[CIR] Const member expr for struct type (llvm#164172)

Upstream support the const member expr for struct type

Author: AmrDeveloper

clang/lib/CIR/CodeGen/CIRGenExprAggregate.cpp

@@ -280,6 +280,7 @@ class AggExprEmitter : public StmtVisitor<AggExprEmitter> {
   void VisitUnaryDeref(UnaryOperator *e) { emitAggLoadOfLValue(e); }
   void VisitStringLiteral(StringLiteral *e) { emitAggLoadOfLValue(e); }
   void VisitCompoundLiteralExpr(CompoundLiteralExpr *e);
+
   void VisitPredefinedExpr(const PredefinedExpr *e) {
     cgf.cgm.errorNYI(e->getSourceRange(),
                      "AggExprEmitter: VisitPredefinedExpr");
@@ -670,7 +671,7 @@ void AggExprEmitter::emitNullInitializationToLValue(mlir::Location loc,
       return;
     }
 
-    cgf.cgm.errorNYI("emitStoreThroughBitfieldLValue");
+    cgf.emitStoreThroughBitfieldLValue(RValue::get(null), lv);
     return;
   }
 

clang/lib/CIR/CodeGen/CIRGenExprScalar.cpp

@@ -2041,8 +2041,9 @@ mlir::Value ScalarExprEmitter::VisitMemberExpr(MemberExpr *e) {
   assert(!cir::MissingFeatures::tryEmitAsConstant());
   Expr::EvalResult result;
   if (e->EvaluateAsInt(result, cgf.getContext(), Expr::SE_AllowSideEffects)) {
-    cgf.cgm.errorNYI(e->getSourceRange(), "Constant interger member expr");
-    // Fall through to emit this as a non-constant access.
+    llvm::APSInt value = result.Val.getInt();
+    cgf.emitIgnoredExpr(e->getBase());
+    return builder.getConstInt(cgf.getLoc(e->getExprLoc()), value);
   }
   return emitLoadOfLValue(e);
 }

