| /* |
| * Copyright 2015, The Android Open Source Project |
| * |
| * Licensed under the Apache License, Version 2.0 (the "License"); |
| * you may not use this file except in compliance with the License. |
| * You may obtain a copy of the License at |
| * |
| * http://www.apache.org/licenses/LICENSE-2.0 |
| * |
| * Unless required by applicable law or agreed to in writing, software |
| * distributed under the License is distributed on an "AS IS" BASIS, |
| * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied. |
| * See the License for the specific language governing permissions and |
| * limitations under the License. |
| */ |
| |
| #include "Assert.h" |
| #include "Log.h" |
| #include "RSUtils.h" |
| |
| #include "rsDefines.h" |
| |
| #include <llvm/IR/Constant.h> |
| #include <llvm/IR/Constants.h> |
| #include <llvm/IR/Type.h> |
| #include <llvm/IR/Module.h> |
| #include <llvm/IR/Function.h> |
| #include <llvm/Pass.h> |
| |
| #include <sstream> |
| #include <vector> |
| |
| namespace { |
| |
| const bool kDebugGlobalInfo = false; |
| |
| /* RSGlobalInfoPass: Embeds additional information about RenderScript global |
| * variables into the Module. The 5 variables added are specified as follows: |
| * 1) .rs.global_entries |
| * i32 - int |
| * Optional number of global variables. |
| * 2) .rs.global_names |
| * [N * i8*] - const char *[N] |
| * Optional global variable name info. Each entry corresponds to the name |
| * of 1 of the N global variables. |
| * 3) .rs.global_addresses |
| * [N * i8*] - void*[N] or void** |
| * Optional global variable address info. Each entry corresponds to the |
| * address of 1 of the N global variables. |
| * 4) .rs.global_sizes |
| * [N * i32] or [N * i64] - size_t[N] |
| * Optional global variable size info. Each entry corresponds to the size |
| * of 1 of the N global variables. |
| * 5) .rs.global_properties |
| * [N * i32] |
| * Optional global properties. Each entry corresponds to the properties |
| * for 1 of the N global variables. The 32-bit integer for properties |
| * can be broken down as follows: |
| * bit(s) Encoded value |
| * ------ ------------- |
| * 18 Pointer (1 is pointer, 0 is non-pointer) |
| * 17 Static (1 is static, 0 is extern) |
| * 16 Constant (1 is const, 0 is non-const) |
| * 15 - 0 RsDataType (see frameworks/rs/rsDefines.h for more info) |
| */ |
| class RSGlobalInfoPass: public llvm::ModulePass { |
| private: |
| // If true, we don't include information about immutable global variables |
| // in our various exported data structures. |
| bool mSkipConstants; |
| |
| // Encodes properties of the GlobalVariable into a uint32_t. |
| // These values are used to populate the .rs.global_properties array. |
| static uint32_t getEncodedProperties(const llvm::GlobalVariable &GV) { |
| auto GlobalType = GV.getType()->getPointerElementType(); |
| |
| // We start by getting the RsDataType and placing it into our result. |
| uint32_t result = getRsDataTypeForType(GlobalType); |
| bccAssert(!(result & ~RS_GLOBAL_TYPE)); // Can only alter lower 16-bits. |
| |
| if (GlobalType->isPointerTy()) { |
| // Global variables that are pointers can all be used with "bind". |
| result |= RS_GLOBAL_POINTER; |
| } |
| |
| if (GV.isConstant()) { |
| result |= RS_GLOBAL_CONSTANT; |
| } |
| |
| if (GV.getLinkage() == llvm::GlobalValue::InternalLinkage) { |
| // We only have internal linkage in RS to signify static. |
