Commit Graph

1024 Commits

Author SHA1 Message Date
hyeongyukim b529744c29 [Clang] Rename `disable-noundef-analysis` flag to `-[no-]enable-noundef-analysis`
This flag was previously renamed `enable_noundef_analysis` to
`disable-noundef-analysis,` which is not a conventional name. (Driver and
CC1's boolean options are using [no-] prefix)
As discussed at https://reviews.llvm.org/D105169, this patch reverts its
name to `[no-]enable_noundef_analysis` and enables noundef-analysis as
default.

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D119998
2022-02-18 17:02:41 +09:00
Nikita Popov 5065076698 [CodeGen] Rename deprecated Address constructor
To make uses of the deprecated constructor easier to spot, and to
ensure that no new uses are introduced, rename it to
Address::deprecated().

While doing the rename, I've filled in element types in cases
where it was relatively obvious, but we're still left with 135
calls to the deprecated constructor.
2022-02-17 11:26:42 +01:00
Nikita Popov f208644ed3 [CGBuilder] Remove CreateBitCast() method
Use CreateElementBitCast() instead, or don't work on Address
where not necessary.
2022-02-14 15:06:04 +01:00
Bill Wendling deaf22bc0e [X86] Implement -fzero-call-used-regs option
The "-fzero-call-used-regs" option tells the compiler to zero out
certain registers before the function returns. It's also available as a
function attribute: zero_call_used_regs.

The two upper categories are:

  - "used": Zero out used registers.
  - "all": Zero out all registers, whether used or not.

The individual options are:

  - "skip": Don't zero out any registers. This is the default.
  - "used": Zero out all used registers.
  - "used-arg": Zero out used registers that are used for arguments.
  - "used-gpr": Zero out used registers that are GPRs.
  - "used-gpr-arg": Zero out used GPRs that are used as arguments.
  - "all": Zero out all registers.
  - "all-arg": Zero out all registers used for arguments.
  - "all-gpr": Zero out all GPRs.
  - "all-gpr-arg": Zero out all GPRs used for arguments.

This is used to help mitigate Return-Oriented Programming exploits.

Reviewed By: nickdesaulniers

Differential Revision: https://reviews.llvm.org/D110869
2022-02-08 17:42:54 -08:00
Nikita Popov 18834dca2d [OpenCL] Mark kernel arguments as ABI aligned
Following the discussion on D118229, this marks all pointer-typed
kernel arguments as having ABI alignment, per section 6.3.5 of
the OpenCL spec:

> For arguments to a __kernel function declared to be a pointer to
> a data type, the OpenCL compiler can assume that the pointee is
> always appropriately aligned as required by the data type.

Differential Revision: https://reviews.llvm.org/D118894
2022-02-08 16:12:51 +01:00
Arthur Eubanks 45084eab5e [clang] Fix some clang->llvm type cache invalidation issues
Take the following as an example

  struct z {
    z (*p)();
  };

  z f();

When we attempt to get the LLVM type of f, we recurse into z. z itself
has a function pointer with the same type as f. Given the recursion,
Clang simply treats z::p as a pointer to an empty struct `{}*`. The
LLVM type of f is as expected. So we have two different potential
LLVM types for a given Clang type. If we store one of those into the
cache, when we access the cache with a different context (e.g. we
are/aren't recursing on z) we may get an incorrect result. There is some
attempt to clear the cache in these cases, but it doesn't seem to handle
all cases.

This change makes it so we only use the cache when we are not in any
sort of function context, i.e. `noRecordsBeingLaidOut() &&
FunctionsBeingProcessed.empty()`, which are the cases where we may
decide to choose a different LLVM type for a given Clang type. LLVM
types for builtin types are never recursive so they're always ok.

This allows us to clear the type cache less often (as seen with the
removal of one of the calls to `TypeCache.clear()`). We
still need to clear it when we use a placeholder type then replace it
later with the final type and other dependent types need to be
recalculated.

I've added a check that the cached type matches what we compute. It
triggered in this test case without the fix. It's currently not
check-clang clean so it's not on by default for something like expensive
checks builds.

