[llvm] r239761 - Protection against stack-based memory corruption errors using SafeStack
Pete Cooper
peter_cooper at apple.com
Mon Jun 15 15:29:08 PDT 2015
Great. Thanks very much!
Pete
> On Jun 15, 2015, at 3:22 PM, Peter Collingbourne <peter at pcc.me.uk> wrote:
>
> Done in r239772, which also includes a few corrections to that enum.
>
> Peter
>
> On Mon, Jun 15, 2015 at 02:31:28PM -0700, Pete Cooper wrote:
>> Hey Peter
>>
>> You probably want to add your attribute to include/llvm-c/Core.h at the bottom of the LLVMAttribute enum.
>>
>> I know this means just adding it to a commented out FIXME, but probably best to have it there for completeness.
>>
>> Also, as safestack is only allowed on function attributes, can you please add a test which verifies we throw errors at parsing time if it is attached to either a return or parameter attribute.
>>
>> Cheers,
>> Pete
>>> On Jun 15, 2015, at 2:07 PM, Peter Collingbourne <peter at pcc.me.uk> wrote:
>>>
>>> Author: pcc
>>> Date: Mon Jun 15 16:07:11 2015
>>> New Revision: 239761
>>>
>>> URL: http://llvm.org/viewvc/llvm-project?rev=239761&view=rev
>>> Log:
>>> Protection against stack-based memory corruption errors using SafeStack
>>>
>>> This patch adds the safe stack instrumentation pass to LLVM, which separates
>>> the program stack into a safe stack, which stores return addresses, register
>>> spills, and local variables that are statically verified to be accessed
>>> in a safe way, and the unsafe stack, which stores everything else. Such
>>> separation makes it much harder for an attacker to corrupt objects on the
>>> safe stack, including function pointers stored in spilled registers and
>>> return addresses. You can find more information about the safe stack, as
>>> well as other parts of or control-flow hijack protection technique in our
>>> OSDI paper on code-pointer integrity (http://dslab.epfl.ch/pubs/cpi.pdf)
>>> and our project website (http://levee.epfl.ch).
>>>
>>> The overhead of our implementation of the safe stack is very close to zero
>>> (0.01% on the Phoronix benchmarks). This is lower than the overhead of
>>> stack cookies, which are supported by LLVM and are commonly used today,
>>> yet the security guarantees of the safe stack are strictly stronger than
>>> stack cookies. In some cases, the safe stack improves performance due to
>>> better cache locality.
>>>
>>> Our current implementation of the safe stack is stable and robust, we
>>> used it to recompile multiple projects on Linux including Chromium, and
>>> we also recompiled the entire FreeBSD user-space system and more than 100
>>> packages. We ran unit tests on the FreeBSD system and many of the packages
>>> and observed no errors caused by the safe stack. The safe stack is also fully
>>> binary compatible with non-instrumented code and can be applied to parts of
>>> a program selectively.
>>>
>>> This patch is our implementation of the safe stack on top of LLVM. The
>>> patches make the following changes:
>>>
>>> - Add the safestack function attribute, similar to the ssp, sspstrong and
>>> sspreq attributes.
>>>
>>> - Add the SafeStack instrumentation pass that applies the safe stack to all
>>> functions that have the safestack attribute. This pass moves all unsafe local
>>> variables to the unsafe stack with a separate stack pointer, whereas all
>>> safe variables remain on the regular stack that is managed by LLVM as usual.
>>>
>>> - Invoke the pass as the last stage before code generation (at the same time
>>> the existing cookie-based stack protector pass is invoked).
>>>
>>> - Add unit tests for the safe stack.
>>>
>>> Original patch by Volodymyr Kuznetsov and others at the Dependable Systems
>>> Lab at EPFL; updates and upstreaming by myself.
>>>
>>> Differential Revision: http://reviews.llvm.org/D6094
>>>
>>> Added:
>>> llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp
>>> llvm/trunk/test/Transforms/SafeStack/
>>> llvm/trunk/test/Transforms/SafeStack/addr-taken.ll
>>> llvm/trunk/test/Transforms/SafeStack/array-aligned.ll
>>> llvm/trunk/test/Transforms/SafeStack/array.ll
>>> llvm/trunk/test/Transforms/SafeStack/call.ll
>>> llvm/trunk/test/Transforms/SafeStack/cast.ll
>>> llvm/trunk/test/Transforms/SafeStack/constant-gep-call.ll
>>> llvm/trunk/test/Transforms/SafeStack/constant-gep.ll
>>> llvm/trunk/test/Transforms/SafeStack/constant-geps.ll
>>> llvm/trunk/test/Transforms/SafeStack/dynamic-alloca.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-addr-pointer.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store2.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-call.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-casted-pointer.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-gep-call.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-gep-invoke.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-gep-negative.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-gep-ptrtoint.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-gep-store.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-phi-call.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-select-call.ll
>>> llvm/trunk/test/Transforms/SafeStack/escape-vector.ll
>>> llvm/trunk/test/Transforms/SafeStack/invoke.ll
>>> llvm/trunk/test/Transforms/SafeStack/no-attr.ll
>>> llvm/trunk/test/Transforms/SafeStack/phi-cycle.ll
>>> llvm/trunk/test/Transforms/SafeStack/setjmp.ll
>>> llvm/trunk/test/Transforms/SafeStack/setjmp2.ll
>>> llvm/trunk/test/Transforms/SafeStack/struct.ll
>>> Modified:
>>> llvm/trunk/docs/LangRef.rst
>>> llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h
>>> llvm/trunk/include/llvm/IR/Attributes.h
>>> llvm/trunk/include/llvm/InitializePasses.h
>>> llvm/trunk/include/llvm/LinkAllPasses.h
>>> llvm/trunk/include/llvm/Transforms/Instrumentation.h
>>> llvm/trunk/lib/AsmParser/LLLexer.cpp
>>> llvm/trunk/lib/AsmParser/LLParser.cpp
>>> llvm/trunk/lib/AsmParser/LLToken.h
>>> llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp
>>> llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp
>>> llvm/trunk/lib/CodeGen/LLVMBuild.txt
>>> llvm/trunk/lib/CodeGen/Passes.cpp
>>> llvm/trunk/lib/IR/Attributes.cpp
>>> llvm/trunk/lib/IR/Verifier.cpp
>>> llvm/trunk/lib/Target/CppBackend/CPPBackend.cpp
>>> llvm/trunk/lib/Transforms/IPO/Inliner.cpp
>>> llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt
>>> llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp
>>>
>>> Modified: llvm/trunk/docs/LangRef.rst
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/docs/LangRef.rst?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/docs/LangRef.rst (original)
>>> +++ llvm/trunk/docs/LangRef.rst Mon Jun 15 16:07:11 2015
>>> @@ -1319,6 +1319,15 @@ example:
>>> ``setjmp`` is an example of such a function. The compiler disables
>>> some optimizations (like tail calls) in the caller of these
>>> functions.
>>> +``safestack``
>>> + This attribute indicates that
>>> + `SafeStack <http://clang.llvm.org/docs/SafeStack.html>`_
>>> + protection is enabled for this function.
>>> +
>>> + If a function that has a ``safestack`` attribute is inlined into a
>>> + function that doesn't have a ``safestack`` attribute or which has an
>>> + ``ssp``, ``sspstrong`` or ``sspreq`` attribute, then the resulting
>>> + function will have a ``safestack`` attribute.
>>> ``sanitize_address``
>>> This attribute indicates that AddressSanitizer checks
>>> (dynamic address safety analysis) are enabled for this function.
>>>
>>> Modified: llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h (original)
>>> +++ llvm/trunk/include/llvm/Bitcode/LLVMBitCodes.h Mon Jun 15 16:07:11 2015
>>> @@ -403,7 +403,8 @@ namespace bitc {
>>> ATTR_KIND_JUMP_TABLE = 40,
>>> ATTR_KIND_DEREFERENCEABLE = 41,
>>> ATTR_KIND_DEREFERENCEABLE_OR_NULL = 42,
>>> - ATTR_KIND_CONVERGENT = 43
>>> + ATTR_KIND_CONVERGENT = 43,
>>> + ATTR_KIND_SAFESTACK = 44,
>>> };
>>>
>>> enum ComdatSelectionKindCodes {
>>>
>>> Modified: llvm/trunk/include/llvm/IR/Attributes.h
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/IR/Attributes.h?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/include/llvm/IR/Attributes.h (original)
>>> +++ llvm/trunk/include/llvm/IR/Attributes.h Mon Jun 15 16:07:11 2015
>>> @@ -108,6 +108,7 @@ public:
>>> StackProtect, ///< Stack protection.
>>> StackProtectReq, ///< Stack protection required.
>>> StackProtectStrong, ///< Strong Stack protection.
>>> + SafeStack, ///< Safe Stack protection.
>>> StructRet, ///< Hidden pointer to structure to return
>>> SanitizeAddress, ///< AddressSanitizer is on.
>>> SanitizeThread, ///< ThreadSanitizer is on.
>>>
>>> Modified: llvm/trunk/include/llvm/InitializePasses.h
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/InitializePasses.h?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/include/llvm/InitializePasses.h (original)
>>> +++ llvm/trunk/include/llvm/InitializePasses.h Mon Jun 15 16:07:11 2015
>>> @@ -242,6 +242,7 @@ void initializeRegionOnlyViewerPass(Pass
>>> void initializeRegionPrinterPass(PassRegistry&);
>>> void initializeRegionViewerPass(PassRegistry&);
>>> void initializeRewriteStatepointsForGCPass(PassRegistry&);
>>> +void initializeSafeStackPass(PassRegistry&);
>>> void initializeSCCPPass(PassRegistry&);
>>> void initializeSROAPass(PassRegistry&);
>>> void initializeSROA_DTPass(PassRegistry&);
>>>
>>> Modified: llvm/trunk/include/llvm/LinkAllPasses.h
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/LinkAllPasses.h?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/include/llvm/LinkAllPasses.h (original)
>>> +++ llvm/trunk/include/llvm/LinkAllPasses.h Mon Jun 15 16:07:11 2015
>>> @@ -131,6 +131,7 @@ namespace {
>>> (void) llvm::createRegionPrinterPass();
>>> (void) llvm::createRegionViewerPass();
>>> (void) llvm::createSCCPPass();
>>> + (void) llvm::createSafeStackPass();
>>> (void) llvm::createScalarReplAggregatesPass();
>>> (void) llvm::createSingleLoopExtractorPass();
>>> (void) llvm::createStripSymbolsPass();
>>>
>>> Modified: llvm/trunk/include/llvm/Transforms/Instrumentation.h
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Transforms/Instrumentation.h?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/include/llvm/Transforms/Instrumentation.h (original)
>>> +++ llvm/trunk/include/llvm/Transforms/Instrumentation.h Mon Jun 15 16:07:11 2015
>>> @@ -132,6 +132,10 @@ inline ModulePass *createDataFlowSanitiz
>>> // checking on loads, stores, and other memory intrinsics.
