[llvm] [coverage] Add option for keeping mappings order (PR #91600)

[via llvm-commits]

Lambdaris wrote:

Test failed at 
```
FAIL: Clang :: Sema/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c (15637 of 20514)
******************** TEST 'Clang :: Sema/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/bin/clang -cc1 -internal-isystem /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/lib/clang/19/include -nostdsysteminc -triple aarch64-none-linux-gnu -target-feature +sme -fsyntax-only -verify -emit-llvm /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/clang/test/Sema/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c
+ /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/bin/clang -cc1 -internal-isystem /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/lib/clang/19/include -nostdsysteminc -triple aarch64-none-linux-gnu -target-feature +sme -fsyntax-only -verify -emit-llvm /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/clang/test/Sema/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c
error: 'expected-error' diagnostics seen but not expected: 
  (frontend): '-fsyntax-only' action ignored; '-emit-llvm' action specified previously

--
********************
```

And 
```
FAIL: Clang :: CodeGen/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c (5494 of 20514)
******************** TEST 'Clang :: CodeGen/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c' FAILED ********************
Exit Code: 2

Command Output (stderr):
--
RUN: at line 2: /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/bin/clang -cc1 -internal-isystem /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/lib/clang/19/include -nostdsysteminc                               -fclang-abi-compat=latest -triple aarch64-none-linux-gnu -target-feature +sme2 -target-feature +sme-f16f16 -target-feature +b16b16 -O2 -S -Werror -Wall -emit-llvm -o - /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/clang/test/CodeGen/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c | /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/bin/FileCheck /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/clang/test/CodeGen/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c
+ /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/bin/clang -cc1 -internal-isystem /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/lib/clang/19/include -nostdsysteminc -fclang-abi-compat=latest -triple aarch64-none-linux-gnu -target-feature +sme2 -target-feature +sme-f16f16 -target-feature +b16b16 -O2 -S -Werror -Wall -emit-llvm -o - /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/clang/test/CodeGen/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c
+ /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/bin/FileCheck /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/clang/test/CodeGen/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c
error: '-S' action ignored; '-emit-llvm' action specified previously
FileCheck error: '<stdin>' is empty.
FileCheck command line:  /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/build/bin/FileCheck /var/lib/buildkite-agent/builds/linux-56-59b8f5d88-qrksl-1/llvm-project/github-pull-requests/clang/test/CodeGen/aarch64-sme2-intrinsics/acle_sme2_add_sub_za16.c

--

********************
```
Have no idea what causes these. Could someone help?

https://github.com/llvm/llvm-project/pull/91600