Commit Graph

14665 Commits

Author SHA1 Message Date
Itay Bookstein
08ed216000 [IR] Refactor GlobalIFunc to inherit from GlobalObject, Remove GlobalIndirectSymbol
As discussed in:
* https://reviews.llvm.org/D94166
* https://lists.llvm.org/pipermail/llvm-dev/2020-September/145031.html

The GlobalIndirectSymbol class lost most of its meaning in
https://reviews.llvm.org/D109792, which disambiguated getBaseObject
(now getAliaseeObject) between GlobalIFunc and everything else.
In addition, as long as GlobalIFunc is not a GlobalObject and
getAliaseeObject returns GlobalObjects, a GlobalAlias whose aliasee
is a GlobalIFunc cannot currently be modeled properly. Creating
aliases for GlobalIFuncs does happen in the wild (e.g. glibc). In addition,
calling getAliaseeObject on a GlobalIFunc will currently return nullptr,
which is undesirable because it should return the object itself for
non-aliases.

This patch refactors the GlobalIFunc class to inherit directly from
GlobalObject, and removes GlobalIndirectSymbol (while inlining the
relevant parts into GlobalAlias and GlobalIFunc). This allows for
calling getAliaseeObject() on a GlobalIFunc to return the GlobalIFunc
itself, making getAliaseeObject() more consistent and enabling
alias-to-ifunc to be properly modeled in the IR.

I exercised some judgement in the API clients of GlobalIndirectSymbol:
some were 'monomorphized' for GlobalAlias and GlobalIFunc, and
some remained shared (with the type adapted to become GlobalValue).

Reviewed By: MaskRay

Differential Revision: https://reviews.llvm.org/D108872
2021-10-20 10:29:47 -07:00
Zhi An Ng
e1fb13401e [WebAssembly] Add prototype relaxed float min max instructions
Add relaxed. f32x4.min, f32x4.max, f64x2.min, f64x2.max. These are only
exposed as builtins, and require user opt-in.

Differential Revision: https://reviews.llvm.org/D112146
2021-10-20 09:41:51 -07:00
Arthur Eubanks
063c2f89aa [clang] Add option to disable -clear-ast-before-backend
Some downstream users have plugins that -clear-ast-before-backend may
affect. Add an option to opt out.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D112100
2021-10-19 20:51:48 -07:00
Zhi An Ng
2542bfa43a [WebAssembly] Add prototype relaxed swizzle instructions
Add i8x16 relaxed_swizzle instructions. These are only
exposed as builtins, and require user opt-in.

Differential Revision: https://reviews.llvm.org/D112022
2021-10-19 17:53:04 -07:00
Yuta Saito
1813fde9cc [WebAssembly] Emit clangast in custom section aligned by 4 bytes
Emit __clangast in custom section instead of named data segment
to find it while iterating sections.
This could be avoided if all data segements (the wasm sense) were
represented as their own sections (in the llvm sense).
This can be resolved by https://github.com/WebAssembly/tool-conventions/issues/138

And the on-disk hashtable in clangast needs to be aligned by 4 bytes,
so add paddings in name length field in custom section header.

The length of clangast section name can be represented in 1 byte
by leb128, and possible maximum pads are 3 bytes, so the section
name length won't be invalid in theory.

Fixes https://bugs.llvm.org/show_bug.cgi?id=35928

Differential Revision: https://reviews.llvm.org/D74531
2021-10-19 15:50:08 -07:00
Noah Shutty
e678c51177 [Support][ThinLTO] Move ThinLTO caching to LLVM Support library
We would like to move ThinLTO’s battle-tested file caching mechanism to
the LLVM Support library so that we can use it elsewhere in LLVM.

Patch By: noajshu

Differential Revision: https://reviews.llvm.org/D111371
2021-10-18 18:57:25 -07:00
Petr Hosek
8e46e34d24 Revert "[Support][ThinLTO] Move ThinLTO caching to LLVM Support library"
This reverts commit 92b8cc52bb since
it broke the gold plugin.
2021-10-18 12:24:05 -07:00
Noah Shutty
92b8cc52bb [Support][ThinLTO] Move ThinLTO caching to LLVM Support library
We would like to move ThinLTO’s battle-tested file caching mechanism to
the LLVM Support library so that we can use it elsewhere in LLVM.