>>> FunctionPass *createBoundsCheckingPass();
>>>
>>> +/// \brief This pass splits the stack into a safe stack and an unsafe stack to
>>> +/// protect against stack-based overflow vulnerabilities.
>>> +FunctionPass *createSafeStackPass();
>>> +
>>> } // End llvm namespace
>>>
>>> #endif
>>>
>>> Modified: llvm/trunk/lib/AsmParser/LLLexer.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/AsmParser/LLLexer.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/AsmParser/LLLexer.cpp (original)
>>> +++ llvm/trunk/lib/AsmParser/LLLexer.cpp Mon Jun 15 16:07:11 2015
>>> @@ -628,6 +628,7 @@ lltok::Kind LLLexer::LexIdentifier() {
>>> KEYWORD(ssp);
>>> KEYWORD(sspreq);
>>> KEYWORD(sspstrong);
>>> + KEYWORD(safestack);
>>> KEYWORD(sanitize_address);
>>> KEYWORD(sanitize_thread);
>>> KEYWORD(sanitize_memory);
>>>
>>> Modified: llvm/trunk/lib/AsmParser/LLParser.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/AsmParser/LLParser.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/AsmParser/LLParser.cpp (original)
>>> +++ llvm/trunk/lib/AsmParser/LLParser.cpp Mon Jun 15 16:07:11 2015
>>> @@ -958,6 +958,7 @@ bool LLParser::ParseFnAttributeValuePair
>>> case lltok::kw_ssp: B.addAttribute(Attribute::StackProtect); break;
>>> case lltok::kw_sspreq: B.addAttribute(Attribute::StackProtectReq); break;
>>> case lltok::kw_sspstrong: B.addAttribute(Attribute::StackProtectStrong); break;
>>> + case lltok::kw_safestack: B.addAttribute(Attribute::SafeStack); break;
>>> case lltok::kw_sanitize_address: B.addAttribute(Attribute::SanitizeAddress); break;
>>> case lltok::kw_sanitize_thread: B.addAttribute(Attribute::SanitizeThread); break;
>>> case lltok::kw_sanitize_memory: B.addAttribute(Attribute::SanitizeMemory); break;
>>> @@ -1267,6 +1268,7 @@ bool LLParser::ParseOptionalParamAttrs(A
>>> case lltok::kw_ssp:
>>> case lltok::kw_sspreq:
>>> case lltok::kw_sspstrong:
>>> + case lltok::kw_safestack:
>>> case lltok::kw_uwtable:
>>> HaveError |= Error(Lex.getLoc(), "invalid use of function-only attribute");
>>> break;
>>> @@ -1343,6 +1345,7 @@ bool LLParser::ParseOptionalReturnAttrs(
>>> case lltok::kw_ssp:
>>> case lltok::kw_sspreq:
>>> case lltok::kw_sspstrong:
>>> + case lltok::kw_safestack:
>>> case lltok::kw_uwtable:
>>> HaveError |= Error(Lex.getLoc(), "invalid use of function-only attribute");
>>> break;
>>>
>>> Modified: llvm/trunk/lib/AsmParser/LLToken.h
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/AsmParser/LLToken.h?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/AsmParser/LLToken.h (original)
>>> +++ llvm/trunk/lib/AsmParser/LLToken.h Mon Jun 15 16:07:11 2015
>>> @@ -135,6 +135,7 @@ namespace lltok {
>>> kw_ssp,
>>> kw_sspreq,
>>> kw_sspstrong,
>>> + kw_safestack,
>>> kw_sret,
>>> kw_sanitize_thread,
>>> kw_sanitize_memory,
>>>
>>> Modified: llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp (original)
>>> +++ llvm/trunk/lib/Bitcode/Reader/BitcodeReader.cpp Mon Jun 15 16:07:11 2015
>>> @@ -1146,6 +1146,8 @@ static Attribute::AttrKind getAttrFromCo
>>> return Attribute::StackProtectReq;
>>> case bitc::ATTR_KIND_STACK_PROTECT_STRONG:
>>> return Attribute::StackProtectStrong;
>>> + case bitc::ATTR_KIND_SAFESTACK:
>>> + return Attribute::SafeStack;
>>> case bitc::ATTR_KIND_STRUCT_RET:
>>> return Attribute::StructRet;
>>> case bitc::ATTR_KIND_SANITIZE_ADDRESS:
>>>
>>> Modified: llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp (original)
>>> +++ llvm/trunk/lib/Bitcode/Writer/BitcodeWriter.cpp Mon Jun 15 16:07:11 2015
>>> @@ -232,6 +232,8 @@ static uint64_t getAttrKindEncoding(Attr
>>> return bitc::ATTR_KIND_STACK_PROTECT_REQ;
>>> case Attribute::StackProtectStrong:
>>> return bitc::ATTR_KIND_STACK_PROTECT_STRONG;
>>> + case Attribute::SafeStack:
>>> + return bitc::ATTR_KIND_SAFESTACK;
>>> case Attribute::StructRet:
>>> return bitc::ATTR_KIND_STRUCT_RET;
>>> case Attribute::SanitizeAddress:
>>>
>>> Modified: llvm/trunk/lib/CodeGen/LLVMBuild.txt
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/LLVMBuild.txt?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/CodeGen/LLVMBuild.txt (original)
>>> +++ llvm/trunk/lib/CodeGen/LLVMBuild.txt Mon Jun 15 16:07:11 2015
>>> @@ -22,4 +22,4 @@ subdirectories = AsmPrinter SelectionDAG
>>> type = Library
>>> name = CodeGen
>>> parent = Libraries
>>> -required_libraries = Analysis Core MC Scalar Support Target TransformUtils
>>> +required_libraries = Analysis Core Instrumentation MC Scalar Support Target TransformUtils
>>>
>>> Modified: llvm/trunk/lib/CodeGen/Passes.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/Passes.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/CodeGen/Passes.cpp (original)
>>> +++ llvm/trunk/lib/CodeGen/Passes.cpp Mon Jun 15 16:07:11 2015
>>> @@ -24,6 +24,7 @@
>>> #include "llvm/Support/Debug.h"
>>> #include "llvm/Support/ErrorHandling.h"
>>> #include "llvm/Support/raw_ostream.h"
>>> +#include "llvm/Transforms/Instrumentation.h"
>>> #include "llvm/Transforms/Scalar.h"
>>> #include "llvm/Transforms/Utils/SymbolRewriter.h"
>>>
>>> @@ -456,6 +457,9 @@ void TargetPassConfig::addCodeGenPrepare
>>> void TargetPassConfig::addISelPrepare() {
>>> addPreISel();
>>>
>>> + // Add both the safe stack and the stack protection passes: each of them will
>>> + // only protect functions that have corresponding attributes.
>>> + addPass(createSafeStackPass());
>>> addPass(createStackProtectorPass(TM));
>>>
>>> if (PrintISelInput)
>>>
>>> Modified: llvm/trunk/lib/IR/Attributes.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/Attributes.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/IR/Attributes.cpp (original)
>>> +++ llvm/trunk/lib/IR/Attributes.cpp Mon Jun 15 16:07:11 2015
>>> @@ -252,6 +252,8 @@ std::string Attribute::getAsString(bool
>>> return "sspreq";
>>> if (hasAttribute(Attribute::StackProtectStrong))
>>> return "sspstrong";
>>> + if (hasAttribute(Attribute::SafeStack))
>>> + return "safestack";
>>> if (hasAttribute(Attribute::StructRet))
>>> return "sret";
>>> if (hasAttribute(Attribute::SanitizeThread))
>>> @@ -437,6 +439,7 @@ uint64_t AttributeImpl::getAttrMask(Attr
>>> case Attribute::NonNull: return 1ULL << 44;
>>> case Attribute::JumpTable: return 1ULL << 45;
>>> case Attribute::Convergent: return 1ULL << 46;
>>> + case Attribute::SafeStack: return 1ULL << 47;
>>> case Attribute::Dereferenceable:
>>> llvm_unreachable("dereferenceable attribute not supported in raw format");
>>> break;
>>>
>>> Modified: llvm/trunk/lib/IR/Verifier.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/IR/Verifier.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/IR/Verifier.cpp (original)
>>> +++ llvm/trunk/lib/IR/Verifier.cpp Mon Jun 15 16:07:11 2015
>>> @@ -1251,6 +1251,7 @@ void Verifier::VerifyAttributeTypes(Attr
>>> I->getKindAsEnum() == Attribute::StackProtect ||
>>> I->getKindAsEnum() == Attribute::StackProtectReq ||
>>> I->getKindAsEnum() == Attribute::StackProtectStrong ||
>>> + I->getKindAsEnum() == Attribute::SafeStack ||
>>> I->getKindAsEnum() == Attribute::NoRedZone ||
>>> I->getKindAsEnum() == Attribute::NoImplicitFloat ||
>>> I->getKindAsEnum() == Attribute::Naked ||
>>>
>>> Modified: llvm/trunk/lib/Target/CppBackend/CPPBackend.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/CppBackend/CPPBackend.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/Target/CppBackend/CPPBackend.cpp (original)
>>> +++ llvm/trunk/lib/Target/CppBackend/CPPBackend.cpp Mon Jun 15 16:07:11 2015
>>> @@ -513,6 +513,7 @@ void CppWriter::printAttributes(const At
>>> HANDLE_ATTR(StackProtect);
>>> HANDLE_ATTR(StackProtectReq);
>>> HANDLE_ATTR(StackProtectStrong);
>>> + HANDLE_ATTR(SafeStack);
>>> HANDLE_ATTR(NoCapture);
>>> HANDLE_ATTR(NoRedZone);
>>> HANDLE_ATTR(NoImplicitFloat);
>>>
>>> Modified: llvm/trunk/lib/Transforms/IPO/Inliner.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/IPO/Inliner.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/Transforms/IPO/Inliner.cpp (original)
>>> +++ llvm/trunk/lib/Transforms/IPO/Inliner.cpp Mon Jun 15 16:07:11 2015
>>> @@ -93,19 +93,26 @@ static void AdjustCallerSSPLevel(Functio
>>> // clutter to the IR.
