diff options
| -rw-r--r-- | include/llvm/InitializePasses.h | 1 | ||||
| -rw-r--r-- | include/llvm/Transforms/NaCl.h | 21 | ||||
| -rw-r--r-- | lib/Transforms/CMakeLists.txt | 1 | ||||
| -rw-r--r-- | lib/Transforms/LLVMBuild.txt | 2 | ||||
| -rw-r--r-- | lib/Transforms/Makefile | 2 | ||||
| -rw-r--r-- | lib/Transforms/NaCl/CMakeLists.txt | 5 | ||||
| -rw-r--r-- | lib/Transforms/NaCl/ExpandCtors.cpp | 143 | ||||
| -rw-r--r-- | lib/Transforms/NaCl/LLVMBuild.txt | 23 | ||||
| -rw-r--r-- | lib/Transforms/NaCl/Makefile | 15 | ||||
| -rw-r--r-- | test/Transforms/NaCl/expand-ctors-empty.ll | 11 | ||||
| -rw-r--r-- | test/Transforms/NaCl/expand-ctors.ll | 36 | ||||
| -rw-r--r-- | tools/opt/opt.cpp | 1 |
12 files changed, 259 insertions, 2 deletions
diff --git a/include/llvm/InitializePasses.h b/include/llvm/InitializePasses.h index 4c93d480dd..87899fc360 100644 --- a/include/llvm/InitializePasses.h +++ b/include/llvm/InitializePasses.h @@ -261,6 +261,7 @@ void initializeUnpackMachineBundlesPass(PassRegistry&); void initializeFinalizeMachineBundlesPass(PassRegistry&); void initializeBBVectorizePass(PassRegistry&); void initializeMachineFunctionPrinterPassPass(PassRegistry&); +void initializeExpandCtorsPass(PassRegistry&); // @LOCALMOD void initializeNaClCcRewritePass(PassRegistry&); // @LOCALMOD } diff --git a/include/llvm/Transforms/NaCl.h b/include/llvm/Transforms/NaCl.h new file mode 100644 index 0000000000..fe29463a8b --- /dev/null +++ b/include/llvm/Transforms/NaCl.h @@ -0,0 +1,21 @@ +//===-- NaCl.h - NaCl Transformations ---------------------------*- C++ -*-===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// + +#ifndef LLVM_TRANSFORMS_NACL_H +#define LLVM_TRANSFORMS_NACL_H + +namespace llvm { + +class ModulePass; + +ModulePass *createExpandCtorsPass(); + +} + +#endif diff --git a/lib/Transforms/CMakeLists.txt b/lib/Transforms/CMakeLists.txt index de1353e6c1..9fa690971a 100644 --- a/lib/Transforms/CMakeLists.txt +++ b/lib/Transforms/CMakeLists.txt @@ -5,3 +5,4 @@ add_subdirectory(Scalar) add_subdirectory(IPO) add_subdirectory(Vectorize) add_subdirectory(Hello) +add_subdirectory(NaCl) diff --git a/lib/Transforms/LLVMBuild.txt b/lib/Transforms/LLVMBuild.txt index f7bca064c7..001ba5d232 100644 --- a/lib/Transforms/LLVMBuild.txt +++ b/lib/Transforms/LLVMBuild.txt @@ -16,7 +16,7 @@ ;===------------------------------------------------------------------------===; [common] -subdirectories = IPO InstCombine Instrumentation Scalar Utils Vectorize +subdirectories = IPO InstCombine Instrumentation Scalar Utils Vectorize NaCl [component_0] type = Group diff --git a/lib/Transforms/Makefile b/lib/Transforms/Makefile index fb6fa26f11..ae03ff32c5 100644 --- a/lib/Transforms/Makefile +++ b/lib/Transforms/Makefile @@ -8,7 +8,7 @@ ##===----------------------------------------------------------------------===## LEVEL = ../.. -PARALLEL_DIRS = Utils Instrumentation Scalar InstCombine IPO Vectorize Hello +PARALLEL_DIRS = Utils Instrumentation Scalar InstCombine IPO Vectorize Hello NaCl ifeq ($(NACL_SANDBOX),1) PARALLEL_DIRS := $(filter-out Hello, $(PARALLEL_DIRS)) diff --git a/lib/Transforms/NaCl/CMakeLists.txt b/lib/Transforms/NaCl/CMakeLists.txt new file mode 100644 index 0000000000..d634ad9655 --- /dev/null +++ b/lib/Transforms/NaCl/CMakeLists.txt @@ -0,0 +1,5 @@ +add_llvm_library(LLVMTransformsNaCl + ExpandCtors.cpp + ) + +add_dependencies(LLVMTransformsNaCl intrinsics_gen) diff --git a/lib/Transforms/NaCl/ExpandCtors.cpp b/lib/Transforms/NaCl/ExpandCtors.cpp new file mode 100644 index 0000000000..9c5f2cd2d7 --- /dev/null +++ b/lib/Transforms/NaCl/ExpandCtors.cpp @@ -0,0 +1,143 @@ +//===- ExpandCtors.cpp - Convert ctors/dtors to concrete arrays -----------===// +// +// The LLVM Compiler Infrastructure +// +// This file is distributed under the University of Illinois Open Source +// License. See LICENSE.TXT for details. +// +//===----------------------------------------------------------------------===// +// +// This pass converts LLVM's special symbols llvm.global_ctors and +// llvm.global_dtors to concrete arrays, __init_array_start/end and +// __fini_array_start/end, that are usable by a C library. +// +// This pass sorts the contents of global_ctors/dtors according to the +// priority values they contain and removes the priority values. +// +//===----------------------------------------------------------------------===// + +#include <vector> + +#include "llvm/Constants.h" +#include "llvm/DerivedTypes.h" +#include "llvm/Instructions.h" +#include "llvm/Module.h" +#include "llvm/Pass.h" +#include "llvm/Support/raw_ostream.h" +#include "llvm/Transforms/NaCl.h" +#include "llvm/TypeBuilder.h" + +using namespace llvm; + +namespace { + struct ExpandCtors : public ModulePass { + static char ID; // Pass identification, replacement for typeid + ExpandCtors() : ModulePass(ID) { + initializeExpandCtorsPass(*PassRegistry::getPassRegistry()); + } + + virtual bool runOnModule(Module &M); + }; +} + +char ExpandCtors::ID = 0; +INITIALIZE_PASS(ExpandCtors, "nacl-expand-ctors", + "Hook up constructor and destructor arrays to libc", + false, false) + +static void setGlobalVariableValue(Module &M, const char *Name, + Constant *Value) { + GlobalVariable *Var = M.getNamedGlobal(Name); + if (!Var) { + // This warning can happen in a program that does not use a libc + // and so does not call the functions in __init_array_start or + // __fini_array_end. Such a program might be linked with + // "-nostdlib". + errs() << "Warning: Variable " << Name << " not referenced\n"; + } else { + if (Var->hasInitializer()) { + report_fatal_error(std::string("Variable ") + Name + + " already has an initializer"); + } + Var->replaceAllUsesWith(ConstantExpr::getBitCast(Value, Var->getType())); + Var->eraseFromParent(); + } +} + +struct FuncArrayEntry { + uint64_t priority; + Constant *func; +}; + +static bool compareEntries(FuncArrayEntry Entry1, FuncArrayEntry Entry2) { + return Entry1.priority < Entry2.priority; +} + +static void defineFuncArray(Module &M, const char *LlvmArrayName, + const char *StartSymbol, + const char *EndSymbol) { + std::vector<Constant*> Funcs; + + GlobalVariable *Array = M.getNamedGlobal(LlvmArrayName); + if (Array && Array->hasInitializer()) { + ConstantArray *InitList = cast<ConstantArray>(Array->getInitializer()); + std::vector<FuncArrayEntry> FuncsToSort; + for (unsigned Index = 0; Index < InitList->getNumOperands(); ++Index) { + ConstantStruct *CS = cast<ConstantStruct>(InitList->getOperand(Index)); + FuncArrayEntry Entry; + Entry.priority = cast<ConstantInt>(CS->getOperand(0))->getZExtValue(); + Entry.func = CS->getOperand(1); + FuncsToSort.push_back(Entry); + } + + std::sort(FuncsToSort.begin(), FuncsToSort.end(), compareEntries); + for (std::vector<FuncArrayEntry>::iterator Iter = FuncsToSort.begin(); + Iter != FuncsToSort.end(); + ++Iter) { + Funcs.push_back(Iter->func); + } + // No code should be referencing global_ctors/global_dtors, + // because this symbol is internal to LLVM. + Array->eraseFromParent(); + } + + Type *FuncTy = FunctionType::get(Type::getVoidTy(M.getContext()), false); + Type *FuncPtrTy = FuncTy->getPointerTo(); + ArrayType *ArrayTy = ArrayType::get(FuncPtrTy, Funcs.size()); + GlobalVariable *NewArray = + new GlobalVariable(M, ArrayTy, /* isConstant= */ true, + GlobalValue::InternalLinkage, + ConstantArray::get(ArrayTy, Funcs)); + setGlobalVariableValue(M, StartSymbol, NewArray); + // We do this last so that LLVM gives NewArray the name + // "__{init,fini}_array_start" without adding any suffixes to + // disambiguate from the original GlobalVariable's name. This is + // not essential -- it just makes the output easier to understand + // when looking at symbols for debugging. + NewArray->setName(StartSymbol); + + // We replace "__{init,fini}_array_end" with the address of the end + // of NewArray. This removes the name "__{init,fini}_array_end" + // from the output, which is not ideal for debugging. Ideally we + // would convert "__{init,fini}_array_end" to being a GlobalAlias + // that points to the end of the array. However, unfortunately LLVM + // does not generate correct code when a GlobalAlias contains a + // GetElementPtr ConstantExpr. + Constant *NewArrayEnd = + ConstantExpr::getGetElementPtr(NewArray, + ConstantInt::get(M.getContext(), + APInt(32, 1))); + setGlobalVariableValue(M, EndSymbol, NewArrayEnd); +} + +bool ExpandCtors::runOnModule(Module &M) { + defineFuncArray(M, "llvm.global_ctors", + "__init_array_start", "__init_array_end"); + defineFuncArray(M, "llvm.global_dtors", + "__fini_array_start", "__fini_array_end"); + return true; +} + +ModulePass *llvm::createExpandCtorsPass() { + return new ExpandCtors(); +} diff --git a/lib/Transforms/NaCl/LLVMBuild.txt b/lib/Transforms/NaCl/LLVMBuild.txt new file mode 100644 index 0000000000..2f1522b3e5 --- /dev/null +++ b/lib/Transforms/NaCl/LLVMBuild.txt @@ -0,0 +1,23 @@ +;===- ./lib/Transforms/NaCl/LLVMBuild.txt ----------------------*- Conf -*--===; +; +; The LLVM Compiler Infrastructure +; +; This file is distributed under the University of Illinois Open Source +; License. See LICENSE.TXT for details. +; +;===------------------------------------------------------------------------===; +; +; This is an LLVMBuild description file for the components in this subdirectory. +; +; For more information on the LLVMBuild system, please see: +; +; http://llvm.org/docs/LLVMBuild.html +; +;===------------------------------------------------------------------------===; + +[component_0] +type = Library +name = NaCl +parent = Transforms +library_name = NaCl +required_libraries = Core diff --git a/lib/Transforms/NaCl/Makefile b/lib/Transforms/NaCl/Makefile new file mode 100644 index 0000000000..ecf8db6eae --- /dev/null +++ b/lib/Transforms/NaCl/Makefile @@ -0,0 +1,15 @@ +##===- lib/Transforms/NaCl/Makefile-------------------------*- Makefile -*-===## +# +# The LLVM Compiler Infrastructure +# +# This file is distributed under the University of Illinois Open Source +# License. See LICENSE.TXT for details. +# +##===----------------------------------------------------------------------===## + +LEVEL = ../../.. +LIBRARYNAME = LLVMTransformsNaCl +BUILD_ARCHIVE = 1 + +include $(LEVEL)/Makefile.common + diff --git a/test/Transforms/NaCl/expand-ctors-empty.ll b/test/Transforms/NaCl/expand-ctors-empty.ll new file mode 100644 index 0000000000..4368270765 --- /dev/null +++ b/test/Transforms/NaCl/expand-ctors-empty.ll @@ -0,0 +1,11 @@ +; Currently we do not define __{init,fini}_array_end as named aliases. +; RUN: opt < %s -nacl-expand-ctors -S | not grep __init_array_end +; RUN: opt < %s -nacl-expand-ctors -S | not grep __fini_array_end + +; RUN: opt < %s -nacl-expand-ctors -S | FileCheck %s + +; If llvm.global_ctors is not present, it is treated as if it is an +; empty array, and __{init,fini}_array_start are defined anyway. + +; CHECK: @__init_array_start = internal constant [0 x void ()*] zeroinitializer +; CHECK: @__fini_array_start = internal constant [0 x void ()*] zeroinitializer diff --git a/test/Transforms/NaCl/expand-ctors.ll b/test/Transforms/NaCl/expand-ctors.ll new file mode 100644 index 0000000000..7f202618e7 --- /dev/null +++ b/test/Transforms/NaCl/expand-ctors.ll @@ -0,0 +1,36 @@ +; We expect these symbol names to be removed: +; RUN: opt < %s -nacl-expand-ctors -S | not grep llvm.global_ctors +; RUN: opt < %s -nacl-expand-ctors -S | not grep __init_array_end +; RUN: opt < %s -nacl-expand-ctors -S | not grep __fini_array_end + +; RUN: opt < %s -nacl-expand-ctors -S | FileCheck %s + +@llvm.global_ctors = appending global [3 x { i32, void ()* }] + [{ i32, void ()* } { i32 300, void ()* @init_func_A }, + { i32, void ()* } { i32 100, void ()* @init_func_B }, + { i32, void ()* } { i32 200, void ()* @init_func_C }] + +@__init_array_start = extern_weak global [0 x void ()*] +@__init_array_end = extern_weak global [0 x void ()*] + +; CHECK: @__init_array_start = internal constant [3 x void ()*] [void ()* @init_func_B, void ()* @init_func_C, void ()* @init_func_A] +; CHECK: @__fini_array_start = internal constant [0 x void ()*] zeroinitializer + +define void @init_func_A() { ret void } +define void @init_func_B() { ret void } +define void @init_func_C() { ret void } + +define [0 x void ()*]* @get_array_start() { + ret [0 x void ()*]* @__init_array_start; +} +; CHECK: @get_array_start() +; CHECK: ret {{.*}} @__init_array_start + +define [0 x void ()*]* @get_array_end() { + ret [0 x void ()*]* @__init_array_end; +} + +; @get_array_end() is converted to use a GetElementPtr that returns +; the end of the generated array: +; CHECK: @get_array_end() +; CHECK: ret {{.*}} bitcast ([3 x void ()*]* getelementptr inbounds ([3 x void ()*]* @__init_array_start, i32 1) diff --git a/tools/opt/opt.cpp b/tools/opt/opt.cpp index 7ecd25c6b7..4a8041d2a0 100644 --- a/tools/opt/opt.cpp +++ b/tools/opt/opt.cpp @@ -504,6 +504,7 @@ int main(int argc, char **argv) { initializeInstCombine(Registry); initializeInstrumentation(Registry); initializeTarget(Registry); + initializeExpandCtorsPass(Registry); cl::ParseCommandLineOptions(argc, argv, "llvm .bc -> .bc modular optimizer and analysis printer\n"); |