[llvm] r225908 - Insert random noops to increase security against ROP attacks (llvm)
JF Bastien
jfb at google.com
Tue Jan 13 17:07:26 PST 2015
Author: jfb
Date: Tue Jan 13 19:07:26 2015
New Revision: 225908
URL: http://llvm.org/viewvc/llvm-project?rev=225908&view=rev
Log:
Insert random noops to increase security against ROP attacks (llvm)
A pass that adds random noops to X86 binaries to introduce diversity with the goal of increasing security against most return-oriented programming attacks.
Command line options:
-noop-insertion // Enable noop insertion.
-noop-insertion-percentage=X // X% of assembly instructions will have a noop prepended (default: 50%, requires -noop-insertion)
-max-noops-per-instruction=X // Randomly generate X noops per instruction. ie. roll the dice X times with probability set above (default: 1). This doesn't guarantee X noop instructions.
In addition, the following 'quick switch' in clang enables basic diversity using default settings (currently: noop insertion and schedule randomization; it is intended to be extended in the future).
-fdiversify
This is the llvm part of the patch.
clang part: D3393
http://reviews.llvm.org/D3392
Patch by Stephen Crane (@rinon)
Added:
llvm/trunk/include/llvm/CodeGen/NoopInsertion.h (with props)
llvm/trunk/lib/CodeGen/NoopInsertion.cpp (with props)
llvm/trunk/test/CodeGen/Mips/noop-insert.ll
llvm/trunk/test/CodeGen/PowerPC/noop-insert.ll
llvm/trunk/test/CodeGen/X86/noop-insert-percentage.ll
llvm/trunk/test/CodeGen/X86/noop-insert.ll
Modified:
llvm/trunk/include/llvm/CodeGen/CommandFlags.h
llvm/trunk/include/llvm/CodeGen/Passes.h
llvm/trunk/include/llvm/InitializePasses.h
llvm/trunk/include/llvm/Support/RandomNumberGenerator.h
llvm/trunk/include/llvm/Target/TargetInstrInfo.h
llvm/trunk/include/llvm/Target/TargetOptions.h
llvm/trunk/lib/CodeGen/CMakeLists.txt
llvm/trunk/lib/CodeGen/CodeGen.cpp
llvm/trunk/lib/CodeGen/Passes.cpp
llvm/trunk/lib/Target/X86/X86InstrInfo.cpp
llvm/trunk/lib/Target/X86/X86InstrInfo.h
Modified: llvm/trunk/include/llvm/CodeGen/CommandFlags.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/CommandFlags.h?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/CommandFlags.h (original)
+++ llvm/trunk/include/llvm/CodeGen/CommandFlags.h Tue Jan 13 19:07:26 2015
@@ -207,6 +207,12 @@ FunctionSections("function-sections",
cl::desc("Emit functions into separate sections"),
cl::init(false));
+cl::opt<bool>
+NoopInsertion("noop-insertion",
+ cl::desc("Randomly add Noop instructions to create fine-grained "
+ "code layout diversity."),
+ cl::init(false));
+
cl::opt<llvm::JumpTable::JumpTableType>
JTableType("jump-table-type",
cl::desc("Choose the type of Jump-Instruction Table for jumptable."),
@@ -284,6 +290,7 @@ static inline TargetOptions InitTargetOp
Options.UseInitArray = !UseCtors;
Options.DataSections = DataSections;
Options.FunctionSections = FunctionSections;
+ Options.NoopInsertion = NoopInsertion;
Options.MCOptions = InitMCTargetOptionsFromFlags();
Options.JTType = JTableType;
Added: llvm/trunk/include/llvm/CodeGen/NoopInsertion.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/NoopInsertion.h?rev=225908&view=auto
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/NoopInsertion.h (added)
+++ llvm/trunk/include/llvm/CodeGen/NoopInsertion.h Tue Jan 13 19:07:26 2015
@@ -0,0 +1,44 @@
+//===-- NoopInsertion.h - Noop Insertion ------------------------*- C++ -*-===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass adds fine-grained diversity by displacing code using randomly
+// placed (optionally target supplied) Noop instructions.
