llvm-6502/test/CodeGen/PowerPC/noop-insert.ll
JF Bastien 21befa7761 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)

git-svn-id: https://llvm.org/svn/llvm-project/llvm/trunk@225908 91177308-0d34-0410-b5e6-96231b3b80d8
2015-01-14 01:07:26 +00:00

32 lines
838 B
LLVM

; 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
}