9 Commits

Author SHA1 Message Date
Nikita Popov
532dc62b90 [OpaquePtrs][Clang] Add -no-opaque-pointers to tests (NFC)
This adds -no-opaque-pointers to clang tests whose output will
change when opaque pointers are enabled by default. This is
intended to be part of the migration approach described in
https://discourse.llvm.org/t/enabling-opaque-pointers-by-default/61322/9.

The patch has been produced by replacing %clang_cc1 with
%clang_cc1 -no-opaque-pointers for tests that fail with opaque
pointers enabled. Worth noting that this doesn't cover all tests,
there's a remaining ~40 tests not using %clang_cc1 that will need
a followup change.

Differential Revision: https://reviews.llvm.org/D123115
2022-04-07 12:09:47 +02:00
Leonard Chan
e6f88dc01a [clang][Fuchsia] Turn on relative-vtables by default for Fuchsia
All fuchsia targets will now use the relative-vtables ABI by default.
Also remove -fexperimental-relative-c++-abi-vtables from test RUNs targeting fuchsia.

Differential Revision: https://reviews.llvm.org/D102374
2021-06-01 15:46:09 -07:00
Fangrui Song
d1fd72343c Refactor how -fno-semantic-interposition sets dso_local on default visibility external linkage definitions
The idea is that the CC1 default for ELF should set dso_local on default
visibility external linkage definitions in the default -mrelocation-model pic
mode (-fpic/-fPIC) to match COFF/Mach-O and make output IR similar.

The refactoring is made available by 2820a2ca3a0e69c3f301845420e0067ffff2251b.

Currently only x86 supports local aliases. We move the decision to the driver.
There are three CC1 states:

* -fsemantic-interposition: make some linkages interposable and make default visibility external linkage definitions dso_preemptable.
* (default): selected if the target supports .Lfoo$local: make default visibility external linkage definitions dso_local
* -fhalf-no-semantic-interposition: if neither option is set or the target does not support .Lfoo$local: like -fno-semantic-interposition but local aliases are not used. So references can be interposed if not optimized out.

Add -fhalf-no-semantic-interposition to a few tests using the half-based semantic interposition behavior.
2020-12-31 13:59:45 -08:00
Fangrui Song
fd739804e0 [test] Add {{.*}} to make ELF tests immune to dso_local/dso_preemptable/(none) differences
For a default visibility external linkage definition, dso_local is set for ELF
-fno-pic/-fpie and COFF and Mach-O. Since default clang -cc1 for ELF is similar
to -fpic ("PIC Level" is not set), this nuance causes unneeded binary format differences.

To make emitted IR similar, ELF -cc1 -fpic will default to -fno-semantic-interposition,
which sets dso_local for default visibility external linkage definitions.

To make this flip smooth and enable future (dso_local as definition default),
this patch replaces (function) `define ` with `define{{.*}} `,
(variable/constant/alias) `= ` with `={{.*}} `, or inserts appropriate `{{.*}} `.
2020-12-31 00:27:11 -08:00
Leonard Chan
cf8ff75bad [clang][RelativeVTablesABI] Use dso_local_equivalent rather than emitting stubs
Thanks to D77248, we can bypass the use of stubs altogether and use PLT
relocations if they are available for the target. LLVM and LLD support the
R_AARCH64_PLT32 relocation, so we can also guarantee a static PLT relocation on AArch64.
Not emitting these stubs saves a lot of extra binary size.

Differential Revision: https://reviews.llvm.org/D83812
2020-11-30 16:02:35 -08:00
CJ Johnson
69cd776e1e [CodeGen] Apply 'nonnull' and 'dereferenceable(N)' to 'this' pointer
arguments.

* Adds 'nonnull' and 'dereferenceable(N)' to 'this' pointer arguments
* Gates 'nonnull' on -f(no-)delete-null-pointer-checks
* Introduces this-nonnull.cpp and microsoft-abi-this-nullable.cpp tests to
  explicitly test the behavior of this change
* Refactors hundreds of over-constrained clang tests to permit these
  attributes, where needed
* Updates Clang12 patch notes mentioning this change

Reviewed-by: rsmith, jdoerfert

Differential Revision: https://reviews.llvm.org/D17993
2020-11-16 17:39:17 -08:00
Leonard Chan
71568a9e28 [clang] Frontend components for the relative vtables ABI (round 2)
This patch contains all of the clang changes from D72959.

- Generalize the relative vtables ABI such that it can be used by other targets.
- Add an enum VTableComponentLayout which controls whether components in the
  vtable should be pointers to other structs or relative offsets to those structs.
  Other ABIs can change this enum to restructure how components in the vtable
  are laid out/accessed.
- Add methods to ConstantInitBuilder for inserting relative offsets to a
  specified position in the aggregate being constructed.
- Fix failing tests under new PM and ASan and MSan issues.

See D72959 for background info.

Differential Revision: https://reviews.llvm.org/D77592
2020-06-11 11:17:08 -07:00
Leonard Chan
7201272d4c Revert "[clang] Frontend components for the relative vtables ABI"
This reverts commit 2e009dbcb3e373a59e6e84dce6d51ae8a29f60a5.

Reverting since there were some test failures on buildbots that used the
new pass manager. ASan and MSan are also finding some bugs in this that
I'll need to address.
2020-06-10 13:50:05 -07:00
Leonard Chan
2e009dbcb3 [clang] Frontend components for the relative vtables ABI
This patch contains all of the clang changes from D72959.

- Generalize the relative vtables ABI such that it can be used by other targets.
- Add an enum VTableComponentLayout which controls whether components in the
  vtable should be pointers to other structs or relative offsets to those structs.
  Other ABIs can change this enum to restructure how components in the vtable
  are laid out/accessed.
- Add methods to ConstantInitBuilder for inserting relative offsets to a
  specified position in the aggregate being constructed.

See D72959 for background info.

Differential Revision: https://reviews.llvm.org/D77592
2020-06-10 12:48:10 -07:00