[clang] [HLSL] Implement default constant buffer `$Globals` (PR #125807)

[LLVM Continuous Integration via cfe-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `sanitizer-aarch64-linux-bootstrap-asan` running on `sanitizer-buildbot7` while building `clang` at step 2 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/24/builds/5528

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

```
Step 2 (annotate) failure: 'python ../sanitizer_buildbot/sanitizers/zorg/buildbot/builders/sanitizers/buildbot_selector.py' (failure)
...
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using lld-link: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/lld-link
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using ld64.lld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using wasm-ld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using ld.lld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/ld.lld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using lld-link: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/lld-link
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using ld64.lld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using wasm-ld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/main.py:72: note: The test suite configuration requested an individual test timeout of 0 seconds but a timeout of 900 seconds was requested on the command line. Forcing timeout to be 900 seconds.
-- Testing: 86614 tests, 72 workers --
Testing:  0.. 
FAIL: Clang :: CodeGenHLSL/basic_types.hlsl (9619 of 86614)
******************** TEST 'Clang :: CodeGenHLSL/basic_types.hlsl' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -std=hlsl2021 -finclude-default-header -x hlsl -triple    dxil-pc-shadermodel6.3-library /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl -fnative-half-type    -emit-llvm -disable-llvm-passes -o - | /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/FileCheck /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -std=hlsl2021 -finclude-default-header -x hlsl -triple dxil-pc-shadermodel6.3-library /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl -fnative-half-type -emit-llvm -disable-llvm-passes -o -
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/FileCheck /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl
warning: support for HLSL language version hlsl2021 is incomplete, recommend using hlsl202x instead
1 warning generated.

--

********************
Testing:  0.. 10.. 20
FAIL: Clang :: SemaHLSL/BuiltIns/RWBuffers.hlsl (19163 of 86614)
******************** TEST 'Clang :: SemaHLSL/BuiltIns/RWBuffers.hlsl' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.0-compute -x hlsl -fsyntax-only -verify /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/BuiltIns/RWBuffers.hlsl
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.0-compute -x hlsl -fsyntax-only -verify /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/BuiltIns/RWBuffers.hlsl

--

********************
Testing:  0.. 10.. 20
FAIL: Clang :: SemaHLSL/resource_binding_attr_error_udt.hlsl (19307 of 86614)
******************** TEST 'Clang :: SemaHLSL/resource_binding_attr_error_udt.hlsl' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.3-library -x hlsl -o - -fsyntax-only /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/resource_binding_attr_error_udt.hlsl -verify
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.3-library -x hlsl -o - -fsyntax-only /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/resource_binding_attr_error_udt.hlsl -verify

--
Step 11 (stage2/asan check) failure: stage2/asan check (failure)
...
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using lld-link: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/lld-link
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using ld64.lld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using wasm-ld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using ld.lld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/ld.lld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using lld-link: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/lld-link
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using ld64.lld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/ld64.lld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/llvm/config.py:510: note: using wasm-ld: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/wasm-ld
llvm-lit: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/llvm/utils/lit/lit/main.py:72: note: The test suite configuration requested an individual test timeout of 0 seconds but a timeout of 900 seconds was requested on the command line. Forcing timeout to be 900 seconds.
-- Testing: 86614 tests, 72 workers --
Testing:  0.. 
FAIL: Clang :: CodeGenHLSL/basic_types.hlsl (9619 of 86614)
******************** TEST 'Clang :: CodeGenHLSL/basic_types.hlsl' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -std=hlsl2021 -finclude-default-header -x hlsl -triple    dxil-pc-shadermodel6.3-library /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl -fnative-half-type    -emit-llvm -disable-llvm-passes -o - | /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/FileCheck /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -std=hlsl2021 -finclude-default-header -x hlsl -triple dxil-pc-shadermodel6.3-library /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl -fnative-half-type -emit-llvm -disable-llvm-passes -o -
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/FileCheck /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/CodeGenHLSL/basic_types.hlsl
warning: support for HLSL language version hlsl2021 is incomplete, recommend using hlsl202x instead
1 warning generated.

--

********************
Testing:  0.. 10.. 20
FAIL: Clang :: SemaHLSL/BuiltIns/RWBuffers.hlsl (19163 of 86614)
******************** TEST 'Clang :: SemaHLSL/BuiltIns/RWBuffers.hlsl' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.0-compute -x hlsl -fsyntax-only -verify /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/BuiltIns/RWBuffers.hlsl
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.0-compute -x hlsl -fsyntax-only -verify /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/BuiltIns/RWBuffers.hlsl

--

********************
Testing:  0.. 10.. 20
FAIL: Clang :: SemaHLSL/resource_binding_attr_error_udt.hlsl (19307 of 86614)
******************** TEST 'Clang :: SemaHLSL/resource_binding_attr_error_udt.hlsl' FAILED ********************
Exit Code: 1

Command Output (stderr):
--
RUN: at line 1: /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.3-library -x hlsl -o - -fsyntax-only /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/resource_binding_attr_error_udt.hlsl -verify
+ /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/bin/clang -cc1 -internal-isystem /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm_build_asan/lib/clang/21/include -nostdsysteminc -triple dxil-pc-shadermodel6.3-library -x hlsl -o - -fsyntax-only /home/b/sanitizer-aarch64-linux-bootstrap-asan/build/llvm-project/clang/test/SemaHLSL/resource_binding_attr_error_udt.hlsl -verify

--

```

</details>

https://github.com/llvm/llvm-project/pull/125807