>>> AttrBuilder B;
>>> B.addAttribute(Attribute::StackProtect)
>>> - .addAttribute(Attribute::StackProtectStrong);
>>> + .addAttribute(Attribute::StackProtectStrong)
>>> + .addAttribute(Attribute::StackProtectReq);
>>> AttributeSet OldSSPAttr = AttributeSet::get(Caller->getContext(),
>>> AttributeSet::FunctionIndex,
>>> B);
>>>
>>> - if (Callee->hasFnAttribute(Attribute::StackProtectReq)) {
>>> + if (Callee->hasFnAttribute(Attribute::SafeStack)) {
>>> + Caller->removeAttributes(AttributeSet::FunctionIndex, OldSSPAttr);
>>> + Caller->addFnAttr(Attribute::SafeStack);
>>> + } else if (Callee->hasFnAttribute(Attribute::StackProtectReq) &&
>>> + !Caller->hasFnAttribute(Attribute::SafeStack)) {
>>> Caller->removeAttributes(AttributeSet::FunctionIndex, OldSSPAttr);
>>> Caller->addFnAttr(Attribute::StackProtectReq);
>>> } else if (Callee->hasFnAttribute(Attribute::StackProtectStrong) &&
>>> + !Caller->hasFnAttribute(Attribute::SafeStack) &&
>>> !Caller->hasFnAttribute(Attribute::StackProtectReq)) {
>>> Caller->removeAttributes(AttributeSet::FunctionIndex, OldSSPAttr);
>>> Caller->addFnAttr(Attribute::StackProtectStrong);
>>> } else if (Callee->hasFnAttribute(Attribute::StackProtect) &&
>>> + !Caller->hasFnAttribute(Attribute::SafeStack) &&
>>> !Caller->hasFnAttribute(Attribute::StackProtectReq) &&
>>> !Caller->hasFnAttribute(Attribute::StackProtectStrong))
>>> Caller->addFnAttr(Attribute::StackProtect);
>>>
>>> Modified: llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt (original)
>>> +++ llvm/trunk/lib/Transforms/Instrumentation/CMakeLists.txt Mon Jun 15 16:07:11 2015
>>> @@ -6,6 +6,7 @@ add_llvm_library(LLVMInstrumentation
>>> MemorySanitizer.cpp
>>> Instrumentation.cpp
>>> InstrProfiling.cpp
>>> + SafeStack.cpp
>>> SanitizerCoverage.cpp
>>> ThreadSanitizer.cpp
>>>
>>>
>>> Modified: llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp?rev=239761&r1=239760&r2=239761&view=diff
>>> ==============================================================================
>>> --- llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp (original)
>>> +++ llvm/trunk/lib/Transforms/Instrumentation/Instrumentation.cpp Mon Jun 15 16:07:11 2015
>>> @@ -30,6 +30,7 @@ void llvm::initializeInstrumentation(Pas
>>> initializeThreadSanitizerPass(Registry);
>>> initializeSanitizerCoverageModulePass(Registry);
>>> initializeDataFlowSanitizerPass(Registry);
>>> + initializeSafeStackPass(Registry);
>>> }
>>>
>>> /// LLVMInitializeInstrumentation - C binding for
>>>
>>> Added: llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp (added)
>>> +++ llvm/trunk/lib/Transforms/Instrumentation/SafeStack.cpp Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,608 @@
>>> +//===-- SafeStack.cpp - Safe Stack Insertion ------------------------------===//
>>> +//
>>> +// The LLVM Compiler Infrastructure
>>> +//
>>> +// This file is distributed under the University of Illinois Open Source
>>> +// License. See LICENSE.TXT for details.
>>> +//
>>> +//===----------------------------------------------------------------------===//
>>> +//
>>> +// This pass splits the stack into the safe stack (kept as-is for LLVM backend)
>>> +// and the unsafe stack (explicitly allocated and managed through the runtime
>>> +// support library).
>>> +//
>>> +// http://clang.llvm.org/docs/SafeStack.html
>>> +//
>>> +//===----------------------------------------------------------------------===//
>>> +
>>> +#include "llvm/Transforms/Instrumentation.h"
>>> +#include "llvm/ADT/Statistic.h"
>>> +#include "llvm/ADT/Triple.h"
>>> +#include "llvm/Analysis/AliasAnalysis.h"
>>> +#include "llvm/Analysis/TargetTransformInfo.h"
>>> +#include "llvm/IR/Constants.h"
>>> +#include "llvm/IR/DataLayout.h"
>>> +#include "llvm/IR/DerivedTypes.h"
>>> +#include "llvm/IR/DIBuilder.h"
>>> +#include "llvm/IR/Function.h"
>>> +#include "llvm/IR/InstIterator.h"
>>> +#include "llvm/IR/Instructions.h"
>>> +#include "llvm/IR/IntrinsicInst.h"
>>> +#include "llvm/IR/Intrinsics.h"
>>> +#include "llvm/IR/IRBuilder.h"
>>> +#include "llvm/IR/Module.h"
>>> +#include "llvm/Pass.h"
>>> +#include "llvm/Support/CommandLine.h"
>>> +#include "llvm/Support/Debug.h"
>>> +#include "llvm/Support/Format.h"
>>> +#include "llvm/Support/MathExtras.h"
>>> +#include "llvm/Support/raw_os_ostream.h"
>>> +#include "llvm/Transforms/Utils/Local.h"
>>> +#include "llvm/Transforms/Utils/ModuleUtils.h"
>>> +
>>> +using namespace llvm;
>>> +
>>> +#define DEBUG_TYPE "safestack"
>>> +
>>> +namespace llvm {
>>> +
>>> +STATISTIC(NumFunctions, "Total number of functions");
>>> +STATISTIC(NumUnsafeStackFunctions, "Number of functions with unsafe stack");
>>> +STATISTIC(NumUnsafeStackRestorePointsFunctions,
>>> + "Number of functions that use setjmp or exceptions");
>>> +
>>> +STATISTIC(NumAllocas, "Total number of allocas");
>>> +STATISTIC(NumUnsafeStaticAllocas, "Number of unsafe static allocas");
>>> +STATISTIC(NumUnsafeDynamicAllocas, "Number of unsafe dynamic allocas");
>>> +STATISTIC(NumUnsafeStackRestorePoints, "Number of setjmps and landingpads");
>>> +
>>> +} // namespace llvm
>>> +
>>> +namespace {
>>> +
>>> +/// Check whether a given alloca instruction (AI) should be put on the safe
>>> +/// stack or not. The function analyzes all uses of AI and checks whether it is
>>> +/// only accessed in a memory safe way (as decided statically).
>>> +bool IsSafeStackAlloca(const AllocaInst *AI) {
>>> + // Go through all uses of this alloca and check whether all accesses to the
>>> + // allocated object are statically known to be memory safe and, hence, the
>>> + // object can be placed on the safe stack.
>>> +
>>> + SmallPtrSet<const Value *, 16> Visited;
>>> + SmallVector<const Instruction *, 8> WorkList;
>>> + WorkList.push_back(AI);
>>> +
>>> + // A DFS search through all uses of the alloca in bitcasts/PHI/GEPs/etc.
>>> + while (!WorkList.empty()) {
>>> + const Instruction *V = WorkList.pop_back_val();
>>> + for (const Use &UI : V->uses()) {
>>> + auto I = cast<const Instruction>(UI.getUser());
>>> + assert(V == UI.get());
>>> +
>>> + switch (I->getOpcode()) {
>>> + case Instruction::Load:
>>> + // Loading from a pointer is safe.
>>> + break;
>>> + case Instruction::VAArg:
>>> + // "va-arg" from a pointer is safe.
>>> + break;
>>> + case Instruction::Store:
>>> + if (V == I->getOperand(0))
>>> + // Stored the pointer - conservatively assume it may be unsafe.
>>> + return false;
>>> + // Storing to the pointee is safe.
>>> + break;
>>> +
>>> + case Instruction::GetElementPtr:
>>> + if (!cast<const GetElementPtrInst>(I)->hasAllConstantIndices())
>>> + // GEP with non-constant indices can lead to memory errors.
>>> + // This also applies to inbounds GEPs, as the inbounds attribute
>>> + // represents an assumption that the address is in bounds, rather than
>>> + // an assertion that it is.
>>> + return false;
>>> +
>>> + // We assume that GEP on static alloca with constant indices is safe,
>>> + // otherwise a compiler would detect it and warn during compilation.
>>> +
>>> + if (!isa<const ConstantInt>(AI->getArraySize()))
>>> + // However, if the array size itself is not constant, the access
>>> + // might still be unsafe at runtime.
>>> + return false;
>>> +
>>> + /* fallthrough */
>>> +
>>> + case Instruction::BitCast:
>>> + case Instruction::IntToPtr:
>>> + case Instruction::PHI:
>>> + case Instruction::PtrToInt:
>>> + case Instruction::Select:
>>> + // The object can be safe or not, depending on how the result of the
>>> + // instruction is used.
>>> + if (Visited.insert(I).second)
>>> + WorkList.push_back(cast<const Instruction>(I));
>>> + break;
>>> +
>>> + case Instruction::Call:
>>> + case Instruction::Invoke: {
>>> + // FIXME: add support for memset and memcpy intrinsics.
>>> + ImmutableCallSite CS(I);
>>> +
>>> + // LLVM 'nocapture' attribute is only set for arguments whose address
>>> + // is not stored, passed around, or used in any other non-trivial way.
>>> + // We assume that passing a pointer to an object as a 'nocapture'
>>> + // argument is safe.
>>> + // FIXME: a more precise solution would require an interprocedural
>>> + // analysis here, which would look at all uses of an argument inside
>>> + // the function being called.
>>> + ImmutableCallSite::arg_iterator B = CS.arg_begin(), E = CS.arg_end();
>>> + for (ImmutableCallSite::arg_iterator A = B; A != E; ++A)
>>> + if (A->get() == V && !CS.doesNotCapture(A - B))
>>> + // The parameter is not marked 'nocapture' - unsafe.
>>> + return false;
>>> + continue;
>>> + }
>>> +
>>> + default:
>>> + // The object is unsafe if it is used in any other way.
>>> + return false;
>>> + }
>>> + }
>>> + }
>>> +
>>> + // All uses of the alloca are safe, we can place it on the safe stack.
>>> + return true;
>>> +}
>>> +
>>> +/// The SafeStack pass splits the stack of each function into the
>>> +/// safe stack, which is only accessed through memory safe dereferences
>>> +/// (as determined statically), and the unsafe stack, which contains all
>>> +/// local variables that are accessed in unsafe ways.
