Files
llvm-project/compiler-rt/lib/scudo/scudo_termination.cpp
Kostya Kortchinsky 1148dc5274 [scudo] 32-bit and hardware agnostic support
Summary:
This update introduces i386 support for the Scudo Hardened Allocator, and
offers software alternatives for functions that used to require hardware
specific instruction sets. This should make porting to new architectures
easier.

Among the changes:
- The chunk header has been changed to accomodate the size limitations
  encountered on 32-bit architectures. We now fit everything in 64-bit. This
  was achieved by storing the amount of unused bytes in an allocation rather
  than the size itself, as one can be deduced from the other with the help
  of the GetActuallyAllocatedSize function. As it turns out, this header can
  be used for both 64 and 32 bit, and as such we dropped the requirement for
  the 128-bit compare and exchange instruction support (cmpxchg16b).
- Add 32-bit support for the checksum and the PRNG functions: if the SSE 4.2
  instruction set is supported, use the 32-bit CRC32 instruction, and in the
  XorShift128, use a 32-bit based state instead of 64-bit.
- Add software support for CRC32: if SSE 4.2 is not supported, fallback on a
  software implementation.
- Modify tests that were not 32-bit compliant, and expand them to cover more
  allocation and alignment sizes. The random shuffle test has been deactivated
  for linux-i386 & linux-i686 as the 32-bit sanitizer allocator doesn't
  currently randomize chunks.

Reviewers: alekseyshl, kcc

Subscribers: filcab, llvm-commits, tberghammer, danalbert, srhines, mgorny, modocache

Differential Revision: https://reviews.llvm.org/D26358

llvm-svn: 288255
2016-11-30 17:32:20 +00:00

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1.3 KiB
C++

//===-- scudo_termination.cpp -----------------------------------*- C++ -*-===//
//
// The LLVM Compiler Infrastructure
//
// This file is distributed under the University of Illinois Open Source
// License. See LICENSE.TXT for details.
//
//===----------------------------------------------------------------------===//
///
/// This file contains bare-bones termination functions to replace the
/// __sanitizer ones, in order to avoid any potential abuse of the callbacks
/// functionality.
///
//===----------------------------------------------------------------------===//
#include "scudo_utils.h"
#include "sanitizer_common/sanitizer_common.h"
namespace __sanitizer {
bool AddDieCallback(DieCallbackType Callback) { return true; }
bool RemoveDieCallback(DieCallbackType Callback) { return true; }
void SetUserDieCallback(DieCallbackType Callback) {}
void NORETURN Die() {
if (common_flags()->abort_on_error)
Abort();
internal__exit(common_flags()->exitcode);
}
void SetCheckFailedCallback(CheckFailedCallbackType callback) {}
void NORETURN CheckFailed(const char *File, int Line, const char *Condition,
u64 Value1, u64 Value2) {
__scudo::dieWithMessage("Scudo CHECK failed: %s:%d %s (%lld, %lld)\n",
File, Line, Condition, Value1, Value2);
}
} // namespace __sanitizer