+//
+//===----------------------------------------------------------------------===//
+
+#ifndef LLVM_CODEGEN_NOOPINSERTION_H
+#define LLVM_CODEGEN_NOOPINSERTION_H
+
+#include "llvm/CodeGen/MachineFunctionPass.h"
+#include <random>
+
+namespace llvm {
+
+class RandomNumberGenerator;
+
+class NoopInsertion : public MachineFunctionPass {
+public:
+ static char ID;
+
+ NoopInsertion();
+
+private:
+ bool runOnMachineFunction(MachineFunction &MF) override;
+
+ void getAnalysisUsage(AnalysisUsage &AU) const override;
+
+ std::unique_ptr<RandomNumberGenerator> RNG;
+
+ // Uniform real distribution from 0 to 100
+ std::uniform_real_distribution<double> Distribution =
+ std::uniform_real_distribution<double>(0, 100);
+};
+}
+
+#endif // LLVM_CODEGEN_NOOPINSERTION_H
Propchange: llvm/trunk/include/llvm/CodeGen/NoopInsertion.h
------------------------------------------------------------------------------
svn:eol-style = LF
Modified: llvm/trunk/include/llvm/CodeGen/Passes.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/CodeGen/Passes.h?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/include/llvm/CodeGen/Passes.h (original)
+++ llvm/trunk/include/llvm/CodeGen/Passes.h Tue Jan 13 19:07:26 2015
@@ -603,6 +603,10 @@ namespace llvm {
/// the intrinsic for later emission to the StackMap.
extern char &StackMapLivenessID;
+ /// NoopInsertion - This pass adds fine-grained diversity by displacing code
+ /// using randomly placed (optionally target supplied) Noop instructions.
+ extern char &NoopInsertionID;
+
/// createJumpInstrTables - This pass creates jump-instruction tables.
ModulePass *createJumpInstrTablesPass();
Modified: llvm/trunk/include/llvm/InitializePasses.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/InitializePasses.h?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/include/llvm/InitializePasses.h (original)
+++ llvm/trunk/include/llvm/InitializePasses.h Tue Jan 13 19:07:26 2015
@@ -205,6 +205,7 @@ void initializeMetaRenamerPass(PassRegis
void initializeMergeFunctionsPass(PassRegistry&);
void initializeModuleDebugInfoPrinterPass(PassRegistry&);
void initializeNoAAPass(PassRegistry&);
+void initializeNoopInsertionPass(PassRegistry&);
void initializeObjCARCAliasAnalysisPass(PassRegistry&);
void initializeObjCARCAPElimPass(PassRegistry&);
void initializeObjCARCExpandPass(PassRegistry&);
Modified: llvm/trunk/include/llvm/Support/RandomNumberGenerator.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Support/RandomNumberGenerator.h?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Support/RandomNumberGenerator.h (original)
+++ llvm/trunk/include/llvm/Support/RandomNumberGenerator.h Tue Jan 13 19:07:26 2015
@@ -31,8 +31,20 @@ namespace llvm {
/// module.
class RandomNumberGenerator {
public:
+ typedef std::mt19937_64 RNG;
+ typedef RNG::result_type result_type;
+
/// Returns a random number in the range [0, Max).
- uint_fast64_t operator()();
+ result_type operator()();
+
+ // Must define min and max to be compatible with URNG as used by
+ // std::uniform_*_distribution
+ static LLVM_CONSTEXPR result_type min() {
+ return RNG::min();
+ }
+ static LLVM_CONSTEXPR result_type max() {
+ return RNG::max();
+ }
private:
/// Seeds and salts the underlying RNG engine.
@@ -45,7 +57,7 @@ private:
// http://en.cppreference.com/w/cpp/numeric/random/mersenne_twister_engine
// This RNG is deterministically portable across C++11
// implementations.
- std::mt19937_64 Generator;
+ RNG Generator;
// Noncopyable.
RandomNumberGenerator(const RandomNumberGenerator &other)
Modified: llvm/trunk/include/llvm/Target/TargetInstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetInstrInfo.h?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Target/TargetInstrInfo.h (original)
+++ llvm/trunk/include/llvm/Target/TargetInstrInfo.h Tue Jan 13 19:07:26 2015
@@ -32,6 +32,7 @@ class MDNode;
class MCInst;
struct MCSchedModel;
class MCSymbolRefExpr;
+class RandomNumberGenerator;
class SDNode;
class ScheduleHazardRecognizer;
class SelectionDAG;
@@ -875,6 +876,14 @@ public:
virtual void insertNoop(MachineBasicBlock &MBB,
MachineBasicBlock::iterator MI) const;
+ /// insertNoop - Insert a type of noop into the instruction stream at the
+ /// specified point to introduce fine-grained diversity. A target may randomly
+ /// choose from a pool of valid noops using the provided RNG.
