[all-commits] [llvm/llvm-project] f85002: [sanitizer] Implement MapDynamicShadowAndAliases.

[Matt Morehouse via All-commits]

  Branch: refs/heads/main
  Home:   https://github.com/llvm/llvm-project
  Commit: f85002d22c6bcaa5f870bc56be3b4e8f97769480
      https://github.com/llvm/llvm-project/commit/f85002d22c6bcaa5f870bc56be3b4e8f97769480
  Author: Matt Morehouse <mascasa at google.com>
  Date:   2021-03-23 (Tue, 23 Mar 2021)

  Changed paths:
    M compiler-rt/lib/sanitizer_common/sanitizer_common.h
    M compiler-rt/lib/sanitizer_common/sanitizer_linux.cpp
    M compiler-rt/lib/sanitizer_common/sanitizer_linux_libcdep.cpp
    M compiler-rt/lib/sanitizer_common/sanitizer_mac.cpp
    M compiler-rt/lib/sanitizer_common/sanitizer_netbsd.cpp
    M compiler-rt/lib/sanitizer_common/sanitizer_posix.h
    M compiler-rt/lib/sanitizer_common/sanitizer_win.cpp

  Log Message:
  -----------
  [sanitizer] Implement MapDynamicShadowAndAliases.

The function works like MapDynamicShadow, except that it creates aliased
memory to the right of the shadow.  The main use case is for HWASan
aliasing mode, which gets fast IsAlias() checks by exploiting the fact
that the upper bits of the shadow base and aliased memory match.

Reviewed By: vitalybuka, eugenis

Differential Revision: https://reviews.llvm.org/D98369