[llvm] AArch64: Add tests for arm64ec for special case math functions (PR #147234)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `llvm-clang-x86_64-expensive-checks-debian` running on `gribozavr4` while building `llvm` at step 6 "test-build-unified-tree-check-all".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/16/builds/22254

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 6 (test-build-unified-tree-check-all) failure: test (failure)
******************** TEST 'LLVM :: TableGen/RuntimeLibcallEmitter-conflict-warning.td' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
/b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llvm-tblgen -gen-runtime-libcalls -I /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/../../include /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/RuntimeLibcallEmitter-conflict-warning.td 2> /b/1/llvm-clang-x86_64-expensive-checks-debian/build/test/TableGen/Output/RuntimeLibcallEmitter-conflict-warning.td.tmp.err | /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/FileCheck /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/RuntimeLibcallEmitter-conflict-warning.td # RUN: at line 1
+ /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/FileCheck /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/RuntimeLibcallEmitter-conflict-warning.td
+ /b/1/llvm-clang-x86_64-expensive-checks-debian/build/bin/llvm-tblgen -gen-runtime-libcalls -I /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/../../include /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/RuntimeLibcallEmitter-conflict-warning.td
/b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/RuntimeLibcallEmitter-conflict-warning.td:29:16: error: CHECK-NEXT: is not on the line after the previous match
// CHECK-NEXT: {RTLIB::SOME_FUNC, RTLIB::func_b}, // func_b
               ^
<stdin>:98:2: note: 'next' match was here
 {RTLIB::SOME_FUNC, RTLIB::func_b}, // func_b
 ^
<stdin>:72:49: note: previous match ended here
 static const LibcallImplPair LibraryCalls[] = {
                                                ^
<stdin>:73:1: note: non-matching line after previous match is here
 {RTLIB::SOME_FUNC, RTLIB::func_a}, // func_a
^

Input file: <stdin>
Check file: /b/1/llvm-clang-x86_64-expensive-checks-debian/llvm-project/llvm/test/TableGen/RuntimeLibcallEmitter-conflict-warning.td

-dump-input=help explains the following input dump.

Input was:
<<<<<<
         .
         .
         .
        93:  
        94:  if (isTargetArchC()) { 
        95:  static const LibcallImplPair LibraryCalls[] = { 
        96:  {RTLIB::ANOTHER_DUP, RTLIB::dup0}, // dup0 
        97:  {RTLIB::OTHER_FUNC, RTLIB::other_func}, // other_func 
        98:  {RTLIB::SOME_FUNC, RTLIB::func_b}, // func_b 
next:29      !~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~  error: match on wrong line
        99:  }; 
       100:  
       101:  for (const auto [Func, Impl] : LibraryCalls) { 
       102:  setLibcallImpl(Func, Impl); 
       103:  } 
         .
         .
         .
>>>>>>

--

...

```

</details>

https://github.com/llvm/llvm-project/pull/147234