+ virtual void insertNoop(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ RandomNumberGenerator&) const {
+ insertNoop(MBB, MI);
+ }
/// Return the noop instruction to use for a noop.
virtual void getNoopForMachoTarget(MCInst &NopInst) const;
Modified: llvm/trunk/include/llvm/Target/TargetOptions.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/include/llvm/Target/TargetOptions.h?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/include/llvm/Target/TargetOptions.h (original)
+++ llvm/trunk/include/llvm/Target/TargetOptions.h Tue Jan 13 19:07:26 2015
@@ -78,8 +78,8 @@ namespace llvm {
EnableFastISel(false), PositionIndependentExecutable(false),
UseInitArray(false), DisableIntegratedAS(false),
CompressDebugSections(false), FunctionSections(false),
- DataSections(false), TrapUnreachable(false), TrapFuncName(),
- FloatABIType(FloatABI::Default),
+ DataSections(false), NoopInsertion(false), TrapUnreachable(false),
+ TrapFuncName(), FloatABIType(FloatABI::Default),
AllowFPOpFusion(FPOpFusion::Standard), JTType(JumpTable::Single),
FCFI(false), ThreadModel(ThreadModel::POSIX),
CFIType(CFIntegrity::Sub), CFIEnforcing(false), CFIFuncName() {}
@@ -198,6 +198,10 @@ namespace llvm {
/// Emit data into separate sections.
unsigned DataSections : 1;
+ /// Randomly insert noop instructions to create fine-grained code
+ /// layout diversity.
+ unsigned NoopInsertion : 1;
+
/// Emit target-specific trap instruction for 'unreachable' IR instructions.
unsigned TrapUnreachable : 1;
Modified: llvm/trunk/lib/CodeGen/CMakeLists.txt
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/CMakeLists.txt?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/CMakeLists.txt (original)
+++ llvm/trunk/lib/CodeGen/CMakeLists.txt Tue Jan 13 19:07:26 2015
@@ -71,6 +71,7 @@ add_llvm_library(LLVMCodeGen
MachineSink.cpp
MachineTraceMetrics.cpp
MachineVerifier.cpp
+ NoopInsertion.cpp
OcamlGC.cpp
OptimizePHIs.cpp
PHIElimination.cpp
Modified: llvm/trunk/lib/CodeGen/CodeGen.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/CodeGen.cpp?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/CodeGen.cpp (original)
+++ llvm/trunk/lib/CodeGen/CodeGen.cpp Tue Jan 13 19:07:26 2015
@@ -51,6 +51,7 @@ void llvm::initializeCodeGen(PassRegistr
initializeMachineSchedulerPass(Registry);
initializeMachineSinkingPass(Registry);
initializeMachineVerifierPassPass(Registry);
+ initializeNoopInsertionPass(Registry);
initializeOptimizePHIsPass(Registry);
initializePHIEliminationPass(Registry);
initializePeepholeOptimizerPass(Registry);
Added: llvm/trunk/lib/CodeGen/NoopInsertion.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/NoopInsertion.cpp?rev=225908&view=auto
==============================================================================
--- llvm/trunk/lib/CodeGen/NoopInsertion.cpp (added)
+++ llvm/trunk/lib/CodeGen/NoopInsertion.cpp Tue Jan 13 19:07:26 2015
@@ -0,0 +1,101 @@
+//===- NoopInsertion.cpp - Noop Insertion ---------------------------------===//
+//
+// The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This pass adds fine-grained diversity by displacing code using randomly
+// placed (optionally target supplied) Noop instructions.