Patch By: noajshu

Differential Revision: https://reviews.llvm.org/D111371
2021-10-18 12:08:49 -07:00
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
Kazu Hirata
d245f2e859 [clang] Use llvm::erase_if (NFC) 2021-10-17 13:50:29 -07:00
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
Zhi An Ng
da07942834 [WebAssembly] Add prototype relaxed laneselect instructions
Add i8x16, i16x8, i32x4, i64x2 laneselect instructions. These are only
exposed as builtins, and require user opt-in.
2021-10-15 17:45:09 -07:00
Kazu Hirata
6a154e606e [clang] Use llvm::is_contained (NFC) 2021-10-15 10:07:08 -07:00
Richard Smith
effbf0bdd0 PR52183: Don't emit code for a void-typed constant expression.
This is unnecessary in general, and wrong when the expression invokes a
consteval function.
2021-10-14 20:55:51 -07:00
Arthur Eubanks
d0a5f61c4f [clang] Support -clear-ast-before-backend without -disable-free
Previously without -disable-free, -clear-ast-before-backend would crash in ~ASTContext() due to various reasons.
This works around that by doing a lot of the cleanup ahead of the destructor so that the destructor doesn't actually do any manual cleanup if we've already cleaned up beforehand.

This actually does save a measurable amount of memory with -clear-ast-before-backend, although at an almost unnoticeable runtime cost:
https://llvm-compile-time-tracker.com/compare.php?from=5d755b32f2775b9219f6d6e2feda5e1417dc993b&to=58ef1c7ad7e2ad45f9c97597905a8cf05a26258c&stat=max-rss

Previously we weren't doing any cleanup with -disable-free, so I tried measuring the impact of always doing the cleanup and didn't measure anything noticeable on llvm-compile-time-tracker.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D111767
2021-10-14 13:43:53 -07:00
Aaron Ballman
68157fe15b Fix a crash on valid consteval code.
Not all constants are emitted within the context of a function, so use
the module's ASTContext instead because 1) that's the same as the
current function ASTContext, and 2) the module can never be null.

Fixes PR50787.
2021-10-14 15:48:10 -04:00
Mike Rice
fb4c451001 [OPENMP51]Initial parsing/sema for adjust_args clause for 'declare variant'
Adds initial parsing and sema for the 'adjust_args' clause.

Note that an AST clause is not created as it instead adds its expressions
to the OMPDeclareVariantAttr.

Differential Revision: https://reviews.llvm.org/D99905
2021-10-13 09:34:09 -07:00
Hsiangkai Wang
5158cfef8b [RISCV] After reverting _mt builtins, add ta argument for LLVM IR.
Previous patch only reverts C builtins for tail policy. In order to keep
LLVM IR intact, add the `ta` argument in vector builtins.
2021-10-13 19:41:49 +08:00
Hsiangkai Wang
ff3ed78304 Revert "[RISCV] Define _m intrinsics as builtins, instead of macros."
This reverts commit 97f0c63783.

As discussed in https://reviews.llvm.org/D110684, it increased the
compile time and the binary size of clang more than 1%. I reverted
this patch first to think about a better way to do it.
2021-10-13 12:21:51 +08:00
Arthur Eubanks
b6a8c69554 [NFC] Rename EmitAssemblyHelper new/legacy PM methods
To reflect the fact that the new PM is the default now.

Differential Revision: https://reviews.llvm.org/D111680
2021-10-12 15:41:44 -07:00
Arthur Eubanks
2cadef6537 [clang] Teardown new PM data structures before running codegen pipeline
Do this by refactoring the optimization and codegen pipelines into separate functions.

This saves a tiny bit of memory in non-LTO builds [1].