>>> +class SafeStack : public FunctionPass {
>>> + const DataLayout *DL;
>>> +
>>> + Type *StackPtrTy;
>>> + Type *IntPtrTy;
>>> + Type *Int32Ty;
>>> + Type *Int8Ty;
>>> +
>>> + Constant *UnsafeStackPtr;
>>> +
>>> + /// Unsafe stack alignment. Each stack frame must ensure that the stack is
>>> + /// aligned to this value. We need to re-align the unsafe stack if the
>>> + /// alignment of any object on the stack exceeds this value.
>>> + ///
>>> + /// 16 seems like a reasonable upper bound on the alignment of objects that we
>>> + /// might expect to appear on the stack on most common targets.
>>> + enum { StackAlignment = 16 };
>>> +
>>> + /// \brief Build a constant representing a pointer to the unsafe stack
>>> + /// pointer.
>>> + Constant *getOrCreateUnsafeStackPtr(Module &M);
>>> +
>>> + /// \brief Find all static allocas, dynamic allocas, return instructions and
>>> + /// stack restore points (exception unwind blocks and setjmp calls) in the
>>> + /// given function and append them to the respective vectors.
>>> + void findInsts(Function &F, SmallVectorImpl<AllocaInst *> &StaticAllocas,
>>> + SmallVectorImpl<AllocaInst *> &DynamicAllocas,
>>> + SmallVectorImpl<ReturnInst *> &Returns,
>>> + SmallVectorImpl<Instruction *> &StackRestorePoints);
>>> +
>>> + /// \brief Allocate space for all static allocas in \p StaticAllocas,
>>> + /// replace allocas with pointers into the unsafe stack and generate code to
>>> + /// restore the stack pointer before all return instructions in \p Returns.
>>> + ///
>>> + /// \returns A pointer to the top of the unsafe stack after all unsafe static
>>> + /// allocas are allocated.
>>> + Value *moveStaticAllocasToUnsafeStack(Function &F,
>>> + ArrayRef<AllocaInst *> StaticAllocas,
>>> + ArrayRef<ReturnInst *> Returns);
>>> +
>>> + /// \brief Generate code to restore the stack after all stack restore points
>>> + /// in \p StackRestorePoints.
>>> + ///
>>> + /// \returns A local variable in which to maintain the dynamic top of the
>>> + /// unsafe stack if needed.
>>> + AllocaInst *
>>> + createStackRestorePoints(Function &F,
>>> + ArrayRef<Instruction *> StackRestorePoints,
>>> + Value *StaticTop, bool NeedDynamicTop);
>>> +
>>> + /// \brief Replace all allocas in \p DynamicAllocas with code to allocate
>>> + /// space dynamically on the unsafe stack and store the dynamic unsafe stack
>>> + /// top to \p DynamicTop if non-null.
>>> + void moveDynamicAllocasToUnsafeStack(Function &F, Value *UnsafeStackPtr,
>>> + AllocaInst *DynamicTop,
>>> + ArrayRef<AllocaInst *> DynamicAllocas);
>>> +
>>> +public:
>>> + static char ID; // Pass identification, replacement for typeid.
>>> + SafeStack() : FunctionPass(ID), DL(nullptr) {
>>> + initializeSafeStackPass(*PassRegistry::getPassRegistry());
>>> + }
>>> +
>>> + virtual void getAnalysisUsage(AnalysisUsage &AU) const {
>>> + AU.addRequired<AliasAnalysis>();
>>> + }
>>> +
>>> + virtual bool doInitialization(Module &M) {
>>> + DL = &M.getDataLayout();
>>> +
>>> + StackPtrTy = Type::getInt8PtrTy(M.getContext());
>>> + IntPtrTy = DL->getIntPtrType(M.getContext());
>>> + Int32Ty = Type::getInt32Ty(M.getContext());
>>> + Int8Ty = Type::getInt8Ty(M.getContext());
>>> +
>>> + UnsafeStackPtr = getOrCreateUnsafeStackPtr(M);
>>> +
>>> + return false;
>>> + }
>>> +
>>> + bool runOnFunction(Function &F);
>>> +
>>> +}; // class SafeStack
>>> +
>>> +Constant *SafeStack::getOrCreateUnsafeStackPtr(Module &M) {
>>> + // The unsafe stack pointer is stored in a global variable with a magic name.
>>> + const char *kUnsafeStackPtrVar = "__safestack_unsafe_stack_ptr";
>>> +
>>> + auto UnsafeStackPtr =
>>> + dyn_cast_or_null<GlobalVariable>(M.getNamedValue(kUnsafeStackPtrVar));
>>> +
>>> + if (!UnsafeStackPtr) {
>>> + // The global variable is not defined yet, define it ourselves.
>>> + // We use the initial-exec TLS model because we do not support the variable
>>> + // living anywhere other than in the main executable.
>>> + UnsafeStackPtr = new GlobalVariable(
>>> + /*Module=*/M, /*Type=*/StackPtrTy,
>>> + /*isConstant=*/false, /*Linkage=*/GlobalValue::ExternalLinkage,
>>> + /*Initializer=*/0, /*Name=*/kUnsafeStackPtrVar,
>>> + /*InsertBefore=*/nullptr,
>>> + /*ThreadLocalMode=*/GlobalValue::InitialExecTLSModel);
>>> + } else {
>>> + // The variable exists, check its type and attributes.
>>> + if (UnsafeStackPtr->getValueType() != StackPtrTy) {
>>> + report_fatal_error(Twine(kUnsafeStackPtrVar) + " must have void* type");
>>> + }
>>> +
>>> + if (!UnsafeStackPtr->isThreadLocal()) {
>>> + report_fatal_error(Twine(kUnsafeStackPtrVar) + " must be thread-local");
>>> + }
>>> + }
>>> +
>>> + return UnsafeStackPtr;
>>> +}
>>> +
>>> +void SafeStack::findInsts(Function &F,
>>> + SmallVectorImpl<AllocaInst *> &StaticAllocas,
>>> + SmallVectorImpl<AllocaInst *> &DynamicAllocas,
>>> + SmallVectorImpl<ReturnInst *> &Returns,
>>> + SmallVectorImpl<Instruction *> &StackRestorePoints) {
>>> + for (Instruction &I : inst_range(&F)) {
>>> + if (auto AI = dyn_cast<AllocaInst>(&I)) {
>>> + ++NumAllocas;
>>> +
>>> + if (IsSafeStackAlloca(AI))
>>> + continue;
>>> +
>>> + if (AI->isStaticAlloca()) {
>>> + ++NumUnsafeStaticAllocas;
>>> + StaticAllocas.push_back(AI);
>>> + } else {
>>> + ++NumUnsafeDynamicAllocas;
>>> + DynamicAllocas.push_back(AI);
>>> + }
>>> + } else if (auto RI = dyn_cast<ReturnInst>(&I)) {
>>> + Returns.push_back(RI);
>>> + } else if (auto CI = dyn_cast<CallInst>(&I)) {
>>> + // setjmps require stack restore.
>>> + if (CI->getCalledFunction() && CI->canReturnTwice())
>>> + StackRestorePoints.push_back(CI);
>>> + } else if (auto LP = dyn_cast<LandingPadInst>(&I)) {
>>> + // Exception landing pads require stack restore.
>>> + StackRestorePoints.push_back(LP);
>>> + } else if (auto II = dyn_cast<IntrinsicInst>(&I)) {
>>> + if (II->getIntrinsicID() == Intrinsic::gcroot)
>>> + llvm::report_fatal_error(
>>> + "gcroot intrinsic not compatible with safestack attribute");
>>> + }
>>> + }
>>> +}
>>> +
>>> +AllocaInst *
>>> +SafeStack::createStackRestorePoints(Function &F,
>>> + ArrayRef<Instruction *> StackRestorePoints,
>>> + Value *StaticTop, bool NeedDynamicTop) {
>>> + if (StackRestorePoints.empty())
>>> + return nullptr;
>>> +
>>> + IRBuilder<> IRB(StaticTop
>>> + ? cast<Instruction>(StaticTop)->getNextNode()
>>> + : (Instruction *)F.getEntryBlock().getFirstInsertionPt());
>>> +
>>> + // We need the current value of the shadow stack pointer to restore
>>> + // after longjmp or exception catching.
>>> +
>>> + // FIXME: On some platforms this could be handled by the longjmp/exception
>>> + // runtime itself.
>>> +
>>> + AllocaInst *DynamicTop = nullptr;
>>> + if (NeedDynamicTop)
>>> + // If we also have dynamic alloca's, the stack pointer value changes
>>> + // throughout the function. For now we store it in an alloca.
>>> + DynamicTop = IRB.CreateAlloca(StackPtrTy, /*ArraySize=*/nullptr,
>>> + "unsafe_stack_dynamic_ptr");
>>> +
>>> + if (!StaticTop)
>>> + // We need the original unsafe stack pointer value, even if there are
>>> + // no unsafe static allocas.
>>> + StaticTop = IRB.CreateLoad(UnsafeStackPtr, false, "unsafe_stack_ptr");
>>> +
>>> + if (NeedDynamicTop)
>>> + IRB.CreateStore(StaticTop, DynamicTop);
>>> +
>>> + // Restore current stack pointer after longjmp/exception catch.
>>> + for (Instruction *I : StackRestorePoints) {
>>> + ++NumUnsafeStackRestorePoints;
>>> +
>>> + IRB.SetInsertPoint(cast<Instruction>(I->getNextNode()));
>>> + Value *CurrentTop = DynamicTop ? IRB.CreateLoad(DynamicTop) : StaticTop;
>>> + IRB.CreateStore(CurrentTop, UnsafeStackPtr);
>>> + }
>>> +
>>> + return DynamicTop;
>>> +}
>>> +
>>> +Value *
>>> +SafeStack::moveStaticAllocasToUnsafeStack(Function &F,
>>> + ArrayRef<AllocaInst *> StaticAllocas,
>>> + ArrayRef<ReturnInst *> Returns) {
>>> + if (StaticAllocas.empty())
>>> + return nullptr;
>>> +
>>> + IRBuilder<> IRB(F.getEntryBlock().getFirstInsertionPt());
>>> + DIBuilder DIB(*F.getParent());
>>> +
>>> + // We explicitly compute and set the unsafe stack layout for all unsafe
>>> + // static alloca instructions. We save the unsafe "base pointer" in the
>>> + // prologue into a local variable and restore it in the epilogue.