| result |= RS_GLOBAL_STATIC; |
| } |
| |
| return result; |
| } |
| |
| public: |
| static char ID; |
| |
| explicit RSGlobalInfoPass(bool pSkipConstants = false) |
| : ModulePass (ID), mSkipConstants(pSkipConstants) { |
| } |
| |
| void getAnalysisUsage(llvm::AnalysisUsage &AU) const override { |
| // This pass does not use any other analysis passes, but it does |
| // add new global variables. |
| } |
| |
| bool runOnModule(llvm::Module &M) override { |
| std::vector<llvm::Constant *> GVAddresses; |
| std::vector<llvm::Constant *> GVNames; |
| std::vector<std::string> GVNameStrings; |
| std::vector<uint32_t> GVSizes32; |
| std::vector<uint64_t> GVSizes64; |
| std::vector<uint32_t> GVProperties; |
| |
| const llvm::DataLayout &DL = M.getDataLayout(); |
| const size_t PointerSizeInBits = DL.getPointerSizeInBits(); |
| |
| bccAssert(PointerSizeInBits == 32 || PointerSizeInBits == 64); |
| |
| int GlobalNumber = 0; |
| |
| // i8* - LLVM uses this to represent void* and char* |
| llvm::Type *VoidPtrTy = llvm::Type::getInt8PtrTy(M.getContext()); |
| |
| // i32 |
| llvm::Type *Int32Ty = llvm::Type::getInt32Ty(M.getContext()); |
| |
| // i32 or i64 depending on our actual size_t |
| llvm::Type *SizeTy = llvm::Type::getIntNTy(M.getContext(), |
| PointerSizeInBits); |
| |
| for (auto &GV : M.globals()) { |
| // Skip constant variables if we were configured to do so. |
| if (mSkipConstants && GV.isConstant()) { |
| continue; |
| } |
| |
| // Skip intrinsic variables. |
| if (GV.getName().startswith("llvm.")) { |
| continue; |
| } |
| |
| // In LLVM, an instance of GlobalVariable is actually a Value |
| // corresponding to the address of it. |
| GVAddresses.push_back(llvm::ConstantExpr::getBitCast(&GV, VoidPtrTy)); |
| GVNameStrings.push_back(GV.getName()); |
| |
| // Since these are all global variables, their type is actually a |
| // pointer to the underlying data. We can extract the total underlying |
| // storage size by looking at the first contained type. |
| auto GlobalType = GV.getType()->getPointerElementType(); |
| auto TypeSize = DL.getTypeAllocSize(GlobalType); |
| if (PointerSizeInBits == 32) { |
| GVSizes32.push_back(TypeSize); |
| } else { |
| GVSizes64.push_back(TypeSize); |
| } |
| |
| GVProperties.push_back(getEncodedProperties(GV)); |
| } |
| |
| // Create the new strings for storing the names of the global variables. |
| // This has to be done as a separate pass (over the original global |
| // variables), because these strings are new global variables themselves. |
| for (const auto &GVN : GVNameStrings) { |
| llvm::Constant *C = |
| llvm::ConstantDataArray::getString(M.getContext(), GVN); |
| std::stringstream VarName; |
| VarName << ".rs.name_str_" << GlobalNumber++; |
| llvm::Value *V = M.getOrInsertGlobal(VarName.str(), C->getType()); |
| llvm::GlobalVariable *VarAsStr = llvm::dyn_cast<llvm::GlobalVariable>(V); |
| VarAsStr->setInitializer(C); |
| VarAsStr->setConstant(true); |
| VarAsStr->setLinkage(llvm::GlobalValue::PrivateLinkage); |
| VarAsStr->setUnnamedAddr(llvm::GlobalValue::UnnamedAddr::Global); |
| // VarAsStr has type [_ x i8]*. Cast to i8* for storing in |
| // .rs.global_names. |
| GVNames.push_back(llvm::ConstantExpr::getBitCast(VarAsStr, VoidPtrTy)); |
| } |
| |
| if (PointerSizeInBits == 32) { |
| bccAssert(GVAddresses.size() == GVSizes32.size()); |
| bccAssert(GVSizes64.size() == 0); |
