1 /*
2  * Copyright 2017, 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 RS2SPIRV_CONTEXT_H
18 #define RS2SPIRV_CONTEXT_H
19 
20 #include "RSAllocationUtils.h"
21 #include "bcinfo/MetadataExtractor.h"
22 
23 #include "llvm/ADT/StringMap.h"
24 #include "llvm/ADT/StringRef.h"
25 
26 #include <limits>
27 #include <stdint.h>
28 #include <vector>
29 
30 // Declare a friend relationship in a class with a test. Used rather that
31 // FRIEND_TEST to avoid globally importing gtest/gtest.h into the main
32 // RSoV header files.
33 #ifdef __HOST__
34 #define RSOV_FRIEND_TEST(test_set_name, individual_test)                       \
35   friend class test_set_name##_##individual_test##_Test
36 #else
37 #define RSOV_FRIEND_TEST(test_set_name, individual_test)
38 #endif // __HOST__
39 
40 namespace bcinfo {
41 class MetadataExtractor;
42 }
43 
44 namespace llvm {
45 class Module;
46 }
47 
48 namespace rs2spirv {
49 
50 // A singleton that keeps state during the compilation from RS LLVM bitcode to
51 // SPIR-V, which provides quick lookup of metadata and shares information
52 // between the passes.
53 class Context {
54   RSOV_FRIEND_TEST(ContextTest, testInitialize);
55 
56 public:
57   static Context &getInstance();
58 
59   Context();
60 
61   // Initialize the internal data struture such as the slot number lookup table,
62   // etc.
63   bool Initialize(std::unique_ptr<bcinfo::MetadataExtractor> ME);
64 
65   // Returns the total number of exported variables
getNumExportVar()66   uint32_t getNumExportVar() const { return mExportVarIndices.size(); }
67 
68   // Adds the mapping from the slot number of an exported variable to the index
69   // of its field in the global buffer
addExportVarIndex(uint32_t slot,uint32_t index)70   void addExportVarIndex(uint32_t slot, uint32_t index) {
71     mExportVarIndices[slot] = index;
72   }
73 
74   // Adds the mapping from the name of an exported variable to the index of its
75   // field in the global buffer
addExportVarIndex(const char * varName,uint32_t index)76   void addExportVarIndex(const char *varName, uint32_t index) {
77     const uint32_t slot = getSlotForExportVar(varName);
78     if (slot == std::numeric_limits<uint32_t>::max()) {
79       assert(0 && "Invalid name for an exported variable");
80       return;
81     }
82     addExportVarIndex(slot, index);
83   }
84 
85   // Given the slot number of an exported variable, returns the index of its
86   // field in the global buffer
getExportVarIndex(uint32_t slot)87   uint32_t getExportVarIndex(uint32_t slot) const {
88     return mExportVarIndices[slot];
89   }
90 
91   // Returns the total number of foreach kernels
getNumForEachKernel()92   uint32_t getNumForEachKernel() const { return mForEachNameToSlot.size(); }
93 
94   // Checks if a name refers to a foreach kernel function
isForEachKernel(llvm::StringRef name)95   bool isForEachKernel(llvm::StringRef name) const {
96     return mForEachNameToSlot.count(name) != 0;
97   }
98 
getMetadata()99   const bcinfo::MetadataExtractor &getMetadata() const { return *mMetadata; }
100 
getGlobalAllocs()101   llvm::SmallVectorImpl<RSAllocationInfo> &getGlobalAllocs() {
102     return mGlobalAllocs;
103   }
104 
105 private:
getSlotForExportVar(const char * varName)106   uint32_t getSlotForExportVar(const char *varName) {
107     const llvm::StringRef strVarName(varName);
108     auto it = mVarNameToSlot.find(strVarName);
109     if (it == mVarNameToSlot.end()) {
110       return std::numeric_limits<uint32_t>::max();
111     }
112     return it->second;
113   }
114 
115   bool mInitialized;
116   // RenderScript metadata embedded in the input LLVM Moduel
117   std::unique_ptr<bcinfo::MetadataExtractor> mMetadata;
118   // A map from exported variable names to their slot numbers
119   llvm::StringMap<uint32_t> mVarNameToSlot;
120   // A map from exported foreach kernel names to their slot numbers
121   llvm::StringMap<uint32_t> mForEachNameToSlot;
122   // These are the indices for each exported variable in the global buffer
123   std::vector<uint32_t> mExportVarIndices;
124   // For Global Allocations; carries global variable -> metadata offset
125   // mapping from an LLVM pass to a SPIRIT pass
126   llvm::SmallVector<RSAllocationInfo, 8> mGlobalAllocs;
127 };
128 
129 } // namespace rs2spirv
130 
131 #endif // RS2SPIRV_CONTEXT_H
132