+//
+//===----------------------------------------------------------------------===//
+
+#include "llvm/CodeGen/NoopInsertion.h"
+#include "llvm/ADT/Statistic.h"
+#include "llvm/CodeGen/MachineInstrBuilder.h"
+#include "llvm/CodeGen/MachineModuleInfo.h"
+#include "llvm/CodeGen/MachineRegisterInfo.h"
+#include "llvm/CodeGen/Passes.h"
+#include "llvm/IR/BasicBlock.h"
+#include "llvm/IR/Function.h"
+#include "llvm/IR/Module.h"
+#include "llvm/Support/Allocator.h"
+#include "llvm/Support/CommandLine.h"
+#include "llvm/Support/RandomNumberGenerator.h"
+#include "llvm/Target/TargetInstrInfo.h"
+using namespace llvm;
+
+#define DEBUG_TYPE "noop-insertion"
+
+static cl::opt<unsigned> NoopInsertionPercentage(
+ "noop-insertion-percentage",
+ cl::desc("Percentage of instructions that have Noops prepended"),
+ cl::init(25)); // Default is a good balance between entropy and
+ // performance impact
+
+static cl::opt<unsigned> MaxNoopsPerInstruction(
+ "max-noops-per-instruction",
+ llvm::cl::desc("Maximum number of Noops per instruction"),
+ llvm::cl::init(1));
+
+STATISTIC(InsertedNoops,
+ "Total number of noop type instructions inserted for diversity");
+
+char NoopInsertion::ID = 0;
+char &llvm::NoopInsertionID = NoopInsertion::ID;
+INITIALIZE_PASS(NoopInsertion, "noop-insertion",
+ "Noop Insertion for fine-grained code randomization", false,
+ false)
+
+NoopInsertion::NoopInsertion() : MachineFunctionPass(ID) {
+ initializeNoopInsertionPass(*PassRegistry::getPassRegistry());
+
+ // clamp percentage to 100
+ if (NoopInsertionPercentage > 100)
+ NoopInsertionPercentage = 100;
+}
+
+void NoopInsertion::getAnalysisUsage(AnalysisUsage &AU) const {
+ AU.setPreservesCFG();
+ MachineFunctionPass::getAnalysisUsage(AU);
+}
+
+bool NoopInsertion::runOnMachineFunction(MachineFunction &Fn) {
+ // The RNG must be initialized on first use so we have a Module to
+ // construct it from
+ if (!RNG)
+ RNG.reset(Fn.getFunction()->getParent()->createRNG(this));
+
+ const TargetInstrInfo *TII = Fn.getSubtarget().getInstrInfo();
+
+ unsigned FnInsertedNoopCount = 0;
+
+ for (auto &BB : Fn) {
+ MachineBasicBlock::iterator FirstTerm = BB.getFirstTerminator();
+
+ for (MachineBasicBlock::iterator I = BB.begin(), E = BB.end(); I != E;
+ ++I) {
+ if (I->isPseudo())
+ continue;
+
+ // Insert random number of Noop-like instructions.
+ for (unsigned i = 0; i < MaxNoopsPerInstruction; i++) {
+ if (Distribution(*RNG) >= NoopInsertionPercentage)
+ continue;
+
+ TII->insertNoop(BB, I, *RNG);
+
+ ++FnInsertedNoopCount;
+ }
+
+ if (I == FirstTerm)
+ break;
+ }
+ }
+
+ InsertedNoops += FnInsertedNoopCount;
+
+ return FnInsertedNoopCount > 0;
+}
Propchange: llvm/trunk/lib/CodeGen/NoopInsertion.cpp
------------------------------------------------------------------------------
svn:eol-style = LF
Modified: llvm/trunk/lib/CodeGen/Passes.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/CodeGen/Passes.cpp?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/lib/CodeGen/Passes.cpp (original)
+++ llvm/trunk/lib/CodeGen/Passes.cpp Tue Jan 13 19:07:26 2015
@@ -583,6 +583,9 @@ void TargetPassConfig::addMachinePasses(
addPass(createGCInfoPrinter(dbgs()), false, false);
}
+ if (TM->Options.NoopInsertion)
+ addPass(&NoopInsertionID);
+
// Basic block placement.
if (getOptLevel() != CodeGenOpt::None)
addBlockPlacement();
Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.cpp?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.cpp (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.cpp Tue Jan 13 19:07:26 2015
@@ -34,6 +34,7 @@
#include "llvm/Support/CommandLine.h"
#include "llvm/Support/Debug.h"
#include "llvm/Support/ErrorHandling.h"
+#include "llvm/Support/RandomNumberGenerator.h"
#include "llvm/Support/raw_ostream.h"
#include "llvm/Target/TargetOptions.h"
#include <limits>
@@ -5620,6 +5621,66 @@ void X86InstrInfo::setExecutionDomain(Ma
MI->setDesc(get(table[Domain-1]));
}
+/// insertNoop - Insert a noop into the instruction stream at the specified
+/// point.
