From c02a0aabb570b4451041dc22bdab5488ea9b6b99 Mon Sep 17 00:00:00 2001 From: Bill Wendling Date: Mon, 22 Jul 2013 20:15:21 +0000 Subject: [PATCH] Recommit r186217 with testcase fix: Use the function attributes to pass along the stack protector buffer size. Now that we have robust function attributes, don't use a command line option to specify the stack protecto buffer size. llvm-svn: 186863 --- llvm/include/llvm/CodeGen/CommandFlags.h | 4 ---- llvm/include/llvm/Target/TargetOptions.h | 7 +------ llvm/lib/CodeGen/StackProtector.cpp | 26 +++++++++++++++++++------- llvm/test/DebugInfo/X86/dbg_value_direct.ll | 6 +++--- llvm/tools/llc/llc.cpp | 1 - llvm/tools/lto/LTOModule.cpp | 6 ------ llvm/tools/opt/opt.cpp | 1 - 7 files changed, 23 insertions(+), 28 deletions(-) diff --git a/llvm/include/llvm/CodeGen/CommandFlags.h b/llvm/include/llvm/CodeGen/CommandFlags.h index 9a27661..fd1d67b 100644 --- a/llvm/include/llvm/CodeGen/CommandFlags.h +++ b/llvm/include/llvm/CodeGen/CommandFlags.h @@ -220,8 +220,4 @@ cl::opt StartAfter("start-after", cl::value_desc("pass-name"), cl::init("")); -cl::opt -SSPBufferSize("stack-protector-buffer-size", cl::init(8), - cl::desc("Lower bound for a buffer to be considered for " - "stack protection")); #endif diff --git a/llvm/include/llvm/Target/TargetOptions.h b/llvm/include/llvm/Target/TargetOptions.h index e240a9a..04b2080 100644 --- a/llvm/include/llvm/Target/TargetOptions.h +++ b/llvm/include/llvm/Target/TargetOptions.h @@ -48,7 +48,7 @@ namespace llvm { UseSoftFloat(false), NoZerosInBSS(false), JITEmitDebugInfo(false), JITEmitDebugInfoToDisk(false), GuaranteedTailCallOpt(false), DisableTailCalls(false), - StackAlignmentOverride(0), RealignStack(true), SSPBufferSize(0), + StackAlignmentOverride(0), RealignStack(true), EnableFastISel(false), PositionIndependentExecutable(false), EnableSegmentedStacks(false), UseInitArray(false), TrapFuncName(""), FloatABIType(FloatABI::Default), AllowFPOpFusion(FPOpFusion::Standard) @@ -151,10 +151,6 @@ namespace llvm { /// automatically realigned, if needed. unsigned RealignStack : 1; - /// SSPBufferSize - The minimum size of buffers that will receive stack - /// smashing protection when -fstack-protection is used. - unsigned SSPBufferSize; - /// EnableFastISel - This flag enables fast-path instruction selection /// which trades away generated code quality in favor of reducing /// compile time. @@ -224,7 +220,6 @@ inline bool operator==(const TargetOptions &LHS, ARE_EQUAL(DisableTailCalls) && ARE_EQUAL(StackAlignmentOverride) && ARE_EQUAL(RealignStack) && - ARE_EQUAL(SSPBufferSize) && ARE_EQUAL(EnableFastISel) && ARE_EQUAL(PositionIndependentExecutable) && ARE_EQUAL(EnableSegmentedStacks) && diff --git a/llvm/lib/CodeGen/StackProtector.cpp b/llvm/lib/CodeGen/StackProtector.cpp index 1f673ab..9ec7dac 100644 --- a/llvm/lib/CodeGen/StackProtector.cpp +++ b/llvm/lib/CodeGen/StackProtector.cpp @@ -33,6 +33,7 @@ #include "llvm/Pass.h" #include "llvm/Support/CommandLine.h" #include "llvm/Target/TargetLowering.h" +#include using namespace llvm; STATISTIC(NumFunProtected, "Number of functions protected"); @@ -53,6 +54,10 @@ namespace { DominatorTree *DT; + /// \brief The minimum size of buffers that will receive stack smashing + /// protection when -fstack-protection is used. + unsigned SSPBufferSize; + /// VisitedPHIs - The set of PHI nodes visited when determining /// if a variable's reference has been taken. This set /// is maintained to ensure we don't visit the same PHI node multiple @@ -85,11 +90,12 @@ namespace { bool RequiresStackProtector(); public: static char ID; // Pass identification, replacement for typeid. - StackProtector() : FunctionPass(ID), TM(0), TLI(0) { + StackProtector() : FunctionPass(ID), TM(0), TLI(0), SSPBufferSize(0) { initializeStackProtectorPass(*PassRegistry::getPassRegistry()); } StackProtector(const TargetMachine *TM) - : FunctionPass(ID), TM(TM), TLI(0), Trip(TM->getTargetTriple()) { + : FunctionPass(ID), TM(TM), TLI(0), Trip(TM->getTargetTriple()), + SSPBufferSize(8) { initializeStackProtectorPass(*PassRegistry::getPassRegistry()); } @@ -117,6 +123,12 @@ bool StackProtector::runOnFunction(Function &Fn) { if (!RequiresStackProtector()) return false; + Attribute Attr = + Fn.getAttributes().getAttribute(AttributeSet::FunctionIndex, + "stack-protector-buffer-size"); + if (Attr.isStringAttribute()) + SSPBufferSize = atoi(Attr.getValueAsString().data()); + ++NumFunProtected; return