[clang] [CIR] Upstream initial support for switch statements (PR #137106)

[Henrich Lauko via cfe-commits]

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@@ -802,6 +804,132 @@ Block *cir::BrCondOp::getSuccessorForOperands(ArrayRef<Attribute> operands) {
   return nullptr;
 }
 
+//===----------------------------------------------------------------------===//
+// CaseOp
+//===----------------------------------------------------------------------===//
+
+void cir::CaseOp::getSuccessorRegions(
+    mlir::RegionBranchPoint point, SmallVectorImpl<RegionSuccessor> &regions) {
+  if (!point.isParent()) {
+    regions.push_back(RegionSuccessor());
+    return;
+  }
+  regions.push_back(RegionSuccessor(&getCaseRegion()));
+}
+
+void cir::CaseOp::build(OpBuilder &builder, OperationState &result,
+                        ArrayAttr value, CaseOpKind kind,
+                        OpBuilder::InsertPoint &insertPoint) {
+  OpBuilder::InsertionGuard guardSwitch(builder);
+  result.addAttribute("value", value);
+  result.getOrAddProperties<Properties>().kind =
+      cir::CaseOpKindAttr::get(builder.getContext(), kind);
+  Region *caseRegion = result.addRegion();
+  builder.createBlock(caseRegion);
+
+  insertPoint = builder.saveInsertionPoint();
+}
+
+LogicalResult cir::CaseOp::verify() { return success(); }
+
+//===----------------------------------------------------------------------===//
+// SwitchOp
+//===----------------------------------------------------------------------===//
+
+static ParseResult parseSwitchOp(OpAsmParser &parser, mlir::Region &regions,
+                                 mlir::OpAsmParser::UnresolvedOperand &cond,
+                                 mlir::Type &condType) {
+  cir::IntType intCondType;
+
+  if (parser.parseLParen())
+    return ::mlir::failure();
----------------
xlauko wrote:

No need for `::mlir` use `mlir` also in other places.

https://github.com/llvm/llvm-project/pull/137106