>>> +
>>> + // Load the current stack pointer (we'll also use it as a base pointer).
>>> + // FIXME: use a dedicated register for it ?
>>> + Instruction *BasePointer =
>>> + IRB.CreateLoad(UnsafeStackPtr, false, "unsafe_stack_ptr");
>>> + assert(BasePointer->getType() == StackPtrTy);
>>> +
>>> + for (ReturnInst *RI : Returns) {
>>> + IRB.SetInsertPoint(RI);
>>> + IRB.CreateStore(BasePointer, UnsafeStackPtr);
>>> + }
>>> +
>>> + // Compute maximum alignment among static objects on the unsafe stack.
>>> + unsigned MaxAlignment = 0;
>>> + for (AllocaInst *AI : StaticAllocas) {
>>> + Type *Ty = AI->getAllocatedType();
>>> + unsigned Align =
>>> + std::max((unsigned)DL->getPrefTypeAlignment(Ty), AI->getAlignment());
>>> + if (Align > MaxAlignment)
>>> + MaxAlignment = Align;
>>> + }
>>> +
>>> + if (MaxAlignment > StackAlignment) {
>>> + // Re-align the base pointer according to the max requested alignment.
>>> + assert(isPowerOf2_32(MaxAlignment));
>>> + IRB.SetInsertPoint(cast<Instruction>(BasePointer->getNextNode()));
>>> + BasePointer = cast<Instruction>(IRB.CreateIntToPtr(
>>> + IRB.CreateAnd(IRB.CreatePtrToInt(BasePointer, IntPtrTy),
>>> + ConstantInt::get(IntPtrTy, ~uint64_t(MaxAlignment - 1))),
>>> + StackPtrTy));
>>> + }
>>> +
>>> + // Allocate space for every unsafe static AllocaInst on the unsafe stack.
>>> + int64_t StaticOffset = 0; // Current stack top.
>>> + for (AllocaInst *AI : StaticAllocas) {
>>> + IRB.SetInsertPoint(AI);
>>> +
>>> + auto CArraySize = cast<ConstantInt>(AI->getArraySize());
>>> + Type *Ty = AI->getAllocatedType();
>>> +
>>> + uint64_t Size = DL->getTypeAllocSize(Ty) * CArraySize->getZExtValue();
>>> + if (Size == 0)
>>> + Size = 1; // Don't create zero-sized stack objects.
>>> +
>>> + // Ensure the object is properly aligned.
>>> + unsigned Align =
>>> + std::max((unsigned)DL->getPrefTypeAlignment(Ty), AI->getAlignment());
>>> +
>>> + // Add alignment.
>>> + // NOTE: we ensure that BasePointer itself is aligned to >= Align.
>>> + StaticOffset += Size;
>>> + StaticOffset = RoundUpToAlignment(StaticOffset, Align);
>>> +
>>> + Value *Off = IRB.CreateGEP(BasePointer, // BasePointer is i8*
>>> + ConstantInt::get(Int32Ty, -StaticOffset));
>>> + Value *NewAI = IRB.CreateBitCast(Off, AI->getType(), AI->getName());
>>> + if (AI->hasName() && isa<Instruction>(NewAI))
>>> + cast<Instruction>(NewAI)->takeName(AI);
>>> +
>>> + // Replace alloc with the new location.
>>> + replaceDbgDeclareForAlloca(AI, NewAI, DIB, /*Deref=*/true);
>>> + AI->replaceAllUsesWith(NewAI);
>>> + AI->eraseFromParent();
>>> + }
>>> +
>>> + // Re-align BasePointer so that our callees would see it aligned as
>>> + // expected.
>>> + // FIXME: no need to update BasePointer in leaf functions.
>>> + StaticOffset = RoundUpToAlignment(StaticOffset, StackAlignment);
>>> +
>>> + // Update shadow stack pointer in the function epilogue.
>>> + IRB.SetInsertPoint(cast<Instruction>(BasePointer->getNextNode()));
>>> +
>>> + Value *StaticTop =
>>> + IRB.CreateGEP(BasePointer, ConstantInt::get(Int32Ty, -StaticOffset),
>>> + "unsafe_stack_static_top");
>>> + IRB.CreateStore(StaticTop, UnsafeStackPtr);
>>> + return StaticTop;
>>> +}
>>> +
>>> +void SafeStack::moveDynamicAllocasToUnsafeStack(
>>> + Function &F, Value *UnsafeStackPtr, AllocaInst *DynamicTop,
>>> + ArrayRef<AllocaInst *> DynamicAllocas) {
>>> + DIBuilder DIB(*F.getParent());
>>> +
>>> + for (AllocaInst *AI : DynamicAllocas) {
>>> + IRBuilder<> IRB(AI);
>>> +
>>> + // Compute the new SP value (after AI).
>>> + Value *ArraySize = AI->getArraySize();
>>> + if (ArraySize->getType() != IntPtrTy)
>>> + ArraySize = IRB.CreateIntCast(ArraySize, IntPtrTy, false);
>>> +
>>> + Type *Ty = AI->getAllocatedType();
>>> + uint64_t TySize = DL->getTypeAllocSize(Ty);
>>> + Value *Size = IRB.CreateMul(ArraySize, ConstantInt::get(IntPtrTy, TySize));
>>> +
>>> + Value *SP = IRB.CreatePtrToInt(IRB.CreateLoad(UnsafeStackPtr), IntPtrTy);
>>> + SP = IRB.CreateSub(SP, Size);
>>> +
>>> + // Align the SP value to satisfy the AllocaInst, type and stack alignments.
>>> + unsigned Align = std::max(
>>> + std::max((unsigned)DL->getPrefTypeAlignment(Ty), AI->getAlignment()),
>>> + (unsigned)StackAlignment);
>>> +
>>> + assert(isPowerOf2_32(Align));
>>> + Value *NewTop = IRB.CreateIntToPtr(
>>> + IRB.CreateAnd(SP, ConstantInt::get(IntPtrTy, ~uint64_t(Align - 1))),
>>> + StackPtrTy);
>>> +
>>> + // Save the stack pointer.
>>> + IRB.CreateStore(NewTop, UnsafeStackPtr);
>>> + if (DynamicTop)
>>> + IRB.CreateStore(NewTop, DynamicTop);
>>> +
>>> + Value *NewAI = IRB.CreateIntToPtr(SP, AI->getType());
>>> + if (AI->hasName() && isa<Instruction>(NewAI))
>>> + NewAI->takeName(AI);
>>> +
>>> + replaceDbgDeclareForAlloca(AI, NewAI, DIB, /*Deref=*/true);
>>> + AI->replaceAllUsesWith(NewAI);
>>> + AI->eraseFromParent();
>>> + }
>>> +
>>> + if (!DynamicAllocas.empty()) {
>>> + // Now go through the instructions again, replacing stacksave/stackrestore.
>>> + for (inst_iterator It = inst_begin(&F), Ie = inst_end(&F); It != Ie;) {
>>> + Instruction *I = &*(It++);
>>> + auto II = dyn_cast<IntrinsicInst>(I);
>>> + if (!II)
>>> + continue;
>>> +
>>> + if (II->getIntrinsicID() == Intrinsic::stacksave) {
>>> + IRBuilder<> IRB(II);
>>> + Instruction *LI = IRB.CreateLoad(UnsafeStackPtr);
>>> + LI->takeName(II);
>>> + II->replaceAllUsesWith(LI);
>>> + II->eraseFromParent();
>>> + } else if (II->getIntrinsicID() == Intrinsic::stackrestore) {
>>> + IRBuilder<> IRB(II);
>>> + Instruction *SI = IRB.CreateStore(II->getArgOperand(0), UnsafeStackPtr);
>>> + SI->takeName(II);
>>> + assert(II->use_empty());
>>> + II->eraseFromParent();
>>> + }
>>> + }
>>> + }
>>> +}
>>> +
>>> +bool SafeStack::runOnFunction(Function &F) {
>>> + auto AA = &getAnalysis<AliasAnalysis>();
>>> +
>>> + DEBUG(dbgs() << "[SafeStack] Function: " << F.getName() << "\n");
>>> +
>>> + if (!F.hasFnAttribute(Attribute::SafeStack)) {
>>> + DEBUG(dbgs() << "[SafeStack] safestack is not requested"
>>> + " for this function\n");
>>> + return false;
>>> + }
>>> +
>>> + if (F.isDeclaration()) {
>>> + DEBUG(dbgs() << "[SafeStack] function definition"
>>> + " is not available\n");
>>> + return false;
>>> + }
>>> +
>>> + {
>>> + // Make sure the regular stack protector won't run on this function
>>> + // (safestack attribute takes precedence).
>>> + AttrBuilder B;
>>> + B.addAttribute(Attribute::StackProtect)
>>> + .addAttribute(Attribute::StackProtectReq)
>>> + .addAttribute(Attribute::StackProtectStrong);
>>> + F.removeAttributes(
>>> + AttributeSet::FunctionIndex,
>>> + AttributeSet::get(F.getContext(), AttributeSet::FunctionIndex, B));
>>> + }
>>> +
>>> + if (AA->onlyReadsMemory(&F)) {
>>> + // XXX: we don't protect against information leak attacks for now.
>>> + DEBUG(dbgs() << "[SafeStack] function only reads memory\n");
>>> + return false;
>>> + }
>>> +
>>> + ++NumFunctions;
>>> +
>>> + SmallVector<AllocaInst *, 16> StaticAllocas;
>>> + SmallVector<AllocaInst *, 4> DynamicAllocas;
>>> + SmallVector<ReturnInst *, 4> Returns;
>>> +
>>> + // Collect all points where stack gets unwound and needs to be restored
>>> + // This is only necessary because the runtime (setjmp and unwind code) is
>>> + // not aware of the unsafe stack and won't unwind/restore it prorerly.
>>> + // To work around this problem without changing the runtime, we insert
>>> + // instrumentation to restore the unsafe stack pointer when necessary.
>>> + SmallVector<Instruction *, 4> StackRestorePoints;
>>> +
>>> + // Find all static and dynamic alloca instructions that must be moved to the
>>> + // unsafe stack, all return instructions and stack restore points.
>>> + findInsts(F, StaticAllocas, DynamicAllocas, Returns, StackRestorePoints);
>>> +
>>> + if (StaticAllocas.empty() && DynamicAllocas.empty() &&
>>> + StackRestorePoints.empty())
>>> + return false; // Nothing to do in this function.
>>> +
>>> + if (!StaticAllocas.empty() || !DynamicAllocas.empty())
>>> + ++NumUnsafeStackFunctions; // This function has the unsafe stack.
