Commit Graph

5 Commits

Author SHA1 Message Date
Yonghong Song 91d5c2a035 [CLANG][BPF] permit any argument type for __builtin_preserve_access_index()
Commit c15aa241f8 ("[CLANG][BPF] change __builtin_preserve_access_index()
signature") changed the builtin function signature to
  PointerT __builtin_preserve_access_index(PointerT ptr)
with a pointer type as the argument/return type, where argument and
return types must be the same.

There is really no reason for this constraint. The builtin just
presented a code region so that IR builtins
  __builtin_{array, struct, union}_preserve_access_index
can be applied.

This patch removed the pointer type restriction to permit any
argument type as long as it is permitted by the compiler.

Differential Revision: https://reviews.llvm.org/D67883

llvm-svn: 372516
2019-09-22 17:33:48 +00:00
Yonghong Song c15aa241f8 [CLANG][BPF] change __builtin_preserve_access_index() signature
The clang intrinsic __builtin_preserve_access_index() currently
has signature:
  const void * __builtin_preserve_access_index(const void * ptr)

This may cause compiler warning when:
  - parameter type is "volatile void *" or "const volatile void *", or
  - the assign-to type of the intrinsic does not have "const" qualifier.
Further, this signature does not allow dereference of the
builtin result pointer as it is a "const void *" type, which
adds extra step for the user to do type casting.

Let us change the signature to:
  PointerT __builtin_preserve_access_index(PointerT ptr)
such that the result and argument types are the same.
With this, directly dereferencing the builtin return value
becomes possible.

Differential Revision: https://reviews.llvm.org/D67734

llvm-svn: 372294
2019-09-19 02:59:43 +00:00
Yonghong Song 4754814c5a fix unnamed fiefield issue and add tests for __builtin_preserve_access_index intrinsic
The original commit is r366076. It is temporarily reverted (r366155)
due to test failure. This resubmit makes test more robust by accepting
regex instead of hardcoded names/references in several places.

This is a followup patch for https://reviews.llvm.org/D61809.
Handle unnamed bitfield properly and add more test cases.

Fixed the unnamed bitfield issue. The unnamed bitfield is ignored
by debug info, so we need to ignore such a struct/union member
when we try to get the member index in the debug info.

D61809 contains two test cases but not enough as it does
not checking generated IRs in the fine grain level, and also
it does not have semantics checking tests.
This patch added unit tests for both code gen and semantics checking for
the new intrinsic.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 366231
2019-07-16 17:24:33 +00:00
Eric Christopher fdcbd5fa48 Temporarily Revert "fix unnamed fiefield issue and add tests for __builtin_preserve_access_index intrinsic"
The commit had tests that would only work with names in the IR.

This reverts commit r366076.

llvm-svn: 366155
2019-07-15 23:49:31 +00:00
Yonghong Song e5086481b6 fix unnamed fiefield issue and add tests for __builtin_preserve_access_index intrinsic
This is a followup patch for https://reviews.llvm.org/D61809.
Handle unnamed bitfield properly and add more test cases.

Fixed the unnamed bitfield issue. The unnamed bitfield is ignored
by debug info, so we need to ignore such a struct/union member
when we try to get the member index in the debug info.

D61809 contains two test cases but not enough as it does
not checking generated IRs in the fine grain level, and also
it does not have semantics checking tests.
This patch added unit tests for both code gen and semantics checking for
the new intrinsic.

Signed-off-by: Yonghong Song <yhs@fb.com>
llvm-svn: 366076
2019-07-15 15:42:41 +00:00