lto module clean-up (#303)

This commit is contained in:
van Hauser
2020-04-09 13:13:07 +02:00
committed by GitHub
parent d55196352c
commit e354235ebb

View File

@ -23,12 +23,6 @@
*/
// CONFIG OPTION:
// If #define USE_SPLIT is used, then the llvm::SplitEdge function is used
// instead of our own implementation. Ours looks better and will
// compile everywhere. But it is not working for complex code. yet. damn.
#define USE_SPLIT
#define AFL_LLVM_PASS
#include "config.h"
@ -44,31 +38,17 @@
#include <sys/time.h>
#include "llvm/Config/llvm-config.h"
#if LLVM_VERSION_MAJOR == 3 && LLVM_VERSION_MINOR < 5
typedef long double max_align_t;
#endif
#include "llvm/IR/IRBuilder.h"
#include "llvm/IR/LegacyPassManager.h"
#include "llvm/IR/BasicBlock.h"
#include "llvm/IR/Module.h"
#include "llvm/Support/Debug.h"
#include "llvm/Transforms/IPO/PassManagerBuilder.h"
#ifdef USE_SPLIT
#include "llvm/Transforms/Utils/BasicBlockUtils.h"
#include "llvm/Analysis/LoopInfo.h"
#include "llvm/Analysis/MemorySSAUpdater.h"
#endif
#if LLVM_VERSION_MAJOR > 3 || \
(LLVM_VERSION_MAJOR == 3 && LLVM_VERSION_MINOR > 4)
#include "llvm/IR/DebugInfo.h"
#include "llvm/IR/CFG.h"
#else
#include "llvm/DebugInfo.h"
#include "llvm/Support/CFG.h"
#endif
using namespace llvm;
@ -91,7 +71,6 @@ class AFLLTOPass : public ModulePass {
}
#ifdef USE_SPLIT
void getAnalysisUsage(AnalysisUsage &AU) const override {
ModulePass::getAnalysisUsage(AU);
@ -100,8 +79,6 @@ class AFLLTOPass : public ModulePass {
}
#endif
// Calculate the number of average collisions that would occur if all
// location IDs would be assigned randomly (like normal afl/afl++).
// This uses the "balls in bins" algorithm.
@ -181,18 +158,12 @@ bool AFLLTOPass::runOnModule(Module &M) {
IntegerType *Int8Ty = IntegerType::getInt8Ty(C);
IntegerType *Int32Ty = IntegerType::getInt32Ty(C);
struct timeval tv;
struct timezone tz;
u32 rand_seed;
/* Setup random() so we get Actually Random(TM) outputs from AFL_R() */
gettimeofday(&tv, &tz);
rand_seed = tv.tv_sec ^ tv.tv_usec ^ getpid();
AFL_SR(rand_seed);
if (getenv("AFL_DEBUG")) debug = 1;
/* Show a banner */
if ((isatty(2) && !getenv("AFL_QUIET")) || getenv("AFL_DEBUG") != NULL) {
if ((isatty(2) && !getenv("AFL_QUIET")) || debug) {
SAYF(cCYA "afl-llvm-lto" VERSION cRST
" by Marc \"vanHauser\" Heuse <mh@mh-sec.de>\n");
@ -201,10 +172,6 @@ bool AFLLTOPass::runOnModule(Module &M) {
be_quiet = 1;
#if LLVM_VERSION_MAJOR < 9
char *neverZero_counters_str = getenv("AFL_LLVM_NOT_ZERO");
#endif
/* Get globals for the SHM region and the previous location. Note that
__afl_prev_loc is thread-local. */
@ -224,12 +191,6 @@ bool AFLLTOPass::runOnModule(Module &M) {
if (F.size() < 2) continue;
if (isBlacklisted(&F)) continue;
#ifdef USE_SPLIT
// DominatorTree &DT =
// getAnalysis<DominatorTreeWrapperPass>(F).getDomTree(); LoopInfo & LI =
// getAnalysis<LoopInfoWrapperPass>(F).getLoopInfo();
#endif
std::vector<BasicBlock *> InsBlocks;
for (auto &BB : F) {
@ -274,11 +235,7 @@ bool AFLLTOPass::runOnModule(Module &M) {
for (uint32_t j = 0; j < Successors.size(); j++) {
#ifdef USE_SPLIT
BasicBlock *newBB = llvm::SplitEdge(origBB, Successors[j]);
#else
BasicBlock *newBB = BasicBlock::Create(C, "", &F, nullptr);
#endif
if (!newBB) {
@ -287,12 +244,8 @@ bool AFLLTOPass::runOnModule(Module &M) {
}
#ifdef USE_SPLIT
BasicBlock::iterator IP = newBB->getFirstInsertionPt();
IRBuilder<> IRB(&(*IP));
#else
IRBuilder<> IRB(&(*newBB));
#endif
/* Set the ID of the inserted basic block */
@ -313,38 +266,12 @@ bool AFLLTOPass::runOnModule(Module &M) {
Value *Incr = IRB.CreateAdd(Counter, One);
#if LLVM_VERSION_MAJOR < 9
if (neverZero_counters_str !=
NULL) { // with llvm 9 we make this the default as the bug in
// llvm is then fixed
#endif
auto cf = IRB.CreateICmpEQ(Incr, Zero);
auto carry = IRB.CreateZExt(cf, Int8Ty);
Incr = IRB.CreateAdd(Incr, carry);
#if LLVM_VERSION_MAJOR < 9
}
#endif
IRB.CreateStore(Incr, MapPtrIdx)
->setMetadata(M.getMDKindID("nosanitize"), MDNode::get(C, None));
#ifdef USE_SPLIT
// nothing
#else
// Unconditional jump to the destination BB
IRB.CreateBr(Successors[j]);
// Replace the original destination to this newly inserted BB
origBB->replacePhiUsesWith(Successors[j], newBB);
BasicBlock *S = Successors[j];
S->replacePhiUsesWith(origBB, newBB);
TI->setSuccessor(j, newBB);
#endif
// done :)
inst_blocks++;