>>> +
>>> + if (!StackRestorePoints.empty())
>>> + ++NumUnsafeStackRestorePointsFunctions;
>>> +
>>> + // The top of the unsafe stack after all unsafe static allocas are allocated.
>>> + Value *StaticTop = moveStaticAllocasToUnsafeStack(F, StaticAllocas, Returns);
>>> +
>>> + // Safe stack object that stores the current unsafe stack top. It is updated
>>> + // as unsafe dynamic (non-constant-sized) allocas are allocated and freed.
>>> + // This is only needed if we need to restore stack pointer after longjmp
>>> + // or exceptions, and we have dynamic allocations.
>>> + // FIXME: a better alternative might be to store the unsafe stack pointer
>>> + // before setjmp / invoke instructions.
>>> + AllocaInst *DynamicTop = createStackRestorePoints(
>>> + F, StackRestorePoints, StaticTop, !DynamicAllocas.empty());
>>> +
>>> + // Handle dynamic allocas.
>>> + moveDynamicAllocasToUnsafeStack(F, UnsafeStackPtr, DynamicTop,
>>> + DynamicAllocas);
>>> +
>>> + DEBUG(dbgs() << "[SafeStack] safestack applied\n");
>>> + return true;
>>> +}
>>> +
>>> +} // end anonymous namespace
>>> +
>>> +char SafeStack::ID = 0;
>>> +INITIALIZE_PASS_BEGIN(SafeStack, "safe-stack",
>>> + "Safe Stack instrumentation pass", false, false)
>>> +INITIALIZE_PASS_DEPENDENCY(TargetTransformInfoWrapperPass)
>>> +INITIALIZE_PASS_END(SafeStack, "safe-stack", "Safe Stack instrumentation pass",
>>> + false, false)
>>> +
>>> +FunctionPass *llvm::createSafeStackPass() { return new SafeStack(); }
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/addr-taken.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/addr-taken.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/addr-taken.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/addr-taken.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,22 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Address-of local taken (j = &a)
>>> +; Requires protector.
>>> +
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %retval = alloca i32, align 4
>>> + %a = alloca i32, align 4
>>> + %j = alloca i32*, align 8
>>> + store i32 0, i32* %retval
>>> + %0 = load i32, i32* %a, align 4
>>> + %add = add nsw i32 %0, 1
>>> + store i32 %add, i32* %a, align 4
>>> + store i32* %a, i32** %j, align 8
>>> + ret void
>>> +}
>>> +
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/array-aligned.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/array-aligned.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/array-aligned.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/array-aligned.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,39 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; array of [16 x i8]
>>> +
>>> +define void @foo(i8* %a) nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: %[[USP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
>>> +
>>> + ; CHECK: %[[USST:.*]] = getelementptr i8, i8* %[[USP]], i32 -16
>>> +
>>> + ; CHECK: store i8* %[[USST]], i8** @__safestack_unsafe_stack_ptr
>>> +
>>> + ; CHECK: %[[AADDR:.*]] = alloca i8*, align 8
>>> + %a.addr = alloca i8*, align 8
>>> +
>>> + ; CHECK: %[[BUFPTR:.*]] = getelementptr i8, i8* %[[USP]], i32 -16
>>> + ; CHECK: %[[BUFPTR2:.*]] = bitcast i8* %[[BUFPTR]] to [16 x i8]*
>>> + %buf = alloca [16 x i8], align 16
>>> +
>>> + ; CHECK: store i8* {{.*}}, i8** %[[AADDR]], align 8
>>> + store i8* %a, i8** %a.addr, align 8
>>> +
>>> + ; CHECK: %[[GEP:.*]] = getelementptr inbounds [16 x i8], [16 x i8]* %[[BUFPTR2]], i32 0, i32 0
>>> + %gep = getelementptr inbounds [16 x i8], [16 x i8]* %buf, i32 0, i32 0
>>> +
>>> + ; CHECK: %[[A2:.*]] = load i8*, i8** %[[AADDR]], align 8
>>> + %a2 = load i8*, i8** %a.addr, align 8
>>> +
>>> + ; CHECK: call i8* @strcpy(i8* %[[GEP]], i8* %[[A2]])
>>> + %call = call i8* @strcpy(i8* %gep, i8* %a2)
>>> +
>>> + ; CHECK: store i8* %[[USP]], i8** @__safestack_unsafe_stack_ptr
>>> + ret void
>>> +}
>>> +
>>> +declare i8* @strcpy(i8*, i8*)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/array.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/array.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/array.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/array.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,38 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +; array [4 x i8]
>>> +; Requires protector.
>>> +
>>> +define void @foo(i8* %a) nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: %[[USP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
>>> +
>>> + ; CHECK: %[[USST:.*]] = getelementptr i8, i8* %[[USP]], i32 -16
>>> +
>>> + ; CHECK: store i8* %[[USST]], i8** @__safestack_unsafe_stack_ptr
>>> +
>>> + ; CHECK: %[[AADDR:.*]] = alloca i8*, align 8
>>> + %a.addr = alloca i8*, align 8
>>> +
>>> + ; CHECK: %[[BUFPTR:.*]] = getelementptr i8, i8* %[[USP]], i32 -4
>>> + ; CHECK: %[[BUFPTR2:.*]] = bitcast i8* %[[BUFPTR]] to [4 x i8]*
>>> + %buf = alloca [4 x i8], align 1
>>> +
>>> + ; CHECK: store i8* {{.*}}, i8** %[[AADDR]], align 8
>>> + store i8* %a, i8** %a.addr, align 8
>>> +
>>> + ; CHECK: %[[GEP:.*]] = getelementptr inbounds [4 x i8], [4 x i8]* %[[BUFPTR2]], i32 0, i32 0
>>> + %gep = getelementptr inbounds [4 x i8], [4 x i8]* %buf, i32 0, i32 0
>>> +
>>> + ; CHECK: %[[A2:.*]] = load i8*, i8** %[[AADDR]], align 8
>>> + %a2 = load i8*, i8** %a.addr, align 8
>>> +
>>> + ; CHECK: call i8* @strcpy(i8* %[[GEP]], i8* %[[A2]])
>>> + %call = call i8* @strcpy(i8* %gep, i8* %a2)
>>> +
>>> + ; CHECK: store i8* %[[USP]], i8** @__safestack_unsafe_stack_ptr
>>> + ret void
>>> +}
>>> +
>>> +declare i8* @strcpy(i8*, i8*)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/call.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/call.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/call.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/call.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,20 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; no arrays / no nested arrays
>>> +; Requires no protector.
>>> +
>>> +; CHECK-LABEL: @foo(
>>> +define void @foo(i8* %a) nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK-NOT: __safestack_unsafe_stack_ptr
>>> + %a.addr = alloca i8*, align 8
>>> + store i8* %a, i8** %a.addr, align 8
>>> + %0 = load i8*, i8** %a.addr, align 8
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i8* %0)
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/cast.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/cast.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/cast.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/cast.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,17 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; PtrToInt/IntToPtr Cast
>>> +; Requires no protector.
>>> +
>>> +; CHECK-LABEL: @foo(
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK-NOT: __safestack_unsafe_stack_ptr
>>> + %a = alloca i32, align 4
>>> + %0 = ptrtoint i32* %a to i64
>>> + %1 = inttoptr i64 %0 to i32*
>>> + ret void
>>> +}
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/constant-gep-call.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/constant-gep-call.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/constant-gep-call.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/constant-gep-call.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,26 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.nest = type { %struct.pair, %struct.pair }
>>> +%struct.pair = type { i32, i32 }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Nested structure, no arrays, no address-of expressions.
>>> +; Verify that the resulting gep-of-gep does not incorrectly trigger
>>> +; a safe stack protector.
>>> +; safestack attribute
>>> +; Requires no protector.
>>> +; CHECK-LABEL: @foo(
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK-NOT: __safestack_unsafe_stack_ptr
>>> + %c = alloca %struct.nest, align 4
>>> + %b = getelementptr inbounds %struct.nest, %struct.nest* %c, i32 0, i32 1
>>> + %_a = getelementptr inbounds %struct.pair, %struct.pair* %b, i32 0, i32 0
>>> + %0 = load i32, i32* %_a, align 4
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32 %0)
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/constant-gep.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/constant-gep.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/constant-gep.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/constant-gep.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,20 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%class.A = type { [2 x i8] }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; [2 x i8] in a class
>>> +; safestack attribute
>>> +; Requires no protector.
>>> +; CHECK-LABEL: @foo(
>>> +define signext i8 @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK-NOT: __safestack_unsafe_stack_ptr
>>> + %a = alloca %class.A, align 1
>>> + %array = getelementptr inbounds %class.A, %class.A* %a, i32 0, i32 0
>>> + %arrayidx = getelementptr inbounds [2 x i8], [2 x i8]* %array, i32 0, i64 0
>>> + %0 = load i8, i8* %arrayidx, align 1
>>> + ret i8 %0
>>> +}
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/constant-geps.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/constant-geps.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/constant-geps.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/constant-geps.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,28 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.deep = type { %union.anon }
>>> +%union.anon = type { %struct.anon }
>>> +%struct.anon = type { %struct.anon.0 }
>>> +%struct.anon.0 = type { %union.anon.1 }
>>> +%union.anon.1 = type { [2 x i8] }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; [2 x i8] nested in several layers of structs and unions
>>> +; safestack attribute
>>> +; Requires no protector.