clang/test/CIR/CodeGen/struct.cpp

@@ -280,3 +280,67 @@ void bin_comma() {
 // OGCG: define{{.*}} void @_Z9bin_commav()
 // OGCG:   %[[A_ADDR:.*]] = alloca %struct.CompleteS, align 4
 // OGCG:   call void @llvm.memset.p0.i64(ptr align 4 %[[A_ADDR]], i8 0, i64 8, i1 false)
+
+void compound_literal_expr() { CompleteS a = (CompleteS){}; }
+
+// CIR: %[[A_ADDR:.*]] = cir.alloca !rec_CompleteS, !cir.ptr<!rec_CompleteS>, ["a", init]
+// CIR: %[[A_ELEM_0_PTR:.*]] = cir.get_member %[[A_ADDR]][0] {name = "a"} : !cir.ptr<!rec_CompleteS> -> !cir.ptr<!s32i>
+// CIR: %[[CONST_0:.*]] = cir.const #cir.int<0> : !s32i
+// CIR: cir.store{{.*}} %[[CONST_0]], %[[A_ELEM_0_PTR]] : !s32i, !cir.ptr<!s32i>
+// CIR: %[[A_ELEM_1_PTR:.*]] = cir.get_member %[[A_ADDR]][1] {name = "b"} : !cir.ptr<!rec_CompleteS> -> !cir.ptr<!s8i>
+// CIR: %[[CONST_0:.*]] = cir.const #cir.int<0> : !s8i
+// CIR: cir.store{{.*}} %[[CONST_0]], %[[A_ELEM_1_PTR]] : !s8i, !cir.ptr<!s8i>
+
+// TODO(cir): zero-initialize the padding
+
+// LLVM: %[[A_ADDR:.*]] = alloca %struct.CompleteS, i64 1, align 4
+// LLVM: %[[A_ELEM_0_PTR:.*]] = getelementptr %struct.CompleteS, ptr %[[A_ADDR]], i32 0, i32 0
+// LLVM: store i32 0, ptr %[[A_ELEM_0_PTR]], align 4
+// LLVM: %[[A_ELEM_1_PTR:.*]] = getelementptr %struct.CompleteS, ptr %[[A_ADDR]], i32 0, i32 1
+// LLVM: store i8 0, ptr %[[A_ELEM_1_PTR]], align 4
+
+// OGCG: %[[A_ADDR:.*]] = alloca %struct.CompleteS, align 4
+// OGCG: call void @llvm.memset.p0.i64(ptr align 4 %[[A_ADDR]], i8 0, i64 8, i1 false)
+
+struct StructWithConstMember {
+  int a : 1;
+};
+
+void struct_with_const_member_expr() {
+  int a = (StructWithConstMember){}.a;
+}
+
+// CIR: %[[A_ADDR:.*]] = cir.alloca !s32i, !cir.ptr<!s32i>, ["a", init]
+// CIR: %[[RESULT:.*]] = cir.scope {
+// CIR:   %[[REF_ADDR:.*]] = cir.alloca !rec_StructWithConstMember, !cir.ptr<!rec_StructWithConstMember>, ["ref.tmp0"]
+// CIR:   %[[ELEM_0_PTR:.*]] = cir.get_member %[[REF_ADDR]][0] {name = "a"} : !cir.ptr<!rec_StructWithConstMember> -> !cir.ptr<!u8i>
+// CIR:   %[[CONST_0:.*]] = cir.const #cir.int<0> : !s32i
+// CIR:   %[[SET_BF:.*]] = cir.set_bitfield{{.*}} (#bfi_a, %[[ELEM_0_PTR]] : !cir.ptr<!u8i>, %[[CONST_0]] : !s32i) -> !s32i
+// CIR:   %[[CONST_0:.*]] = cir.const #cir.int<0> : !s32i
+// CIR:   cir.yield %[[CONST_0]] : !s32i
+// CIR: } : !s32i
+// CIR: cir.store{{.*}} %[[RESULT]], %[[A_ADDR]] : !s32i, !cir.ptr<!s32i>
+
+// TODO(cir): zero-initialize the padding
+
+// LLVM:  %[[REF_ADDR:.*]] = alloca %struct.StructWithConstMember, i64 1, align 4
+// LLVM:  %[[A_ADDR:.*]] = alloca i32, i64 1, align 4
+// LLVM:  br label %[[BF_LABEL:.*]]
+// LLVM: [[BF_LABEL]]:
+// LLVM:  %[[ELEM_0_PTR:.*]] = getelementptr %struct.StructWithConstMember, ptr %[[REF_ADDR]], i32 0, i32 0
+// LLVM:  %[[TMP_REF:.*]] = load i8, ptr %[[ELEM_0_PTR]], align 4
+// LLVM:  %[[BF_CLEAR:.*]] = and i8 %[[TMP_REF]], -2
+// LLVM:  %[[BF_SET:.*]] = or i8 %[[BF_CLEAR]], 0
+// LLVM:  store i8 %[[BF_SET]], ptr %[[ELEM_0_PTR]], align 4
+// LLVM:  br label %[[RESULT_LABEL:.*]]
+// LLVM: [[RESULT_LABEL]]:
+// LLVM:  %[[RESULT:.*]] = phi i32 [ 0, %[[BF_LABEL]] ]
+// LLVM:  store i32 %[[RESULT]], ptr %[[A_ADDR]], align 4
+
+// OGCG: %[[A_ADDR:.*]] = alloca i32, align 4
+// OGCG: %[[REF_ADDR:.*]] = alloca %struct.StructWithConstMember, align 4
+// OGCG: %[[TMP_REF:.*]] = load i8, ptr %[[REF_ADDR]], align 4
+// OGCG: %[[BF_CLEAR:.*]] = and i8 %[[TMP_REF]], -2
+// OGCG: %[[BF_SET:.*]] = or i8 %[[BF_CLEAR]], 0
+// OGCG: store i8 %[[BF_SET]], ptr %[[REF_ADDR]], align 4
+// OGCG: store i32 0, ptr %[[A_ADDR]], align 4