[clang] [CIR] Atomic fetch operation (PR #161631)

[Bruno Cardoso Lopes via cfe-commits]

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@@ -729,6 +729,139 @@ mlir::LogicalResult CIRToLLVMAtomicXchgLowering::matchAndRewrite(
   return mlir::success();
 }
 
+static mlir::LLVM::AtomicBinOp
+getLLVMAtomicBinOp(cir::AtomicFetchKind k, bool isInt, bool isSignedInt) {
+  switch (k) {
+  case cir::AtomicFetchKind::Add:
+    return isInt ? mlir::LLVM::AtomicBinOp::add : mlir::LLVM::AtomicBinOp::fadd;
+  case cir::AtomicFetchKind::Sub:
+    return isInt ? mlir::LLVM::AtomicBinOp::sub : mlir::LLVM::AtomicBinOp::fsub;
+  case cir::AtomicFetchKind::And:
+    return mlir::LLVM::AtomicBinOp::_and;
+  case cir::AtomicFetchKind::Xor:
+    return mlir::LLVM::AtomicBinOp::_xor;
+  case cir::AtomicFetchKind::Or:
+    return mlir::LLVM::AtomicBinOp::_or;
+  case cir::AtomicFetchKind::Nand:
+    return mlir::LLVM::AtomicBinOp::nand;
+  case cir::AtomicFetchKind::Max: {
+    if (!isInt)
+      return mlir::LLVM::AtomicBinOp::fmax;
+    return isSignedInt ? mlir::LLVM::AtomicBinOp::max
+                       : mlir::LLVM::AtomicBinOp::umax;
+  }
+  case cir::AtomicFetchKind::Min: {
+    if (!isInt)
+      return mlir::LLVM::AtomicBinOp::fmin;
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bcardosolopes wrote:

Same for this one!

https://github.com/llvm/llvm-project/pull/161631