[clang] [CIR] Upstream CIR Dialect TryOp with Catch Attrs (PR #162897)

[Andy Kaylor via cfe-commits]

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@@ -2878,6 +2878,120 @@ LogicalResult cir::TypeInfoAttr::verify(
   return success();
 }
 
+//===----------------------------------------------------------------------===//
+// TryOp
+//===----------------------------------------------------------------------===//
+
+void cir::TryOp::getSuccessorRegions(
+    mlir::RegionBranchPoint point, SmallVectorImpl<RegionSuccessor> &regions) {
+  // If any index all the underlying regions branch back to the parent
+  // operation.
+  if (!point.isParent()) {
+    regions.push_back(RegionSuccessor());
+    return;
+  }
+
+  // If the condition isn't constant, both regions may be executed.
+  regions.push_back(RegionSuccessor(&getTryRegion()));
+
+  // FIXME: optimize, ideas include:
+  // - If we know a target function never throws a specific type, we can
+  //   remove the catch handler.
+  for (mlir::Region &r : this->getCatchRegions())
+    regions.push_back(RegionSuccessor(&r));
+}
+
+static void printCatchRegions(OpAsmPrinter &printer, cir::TryOp op,
+                              mlir::MutableArrayRef<::mlir::Region> regions,
+                              mlir::ArrayAttr catchersAttr) {
+  if (!catchersAttr)
+    return;
+
+  int currCatchIdx = 0;
+  printer << "catch [";
+  llvm::interleaveComma(catchersAttr, printer, [&](const Attribute &a) {
+    if (mlir::isa<cir::CatchUnwindAttr>(a)) {
+      printer.printAttribute(a);
+      printer << " ";
+    } else if (!a) {
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andykaylor wrote:

Shouldn't this be handled by a CatchAllAttr?

https://github.com/llvm/llvm-project/pull/162897