[flang-commits] [flang] [flang][OpenMP]Add parsing and semantics support for ATOMIC COMPARE (PR #117032)

[Kiran Chandramohan via flang-commits]

================
@@ -121,6 +122,30 @@ program main
    i = j
 !$omp end atomic
 
+!COMPARE
+!$omp atomic compare
+   r = i .eq. j
+!$omp atomic seq_cst compare
+   r = i .eq. j
+!$omp atomic compare seq_cst
+   r = i .eq. j
+!$omp atomic release compare
+   r = i .eq. j
+!$omp atomic compare release
+   r = i .eq. j
+!$omp atomic acq_rel compare
+   r = i .eq. j
+!$omp atomic compare acq_rel
+   r = i .eq. j
+!$omp atomic acquire compare
+   r = i .eq. j
+!$omp atomic compare acquire
+   r = i .eq. j
+!$omp atomic relaxed compare
+   r = i .eq. j
+!$omp atomic compare relaxed
+   r = i .eq. j
----------------
kiranchandramohan wrote:

The 5.1 standard specifies the format as follows. You will have to update the tests.
```
if (x == e) then
  x = d
end if

if (x == e) x = d
```

In 5.2 standard these are described as `conditional-update-atomic`.

https://github.com/llvm/llvm-project/pull/117032