This change uncovered another issue where the LLVM types for an argument
and its local temporary don't match. For example in type-cache-3, when
expanding z::dc's argument into a temporary alloca, we ConvertType() the
type of z::p which is `void ({}*)*`, which doesn't match the alloca GEP
type of `{}*`.

No noticeable compile time changes:
https://llvm-compile-time-tracker.com/compare.php?from=3918dd6b8acf8c5886b9921138312d1c638b2937&to=50bdec9836ed40e38ece0657f3058e730adffc4c&stat=instructions

Fixes #53465.

Reviewed By: rnk

Differential Revision: https://reviews.llvm.org/D118744
2022-02-07 18:59:09 -08:00
James Y Knight caa1ebde70 Don't assume that a new cleanup was added to InnermostEHScope.
After fa87fa97fb, this was no longer guaranteed to be the cleanup
just added by this code, if IsEHCleanup got disabled. Instead, use
stable_begin(), which _is_ guaranteed to be the cleanup just added.

This caused a crash when a object that is callee destroyed (e.g. with the MS ABI) was passed in a call from a noexcept function.

Added a test to verify.

Fixes: fa87fa97fb
2022-02-04 23:39:42 -05:00
Nikita Popov aa97bc116d [NFC] Remove uses of PointerType::getElementType()
Instead use either Type::getPointerElementType() or
Type::getNonOpaquePointerElementType().

This is part of D117885, in preparation for deprecating the API.
2022-01-25 09:44:52 +01:00
Florian Hahn 67aa314bce
[IRGen] Do not overwrite existing attributes in CGCall.
When adding new attributes, existing attributes are dropped. While
this appears to be a longstanding issue, this was highlighted by D105169
which dropped a lot of attributes due to adding the new noundef
attribute.

Ahmed Bougacha (@ab) tracked down the issue and provided the fix in
CGCall.cpp. I bundled it up and updated the tests.
2022-01-20 13:45:19 +00:00
hyeongyu kim 1b1c8d83d3 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2022-01-16 18:54:17 +09:00
Kevin Athey a141e47138 [NFC] Minimize noundef analysis when disabled
Minor adjustment in order of noundef analysis to be a bit more optimal (when disabled).

Reviewed By: vitalybuka

Differential Revision: https://reviews.llvm.org/D117078
2022-01-12 17:21:19 -08:00
Serge Guelton d2cc6c2d0c Use a sorted array instead of a map to store AttrBuilder string attributes
Using and std::map<SmallString, SmallString> for target dependent attributes is
inefficient: it makes its constructor slightly heavier, and involves extra
allocation for each new string attribute. Storing the attribute key/value as
strings implies extra allocation/copy step.

Use a sorted vector instead. Given the low number of attributes generally
involved, this is cheaper, as showcased by

https://llvm-compile-time-tracker.com/compare.php?from=5de322295f4ade692dc4f1823ae4450ad3c48af2&to=05bc480bf641a9e3b466619af43a2d123ee3f71d&stat=instructions

Differential Revision: https://reviews.llvm.org/D116599
2022-01-10 14:49:53 +01:00
Nikita Popov 53f0538181 [CodeGen] Use correct element type for store to sret
sret is special in that it does not use the memory type
representation. Manually construct the LValue using ConvertType
instead of ConvertTypeForMem here.

This fixes matrix-lowering-opt-levels.c on s390x.
2021-12-23 13:02:49 +01:00
Sanjay Patel 1965cc4695 [CodeGen] remove creation of FP cast function attribute
This is the last cleanup step resulting from D115804 .
Now that clang uses intrinsics when we're in the special FP mode,
we don't need a function attribute as an indicator to the backend.
The LLVM part of the change is in D115885.