[1] https://llvm-compile-time-tracker.com/compare.php?from=fbddf22ef72d3c2e9b14e1501841b03380eef12b&to=cd276df52eb6f2b84a8e1efe5318460c6debf82d&stat=max-rss

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D111582
2021-10-12 14:17:11 -07:00
Kazu Hirata
57b40b5f34 [AST, CodeGen, Driver] Use llvm::is_contained (NFC) 2021-10-12 09:19:49 -07:00
Nathan Sidwell
dcd74716f9 [clang] p0388 conversion to incomplete array
This implements the new implicit conversion sequence to an incomplete
(unbounded) array type.  It is mostly Richard Smith's work, updated to
trunk, testcases added and a few bugs fixed found in such testing.

It is not a complete implementation of p0388.

Differential Revision: https://reviews.llvm.org/D102645
2021-10-12 07:35:20 -07:00
Yonghong Song
a162b67c98 [Clang][Attr] rename btf_tag to btf_decl_tag
Current btf_tag is applied to declaration only.
Per discussion in https://reviews.llvm.org/D111199,
we plan to introduce btf_type_tag attribute for types.
So rename btf_tag to btf_decl_tag to make it easily
differentiable from btf_type_tag.

Differential Revision: https://reviews.llvm.org/D111588
2021-10-11 22:17:17 -07:00
hsmahesha
db9c2d7751 [CFE][Codegen] Remove CodeGenFunction::InitTempAlloca()
Sequel patch to https://reviews.llvm.org/D111316

Finally, remove the defintion of CodeGenFunction::InitTempAlloca().

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D111324
2021-10-12 10:04:15 +05:30
hsmahesha
f7de6962c8 [CFE][Codegen][In-progress] Remove CodeGenFunction::InitTempAlloca()
Sequel patch to https://reviews.llvm.org/D111293.

Remove call to CodeGenFunction::InitTempAlloca() from OpenMP related
codegen part.

Also remove the metadata `!llvm.access.group` from the updated lit
tests.

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D111316
2021-10-12 10:01:46 +05:30
Hsiangkai Wang
97f0c63783 [RISCV] Define _m intrinsics as builtins, instead of macros.
In the original design, we levarage _mt intrinsics to define macros for
_m intrinsics. Such as,

```
__builtin_rvv_vadd_vv_i8m1_mt((vbool8_t)(op0), (vint8m1_t)(op1), (vint8m1_t)(op2), (vint8m1_t)(op3), (size_t)(op4), (size_t)VE_TAIL_AGNOSTIC)
```

However, we could not define generic interface for mask intrinsics any
more due to clang_builtin_alias only accepts clang builtins as its
argument.

In the example,

```
 __rvv_overloaded
 __attribute__((clang_builtin_alias(__builtin_rvv_vadd_vv_i8m1_mt)))
  vint8m1_t vadd(vbool8_t op0, vint8m1_t op1, vint8m1_t op2, vint8m1_t
  op3, size_t op4, size_t op5);
```

op5 is the tail policy argument. When users want to use vadd generic
interface for masked vector add, they need to specify tail policy in the
previous design. In this patch, we define _m intrinsics as clang
builtins to solve the problem.

Differential Revision: https://reviews.llvm.org/D110684
2021-10-12 10:47:55 +08:00
Chris Bieneman
121b2252de AddGlobalAnnotations for function with or without function body.
When AnnotateAttr is on a function, AddGlobalAnnotations is only called
in CodeGenModule::EmitGlobalFunctionDefinition which means AnnotateAttr
on function declaration without function body will be ignored.
The patch will move AddGlobalAnnotations  to
CodeGenModule::SetFunctionAttributes, so with or without function body,
the AnnotateAttr will get code gen for a function.

It'll help case when AnnotateAttr is on external function, and the
AnnotateAttr will be consumed in IR level.

For example, a pass to collect num of uses for functions with
__attribute((annotate("count_use"))) after optimizations,
As long as there's __attribute((annotate("count_use"))), function with
or without function body should be counted.

Reviewed By: aaron.ballman

Differential Revision: https://reviews.llvm.org/D111109

Patch by:  python3kgae (Xiang Li)
2021-10-11 14:50:34 -05:00
hsmahesha
0481682996 [CFE][Codegen][In-progress] Remove CodeGenFunction::InitTempAlloca()
CodeGenFunction::InitTempAlloca() inits the static alloca within the
entry block which may *not* necessarily be correct always.

