[OpenMP] Fix `omp_get_wtime` function being marked incorrectly as readonly

[jhuber6]

Summary

OpenMP has a list of of optimistic attributes that can be attached to
known runtime functions to aid some analysis. The omp_get_wtime
function incorrectly used the readonly attribute. This is not correct
at the omp_get_wtime function changes values depending on some
external state. This is more correctly modeled with
inaccessiblememonly meaning that the value does not depend on anything
within the module, but can not be removes as it depends on external
state.

Fixes #57578

[tianshilei1992]

LG. That should be the issue introduced by my previous patch.

[fhahn]

Looks like LLVM :: Transforms/OpenMP/add_attributes.ll needs updating.

[jhuber6]

Fixing test

llvm/include/llvm/Frontend/OpenMP/OMPKinds.def

 __OMP_RTL_ATTRS(omp_get_place_proc_ids, GetterArgWriteAttrs, AttributeSet(),
                 ParamAttrs(AttributeSet(), AttributeSet(EnumAttr(NoCapture),
                                                         EnumAttr(WriteOnly))))
 __OMP_RTL_ATTRS(omp_get_place_num, GetterAttrs, AttributeSet(), ParamAttrs())
 __OMP_RTL_ATTRS(omp_get_partition_num_places, GetterAttrs, AttributeSet(),
                 ParamAttrs())
 __OMP_RTL_ATTRS(omp_get_partition_place_nums, GetterAttrs, AttributeSet(),
                 ParamAttrs())
-__OMP_RTL_ATTRS(omp_get_wtime, GetterAttrs, AttributeSet(), ParamAttrs())
+__OMP_RTL_ATTRS(omp_get_wtime, GetterArgWriteAttrs, AttributeSet(), ParamAttrs())
 
 __OMP_RTL_ATTRS(omp_set_num_threads, SetterAttrs, AttributeSet(), ParamAttrs())
 __OMP_RTL_ATTRS(omp_set_dynamic, SetterAttrs, AttributeSet(), ParamAttrs())
 __OMP_RTL_ATTRS(omp_set_nested, SetterAttrs, AttributeSet(), ParamAttrs())
 __OMP_RTL_ATTRS(omp_set_schedule, SetterAttrs, AttributeSet(), ParamAttrs())
 __OMP_RTL_ATTRS(omp_set_max_active_levels, SetterAttrs, AttributeSet(),
                 ParamAttrs())
 

llvm/test/Transforms/OpenMP/add_attributes.ll

 ; OPTIMISTIC: declare dso_local i32 @omp_test_nest_lock(%struct.omp_nest_lock_t*)
 
 ; OPTIMISTIC-NOT: Function Attrs
 ; OPTIMISTIC: declare dso_local void @omp_init_lock_with_hint(%struct.omp_lock_t*, i32)
 
 ; OPTIMISTIC-NOT: Function Attrs
 ; OPTIMISTIC: declare dso_local void @omp_init_nest_lock_with_hint(%struct.omp_nest_lock_t*, i32)
 
-; OPTIMISTIC: ; Function Attrs: inaccessiblememonly nofree nosync nounwind readonly willreturn
+; OPTIMISTIC: ; Function Attrs: inaccessiblemem_or_argmemonly nofree nosync nounwind willreturn
 ; OPTIMISTIC-NEXT: declare dso_local double @omp_get_wtime()
 
 ; OPTIMISTIC-NOT: Function Attrs
 ; OPTIMISTIC: declare dso_local void @use_double(double)
 
 ; OPTIMISTIC-NOT: Function Attrs
 ; OPTIMISTIC: declare dso_local double @omp_get_wtick()