+void X86InstrInfo::insertNoop(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI) const {
+ DebugLoc DL;
+ BuildMI(MBB, MI, DL, get(X86::NOOP));
+}
+
+/// insertNoop - Insert a randomly chosen type of noop into the instruction
+/// stream at the specified point to introduce fine-grained diversity.
+void X86InstrInfo::insertNoop(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ RandomNumberGenerator &RNG) const {
+ // This set of Noop instructions was carefully chosen so that
+ // misaligned parses of these instructions do not introduce new,
+ // useful ROP gadgets. The ASM instructions noted are for misaligned
+ // parses of the noop in 32 and 64 bits.
+ enum {
+ NOP, // 90
+ MOV_BP, // 89 ed, 48 89 ed -- IN EAX, IN AL (privileged)
+ MOV_SP, // 89 e4, 48 89 e4 -- IN AL, IN EAX (privileged)
+ LEA_SI, // 8d 36, 48 8d 36 -- SS segment override, NULL
+ // prefix (does not add new gadget)
+ LEA_DI, // 8d 3f, 48 8d 3f -- AAS (bcd->hex), invalid
+ MAX_NOPS
+ };
+
+ static const unsigned NopRegs[MAX_NOPS][2] = {
+ {0, 0},
+ {X86::EBP, X86::RBP},
+ {X86::ESP, X86::RSP},
+ {X86::ESI, X86::RSI},
+ {X86::EDI, X86::RDI},
+ };
+
+ std::uniform_int_distribution<unsigned> Distribution(0, MAX_NOPS - 1);
+
+ unsigned Type = Distribution(RNG);
+
+ DebugLoc DL;
+ bool is64Bit = Subtarget.is64Bit();
+ unsigned Reg = NopRegs[Type][is64Bit];
+
+ switch (Type) {
+ case NOP:
+ BuildMI(MBB, MI, DL, get(X86::NOOP));
+ break;
+ case MOV_BP:
+ case MOV_SP:
+ copyPhysReg(MBB, MI, DL, Reg, Reg, false);
+ break;
+ case LEA_SI:
+ case LEA_DI: {
+ unsigned opc = is64Bit ? X86::LEA64r : X86::LEA32r;
+ addRegOffset(BuildMI(MBB, MI, DL, get(opc), Reg), Reg, false, 0);
+ break;
+ }
+ }
+}
+
/// getNoopForMachoTarget - Return the noop instruction to use for a noop.
void X86InstrInfo::getNoopForMachoTarget(MCInst &NopInst) const {
NopInst.setOpcode(X86::NOOP);
Modified: llvm/trunk/lib/Target/X86/X86InstrInfo.h
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/lib/Target/X86/X86InstrInfo.h?rev=225908&r1=225907&r2=225908&view=diff
==============================================================================
--- llvm/trunk/lib/Target/X86/X86InstrInfo.h (original)
+++ llvm/trunk/lib/Target/X86/X86InstrInfo.h Tue Jan 13 19:07:26 2015
@@ -361,6 +361,13 @@ public:
bool shouldScheduleAdjacent(MachineInstr* First,
MachineInstr *Second) const override;
+ void insertNoop(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI) const override;
+
+ void insertNoop(MachineBasicBlock &MBB,
+ MachineBasicBlock::iterator MI,
+ RandomNumberGenerator &RNG) const override;
+
void getNoopForMachoTarget(MCInst &NopInst) const override;
bool
Added: llvm/trunk/test/CodeGen/Mips/noop-insert.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/Mips/noop-insert.ll?rev=225908&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/Mips/noop-insert.ll (added)
+++ llvm/trunk/test/CodeGen/Mips/noop-insert.ll Tue Jan 13 19:07:26 2015
@@ -0,0 +1,26 @@
+; RUN: llc < %s -march=mips -noop-insertion | FileCheck %s
+; RUN: llc < %s -march=mips -noop-insertion -rng-seed=1 | FileCheck %s --check-prefix=SEED1
+; RUN: llc < %s -march=mips -noop-insertion -noop-insertion-percentage=100 | FileCheck %s --check-prefix=100PERCENT
+
+; This test case checks that NOOPs are inserted correctly for MIPS.
