[llvm] [DAG] Extend the computeOverflowForSignedSub/computeOverflowForUnsignedSub implementations with ConstantRange (PR #67890)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

632022e61c544280685763333685b4743f105f2e looks ok: https://alive2.llvm.org/ce/z/V33G3f

Please can you confirm why -lFortranRuntime is missing?

```console
FAILED: bin/external-hello-world 
: && /usr/local/llvm/16.0.6/bin/clang++ -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 -Wmisleading-indentation -Wctad-maybe-unsupported -fdiagnostics-color -ffunction-sections -fdata-sections -Wno-deprecated-copy -Wno-string-conversion -Wno-ctad-maybe-unsupported -Wno-unused-command-line-argument -Wstring-conversion           -Wcovered-switch-default -Wno-nested-anon-types -O3 -DNDEBUG -Wl,-rpath-link,/home/gitlab-runner-sollve/builds/yP7whQwj9/0/uo-public/llvm-sollve/build/./lib  -Wl,--gc-sections tools/flang/examples/ExternalHelloWorld/CMakeFiles/external-hello-world.dir/external-hello.cpp.o -o bin/external-hello-world  -Wl,-rpath,"\$ORIGIN/../lib:"  -lpthread  -lFortranRuntime && :
/opt/rh/gcc-toolset-12/root/usr/lib/gcc/x86_64-redhat-linux/12/../../../../bin/ld: cannot find -lFortranRuntime: No such file or directory
```

https://github.com/llvm/llvm-project/pull/67890