From 6cc8ee707c1b4337120aa2972e2ad13a4861bbc3 Mon Sep 17 00:00:00 2001 From: Frank Busse Date: Mon, 13 Jun 2022 10:42:51 +0100 Subject: remove LLVM < 9 --- cmake/workaround_llvm_pr39177.cmake | 133 ------------------------------------ cmake/workaround_llvm_pr39177.ll | 18 ----- 2 files changed, 151 deletions(-) delete mode 100644 cmake/workaround_llvm_pr39177.cmake delete mode 100644 cmake/workaround_llvm_pr39177.ll (limited to 'cmake') diff --git a/cmake/workaround_llvm_pr39177.cmake b/cmake/workaround_llvm_pr39177.cmake deleted file mode 100644 index 9e0ac8bd..00000000 --- a/cmake/workaround_llvm_pr39177.cmake +++ /dev/null @@ -1,133 +0,0 @@ -# Workaround for LLVM PR39177 -# - https://bugs.llvm.org/show_bug.cgi?id=39177 -# - https://github.com/klee/klee/issues/1000 -# -# TODO: remove when support for LLVM <= 7 is dropped -# -# Short description of the bug: -# The LLVM pass `-instcombine` optimizes calls to C standard lib functions by, -# e.g. transforming the following call to a call to fwrite(): -# fprintf(stderr, "hello world!\n"); -# In uClibc, and thus klee-uclibc, fwrite() is defined as an alias to a function -# fwrite_unlocked(). This translates to a GlobalAlias in LLVM IR. When trying to -# infer function attributes from fwrite(), LLVM tries to cast a GlobalAlias to a -# Function, which results in a null-pointer dereference. When calling KLEE with -# `-optimize`, this leads to a crash of KLEE. -# -# This bug affects LLVM 3.9 - 7.0.0. -# -# As the bug results in a null-pointer dereference when trying to access a -# Function that is only available as GlobalAlias, this workaround introduces a -# pass into KLEE that replaces aliases for certain C standard lib function with -# clones of the corresponding aliasee function. -# -# The bug was fixed in the following commits in LLVM: -# - https://reviews.llvm.org/rL344454 -# - https://reviews.llvm.org/rL344455 -# - https://reviews.llvm.org/rL344645 -# These patches were then applied to the release_70 branch to land in 7.0.1: -# - https://reviews.llvm.org/rL345921 -# -# This CMake file checks whether the method responsible for the null-pointer -# dereference leads to a crash of the program given in this file. -# -# Files that were created/modified for this workaround: -# [NEW FILE] cmake/workaround_llvm_pr39177.cmake (this file) -# [NEW FILE] cmake/workaround_llvm_pr39177.ll (auxiliary file for feature test) -# [NEW FILE] lib/Module/WorkaroundLLVMPR39177.cpp -# -# [MODIFIED] CMakeLists.txt (including this file) -# [MODIFIED] include/klee/Config/config.h.cmin (cmakedefine) -# [MODIFIED] lib/Module/CMakeLists.txt -# [MODIFIED] lib/Module/Optimize.cpp (add pass during optimization) -# [MODIFIED] lib/Module/Passes.h - -# Detect whether LLVM version is affected by PR39177 -if (${LLVM_VERSION_MAJOR} LESS 7 OR (${LLVM_VERSION_MAJOR} EQUAL 7 AND ${LLVM_VERSION_MINOR} EQUAL 0 AND ${LLVM_VERSION_PATCH} EQUAL 0)) # LLVM <= 7.0.0 - set(DISABLE_WORKAROUND_LLVM_PR39177_DEFAULT OFF) -else() - set(DISABLE_WORKAROUND_LLVM_PR39177_DEFAULT ON) -endif() - -option(DISABLE_WORKAROUND_LLVM_PR39177 "Disable Workaround for LLVM PR39177 (affecting LLVM 3.9 - 7.0.0)" ${DISABLE_WORKAROUND_LLVM_PR39177_DEFAULT}) - -if (NOT DISABLE_WORKAROUND_LLVM_PR39177) - # Detect whether PR39177 leads to crash - include(CheckCXXSourceRuns) - - cmake_push_check_state() - klee_get_llvm_libs(LLVM_LIBS asmparser transformutils) - set(CMAKE_REQUIRED_INCLUDES "${LLVM_INCLUDE_DIRS}") - set(CMAKE_REQUIRED_LIBRARIES "${LLVM_LIBS}") - - check_cxx_source_runs(" - #include \"llvm/Analysis/TargetLibraryInfo.h\" - #include \"llvm/AsmParser/Parser.h\" - #include \"llvm/AsmParser/SlotMapping.h\" - #include \"llvm/IR/ConstantFolder.h\" - #include \"llvm/IR/Constants.h\" - #include \"llvm/IR/DataLayout.h\" - #include \"llvm/IR/DiagnosticInfo.h\" - #include \"llvm/IR/Instructions.h\" - #include \"llvm/IR/IRBuilder.h\" - #include \"llvm/IR/LLVMContext.h\" - #include \"llvm/Transforms/Utils/BuildLibCalls.h\" - - #include - - void handler(int, siginfo_t*, void*) { - // program received SIGSEGV - exit(1); - } - - using namespace llvm; - - int main() { - // capture segfault - struct sigaction action; - memset(&action, 0, sizeof(struct sigaction)); - action.sa_flags = SA_SIGINFO; - action.sa_sigaction = handler; - sigaction(SIGSEGV, &action, NULL); - - // setup test - LLVMContext Ctx; - SMDiagnostic Error; - SlotMapping Mapping; - auto M = llvm::parseAssemblyFile(\"${CMAKE_SOURCE_DIR}/cmake/workaround_llvm_pr39177.ll\", Error, Ctx, &Mapping); - if (!M) { - Error.print(\"AssemblyString\", llvm::errs()); - return -1; - } - - auto *F = M->getFunction(\"test\"); - auto *CI = cast(&*std::next(F->begin()->begin())); - auto &DL = M->getDataLayout(); - Value *Size = ConstantInt::get(DL.getIntPtrType(Ctx), 8); - ConstantFolder CF; - IRBuilder<> B(&*F->begin(), CF); - TargetLibraryInfo TLI = TargetLibraryInfoWrapperPass({\"x86_64\", \"\", \"linux-gnu\"}).getTLI(); - - // test if this call produces segfault - emitFWrite(CI->getArgOperand(1), Size, CI->getArgOperand(0), B, DL, &TLI); - - return 0; - }" - LLVM_PR39177_FIXED - ) - cmake_pop_check_state() - - if (NOT LLVM_PR39177_FIXED) - message(STATUS "Workaround for LLVM PR39177 (affecting LLVM 3.9 - 7.0.0) enabled") - set(USE_WORKAROUND_LLVM_PR39177 1) # For config.h - else() - message(FATAL_ERROR "DISABLE_WORKAROUND_LLVM_PR39177 is not set to true" - "but crash resulting from PR39177 could not be detected." - "You may try to disable the workaround using" - "-DDISABLE_WORKAROUND_LLVM_PR39177=1 if you believe the issue is patched" - "in your version of LLVM.") - endif() -else() - message(STATUS "Workaround for LLVM PR39177 (affecting LLVM 3.9 - 7.0.0) disabled") - unset(USE_WORKAROUND_LLVM_PR39177) # For config.h -endif() diff --git a/cmake/workaround_llvm_pr39177.ll b/cmake/workaround_llvm_pr39177.ll deleted file mode 100644 index ebca4f1c..00000000 --- a/cmake/workaround_llvm_pr39177.ll +++ /dev/null @@ -1,18 +0,0 @@ -%struct._IO_FILE = type { i32, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, i8*, %struct._IO_marker*, %struct._IO_FILE*, i32, i32, i64, i16, i8, [1 x i8], i8*, i64, i8*, i8*, i8*, i8*, i64, i32, [20 x i8] } -%struct._IO_marker = type { %struct._IO_marker*, %struct._IO_FILE*, i32 } - -@stdout = external global %struct._IO_FILE*, align 8 -@.str = private unnamed_addr constant [11 x i8] c"abcdefgh!\0A\00", align 1 -@fwrite = alias i64 (i8*, i64, i64, %struct._IO_FILE*), i64 (i8*, i64, i64, %struct._IO_FILE*)* @__fwrite_alias - -define i64 @__fwrite_alias(i8*, i64, i64, %struct._IO_FILE*) { - ret i64 0 -} - -define void @test() { - %1 = load %struct._IO_FILE*, %struct._IO_FILE** @stdout, align 8 - %2 = call i32 (%struct._IO_FILE*, i8*, ...) @fprintf(%struct._IO_FILE* %1, i8* getelementptr inbounds ([11 x i8], [11 x i8]* @.str, i32 0, i32 0)) - ret void -} - -declare i32 @fprintf(%struct._IO_FILE*, i8*, ...) -- cgit 1.4.1