Commit Graph

7 Commits

Author SHA1 Message Date
Sanjoy Das 3336f681e3 [Verifier] Add verification for TBAA metadata
Summary:
This change adds some verification in the IR verifier around struct path
TBAA metadata.

Other than some basic sanity checks (e.g. we get constant integers where
we expect constant integers), this checks:

 - That by the time an struct access tuple `(base-type, offset)` is
   "reduced" to a scalar base type, the offset is `0`.  For instance, in
   C++ you can't start from, say `("struct-a", 16)`, and end up with
   `("int", 4)` -- by the time the base type is `"int"`, the offset
   better be zero.  In particular, a variant of this invariant is needed
   for `llvm::getMostGenericTBAA` to be correct.

 - That there are no cycles in a struct path.

 - That struct type nodes have their offsets listed in an ascending
   order.

 - That when generating the struct access path, you eventually reach the
   access type listed in the tbaa tag node.

Reviewers: dexonsmith, chandlerc, reames, mehdi_amini, manmanren

Subscribers: mcrosier, llvm-commits

Differential Revision: https://reviews.llvm.org/D26438

llvm-svn: 289402
2016-12-11 20:07:15 +00:00
Duncan P. N. Exon Smith be7ea19b58 IR: Make metadata typeless in assembly
Now that `Metadata` is typeless, reflect that in the assembly.  These
are the matching assembly changes for the metadata/value split in
r223802.

  - Only use the `metadata` type when referencing metadata from a call
    intrinsic -- i.e., only when it's used as a `Value`.

  - Stop pretending that `ValueAsMetadata` is wrapped in an `MDNode`
    when referencing it from call intrinsics.

So, assembly like this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata !{i32 %v}, metadata !0)
      call void @llvm.foo(metadata !{i32 7}, metadata !0)
      call void @llvm.foo(metadata !1, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{metadata !3}, metadata !0)
      ret void, !bar !2
    }
    !0 = metadata !{metadata !2}
    !1 = metadata !{i32* @global}
    !2 = metadata !{metadata !3}
    !3 = metadata !{}

turns into this:

    define @foo(i32 %v) {
      call void @llvm.foo(metadata i32 %v, metadata !0)
      call void @llvm.foo(metadata i32 7, metadata !0)
      call void @llvm.foo(metadata i32* @global, metadata !0)
      call void @llvm.foo(metadata !3, metadata !0)
      call void @llvm.foo(metadata !{!3}, metadata !0)
      ret void, !bar !2
    }
    !0 = !{!2}
    !1 = !{i32* @global}
    !2 = !{!3}
    !3 = !{}

I wrote an upgrade script that handled almost all of the tests in llvm
and many of the tests in cfe (even handling many `CHECK` lines).  I've
attached it (or will attach it in a moment if you're speedy) to PR21532
to help everyone update their out-of-tree testcases.

This is part of PR21532.

llvm-svn: 224257
2014-12-15 19:07:53 +00:00
Kostya Serebryany 2460c3fc73 [tsan] fix PR18146: sometimes a variable written into vptr could have an integer type (after other optimizations)
llvm-svn: 196507
2013-12-05 15:03:02 +00:00
Kostya Serebryany 08b9cf56be [tsan] fix instrumentation of vector vptr updates (https://code.google.com/p/thread-sanitizer/issues/detail?id=43)
llvm-svn: 196079
2013-12-02 08:07:15 +00:00
Dmitry Vyukov b1ad5720a2 tsan: implement no_sanitize_thread attribute
If a function has no_sanitize_thread attribute,
do not instrument memory accesses in it.

llvm-svn: 192871
2013-10-17 07:20:06 +00:00
Manman Ren 0ed04fc9ab TBAA: handle scalar TBAA format and struct-path aware TBAA format.
Remove the command line argument "struct-path-tbaa" since we should not depend
on command line argument to decide which format the IR file is using. Instead,
we check the first operand of the tbaa tag node, if it is a MDNode, we treat
it as struct-path aware TBAA format, otherwise, we treat it as scalar TBAA
format.

When clang starts to use struct-path aware TBAA format no matter whether
struct-path-tbaa is no, and we can auto-upgrade existing bc files, the support
for scalar TBAA format can be dropped.

Existing testing cases are updated to use the struct-path aware TBAA format.

llvm-svn: 191538
2013-09-27 18:34:27 +00:00
Kostya Serebryany 6f8a776041 [tsan] treat vtable pointer updates in a special way (requires tbaa); fix a bug (forgot to return true after instrumenting); make sure the tsan tests are run
llvm-svn: 153448
2012-03-26 17:35:03 +00:00