[CIR] Backport CXXScalarValueInitExpr support for ComplexType (#1824)

Backport CXXScalarValueInitExpr support for ComplexType from the
upstream

Author: AmrDeveloper

clang/lib/CIR/CodeGen/CIRGenExprComplex.cpp

@@ -174,9 +174,13 @@ class ComplexExprEmitter : public StmtVisitor<ComplexExprEmitter, mlir::Value> {
     Scope.ForceCleanup({&V});
     return V;
   }
+
   mlir::Value VisitCXXScalarValueInitExpr(CXXScalarValueInitExpr *E) {
-    llvm_unreachable("NYI");
+    mlir::Location loc = CGF.getLoc(E->getExprLoc());
+    mlir::Type complexTy = CGF.convertType(E->getType());
+    return Builder.getNullValue(complexTy, loc);
   }
+
   mlir::Value VisitImplicitValueInitExpr(ImplicitValueInitExpr *E) {
     llvm_unreachable("NYI");
   }

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

@@ -731,8 +731,9 @@ mlir::Value CirAttrToValue::visitCirAttr(cir::GlobalViewAttr globalAttr) {
     }
     auto resTy = addrOp.getType();
     auto eltTy = converter->convertType(sourceType);
-    addrOp = rewriter.create<mlir::LLVM::GEPOp>(loc, resTy, eltTy, addrOp,
-                                                indices, mlir::LLVM::GEPNoWrapFlags::inbounds);
+    addrOp = rewriter.create<mlir::LLVM::GEPOp>(
+        loc, resTy, eltTy, addrOp, indices,
+        mlir::LLVM::GEPNoWrapFlags::inbounds);
   }
 
   if (auto intTy = mlir::dyn_cast<cir::IntType>(globalAttr.getType())) {
@@ -1205,8 +1206,9 @@ mlir::LogicalResult CIRToLLVMVTTAddrPointOpLowering::matchAndRewrite(
     offsets.push_back(0);
     offsets.push_back(adaptor.getOffset());
   }
-  rewriter.replaceOpWithNewOp<mlir::LLVM::GEPOp>(op, resultType, eltType,
-                                                 llvmAddr, offsets, mlir::LLVM::GEPNoWrapFlags::inbounds);
+  rewriter.replaceOpWithNewOp<mlir::LLVM::GEPOp>(
+      op, resultType, eltType, llvmAddr, offsets,
+      mlir::LLVM::GEPNoWrapFlags::inbounds);
   return mlir::success();
 }
 
@@ -1903,9 +1905,18 @@ mlir::LogicalResult CIRToLLVMConstantOpLowering::matchAndRewrite(
         typeConverter->convertType(op.getType()),
         mlir::cast<cir::FPAttr>(op.getValue()).getValue());
   } else if (auto complexTy = mlir::dyn_cast<cir::ComplexType>(op.getType())) {
+    mlir::Type complexElemTy = complexTy.getElementType();
+    mlir::Type complexElemLLVMTy = typeConverter->convertType(complexElemTy);
+
+    if (auto zeroInitAttr = mlir::dyn_cast<cir::ZeroAttr>(op.getValue())) {
+      mlir::TypedAttr zeroAttr = rewriter.getZeroAttr(complexElemLLVMTy);
+      mlir::ArrayAttr array = rewriter.getArrayAttr({zeroAttr, zeroAttr});
+      rewriter.replaceOpWithNewOp<mlir::LLVM::ConstantOp>(
+          op, getTypeConverter()->convertType(op.getType()), array);
+      return mlir::success();
+    }
+
     auto complexAttr = mlir::cast<cir::ComplexAttr>(op.getValue());
-    auto complexElemTy = complexTy.getElementType();
-    auto complexElemLLVMTy = typeConverter->convertType(complexElemTy);
 
     mlir::Attribute components[2];
     if (mlir::isa<cir::IntType>(complexElemTy)) {
@@ -3881,8 +3892,9 @@ mlir::LogicalResult CIRToLLVMVTableAddrPointOpLowering::matchAndRewrite(
       op.getAddressPointAttr().getOffset()};
 
   assert(eltType && "Shouldn't ever be missing an eltType here");
-  rewriter.replaceOpWithNewOp<mlir::LLVM::GEPOp>(op, targetType, eltType,
-                                                 symAddr, offsets, mlir::LLVM::GEPNoWrapFlags::inbounds);
+  rewriter.replaceOpWithNewOp<mlir::LLVM::GEPOp>(
+      op, targetType, eltType, symAddr, offsets,
+      mlir::LLVM::GEPNoWrapFlags::inbounds);
 
   return mlir::success();
 }
@@ -3908,7 +3920,8 @@ mlir::LogicalResult CIRToLLVMVTableGetVirtualFnAddrOpLowering::matchAndRewrite(
   llvm::SmallVector<mlir::LLVM::GEPArg> offsets =
       llvm::SmallVector<mlir::LLVM::GEPArg>{op.getIndex()};
   rewriter.replaceOpWithNewOp<mlir::LLVM::GEPOp>(
-      op, targetType, eltType, adaptor.getVptr(), offsets, mlir::LLVM::GEPNoWrapFlags::inbounds);
+      op, targetType, eltType, adaptor.getVptr(), offsets,
+      mlir::LLVM::GEPNoWrapFlags::inbounds);
   return mlir::success();
 }
 
@@ -4000,7 +4013,9 @@ mlir::LogicalResult CIRToLLVMInlineAsmOpLowering::matchAndRewrite(
       op, llResTy, llvmOperands, op.getAsmStringAttr(), op.getConstraintsAttr(),
       op.getSideEffectsAttr(),
       /*is_align_stack*/ mlir::UnitAttr(),
-      /*tail_call_kind*/ mlir::LLVM::TailCallKindAttr::get(getContext(), mlir::LLVM::tailcallkind::TailCallKind::None),
+      /*tail_call_kind*/
+      mlir::LLVM::TailCallKindAttr::get(
+          getContext(), mlir::LLVM::tailcallkind::TailCallKind::None),
       mlir::LLVM::AsmDialectAttr::get(getContext(), llDialect),
       rewriter.getArrayAttr(opAttrs));
 

clang/test/CIR/CodeGen/complex.cpp

@@ -15,6 +15,18 @@ void complex_functional_cast() {
 // LLVM: %[[INIT:.*]] = alloca { i32, i32 }, i64 1, align 4
 // LLVM: store { i32, i32 } zeroinitializer, ptr %[[INIT]], align 4
 
+void complex_cxx_scalar_value_init_expr() {
+  using IntComplex = int _Complex;
+  int _Complex a = IntComplex();
+}
+
+// CIR: %[[INIT:.*]] = cir.alloca !cir.complex<!s32i>, !cir.ptr<!cir.complex<!s32i>>, ["a", init]
+// CIR: %[[COMPLEX:.*]] = cir.const #cir.zero : !cir.complex<!s32i>
+// CIR: cir.store align(4) %[[COMPLEX]], %[[INIT]] : !cir.complex<!s32i>, !cir.ptr<!cir.complex<!s32i>>
+
+// LLVM: %[[INIT:.*]] = alloca { i32, i32 }, i64 1, align 4
+// LLVM: store { i32, i32 } zeroinitializer, ptr %[[INIT]], align 4
+
 void complex_abstract_condition(bool cond, int _Complex a, int _Complex b) {
   int _Complex c = cond ? a : b;
 }