[clang] [llvm] [Mips] Add r5900 (PlayStation 2 Emotion Engine) CPU support (PR #176666)

[Rick Gaiser via cfe-commits]

================
@@ -278,6 +280,65 @@ static bool hasUnoccupiedSlot(const MachineInstr *MI) {
   return MI->hasDelaySlot() && !MI->isBundledWithSucc();
 }
 
+/// Check if a branch is a short backward loop that triggers the R5900 erratum.
+/// The erratum occurs when:
+/// - A loop has 6 or fewer instructions (including branch + delay slot)
----------------
rickgaiser wrote:

I've updated the comment to reference the original source, and include the exact working from that source. If ok this can be resolved.

https://github.com/llvm/llvm-project/pull/176666