[llvm] [llvm-calc-occupancy] Add an AMDGPU occupancy calculator tool (PR #208727)

[LLVM Continuous Integration via llvm-commits]

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `clang-debian-cpp20` running on `clang-debian-cpp20` while building `llvm` at step 5 "build-unified-tree".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/108/builds/28523

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

```
Step 5 (build-unified-tree) failure: build (failure)
...
144.392 [3/14/6561] Linking CXX shared module lib/CGTestPlugin.so
144.392 [3/13/6562] Linking CXX shared module unittests/Passes/Plugins/DoublerPlugin.so
144.508 [3/12/6563] Linking CXX executable bin/verify-uselistorder
144.510 [3/11/6564] Linking CXX executable bin/sanstats
144.559 [3/10/6565] Linking CXX executable bin/obj2yaml
144.587 [3/9/6566] Linking CXX executable bin/yaml2obj
144.953 [3/8/6567] Linking CXX executable bin/sancov
145.186 [3/7/6568] Linking CXX shared library lib/libclang.so.24.0.0git
145.220 [2/7/6569] Creating library symlink lib/libclang.so.24.0git lib/libclang.so
146.098 [1/7/6570] Building CXX object tools/llvm-calc-occupancy/CMakeFiles/llvm-calc-occupancy.dir/llvm-calc-occupancy.cpp.o
FAILED: tools/llvm-calc-occupancy/CMakeFiles/llvm-calc-occupancy.dir/llvm-calc-occupancy.cpp.o 
ccache /usr/bin/clang++-17 -DLLVM_BUILD_STATIC -D_DEBUG -D_GLIBCXX_ASSERTIONS -D_GLIBCXX_USE_CXX11_ABI=1 -D_GNU_SOURCE -D_LIBCPP_HARDENING_MODE=_LIBCPP_HARDENING_MODE_EXTENSIVE -D__STDC_CONSTANT_MACROS -D__STDC_FORMAT_MACROS -D__STDC_LIMIT_MACROS -I/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/tools/llvm-calc-occupancy -I/vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/tools/llvm-calc-occupancy -I/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/include -I/vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/include -I/vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/lib/Target/AMDGPU -I/vol/worker/clang-debian-cpp20/clang-debian-cpp20/build/lib/Target/AMDGPU -Wno-deprecated-enum-enum-conversion -Wno-deprecated-declarations -Wno-deprecated-anon-enum-enum-conversion -Wno-ambiguous-reversed-operator -fPIC -fno-semantic-interposition -fvisibility-inlines-hidden -Werror=date-time -Werror=unguarded-availability-new -Wall -Wextra -Wno-unused-parameter -Wwrite-strings -Wcast-qual -Wmissing-field-initializers -pedantic -Wno-long-long -Wc++98-compat-extra-semi -Wimplicit-fallthrough -Wcovered-switch-default -Wno-noexcept-type -Wnon-virtual-dtor -Wdelete-non-virtual-dtor -Wsuggest-override -Wstring-conversion -Wno-pass-failed -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -O3 -DNDEBUG -std=c++20 -UNDEBUG -fno-exceptions -funwind-tables -fno-rtti -MD -MT tools/llvm-calc-occupancy/CMakeFiles/llvm-calc-occupancy.dir/llvm-calc-occupancy.cpp.o -MF tools/llvm-calc-occupancy/CMakeFiles/llvm-calc-occupancy.dir/llvm-calc-occupancy.cpp.o.d -o tools/llvm-calc-occupancy/CMakeFiles/llvm-calc-occupancy.dir/llvm-calc-occupancy.cpp.o -c /vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/tools/llvm-calc-occupancy/llvm-calc-occupancy.cpp
/vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/tools/llvm-calc-occupancy/llvm-calc-occupancy.cpp:229:41: error: no member named 'getAddressableNumSGPRs' in namespace 'llvm::AMDGPU::IsaInfo'; did you mean 'getAddressableNumArchVGPRs'?
  229 |   unsigned AddrSGPRs = AMDGPU::IsaInfo::getAddressableNumSGPRs(STI);
      |                        ~~~~~~~~~~~~~~~~~^~~~~~~~~~~~~~~~~~~~~~
      |                                         getAddressableNumArchVGPRs
/vol/worker/clang-debian-cpp20/clang-debian-cpp20/llvm-project/llvm/lib/Target/AMDGPU/Utils/AMDGPUBaseInfo.h:278:10: note: 'getAddressableNumArchVGPRs' declared here
  278 | unsigned getAddressableNumArchVGPRs(const MCSubtargetInfo &STI);
      |          ^
1 error generated.
146.195 [1/6/6571] Linking CXX executable bin/llvm-lto2
147.210 [1/5/6572] Linking CXX executable bin/llvm-opt-fuzzer
147.614 [1/4/6573] Linking CXX executable bin/llvm-split
148.029 [1/3/6574] Linking CXX executable bin/llvm-reduce
148.122 [1/2/6575] Linking CXX executable bin/c-index-test
148.813 [1/1/6576] Linking CXX executable bin/opt
ninja: build stopped: subcommand failed.

```

</details>

https://github.com/llvm/llvm-project/pull/208727