+
+; It just happens that with a default percentage of 25% and seed=0,
+; no NOOPs are inserted.
+; CHECK: mul
+; CHECK-NEXT: jr
+
+; SEED1: nop
+; SEED1-NEXT: mul
+; SEED1-NEXT: jr
+
+; 100PERCENT: nop
+; 100PERCENT-NEXT: mul
+; 100PERCENT-NEXT: nop
+; 100PERCENT-NEXT: jr
+
+define i32 @test1(i32 %x, i32 %y, i32 %z) {
+entry:
+ %tmp = mul i32 %x, %y
+ %tmp2 = add i32 %tmp, %z
+ ret i32 %tmp2
+}
Added: llvm/trunk/test/CodeGen/PowerPC/noop-insert.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/PowerPC/noop-insert.ll?rev=225908&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/PowerPC/noop-insert.ll (added)
+++ llvm/trunk/test/CodeGen/PowerPC/noop-insert.ll Tue Jan 13 19:07:26 2015
@@ -0,0 +1,31 @@
+; RUN: llc < %s -march=ppc32 -noop-insertion | FileCheck %s
+; RUN: llc < %s -march=ppc32 -noop-insertion -rng-seed=1 | FileCheck %s --check-prefix=SEED1
+; RUN: llc < %s -march=ppc32 -noop-insertion -noop-insertion-percentage=100 | FileCheck %s --check-prefix=100PERCENT
+
+; This test case checks that NOOPs are inserted correctly for PowerPC.
+
+; It just happens that with a default percentage of 25% and seed=0,
+; no NOOPs are inserted.
+; CHECK: mullw
+; CHECK-NEXT: add
+; CHECK-NEXT: blr
+
+; SEED1: nop
+; SEED1-NEXT: mullw
+; SEED1-NEXT: add
+; SEED1-NEXT: nop
+; SEED1-NEXT: blr
+
+; 100PERCENT: nop
+; 100PERCENT-NEXT: mullw
+; 100PERCENT-NEXT: nop
+; 100PERCENT-NEXT: add
+; 100PERCENT-NEXT: nop
+; 100PERCENT-NEXT: blr
+
+define i32 @test1(i32 %x, i32 %y, i32 %z) {
+entry:
+ %tmp = mul i32 %x, %y
+ %tmp2 = add i32 %tmp, %z
+ ret i32 %tmp2
+}
Added: llvm/trunk/test/CodeGen/X86/noop-insert-percentage.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/noop-insert-percentage.ll?rev=225908&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/noop-insert-percentage.ll (added)
+++ llvm/trunk/test/CodeGen/X86/noop-insert-percentage.ll Tue Jan 13 19:07:26 2015
@@ -0,0 +1,66 @@
+; RUN: llc < %s -mtriple=x86_64-linux -rng-seed=5 -noop-insertion -noop-insertion-percentage=10 \
+; RUN: | FileCheck %s --check-prefix=PERCENT10
+; RUN: llc < %s -mtriple=x86_64-linux -rng-seed=5 -noop-insertion -noop-insertion-percentage=50 \
+; RUN: | FileCheck %s --check-prefix=PERCENT50
+; RUN: llc < %s -mtriple=x86_64-linux -rng-seed=5 -noop-insertion -noop-insertion-percentage=100 \
+; RUN: | FileCheck %s --check-prefix=PERCENT100
+
+; RUN: llc < %s -march=x86 -rng-seed=5 -noop-insertion -noop-insertion-percentage=100 \
+; RUN: | FileCheck %s --check-prefix=X86-PERCENT100
+
+; This test case tests NOOP insertion at varying percentage levels.
