[clang] [llvm] AMDGPU: Use module flags to control xnack and sramecc (PR #204595)

[Shilei Tian via cfe-commits]

================
@@ -5928,10 +5928,18 @@ defm cumode : SimpleMFlag<"cumode",
   " execution mode (AMDGPU only)", m_amdgpu_Features_Group>;
 defm tgsplit : SimpleMFlag<"tgsplit", "Enable", "Disable",
   " threadgroup split execution mode (AMDGPU only)", m_amdgpu_Features_Group>;
-defm xnack : SimpleMFlag<"xnack", "Enable", "Disable",
-  " XNACK (AMDGPU only)", m_amdgpu_Features_Group>;
-defm sramecc : SimpleMFlag<"sramecc", "Enable", "Disable",
-  " SRAMECC (AMDGPU only)", m_amdgpu_Features_Group>;
+def mxnack : Flag<["-"], "mxnack">, Group<m_Group>,
----------------
shiltian wrote:

I wish they would be something like `-mamdgpu-xnack`, to have some sort of namespace, but there is already wavefrontsize64.

https://github.com/llvm/llvm-project/pull/204595