Commit Graph

6 Commits

Author SHA1 Message Date
Rafael Espindola 922f2aa9b2 Bring r325915 back.
The tests that failed on a windows host have been fixed.

Original message:

Start setting dso_local for COFF.

With this there are still some GVs where we don't set dso_local
because setGVProperties is never called. I intend to fix that in
followup commits. This is just the bare minimum to teach
shouldAssumeDSOLocal what it should do for COFF.

llvm-svn: 325940
2018-02-23 19:30:48 +00:00
Vedant Kumar bbc953fed4 [ubsan] Null-check pointers in -fsanitize=vptr (PR33881)
The instrumentation generated by -fsanitize=vptr does not null check a
user pointer before loading from it. This causes crashes in the face of
UB member calls (this=nullptr), i.e it's causing user programs to crash
only after UBSan is turned on.

The fix is to make run-time null checking a prerequisite for enabling
-fsanitize=vptr, and to then teach UBSan to reuse these run-time null
checks to make -fsanitize=vptr safe.

Testing: check-clang, check-ubsan, a stage2 ubsan-enabled build

Differential Revision: https://reviews.llvm.org/D35735

https://bugs.llvm.org/show_bug.cgi?id=33881

llvm-svn: 309007
2017-07-25 19:34:23 +00:00
Vedant Kumar 2d38ae6c41 [CodeGen] Devirtualize calls to methods marked final in a derived class
If we see a virtual method call to Base::foo() but can infer that the
object is an instance of Derived, and that 'foo' is marked 'final' in
Derived, we can devirtualize the call to Derived::foo().

Differential Revision: https://reviews.llvm.org/D25813

llvm-svn: 284766
2016-10-20 18:44:14 +00:00
Vedant Kumar cdd6da83a6 [ubsan] Drop dependency on a 64-bit arch in a test (NFC)
This should fix:

    http://lab.llvm.org:8011/builders/clang-hexagon-elf/builds/46184

llvm-svn: 284642
2016-10-19 20:53:16 +00:00
Vedant Kumar da25927188 [ubsan] Re-work check lines to try to appease a bot (NFC)
This bot does not produce the IR I expect -- it's missing some
'handler.dynamic_type_cache_miss:' labels. We don't need to rely on
those labels, so get rid of them in hopes of making the bot happy.

    http://bb.pgr.jp/builders/cmake-clang-x86_64-linux/builds/55493

llvm-svn: 284639
2016-10-19 20:28:35 +00:00
Vedant Kumar 018f266bbc [ubsan] Use the object pointer's type info for devirtualized calls
ubsan reports a false positive 'invalid member call' diagnostic on the
following example (PR30478):

  struct Base1 {
    virtual int f1() { return 1; }
  };

  struct Base2 {
    virtual int f1() { return 2; }
  };

  struct Derived2 final : Base1, Base2 {
    int f1() override { return 3; }
  };

  int t1() {
    Derived2 d;
    return static_cast<Base2 *>(&d)->f1();
  }

Adding the "final" attribute to a most-derived class allows clang to
devirtualize member calls into an instance of that class. We should pass
along the type info of the object pointer to avoid the FP. In this case,
that means passing along the type info for 'Derived2' instead of 'Base2'
when checking the dynamic type of static_cast<Base2 *>(&d2).

Differential Revision: https://reviews.llvm.org/D25448

llvm-svn: 284636
2016-10-19 20:21:16 +00:00