[CIR] Add dedicated CIR op for setjmp

clang/include/clang/CIR/Dialect/IR/CIROps.td

@@ -4698,6 +4698,26 @@ def CIR_EhTypeIdOp : CIR_Op<"eh.typeid",
   }];
 }
 
+def CIR_EhSetjmp : CIR_Op<"eh.setjmp"> {
+  let summary = "CIR setjmp operation";
+  let description = [{
+    "Saves various information about the calling
+       environment (typically, the stack pointer, the instruction
+       pointer, possibly the values of other registers and the signal
+       mask) in the buffer env for later use by longjmp().  In this case,
+       setjmp() returns 0. When retuned from a longjmp(), setjmp returns the 
+       value passed into longjmp()."
+  }];
+
+  let arguments = (ins CIR_PointerType:$buf, UnitAttr:$builtin);
+  let results = (outs CIR_SInt32:$res);
+  let assemblyFormat = [{
+      $buf `:` type($buf)
+      (`,` `builtin` $builtin^)?
+      `->` type(results) attr-dict
+    }];
+}
+
 //===----------------------------------------------------------------------===//
 // CopyOp
 //===----------------------------------------------------------------------===//

clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.cpp

@@ -4288,6 +4288,27 @@ mlir::LogicalResult CIRToLLVMEhTypeIdOpLowering::matchAndRewrite(
   return mlir::success();
 }
 
+mlir::LogicalResult CIRToLLVMEhSjljSetjmpOpLowering::matchAndRewrite(
+    cir::EhSetjmp op, OpAdaptor adaptor,
+    mlir::ConversionPatternRewriter &rewriter) const {
+  mlir::Type returnType = typeConverter->convertType(op.getType());
+  if (op.getBuiltinAttr()) {
+    mlir::LLVM::CallIntrinsicOp newOp =
+        createCallLLVMIntrinsicOp(rewriter, op.getLoc(), "llvm.eh.sjlj.setjmp",
+                                  returnType, adaptor.getBuf());
+    rewriter.replaceOp(op, newOp);
+  } else {
+    StringRef fnName = "_setjmp";
+    auto llvmPtrTy = mlir::LLVM::LLVMPointerType::get(rewriter.getContext());
+    auto fnType = mlir::LLVM::LLVMFunctionType::get(returnType, llvmPtrTy,
+                                                    /*isVarArg=*/false);
+    getOrCreateLLVMFuncOp(rewriter, op, fnName, fnType);
+    rewriter.replaceOpWithNewOp<mlir::LLVM::CallOp>(op, returnType, fnName,
+                                                    adaptor.getBuf());
+  }
+  return mlir::success();
+}
+
 mlir::LogicalResult CIRToLLVMCatchParamOpLowering::matchAndRewrite(
     cir::CatchParamOp op, OpAdaptor adaptor,
     mlir::ConversionPatternRewriter &rewriter) const {
@@ -4531,6 +4552,7 @@ void populateCIRToLLVMConversionPatterns(
       CIRToLLVMDerivedClassAddrOpLowering,
       CIRToLLVMEhInflightOpLowering,
       CIRToLLVMEhTypeIdOpLowering,
+      CIRToLLVMEhSjljSetjmpOpLowering,
       CIRToLLVMExpectOpLowering,
       CIRToLLVMExtractMemberOpLowering,
       CIRToLLVMFrameAddrOpLowering,

clang/lib/CIR/Lowering/DirectToLLVM/LowerToLLVM.h

@@ -1220,6 +1220,16 @@ class CIRToLLVMEhTypeIdOpLowering
                   mlir::ConversionPatternRewriter &) const override;
 };
 
+class CIRToLLVMEhSjljSetjmpOpLowering
+    : public mlir::OpConversionPattern<cir::EhSetjmp> {
+public:
+  using mlir::OpConversionPattern<cir::EhSetjmp>::OpConversionPattern;
+
+  mlir::LogicalResult
+  matchAndRewrite(cir::EhSetjmp op, OpAdaptor,
+                  mlir::ConversionPatternRewriter &) const override;
+};
+
 class CIRToLLVMCatchParamOpLowering
     : public mlir::OpConversionPattern<cir::CatchParamOp> {
 public:

clang/test/CIR/Lowering/setjmp-longjmp.cir

@@ -0,0 +1,28 @@
+// RUN: cir-opt %s -cir-to-llvm -o %t.ll
+// RUN: FileCheck %s --input-file=%t.ll -check-prefix=MLIR
+!s32i = !cir.int<s, 32>
+!p32  = !cir.ptr<!s32i>
+
+module {
+  // MLIR: module {
+  cir.func @test_setjmp(%arg0 : !p32) -> !s32i {
+
+    // MLIR:  llvm.func @test_setjmp([[ARG0:%.*]]: !llvm.ptr) -> i32
+    // MLIR-NEXT:    [[RET:%.*]] = llvm.call_intrinsic "llvm.eh.sjlj.setjmp"([[ARG0]]) : (!llvm.ptr) -> i32
+    // MLIR-NEXT:    llvm.return [[RET:%.*]] : i32
+    // MLIR-NEXT:  }
+    %0 = cir.eh.setjmp %arg0 : !p32, builtin -> !s32i
+    cir.return %0 : !s32i
+  }
+  cir.func @test_setjmp_2(%arg0 : !p32) -> !s32i {
+
+    // MLIR:  llvm.func @test_setjmp_2([[ARG0:%.*]]: !llvm.ptr) -> i32
+    // MLIR-NEXT:    [[RET:%.*]] = llvm.call @_setjmp([[ARG0]]) : (!llvm.ptr) -> i32
+    // MLIR-NEXT:    llvm.return [[RET:%.*]] : i32
+    // MLIR-NEXT:  }
+    %0 = cir.eh.setjmp %arg0 : !p32 -> !s32i
+    cir.return %0 : !s32i
+  }
+  // MLIR: }
+}
+