1 /*
2  * Copyright (C) 2016 The Android Open Source Project
3  *
4  * Licensed under the Apache License, Version 2.0 (the "License");
5  * you may not use this file except in compliance with the License.
6  * You may obtain a copy of the License at
7  *
8  *      http://www.apache.org/licenses/LICENSE-2.0
9  *
10  * Unless required by applicable law or agreed to in writing, software
11  * distributed under the License is distributed on an "AS IS" BASIS,
12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
13  * See the License for the specific language governing permissions and
14  * limitations under the License.
15  */
16 
17 #ifndef _STM_TAGGED_PTR_H_
18 #define _STM_TAGGED_PTR_H_
19 
20 #include <stdbool.h>
21 #include <stdint.h>
22 
23 
24 #define TAG	0x80000000UL  //no valid pointers that we care about in STM32F are at 0x80000000 or further
25 
26 typedef uintptr_t TaggedPtr;
27 
taggedPtrToPtr(TaggedPtr tPtr)28 static inline void *taggedPtrToPtr(TaggedPtr tPtr)
29 {
30     return (void*)tPtr;
31 }
32 
taggedPtrToUint(TaggedPtr tPtr)33 static inline uintptr_t taggedPtrToUint(TaggedPtr tPtr)
34 {
35     return tPtr &~ TAG;
36 }
37 
taggedPtrIsPtr(TaggedPtr tPtr)38 static inline bool taggedPtrIsPtr(TaggedPtr tPtr)
39 {
40     return !(tPtr & TAG);
41 }
42 
taggedPtrIsUint(TaggedPtr tPtr)43 static inline bool taggedPtrIsUint(TaggedPtr tPtr)
44 {
45     return !taggedPtrIsPtr(tPtr);
46 }
47 
taggedPtrMakeFromPtr(const void * ptr)48 static inline TaggedPtr taggedPtrMakeFromPtr(const void* ptr)
49 {
50     return (uintptr_t)ptr;
51 }
52 
taggedPtrMakeFromUint(uintptr_t ptr)53 static inline TaggedPtr taggedPtrMakeFromUint(uintptr_t ptr)
54 {
55     return ptr | TAG;
56 }
57 
58 #endif
59 
60