InsertStackProtectors(); } @@ -132,7 +144,6 @@ bool StackProtector::ContainsProtectableArray(Type *Ty, bool Strong, // protector if (Strong) return true; - const TargetMachine &TM = TLI->getTargetMachine(); if (!AT->getElementType()->isIntegerTy(8)) { // If we're on a non-Darwin platform or we're inside of a structure, don't // add stack protectors unless the array is a character array. @@ -142,7 +153,7 @@ bool StackProtector::ContainsProtectableArray(Type *Ty, bool Strong, // If an array has more than SSPBufferSize bytes of allocated space, then we // emit stack protectors. - if (TM.Options.SSPBufferSize <= TLI->getDataLayout()->getTypeAllocSize(AT)) + if (SSPBufferSize <= TLI->getDataLayout()->getTypeAllocSize(AT)) return true; } @@ -230,13 +241,14 @@ bool StackProtector::RequiresStackProtector() { if (const ConstantInt *CI = dyn_cast(AI->getArraySize())) { - unsigned BufferSize = TLI->getTargetMachine().Options.SSPBufferSize; - if (CI->getLimitedValue(BufferSize) >= BufferSize) + if (CI->getLimitedValue(SSPBufferSize) >= SSPBufferSize) // A call to alloca with size >= SSPBufferSize requires // stack protectors. return true; - } else // A call to alloca with a variable size requires protectors. + } else { + // A call to alloca with a variable size requires protectors. return true; + } } if (ContainsProtectableArray(AI->getAllocatedType(), Strong)) diff --git a/llvm/test/DebugInfo/X86/dbg_value_direct.ll b/llvm/test/DebugInfo/X86/dbg_value_direct.ll index f095ece..9a40d59 100644 --- a/llvm/test/DebugInfo/X86/dbg_value_direct.ll +++ b/llvm/test/DebugInfo/X86/dbg_value_direct.ll @@ -1,4 +1,4 @@ -; RUN: llc -filetype=obj -O0 -stack-protector-buffer-size=1 < %s +; RUN: llc -filetype=obj -O0 < %s ; Test that we handle DBG_VALUEs in a register without crashing. ; ; Generated from clang with -fsanitize=address: @@ -23,7 +23,7 @@ target triple = "x86_64-unknown-linux-gnu" @__asan_gen_ = private unnamed_addr constant [16 x i8] c"1 32 4 5 .addr \00", align 1 ; Function Attrs: sanitize_address uwtable -define void @_Z4funci(%struct.A* noalias sret %agg.result, i32) #0 { +define void @_Z4funci(%struct.A* noalias sret %agg.result, i32) #0 "stack-protector-buffer-size"="1" { entry: %MyAlloca = alloca [96 x i8], align 32 %1 = ptrtoint [96 x i8]* %MyAlloca to i64 @@ -89,7 +89,7 @@ declare void @llvm.dbg.declare(metadata, metadata) #1 declare void @_ZN1AC1Ev(%struct.A*) #2 -define internal void @asan.module_ctor() { +define internal void @asan.module_ctor() "stack-protector-buffer-size"="1" { call void @__asan_init_v3() %1 = load volatile i64* @__asan_mapping_offset %2 = load volatile i64* @__asan_mapping_scale diff --git a/llvm/tools/llc/llc.cpp b/llvm/tools/llc/llc.cpp index b5852aa..b62f41a 100644 --- a/llvm/tools/llc/llc.cpp +++ b/llvm/tools/llc/llc.cpp @@ -281,7 +281,6 @@ static int compileModule(char **argv, LLVMContext &Context) { Options.PositionIndependentExecutable = EnablePIE; Options.EnableSegmentedStacks = SegmentedStacks; Options.UseInitArray = UseInitArray; - Options.SSPBufferSize = SSPBufferSize; OwningPtr target(TheTarget->createTargetMachine(TheTriple.getTriple(), diff --git a/llvm/tools/lto/LTOModule.cpp b/llvm/tools/lto/LTOModule.cpp index 6220dd1..5ee43ba 100644 --- a/llvm/tools/lto/LTOModule.cpp +++ b/llvm/tools/lto/LTOModule.cpp @@ -151,11 +151,6 @@ UseInitArray("use-init-array", cl::desc("Use .init_array instead of .ctors."), cl::init(false)); -static cl::opt -SSPBufferSize("stack-protector-buffer-size", cl::init(8), - cl::desc("Lower bound for a buffer to be considered for " - "stack protection")); - LTOModule::LTOModule(llvm::Module *m, llvm::TargetMachine *t) : _module(m), _target(t), _context(_target->getMCAsmInfo(), _target->getRegisterInfo(), NULL), @@ -261,7 +256,6 @@ void LTOModule::getTargetOptions(TargetOptions &Options) { Options.PositionIndependentExecutable = EnablePIE; Options.EnableSegmentedStacks = SegmentedStacks; Options.UseInitArray = UseInitArray; - Options.SSPBufferSize = SSPBufferSize; } LTOModule *LTOModule::makeLTOModule(MemoryBuffer *buffer, diff --git a/llvm/tools/opt/opt.cpp b/llvm/tools/opt/opt.cpp index bb8d143e..23acefa 100644 --- a/llvm/tools/opt/opt.cpp +++ b/llvm/tools/opt/opt.cpp @@ -510,7 +510,6 @@ static TargetOptions GetTargetOptions() { Options.PositionIndependentExecutable = EnablePIE; Options.EnableSegmentedStacks = SegmentedStacks; Options.UseInitArray = UseInitArray; - Options.SSPBufferSize = SSPBufferSize; return Options; } -- 2.7.4