| bccAssert(GVAddresses.size() == GVProperties.size()); |
| } else { |
| bccAssert(GVSizes32.size() == 0); |
| bccAssert(GVAddresses.size() == GVSizes64.size()); |
| bccAssert(GVAddresses.size() == GVProperties.size()); |
| } |
| |
| size_t NumGlobals = GVAddresses.size(); |
| |
| // [NumGlobals * i8*] |
| llvm::ArrayType *VoidPtrArrayTy = llvm::ArrayType::get(VoidPtrTy, |
| NumGlobals); |
| // [NumGlobals * i32] or [NumGlobals * i64] |
| llvm::ArrayType *SizeArrayTy = llvm::ArrayType::get(SizeTy, NumGlobals); |
| |
| // [NumGlobals * i32] |
| llvm::ArrayType *Int32ArrayTy = llvm::ArrayType::get(Int32Ty, NumGlobals); |
| |
| // 1) @.rs.global_entries = constant i32 NumGlobals |
| llvm::Value *V = M.getOrInsertGlobal(kRsGlobalEntries, Int32Ty); |
| llvm::GlobalVariable *GlobalEntries = |
| llvm::dyn_cast<llvm::GlobalVariable>(V); |
| llvm::Constant *GlobalEntriesInit = |
| llvm::ConstantInt::get(Int32Ty, NumGlobals); |
| GlobalEntries->setInitializer(GlobalEntriesInit); |
| GlobalEntries->setConstant(true); |
| |
| // 2) @.rs.global_names = constant [N * i8*] [...] |
| V = M.getOrInsertGlobal(kRsGlobalNames, VoidPtrArrayTy); |
| llvm::GlobalVariable *GlobalNames = |
| llvm::dyn_cast<llvm::GlobalVariable>(V); |
| llvm::Constant *GlobalNamesInit = |
| llvm::ConstantArray::get(VoidPtrArrayTy, GVNames); |
| GlobalNames->setInitializer(GlobalNamesInit); |
| GlobalNames->setConstant(true); |
| |
| // 3) @.rs.global_addresses = constant [N * i8*] [...] |
| V = M.getOrInsertGlobal(kRsGlobalAddresses, VoidPtrArrayTy); |
| llvm::GlobalVariable *GlobalAddresses = |
| llvm::dyn_cast<llvm::GlobalVariable>(V); |
| llvm::Constant *GlobalAddressesInit = |
| llvm::ConstantArray::get(VoidPtrArrayTy, GVAddresses); |
| GlobalAddresses->setInitializer(GlobalAddressesInit); |
| GlobalAddresses->setConstant(true); |
| |
| |
| // 4) @.rs.global_sizes = constant [N * i32 or i64] [...] |
| V = M.getOrInsertGlobal(kRsGlobalSizes, SizeArrayTy); |
| llvm::GlobalVariable *GlobalSizes = |
| llvm::dyn_cast<llvm::GlobalVariable>(V); |
| llvm::Constant *GlobalSizesInit; |
| if (PointerSizeInBits == 32) { |
| GlobalSizesInit = llvm::ConstantDataArray::get(M.getContext(), GVSizes32); |
| } else { |
| GlobalSizesInit = llvm::ConstantDataArray::get(M.getContext(), GVSizes64); |
| } |
| GlobalSizes->setInitializer(GlobalSizesInit); |
| GlobalSizes->setConstant(true); |
| |
| // 5) @.rs.global_properties = constant i32 NumGlobals |
| V = M.getOrInsertGlobal(kRsGlobalProperties, Int32ArrayTy); |
| llvm::GlobalVariable *GlobalProperties = |
| llvm::dyn_cast<llvm::GlobalVariable>(V); |
| llvm::Constant *GlobalPropertiesInit = |
| llvm::ConstantDataArray::get(M.getContext(), GVProperties); |
| GlobalProperties->setInitializer(GlobalPropertiesInit); |
| GlobalProperties->setConstant(true); |
| |
| if (kDebugGlobalInfo) { |
| GlobalEntries->dump(); |
| GlobalNames->dump(); |
| GlobalAddresses->dump(); |
| GlobalSizes->dump(); |
| GlobalProperties->dump(); |
| } |
| |
| // Upon completion, this pass has always modified the Module. |
| return true; |
| } |
| }; |
| |
| } |
| |
| char RSGlobalInfoPass::ID = 0; |
| |
| static llvm::RegisterPass<RSGlobalInfoPass> X("embed-rs-global-info", |
| "Embed additional information about RenderScript global variables"); |
| |
| namespace bcc { |
| |
| llvm::ModulePass * createRSGlobalInfoPass(bool pSkipConstants) { |
| return new RSGlobalInfoPass(pSkipConstants); |
| } |
| |
| } |