XFAIL: powerpc64, aarch64, arm64, hexagon, riscv, sparc
 
 ; Build from the following source with clang -O2.
 
 ; The important details are that 'x's abstract definition is first built during
 ; the definition of 'b', where the parameter to 'x' is constant and so 'x's 's'
 ; variable is optimized away. No abstract definition DIE for 's' is constructed.
 ; Then, during 'a' emission, the abstract DbgVariable for 's' is created, but
 ; the abstract DIE isn't (since the abstract definition for 'b' is already