Differential Revision: https://reviews.llvm.org/D115886
2021-12-19 11:55:00 -05:00
Kazu Hirata 713ee230f8 [clang] Use llvm::reverse (NFC) 2021-12-17 16:51:42 -08:00
Nikita Popov 9bf917394e [CodeGen] Avoid more pointer element type accesses 2021-12-17 12:11:50 +01:00
Nikita Popov 2d89382b5a [CodeGen] Avoid more pointer element type accesses
This is enough to build sqlite3 with opaque pointers.
2021-12-16 16:34:09 +01:00
Nikita Popov 58c8c53263 [CodeGen] Avoid more pointer element type accesses 2021-12-16 15:26:21 +01:00
Nikita Popov b9492ec649 [CodeGen] Avoid some pointer element type accesses 2021-12-15 14:46:10 +01:00
Nikita Popov b8d121eb1d [CodeGen] Require use of Address::invalid() for invalid address (NFC)
This no longer allows creating an invalid Address through the regular
constructor. There were only two places that did this (AggValueSlot
and EHCleanupScope) which did this by converting a potential nullptr
into an Address. I've fixed both of these by directly storing an
Address instead.

This is intended as a bit of preliminary cleanup for D103465.

Differential Revision: https://reviews.llvm.org/D115630
2021-12-14 12:06:05 +01:00
Aaron Ballman 6c75ab5f66 Introduce _BitInt, deprecate _ExtInt
WG14 adopted the _ExtInt feature from Clang for C23, but renamed the
type to be _BitInt. This patch does the vast majority of the work to
rename _ExtInt to _BitInt, which accounts for most of its size. The new
type is exposed in older C modes and all C++ modes as a conforming
extension. However, there are functional changes worth calling out:

* Deprecates _ExtInt with a fix-it to help users migrate to _BitInt.
* Updates the mangling for the type.
* Updates the documentation and adds a release note to warn users what
is going on.
* Adds new diagnostics for use of _BitInt to call out when it's used as
a Clang extension or as a pre-C23 compatibility concern.
* Adds new tests for the new diagnostic behaviors.

I want to call out the ABI break specifically. We do not believe that
this break will cause a significant imposition for early adopters of
the feature, and so this is being done as a full break. If it turns out
there are critical uses where recompilation is not an option for some
reason, we can consider using ABI tags to ease the transition.
2021-12-06 12:52:01 -05:00
Joseph Huber 4b5c3e591d [OpenMP] Remove doing assumption propagation in the front end.
This patch removes the assumption propagation that was added in D110655
primarily to get assumption informatino on opaque call sites for
optimizations. The analysis done in D111445 allows us to do this more
intelligently in the back-end.

Depends on D111445

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D111463
2021-11-09 17:39:24 -05:00
hyeongyu kim fd9b099906 Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit aacfbb953e.

Revert "Fix lit test failures in CodeGenCoroutines"

This reverts commit 63fff0f5bf.
2021-11-09 02:15:55 +09:00
hyeongyukim aacfbb953e [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169

[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default (2)

This patch updates test files after D105169.
Autogenerated test codes are changed by `utils/update_cc_test_checks.py,` and non-autogenerated test codes are changed as follows:

(1) I wrote a python script that (partially) updates the tests using regex: {F18594904} The script is not perfect, but I believe it gives hints about which patterns are updated to have `noundef` attached.

(2) The remaining tests are updated manually.

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D108453

Resolve lit failures in clang after 8ca4b3e's land

Fix lit test failures in clang-ppc* and clang-x64-windows-msvc

Fix missing failures in clang-ppc64be* and retry fixing clang-x64-windows-msvc

Fix internal_clone(aarch64) inline assembly
2021-11-06 19:19:22 +09:00
Juneyoung Lee 89ad2822af Revert "[Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default"
This reverts commit 7584ef766a.
2021-11-06 15:39:19 +09:00
Juneyoung Lee 7584ef766a [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2021-11-06 15:36:42 +09:00
Juneyoung Lee f193bcc701 Revert D105169 due to the two-stage failure in ASAN
This reverts the following commits:
37ca7a795b
9aa6c72b92
705387c507
8ca4b3ef19
80dba72a66
2021-10-18 23:52:46 +09:00
Juneyoung Lee 80dba72a66 [Clang/Test]: Rename enable_noundef_analysis to disable-noundef-analysis and turn it off by default
Turning on `enable_noundef_analysis` flag allows better codegen by removing freeze instructions.
I modified clang by renaming `enable_noundef_analysis` flag to `disable-noundef-analysis` and turning it off by default.

