[Clang][FMV] Stop emitting implicit default version using target_clones. (#141808)

With the current behavior the following example yields a linker error:
"multiple definition of `foo.default'"

// Translation Unit 1
__attribute__((target_clones("dotprod, sve"))) int foo(void) { return 1; }

// Translation Unit 2
int foo(void) { return 0; }
__attribute__((target_version("dotprod"))) int foo(void);
__attribute__((target_version("sve"))) int foo(void);
int bar(void) { return foo(); }

That is because foo.default is generated twice. As a user I don't find
this particularly intuitive. If I wanted the default to be generated in
TU1 I'd rather write target_clones("dotprod, sve", "default")
explicitly.

When changing the code I noticed that the RISC-V target defers the
resolver emission when encountering a target_version definition. This
seems accidental since it only makes sense for AArch64, where we only
emit a resolver once we've processed the entire TU, and only if the
default version is present. I've changed this so that RISC-V immediately
emmits the resolver. I adjusted the codegen tests since the functions
now appear in a different order.

Implements https://github.com/ARM-software/acle/pull/377
13 files changed
tree: c267a3575e52a159f224fe4ed465e1866a86ea38
  1. .ci/
  2. .github/
  3. bolt/
  4. clang/
  5. clang-tools-extra/
  6. cmake/
  7. compiler-rt/
  8. cross-project-tests/
  9. flang/
  10. flang-rt/
  11. libc/
  12. libclc/
  13. libcxx/
  14. libcxxabi/
  15. libunwind/
  16. lld/
  17. lldb/
  18. llvm/
  19. llvm-libgcc/
  20. mlir/
  21. offload/
  22. openmp/
  23. polly/
  24. pstl/
  25. runtimes/
  26. third-party/
  27. utils/
  28. .clang-format
  29. .clang-format-ignore
  30. .clang-tidy
  31. .git-blame-ignore-revs
  32. .gitattributes
  33. .gitignore
  34. .mailmap
  35. CODE_OF_CONDUCT.md
  36. CONTRIBUTING.md
  37. LICENSE.TXT
  38. pyproject.toml
  39. README.md
  40. SECURITY.md
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