+
+define i32 @test(i32 %x, i32 %y, i32 %z) {
+entry:
+ %t1 = add i32 %x, %y
+ %t2 = mul i32 %t1, %z
+ %t3 = add i32 %t2, %x
+ %t4 = mul i32 %t3, %z
+ %t5 = add i32 %t4, %x
+ %t6 = mul i32 %t5, %z
+ %t7 = add i32 %t6, %x
+ %t8 = mul i32 %t7, %z
+ %t9 = add i32 %t8, %x
+ %t10 = mul i32 %t9, %z
+ %t11 = add i32 %t10, %x
+ ret i32 %t11
+}
+
+; PERCENT10: movq %rbp, %rbp
+; PERCENT10: retq
+
+; PERCENT50: leaq (%rdi), %rdi
+; PERCENT50: nop
+; PERCENT50: movq %rbp, %rbp
+; PERCENT50: movq %rsp, %rsp
+; PERCENT50: leaq (%rsi), %rsi
+; PERCENT50: nop
+; PERCENT50: retq
+
+; PERCENT100: leaq (%rdi), %rdi
+; PERCENT100: leaq (%rdi), %rdi
+; PERCENT100: nop
+; PERCENT100: movq %rbp, %rbp
+; PERCENT100: movq %rsp, %rsp
+; PERCENT100: nop
+; PERCENT100: nop
+; PERCENT100: leaq (%rsi), %rsi
+; PERCENT100: nop
+; PERCENT100: leaq (%rdi), %rdi
+; PERCENT100: leaq (%rdi), %rdi
+; PERCENT100: leaq (%rsi), %rsi
+; PERCENT100: retq
+
+
+; X86-PERCENT100: leal (%edi), %edi
+; X86-PERCENT100: leal (%edi), %edi
+; X86-PERCENT100: nop
+; X86-PERCENT100: movl %ebp, %ebp
+; X86-PERCENT100: movl %esp, %esp
+; X86-PERCENT100: nop
+; X86-PERCENT100: nop
+; X86-PERCENT100: leal (%esi), %esi
+; X86-PERCENT100: nop
+; X86-PERCENT100: leal (%edi), %edi
+; X86-PERCENT100: leal (%edi), %edi
+; X86-PERCENT100: leal (%esi), %esi
Added: llvm/trunk/test/CodeGen/X86/noop-insert.ll
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/test/CodeGen/X86/noop-insert.ll?rev=225908&view=auto
==============================================================================
--- llvm/trunk/test/CodeGen/X86/noop-insert.ll (added)
+++ llvm/trunk/test/CodeGen/X86/noop-insert.ll Tue Jan 13 19:07:26 2015
@@ -0,0 +1,46 @@
+; RUN: llc < %s -mtriple=x86_64-linux -noop-insertion | FileCheck %s
+; RUN: llc < %s -mtriple=x86_64-linux -noop-insertion -rng-seed=1 | FileCheck %s --check-prefix=SEED1
+; RUN: llc < %s -mtriple=x86_64-linux -noop-insertion -rng-seed=20 | FileCheck %s --check-prefix=SEED2
+; RUN: llc < %s -mtriple=x86_64-linux -noop-insertion -rng-seed=500 | FileCheck %s --check-prefix=SEED3
+
+; RUN: llc < %s -march=x86 -noop-insertion | FileCheck %s --check-prefix=x86_32
+
+; This test case checks that NOOPs are inserted, and that the RNG seed
+; affects both the placement (position of imull) and choice of these NOOPs.
+
+; It just happens that with a default percentage of 25% and seed=0,
+; no NOOPs are inserted.
+; CHECK: imull
+; CHECK-NEXT: leal
+; CHECK-NEXT: retq
+; CHECK-NOT: nop
+
+; SEED1: leaq (%rsi), %rsi
+; SEED1-NEXT: imull
+; SEED1-NEXT: leal
+; SEED1-NEXT: retq
+
+; SEED2: imull
+; SEED2-NEXT: movq %rsp, %rsp
+; SEED2-NEXT: leal
+; SEED2-NEXT: retq
+
+; SEED3: imull
+; SEED3-NEXT: movq %rsp, %rsp
+; SEED3-NEXT: leal
+; SEED3-NEXT: leaq (%rdi), %rdi
+; SEED3-NEXT: retq
+
+; The operand of the following is used to distinguish from a movl NOOP
+; x86_32: movl 4(%esp),
+; x86_32-NEXT: imull
+; x86_32-NEXT: addl
+; x86_32-NEXT: movl %esp, %esp
+; x86_32-NEXT: retl
+
+define i32 @test1(i32 %x, i32 %y, i32 %z) {
+entry:
+ %tmp = mul i32 %x, %y
+ %tmp2 = add i32 %tmp, %z
+ ret i32 %tmp2
+}
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