>>> +; CHECK-LABEL: @foo(
>>> +define signext i8 @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK-NOT: __safestack_unsafe_stack_ptr
>>> + %x = alloca %struct.deep, align 1
>>> + %b = getelementptr inbounds %struct.deep, %struct.deep* %x, i32 0, i32 0
>>> + %c = bitcast %union.anon* %b to %struct.anon*
>>> + %d = getelementptr inbounds %struct.anon, %struct.anon* %c, i32 0, i32 0
>>> + %e = getelementptr inbounds %struct.anon.0, %struct.anon.0* %d, i32 0, i32 0
>>> + %array = bitcast %union.anon.1* %e to [2 x i8]*
>>> + %arrayidx = getelementptr inbounds [2 x i8], [2 x i8]* %array, i32 0, i64 0
>>> + %0 = load i8, i8* %arrayidx, align 1
>>> + ret i8 %0
>>> +}
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/dynamic-alloca.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/dynamic-alloca.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/dynamic-alloca.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/dynamic-alloca.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,21 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Variable sized alloca
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo(i32 %n) nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %n.addr = alloca i32, align 4
>>> + %a = alloca i32*, align 8
>>> + store i32 %n, i32* %n.addr, align 4
>>> + %0 = load i32, i32* %n.addr, align 4
>>> + %conv = sext i32 %0 to i64
>>> + %1 = alloca i8, i64 %conv
>>> + %2 = bitcast i8* %1 to i32*
>>> + store i32* %2, i32** %a, align 8
>>> + ret void
>>> +}
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-addr-pointer.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-addr-pointer.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-addr-pointer.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-addr-pointer.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,23 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a pointer
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %a = alloca i32*, align 8
>>> + %b = alloca i32**, align 8
>>> + %call = call i32* @getp()
>>> + store i32* %call, i32** %a, align 8
>>> + store i32** %a, i32*** %b, align 8
>>> + %0 = load i32**, i32*** %b, align 8
>>> + call void @funcall2(i32** %0)
>>> + ret void
>>> +}
>>> +
>>> +declare void @funcall2(i32**)
>>> +declare i32* @getp()
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,23 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a local cast to a ptr of a different type
>>> +; (e.g., int a; ... ; float *b = &a;)
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %a = alloca i32, align 4
>>> + %b = alloca float*, align 8
>>> + store i32 0, i32* %a, align 4
>>> + %0 = bitcast i32* %a to float*
>>> + store float* %0, float** %b, align 8
>>> + %1 = load float*, float** %b, align 8
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), float* %1)
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store2.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store2.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store2.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-bitcast-store2.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,20 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a local cast to a ptr of a different type (optimized)
>>> +; (e.g., int a; ... ; float *b = &a;)
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %a = alloca i32, align 4
>>> + store i32 0, i32* %a, align 4
>>> + %0 = bitcast i32* %a to float*
>>> + call void @funfloat(float* %0) nounwind
>>> + ret void
>>> +}
>>> +
>>> +declare void @funfloat(float*)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-call.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-call.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-call.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-call.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,16 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Passing addr-of to function call
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %b = alloca i32, align 4
>>> + call void @funcall(i32* %b) nounwind
>>> + ret void
>>> +}
>>> +
>>> +declare void @funcall(i32*)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-casted-pointer.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-casted-pointer.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-casted-pointer.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-casted-pointer.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,24 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a casted pointer
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %a = alloca i32*, align 8
>>> + %b = alloca float**, align 8
>>> + %call = call i32* @getp()
>>> + store i32* %call, i32** %a, align 8
>>> + %0 = bitcast i32** %a to float**
>>> + store float** %0, float*** %b, align 8
>>> + %1 = load float**, float*** %b, align 8
>>> + call void @funfloat2(float** %1)
>>> + ret void
>>> +}
>>> +
>>> +declare void @funfloat2(float**)
>>> +declare i32* @getp()
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-gep-call.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-gep-call.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-gep-call.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-gep-call.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,20 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.pair = type { i32, i32 }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of struct element, GEP followed by callinst.
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %c = alloca %struct.pair, align 4
>>> + %y = getelementptr inbounds %struct.pair, %struct.pair* %c, i64 0, i32 1
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i32* %y) nounwind
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-gep-invoke.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-gep-invoke.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-gep-invoke.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-gep-invoke.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,34 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.pair = type { i32, i32 }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a struct element passed into an invoke instruction.
>>> +; (GEP followed by an invoke)
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define i32 @foo() uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %c = alloca %struct.pair, align 4
>>> + %exn.slot = alloca i8*
>>> + %ehselector.slot = alloca i32
>>> + %a = getelementptr inbounds %struct.pair, %struct.pair* %c, i32 0, i32 0
>>> + store i32 0, i32* %a, align 4
>>> + %a1 = getelementptr inbounds %struct.pair, %struct.pair* %c, i32 0, i32 0
>>> + invoke void @_Z3exceptPi(i32* %a1)
>>> + to label %invoke.cont unwind label %lpad
>>> +
>>> +invoke.cont:
>>> + ret i32 0
>>> +
>>> +lpad:
>>> + %0 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
>>> + catch i8* null
>>> + ret i32 0
>>> +}
>>> +
>>> +declare void @_Z3exceptPi(i32*)
>>> +declare i32 @__gxx_personality_v0(...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-gep-negative.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-gep-negative.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-gep-negative.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-gep-negative.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,18 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a local, optimized into a GEP (e.g., &a - 12)
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %a = alloca i32, align 4
>>> + %add.ptr5 = getelementptr inbounds i32, i32* %a, i64 -12
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), i32* %add.ptr5) nounwind
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-gep-ptrtoint.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-gep-ptrtoint.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-gep-ptrtoint.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-gep-ptrtoint.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,22 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.pair = type { i32, i32 }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of struct element, GEP followed by ptrtoint.
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %c = alloca %struct.pair, align 4
>>> + %b = alloca i32*, align 8
>>> + %y = getelementptr inbounds %struct.pair, %struct.pair* %c, i32 0, i32 1
>>> + %0 = ptrtoint i32* %y to i64
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i64 %0)
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-gep-store.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-gep-store.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-gep-store.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-gep-store.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,23 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.pair = type { i32, i32 }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of struct element. (GEP followed by store).
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %c = alloca %struct.pair, align 4
>>> + %b = alloca i32*, align 8
>>> + %y = getelementptr inbounds %struct.pair, %struct.pair* %c, i32 0, i32 1
>>> + store i32* %y, i32** %b, align 8
>>> + %0 = load i32*, i32** %b, align 8
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i32* %0)
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-phi-call.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-phi-call.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-phi-call.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-phi-call.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,36 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of in phi instruction
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %x = alloca double, align 8
>>> + %call = call double @testi_aux() nounwind
>>> + store double %call, double* %x, align 8
>>> + %cmp = fcmp ogt double %call, 3.140000e+00
>>> + br i1 %cmp, label %if.then, label %if.else
>>> +
>>> +if.then: ; preds = %entry
>>> + %call1 = call double @testi_aux() nounwind
>>> + store double %call1, double* %x, align 8
>>> + br label %if.end4
>>> +
>>> +if.else: ; preds = %entry
>>> + %cmp2 = fcmp ogt double %call, 1.000000e+00
>>> + br i1 %cmp2, label %if.then3, label %if.end4
>>> +
>>> +if.then3: ; preds = %if.else
>>> + br label %if.end4
>>> +
>>> +if.end4: ; preds = %if.else, %if.then3, %if.then
>>> + %y.0 = phi double* [ null, %if.then ], [ %x, %if.then3 ], [ null, %if.else ]
>>> + %call5 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), double* %y.0) nounwind
>>> + ret void
>>> +}
>>> +
>>> +declare double @testi_aux()
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-select-call.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-select-call.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-select-call.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-select-call.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,22 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of in select instruction
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %x = alloca double, align 8
>>> + %call = call double @testi_aux() nounwind
>>> + store double %call, double* %x, align 8
>>> + %cmp2 = fcmp ogt double %call, 0.000000e+00
>>> + %y.1 = select i1 %cmp2, double* %x, double* null
>>> + %call2 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), double* %y.1)
>>> + ret void
>>> +}
>>> +
>>> +declare double @testi_aux()
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/escape-vector.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/escape-vector.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/escape-vector.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/escape-vector.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,21 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.vec = type { <4 x i32> }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a vector nested in a struct
>>> +; safestack attribute
>>> +; Requires protector.
>>> +define void @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %c = alloca %struct.vec, align 16
>>> + %y = getelementptr inbounds %struct.vec, %struct.vec* %c, i64 0, i32 0
>>> + %add.ptr = getelementptr inbounds <4 x i32>, <4 x i32>* %y, i64 -12
>>> + %call = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i64 0, i64 0), <4 x i32>* %add.ptr) nounwind
>>> + ret void
>>> +}
>>> +
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/invoke.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/invoke.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/invoke.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/invoke.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,33 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Addr-of a variable passed into an invoke instruction.
>>> +; safestack attribute
>>> +; Requires protector and stack restore after landing pad.
>>> +define i32 @foo() uwtable safestack {
>>> +entry:
>>> + ; CHECK: %[[SP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
>>> + ; CHECK: %[[STATICTOP:.*]] = getelementptr i8, i8* %[[SP]], i32 -16
>>> + %a = alloca i32, align 4
>>> + %exn.slot = alloca i8*
>>> + %ehselector.slot = alloca i32
>>> + store i32 0, i32* %a, align 4
>>> + invoke void @_Z3exceptPi(i32* %a)
>>> + to label %invoke.cont unwind label %lpad
>>> +
>>> +invoke.cont:
>>> + ret i32 0
>>> +
>>> +lpad:
>>> + ; CHECK: landingpad
>>> + ; CHECK-NEXT: catch
>>> + %0 = landingpad { i8*, i32 } personality i8* bitcast (i32 (...)* @__gxx_personality_v0 to i8*)
>>> + catch i8* null
>>> + ; CHECK-NEXT: store i8* %[[STATICTOP]], i8** @__safestack_unsafe_stack_ptr
>>> + ret i32 0
>>> +}
>>> +
>>> +declare void @_Z3exceptPi(i32*)
>>> +declare i32 @__gxx_personality_v0(...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/no-attr.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/no-attr.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/no-attr.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/no-attr.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,25 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; no safestack attribute
>>> +; Requires no protector.
>>> +
>>> +; CHECK: @foo
>>> +define void @foo(i8* %a) nounwind uwtable {
>>> +entry:
>>> + ; CHECK-NOT: __safestack_unsafe_stack_ptr
>>> + %a.addr = alloca i8*, align 8
>>> + %buf = alloca [16 x i8], align 16
>>> + store i8* %a, i8** %a.addr, align 8
>>> + %arraydecay = getelementptr inbounds [16 x i8], [16 x i8]* %buf, i32 0, i32 0
>>> + %0 = load i8*, i8** %a.addr, align 8
>>> + %call = call i8* @strcpy(i8* %arraydecay, i8* %0)
>>> + %arraydecay1 = getelementptr inbounds [16 x i8], [16 x i8]* %buf, i32 0, i32 0
>>> + %call2 = call i32 (i8*, ...) @printf(i8* getelementptr inbounds ([4 x i8], [4 x i8]* @.str, i32 0, i32 0), i8* %arraydecay1)
>>> + ret void
>>> +}
>>> +
>>> +declare i8* @strcpy(i8*, i8*)
>>> +declare i32 @printf(i8*, ...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/phi-cycle.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/phi-cycle.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/phi-cycle.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/phi-cycle.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,50 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.small = type { i8 }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; Address-of a structure taken in a function with a loop where
>>> +; the alloca is an incoming value to a PHI node and a use of that PHI
>>> +; node is also an incoming value.