Test updates are made as a separate patch: D108453

Reviewed By: eugenis

Differential Revision: https://reviews.llvm.org/D105169
2021-10-16 12:01:37 +09:00
Qiu Chaofan 8a714722e2 [NFC] [Clang] Use global enum for explicit float mode
Currently, there're multiple float types that can be represented by
__attribute__((mode(xx))). It's parsed, and then a corresponding type is
created if available.

This refactor moves the enum for mode into a global enum class visible
to ASTContext.

Reviewed By: aaron.ballman, erichkeane

Differential Revision: https://reviews.llvm.org/D111391
2021-10-09 10:39:10 +08:00
Arthur Eubanks a6891d2104 [clang] Set max allowed alignment to 2^32
Followup to D110451 which set LLVM's max allowed alignment to 2^32.

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D111250
2021-10-08 11:44:15 -07:00
Masoud Ataei b0f68791f0 [clang] Option control afn flag
Clang option to set/unset afn fast-math flag.

 Differential: https://reviews.llvm.org/D106191
 Reviewd with: aaron.ballman, erichkeane, and others
2021-10-08 14:26:14 -04:00
Arthur Eubanks 05392466f0 Reland [IR] Increase max alignment to 4GB
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.

This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.

The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.

Updating clang's max allowed alignment will come in a future patch.

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D110451
2021-10-06 13:29:23 -07:00
Arthur Eubanks 569346f274 Revert "Reland [IR] Increase max alignment to 4GB"
This reverts commit 8d64314ffe.
2021-10-06 11:38:11 -07:00
Arthur Eubanks 8d64314ffe Reland [IR] Increase max alignment to 4GB
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.

This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.

The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.

Updating clang's max allowed alignment will come in a future patch.

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D110451
2021-10-06 11:03:51 -07:00
Arthur Eubanks 72cf8b6044 Revert "[IR] Increase max alignment to 4GB"
This reverts commit df84c1fe78.

Breaks some bots
2021-10-06 10:21:35 -07:00
Arthur Eubanks df84c1fe78 [IR] Increase max alignment to 4GB
Currently the max alignment representable is 1GB, see D108661.
Setting the align of an object to 4GB is desirable in some cases to make sure the lower 32 bits are clear which can be used for some optimizations, e.g. https://crbug.com/1016945.

This uses an extra bit in instructions that carry an alignment. We can store 15 bits of "free" information, and with this change some instructions (e.g. AtomicCmpXchgInst) use 14 bits.
We can increase the max alignment representable above 4GB (up to 2^62) since we're only using 33 of the 64 values, but I've just limited it to 4GB for now.

The one place we have to update the bitcode format is for the alloca instruction. It stores its alignment into 5 bits of a 32 bit bitfield. I've added another field which is 8 bits and should be future proof for a while. For backward compatibility, we check if the old field has a value and use that, otherwise use the new field.

Updating clang's max allowed alignment will come in a future patch.

Reviewed By: hans

Differential Revision: https://reviews.llvm.org/D110451
2021-10-06 09:54:14 -07:00
Joseph Huber d12502a3ab [OpenMP] Apply OpenMP assumptions to applicable call sites
This patch adds OpenMP assumption attributes to call sites in applicable
regions. Currently this applies the caller's assumption attributes to
any calls contained within it. So, if a call occurs inside an OpenMP
assumes region to a function outside that region, we will assume that
call respects the assumptions. This is primarily useful for inline
assembly calls used heavily in the OpenMP GPU device runtime, which
allows us to then make judgements about what the ASM will do.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D110655
2021-09-29 16:08:21 -04:00
Roman Lebedev 85ba583eba
[NFCI][clang] Move allocation alignment manifestation for malloc-like into Sema from Codegen
... so that it happens right next to `AddKnownFunctionAttributesForReplaceableGlobalAllocationFunction()`,
which is good for consistency.
2021-09-10 20:49:28 +03:00
Nick Desaulniers 846e562dcc [Clang] add support for error+warning fn attrs
Add support for the GNU C style __attribute__((error(""))) and
__attribute__((warning(""))). These attributes are meant to be put on
declarations of functions whom should not be called.

