7 Commits

Author SHA1 Message Date
Roman Lebedev
0aef747b84
[NFC][X86][Codegen] Megacommit: mass-regenerate all check lines that were already autogenerated
The motivation is that the update script has at least two deviations
(`<...>@GOT`/`<...>@PLT`/ and not hiding pointer arithmetics) from
what pretty much all the checklines were generated with,
and most of the tests are still not updated, so each time one of the
non-up-to-date tests is updated to see the effect of the code change,
there is a lot of noise. Instead of having to deal with that each
time, let's just deal with everything at once.

This has been done via:
```
cd llvm-project/llvm/test/CodeGen/X86
grep -rl "; NOTE: Assertions have been autogenerated by utils/update_llc_test_checks.py" | xargs -L1 <...>/llvm-project/llvm/utils/update_llc_test_checks.py --llc-binary <...>/llvm-project/build/bin/llc
```

Not all tests were regenerated, however.
2021-06-11 23:57:02 +03:00
Matt Arsenault
2790516418 X86: Use MOV32r0 pseudo instead of directly emitting xor
This was producing reg = xor undef reg, undef reg. This looks similar
to a use of a value to define itself, and I want to disallow undef
uses for SSA virtual registers. If this were to use implicit_def,
there's no guarantee the two operands end up using the same register
(I think no guarantee exists even if the two operands start out as the
same register, but this was violated when I switched this to use an
explicit implicit_def). The MOV32r0 pseudo evidently exists to handle
this case, so use it instead. This was more work than I expected for
the 64-bit case, but I didn't see any helper for materializing a
64-bit 0.
2020-06-29 14:45:20 -04:00
Guozhi Wei
72942459d0 [MBP] Avoid tail duplication if it can't bring benefit
Current tail duplication integrated in bb layout is designed to increase the fallthrough from a BB's predecessor to its successor, but we have observed cases that duplication doesn't increase fallthrough, or it brings too much size overhead.

To overcome these two issues in function canTailDuplicateUnplacedPreds I add two checks:

  make sure there is at least one duplication in current work set.
  the number of duplication should not exceed the number of successors.

The modification in hasBetterLayoutPredecessor fixes a bug that potential predecessor must be at the bottom of a chain.

Differential Revision: https://reviews.llvm.org/D64376
2019-12-06 09:53:53 -08:00
Matthias Braun
da5e7e11d1 SelectionDAGBuilder, mach-o: Skip trap after noreturn call (for Mach-O)
Add NoTrapAfterNoreturn target option which skips emission of traps
behind noreturn calls even if TrapUnreachable is enabled.

Enable the feature on Mach-O to save code size; Comments suggest it is
not possible to enable it for the other users of TrapUnreachable.

rdar://41530228

DifferentialRevision: https://reviews.llvm.org/D48674
llvm-svn: 335877
2018-06-28 17:00:45 +00:00
Alexander Ivchenko
964b27fa21 [X86][CET] Shadow stack fix for setjmp/longjmp
This is the new version of D46181, allowing setjmp/longjmp
to work correctly with the Intel CET shadow stack by storing
SSP on setjmp and fixing it on longjmp. The patch has been
updated to use the cf-protection-return module flag instead
of HasSHSTK, and the bug that caused D46181 to be reverted
has been fixed with the test expanded to track that fix.

patch by mike.dvoretsky

Differential Revision: https://reviews.llvm.org/D47311

llvm-svn: 333990
2018-06-05 09:22:30 +00:00
Jessica Paquette
ec37c640dd Revert "[X86][CET] Shadow stack fix for setjmp/longjmp"
This reverts commit 30962eca38ef02666ebcdded72a94f2cd0292d68.

This commit has been causing test asan failures on a build bot.

http://green.lab.llvm.org/green/job/clang-stage1-configure-RA/45108/

Original commit: https://reviews.llvm.org/D46181

llvm-svn: 331813
2018-05-08 22:00:57 +00:00
Alexander Ivchenko
c47f799289 [X86][CET] Shadow stack fix for setjmp/longjmp
This patch adds a shadow stack fix when compiling
setjmp/longjmp with the shadow stack enabled. This
allows setjmp/longjmp to work correctly with CET.

Patch by mike.dvoretsky

Differential Revision: https://reviews.llvm.org/D46181

llvm-svn: 331748
2018-05-08 09:04:07 +00:00