[flang][flang-driver][mlir][OpenMP] atomic control support (#143441)

Atomic Control Options are used to specify architectural characteristics
to help lowering of atomic operations. The options used are:
`-f[no-]atomic-remote-memory`, `-f[no-]atomic-fine-grained-memory`,
 `-f[no-]atomic-ignore-denormal-mode`.
Legacy option `-m[no-]unsafe-fp-atomics` is aliased to
`-f[no-]ignore-denormal-mode`.
More details can be found in
https://github.com/llvm/llvm-project/pull/102569. This PR implements the
frontend support for these options with OpenMP atomic in flang.

Backend changes are available in the draft PR:
https://github.com/llvm/llvm-project/pull/143769 which will be raised
after this merged.

1 files changed, 10 insertions, 0 deletions

diff --git a/flang/lib/Frontend/CompilerInvocation.cpp b/flang/lib/Frontend/CompilerInvocation.cpp
index f55d866..111c5aa4 100644
--- a/flang/lib/Frontend/CompilerInvocation.cpp
+++ b/flang/lib/Frontend/CompilerInvocation.cpp
@@ -512,6 +512,16 @@ static void parseTargetArgs(TargetOptions &opts, llvm::opt::ArgList &args) {
           args.getLastArg(clang::driver::options::OPT_triple))
     opts.triple = a->getValue();
 
+  opts.atomicIgnoreDenormalMode = args.hasFlag(
+      clang::driver::options::OPT_fatomic_ignore_denormal_mode,
+      clang::driver::options::OPT_fno_atomic_ignore_denormal_mode, false);
+  opts.atomicFineGrainedMemory = args.hasFlag(
+      clang::driver::options::OPT_fatomic_fine_grained_memory,
+      clang::driver::options::OPT_fno_atomic_fine_grained_memory, false);
+  opts.atomicRemoteMemory =
+      args.hasFlag(clang::driver::options::OPT_fatomic_remote_memory,
+                   clang::driver::options::OPT_fno_atomic_remote_memory, false);
+
   if (const llvm::opt::Arg *a =
           args.getLastArg(clang::driver::options::OPT_target_cpu))
     opts.cpu = a->getValue();