They are frequently used to provide compile time diagnostics similar to
_Static_assert, but which may rely on non-ICE conditions (ie. relying on
compiler optimizations). This is also similar to diagnose_if function
attribute, but can diagnose after optimizations have been run.

While users may instead simply call undefined functions in such cases to
get a linkage failure from the linker, these provide a much more
ergonomic and actionable diagnostic to users and do so at compile time
rather than at link time. Users instead may be able use inline asm .err
directives.

These are used throughout the Linux kernel in its implementation of
BUILD_BUG and BUILD_BUG_ON macros. These macros generally cannot be
converted to use _Static_assert because many of the parameters are not
ICEs. The Linux kernel still needs to be modified to make use of these
when building with Clang; I have a patch that does so I will send once
this feature is landed.

To do so, we create a new IR level Function attribute, "dontcall" (both
error and warning boil down to one IR Fn Attr).  Then, similar to calls
to inline asm, we attach a !srcloc Metadata node to call sites of such
attributed callees.

The backend diagnoses these during instruction selection, while we still
know that a call is a call (vs say a JMP that's a tail call) in an arch
agnostic manner.

The frontend then reconstructs the SourceLocation from that Metadata,
and determines whether to emit an error or warning based on the callee's
attribute.

Link: https://bugs.llvm.org/show_bug.cgi?id=16428
Link: https://github.com/ClangBuiltLinux/linux/issues/1173

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D106030
2021-08-25 10:34:18 -07:00
Arthur Eubanks 644f88a25b [NFC] addAttribute(FunctionIndex) => addFnAttribute() 2021-08-20 14:18:59 -07:00
Arthur Eubanks 3f4d00bc3b [NFC] More get/removeAttribute() cleanup 2021-08-17 21:05:41 -07:00
Arthur Eubanks de0ae9e89e [NFC] Cleanup more AttributeList::addAttribute() 2021-08-17 21:05:41 -07:00
Arthur Eubanks ad727ab7d9 [NFC] Migrate some callers away from Function/AttributeLists methods that take an index
These methods can be confusing.
2021-08-17 21:05:40 -07:00
Arthur Eubanks 92ce6db9ee [NFC] Rename AttributeList::hasFnAttribute() -> hasFnAttr()
This is more consistent with similar methods.
2021-08-13 11:09:18 -07:00
Arnold Schwaighofer 9eb99d2e73 CodeGen: No need to check for isExternC if HasStrictReturn is already false
NFC intended.

Differential Revision: https://reviews.llvm.org/D107841
2021-08-11 07:42:48 -07:00
Bradley Smith e57e1e4e00 [clang][AArch64][SVE] Avoid going through memory for fixed/scalable predicate casts
For fixed SVE types, predicates are represented using vectors of i8,
where as for scalable types they are represented using vectors of i1. We
can avoid going through memory for casts between these by bitcasting the
i1 scalable vectors to/from a scalable i8 vector of matching size, which
can then use the existing vector insert/extract logic.

Differential Revision: https://reviews.llvm.org/D106860
2021-08-04 16:10:37 +00:00
Varun Gandhi 92dcb1d2db [Clang] Introduce Swift async calling convention.
This change is intended as initial setup. The plan is to add
more semantic checks later. I plan to update the documentation
as more semantic checks are added (instead of documenting the
details up front). Most of the code closely mirrors that for
the Swift calling convention. Three places are marked as
[FIXME: swiftasynccc]; those will be addressed once the
corresponding convention is introduced in LLVM.

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D95561
2021-07-09 11:50:10 -07:00
Nikita Popov a0ea367562 [CodeGen] Avoid nullptr arg to CreateStructGEP (NFC)
For now just make the getPointerElementType() explicit.
2021-07-08 21:21:43 +02:00
Nikita Popov 693251fb2f [CodeGen] Avoid CreateGEP with nullptr type (NFC)
In preparation for dropping support for it. I've replaced it with
a proper type where the correct type was obvious and left an
explicit getPointerElementType() where it wasn't.
2021-07-08 20:38:54 +02:00
Michael Liao 948308ef34 Fix `-Wunused-variable` warning. NFC. 2021-06-28 22:50:36 -04:00