>>> +; Verify that the address-of analysis does not get stuck in infinite
>>> +; recursion when chasing the alloca through the PHI nodes.
>>> +; Requires protector.
>>> +define i32 @foo(i32 %arg) nounwind uwtable safestack {
>>> +bb:
>>> + ; CHECK: __safestack_unsafe_stack_ptr
>>> + %tmp = alloca %struct.small*, align 8
>>> + %tmp1 = call i32 (...) @dummy(%struct.small** %tmp) nounwind
>>> + %tmp2 = load %struct.small*, %struct.small** %tmp, align 8
>>> + %tmp3 = ptrtoint %struct.small* %tmp2 to i64
>>> + %tmp4 = trunc i64 %tmp3 to i32
>>> + %tmp5 = icmp sgt i32 %tmp4, 0
>>> + br i1 %tmp5, label %bb6, label %bb21
>>> +
>>> +bb6: ; preds = %bb17, %bb
>>> + %tmp7 = phi %struct.small* [ %tmp19, %bb17 ], [ %tmp2, %bb ]
>>> + %tmp8 = phi i64 [ %tmp20, %bb17 ], [ 1, %bb ]
>>> + %tmp9 = phi i32 [ %tmp14, %bb17 ], [ %tmp1, %bb ]
>>> + %tmp10 = getelementptr inbounds %struct.small, %struct.small* %tmp7, i64 0, i32 0
>>> + %tmp11 = load i8, i8* %tmp10, align 1
>>> + %tmp12 = icmp eq i8 %tmp11, 1
>>> + %tmp13 = add nsw i32 %tmp9, 8
>>> + %tmp14 = select i1 %tmp12, i32 %tmp13, i32 %tmp9
>>> + %tmp15 = trunc i64 %tmp8 to i32
>>> + %tmp16 = icmp eq i32 %tmp15, %tmp4
>>> + br i1 %tmp16, label %bb21, label %bb17
>>> +
>>> +bb17: ; preds = %bb6
>>> + %tmp18 = getelementptr inbounds %struct.small*, %struct.small** %tmp, i64 %tmp8
>>> + %tmp19 = load %struct.small*, %struct.small** %tmp18, align 8
>>> + %tmp20 = add i64 %tmp8, 1
>>> + br label %bb6
>>> +
>>> +bb21: ; preds = %bb6, %bb
>>> + %tmp22 = phi i32 [ %tmp1, %bb ], [ %tmp14, %bb6 ]
>>> + %tmp23 = call i32 (...) @dummy(i32 %tmp22) nounwind
>>> + ret i32 undef
>>> +}
>>> +
>>> +declare i32 @dummy(...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/setjmp.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/setjmp.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/setjmp.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/setjmp.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,37 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.__jmp_buf_tag = type { [8 x i64], i32, %struct.__sigset_t }
>>> +%struct.__sigset_t = type { [16 x i64] }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> + at buf = internal global [1 x %struct.__jmp_buf_tag] zeroinitializer, align 16
>>> +
>>> +; setjmp/longjmp test.
>>> +; Requires protector.
>>> +define i32 @foo() nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: %[[SP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
>>> + ; CHECK: %[[STATICTOP:.*]] = getelementptr i8, i8* %[[SP]], i32 -16
>>> + %retval = alloca i32, align 4
>>> + %x = alloca i32, align 4
>>> + store i32 0, i32* %retval
>>> + store i32 42, i32* %x, align 4
>>> + %call = call i32 @_setjmp(%struct.__jmp_buf_tag* getelementptr inbounds ([1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* @buf, i32 0, i32 0)) returns_twice
>>> + ; CHECK: setjmp
>>> + ; CHECK-NEXT: store i8* %[[STATICTOP]], i8** @__safestack_unsafe_stack_ptr
>>> + %tobool = icmp ne i32 %call, 0
>>> + br i1 %tobool, label %if.else, label %if.then
>>> +if.then: ; preds = %entry
>>> + call void @funcall(i32* %x)
>>> + br label %if.end
>>> +if.else: ; preds = %entry
>>> + call i32 (...) @dummy()
>>> + br label %if.end
>>> +if.end: ; preds = %if.else, %if.then
>>> + ret i32 0
>>> +}
>>> +
>>> +declare i32 @_setjmp(%struct.__jmp_buf_tag*)
>>> +declare void @funcall(i32*)
>>> +declare i32 @dummy(...)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/setjmp2.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/setjmp2.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/setjmp2.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/setjmp2.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,42 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.__jmp_buf_tag = type { [8 x i64], i32, %struct.__sigset_t }
>>> +%struct.__sigset_t = type { [16 x i64] }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> + at buf = internal global [1 x %struct.__jmp_buf_tag] zeroinitializer, align 16
>>> +
>>> +; setjmp/longjmp test with dynamically sized array.
>>> +; Requires protector.
>>> +; CHECK: @foo(i32 %[[ARG:.*]])
>>> +define i32 @foo(i32 %size) nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: %[[DYNPTR:.*]] = alloca i8*
>>> + ; CHECK-NEXT: %[[SP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
>>> + ; CHECK-NEXT: store i8* %[[SP]], i8** %[[DYNPTR]]
>>> +
>>> + ; CHECK-NEXT: %[[ZEXT:.*]] = zext i32 %[[ARG]] to i64
>>> + ; CHECK-NEXT: %[[MUL:.*]] = mul i64 %[[ZEXT]], 4
>>> + ; CHECK-NEXT: %[[SP2:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
>>> + ; CHECK-NEXT: %[[PTRTOINT:.*]] = ptrtoint i8* %[[SP2]] to i64
>>> + ; CHECK-NEXT: %[[SUB:.*]] = sub i64 %[[PTRTOINT]], %[[MUL]]
>>> + ; CHECK-NEXT: %[[AND:.*]] = and i64 %[[SUB]], -16
>>> + ; CHECK-NEXT: %[[INTTOPTR:.*]] = inttoptr i64 %[[AND]] to i8*
>>> + ; CHECK-NEXT: store i8* %[[INTTOPTR]], i8** @__safestack_unsafe_stack_ptr
>>> + ; CHECK-NEXT: store i8* %[[INTTOPTR]], i8** %unsafe_stack_dynamic_ptr
>>> + ; CHECK-NEXT: %[[ALLOCA:.*]] = inttoptr i64 %[[SUB]] to i32*
>>> + %a = alloca i32, i32 %size
>>> +
>>> + ; CHECK: setjmp
>>> + ; CHECK-NEXT: %[[LOAD:.*]] = load i8*, i8** %[[DYNPTR]]
>>> + ; CHECK-NEXT: store i8* %[[LOAD]], i8** @__safestack_unsafe_stack_ptr
>>> + %call = call i32 @_setjmp(%struct.__jmp_buf_tag* getelementptr inbounds ([1 x %struct.__jmp_buf_tag], [1 x %struct.__jmp_buf_tag]* @buf, i32 0, i32 0)) returns_twice
>>> +
>>> + ; CHECK: call void @funcall(i32* %[[ALLOCA]])
>>> + call void @funcall(i32* %a)
>>> + ret i32 0
>>> +}
>>> +
>>> +declare i32 @_setjmp(%struct.__jmp_buf_tag*)
>>> +declare void @funcall(i32*)
>>>
>>> Added: llvm/trunk/test/Transforms/SafeStack/struct.ll
>>> URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/Transforms/SafeStack/struct.ll?rev=239761&view=auto
>>> ==============================================================================
>>> --- llvm/trunk/test/Transforms/SafeStack/struct.ll (added)
>>> +++ llvm/trunk/test/Transforms/SafeStack/struct.ll Mon Jun 15 16:07:11 2015
>>> @@ -0,0 +1,41 @@
>>> +; RUN: opt -safe-stack -S -mtriple=i386-pc-linux-gnu < %s -o - | FileCheck %s
>>> +; RUN: opt -safe-stack -S -mtriple=x86_64-pc-linux-gnu < %s -o - | FileCheck %s
>>> +
>>> +%struct.foo = type { [16 x i8] }
>>> +
>>> + at .str = private unnamed_addr constant [4 x i8] c"%s\0A\00", align 1
>>> +
>>> +; struct { [16 x i8] }
>>> +
>>> +define void @foo(i8* %a) nounwind uwtable safestack {
>>> +entry:
>>> + ; CHECK: %[[USP:.*]] = load i8*, i8** @__safestack_unsafe_stack_ptr
>>> +
>>> + ; CHECK: %[[USST:.*]] = getelementptr i8, i8* %[[USP]], i32 -16
>>> +
>>> + ; CHECK: store i8* %[[USST]], i8** @__safestack_unsafe_stack_ptr
>>> +
>>> + ; CHECK: %[[AADDR:.*]] = alloca i8*, align 8
>>> + %a.addr = alloca i8*, align 8
>>> +
>>> + ; CHECK: %[[BUFPTR:.*]] = getelementptr i8, i8* %[[USP]], i32 -16
>>> + ; CHECK: %[[BUFPTR2:.*]] = bitcast i8* %[[BUFPTR]] to %struct.foo*
>>> + %buf = alloca %struct.foo, align 1
>>> +
>>> + ; CHECK: store i8* {{.*}}, i8** %[[AADDR]], align 8
>>> + store i8* %a, i8** %a.addr, align 8
>>> +
>>> + ; CHECK: %[[GEP:.*]] = getelementptr inbounds %struct.foo, %struct.foo* %[[BUFPTR2]], i32 0, i32 0, i32 0
>>> + %gep = getelementptr inbounds %struct.foo, %struct.foo* %buf, i32 0, i32 0, i32 0
>>> +
>>> + ; CHECK: %[[A:.*]] = load i8*, i8** %[[AADDR]], align 8
>>> + %a2 = load i8*, i8** %a.addr, align 8
>>> +
>>> + ; CHECK: call i8* @strcpy(i8* %[[GEP]], i8* %[[A]])
>>> + %call = call i8* @strcpy(i8* %gep, i8* %a2)
>>> +
>>> + ; CHECK: store i8* %[[USP]], i8** @__safestack_unsafe_stack_ptr
>>> + ret void
>>> +}
>>> +
>>> +declare i8* @strcpy(i8*, i8*)
>>>
>>>
>>> _______________________________________________
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>>> llvm-commits at cs.uiuc.edu
>>> http://lists.cs.uiuc.edu/mailman/listinfo/llvm-commits
>>
>>
>
> --
> Peter
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