For example, the current instruction insertion point (pointed by the
instruction builder) could be a program point which is hit multiple
times during the program execution, and it is expected that the static
alloca is initialized every time the program point is hit.

Hence remove CodeGenFunction::InitTempAlloca(), and initialize the
static alloca where the instruction insertion point is at the moment.

This patch, as a starting attempt, removes the calls to
CodeGenFunction::InitTempAlloca() which do not have any side effect on
the lit tests.

Reviewed By: rjmccall

Differential Revision: https://reviews.llvm.org/D111293
2021-10-09 09:23:14 +05:30
Richard Smith
7eae8c6e62 Don't update the vptr at the start of the destructor of a final class.
In this case, we know statically that we're destroying the most-derived
class, so the vptr must already point to the current class and never
needs to be updated.
2021-10-08 19:59:42 -07:00
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
Joseph Huber
bad44d5f39 [OpenMP] Add RTL function for getting number of threads in block.
This patch adds support for the
`__kmpc_get_hardware_num_threads_in_block` function that returns the
number of threads. This was missing in the new runtime and was used by
the AMDGPU plugin which prevented it from using the new runtime. This
patchs also unified the interface for getting the thread numbers in the
frontend.

Originally authored by jdoerfert.

Reviewed By: JonChesterfield

Differential Revision: https://reviews.llvm.org/D111475
2021-10-08 22:21:59 -04:00
Richard Smith
222305d6ff PR51079: Treat thread_local variables with an incomplete class type as
being not trivially destructible when determining if we can skip calling
their thread wrapper function.
2021-10-08 18:46:01 -07:00
Reid Kleckner
89b57061f7 Move TargetRegistry.(h|cpp) from Support to MC
This moves the registry higher in the LLVM library dependency stack.
Every client of the target registry needs to link against MC anyway to
actually use the target, so we might as well move this out of Support.

This allows us to ensure that Support doesn't have includes from MC/*.

Differential Revision: https://reviews.llvm.org/D111454
2021-10-08 14:51:48 -07:00
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
Keith Smiley
68e49aea9a Revert "[clang] Fix absolute file paths with -fdebug-prefix-map"
This reverts commit a23a596793.

This broke a windows test https://buildkite.com/llvm-project/premerge-checks/builds/59492#7dad207c-6cbe-40ad-95e4-c48b47fe2527

Differential Revision: https://reviews.llvm.org/D111444
2021-10-08 10:39:44 -07:00
Keith Smiley
a23a596793 [clang] Fix absolute file paths with -fdebug-prefix-map
Previously if you passed an absolute path to clang, where only part of
the path to the file was remapped, it would result in the file's DIFile
being stored with a duplicate path, for example:

```
!DIFile(filename: "./ios/Sources/bar.c", directory: "./ios/Sources")
```

This change handles absolute paths, specifically in the case they are
remapped to something relative, and uses the dirname for the directory,
and basename for the filename.

This also adds a test verifying this behavior for more standard uses as
well.

Differential Revision: https://reviews.llvm.org/D111352
2021-10-08 10:35:17 -07:00
John McCall
5ab6ee7599 Fix a variety of bugs with nil-receiver checks when targeting
non-Darwin ObjC runtimes:

- Use the same logic the Darwin runtime does for inferring that a
  receiver is non-null and therefore doesn't require null checks.
  Previously we weren't skipping these for non-super dispatch.

- Emit a null check when there's a consumed parameter so that we can
  destroy the argument if the call doesn't happen.  This mostly
  involves extracting some common logic from the Darwin-runtime code.

- Generate a zero aggregate by zeroing the same memory that was used
  in the method call instead of zeroing separate memory and then
  merging them with a phi.  This uses less memory and avoids unnecessary
  copies.

- Emit zero initialization, and generate zero values in phis, using
  the proper zero-value routines instead of assuming that the zero
  value of the result type has a bitwise-zero representation.
2021-10-08 05:44:06 -04:00
Wang, Pengfei
c0f9c7c015 [X86] Check if struct is blank before getting the inner types
This fixes pr52011.

Reviewed By: LuoYuanke

Differential Revision: https://reviews.llvm.org/D111037
2021-10-08 17:09:34 +08:00
Joseph Huber
9efdca87c7 [OpenMP] Introduce new flags to assert thread and team usage in the runtime
This patch adds two flags to be supported for the new runtime. The flags
are `-fopenmp-assume-threads-oversubscription` and
-fopenmp-assume-teams-oversubscription`. These add global values that
can be checked by the work sharing runtime functions to make better
judgements about how to distribute work between the threads.

Reviewed By: jdoerfert

Differential Revision: https://reviews.llvm.org/D111348
2021-10-07 22:23:09 -04:00
Itay Bookstein
40ec1c0f16 [IR][NFC] Rename getBaseObject to getAliaseeObject
To better reflect the meaning of the now-disambiguated {GlobalValue,
GlobalAlias}::getBaseObject after breaking off GlobalIFunc::getResolverFunction
(D109792), the function is renamed to getAliaseeObject.
2021-10-06 19:33:10 -07:00
David Blaikie
f6a561c4d6 DebugInfo: Use clang's preferred names for integer types
This reverts c7f16ab3e3 / r109694 - which
suggested this was done to improve consistency with the gdb test suite.
Possible that at the time GCC did not canonicalize integer types, and so
matching types was important for cross-compiler validity, or that it was
only a case of over-constrained test cases that printed out/tested the
exact names of integer types.

In any case neither issue seems to exist today based on my limited
testing - both gdb and lldb canonicalize integer types (in a way that
happens to match Clang's preferred naming, incidentally) and so never
print the original text name produced in the DWARF by GCC or Clang.

This canonicalization appears to be in `integer_types_same_name_p` for
GDB and in `TypeSystemClang::GetBasicTypeEnumeration` for lldb.

(I tested this with one translation unit defining 3 variables - `long`,
`long (*)()`, and `int (*)()`, and another translation unit that had
main, and a function that took `long (*)()` as a parameter - then
compiled them with mismatched compilers (either GCC+Clang, or
Clang+(Clang with this patch applied)) and no matter the combination,
despite the debug info for one CU naming the type "long int" and the
other naming it "long", both debuggers printed out the name as "long"
and were able to correctly perform overload resolution and pass the
`long int (*)()` variable to the `long (*)()` function parameter)

Did find one hiccup, identified by the lldb test suite - that CodeView
was relying on these names to map them to builtin types in that format.
So added some handling for that in LLVM. (these could be split out into
separate patches, but seems small enough to not warrant it - will do
that if there ends up needing any reverti/revisiting)

Differential Revision: https://reviews.llvm.org/D110455
2021-10-06 16:02:34 -07:00
Jennifer Yu
a4743eba3c Fix assert of "Unable to find base lambda address" from
adjustMemberOfForLambdaCaptures.

The problem is happening when user passes lambda function with reference
type in the map clause.

The natural of the problem when processing generateInfoForCapture,
the BasePointer is generated with new load for a lambda variable with
reference type.  It is not expected in adjustMemberOfForLambdaCaptures.

One way to fix this is to skipping call to generateInfoForCapture for
map(to:lambda).  The map info will be generated later in the call to
generateDefaultMapInfo samiler as firsprivate clase.

This to fix https://bugs.llvm.org/show_bug.cgi?id=52071

Differential Revision:https://reviews.llvm.org/D111115
2021-10-06 14:14:28 -07:00
Arthur Eubanks
6522b7cc32 [clang] Add option to clear AST memory before running LLVM passes
This is to save memory for Clang compiles.
Measuring building PassBuilder.cpp under /usr/bin/time, max rss goes from 0.93GB to 0.7GB.

This does not turn it by default yet.

I've turned on the option locally and run it over a good amount of files without any issues.

For more background, see
https://lists.llvm.org/pipermail/cfe-dev/2021-September/068930.html.

Reviewed By: dblaikie

Differential Revision: https://reviews.llvm.org/D111105
2021-10-06 13:42:22 -07:00
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