This reverts commit 178fc4779ece31392a2cd01472b0279e50b3a199.
This attribute was not needed now that we are using the lsan style
ScopedDisabler for disabling this sanitizer
See #106736#106125
For more discussion
After #98505, the textual IR keyword `x86_mmx` was temporarily made to
parse as `<1 x i64>`, so as not to require a lot of test update noise.
This completes the removal of the type, by removing the`x86_mmx` keyword
from the IR parser, and making the (now no-op) test updates via `sed -i
's/\bx86_mmx\b/<1 x i64>/g' $(git grep -l x86_mmx llvm/test/)`.
Resulting bitcasts from <1 x i64> to itself were then manually deleted.
Changes to llvm/test/Bitcode/compatibility-$VERSION.ll were reverted, as
they're intended to be equivalent to the .bc file, if parsed by old
LLVM, so shouldn't be updated.
A few tests were removed, as they're no longer testing anything, in the
following files:
- llvm/test/Transforms/GlobalOpt/x86_mmx_load.ll
- llvm/test/Transforms/InstCombine/cast.ll
- llvm/test/Transforms/InstSimplify/ConstProp/gep-zeroinit-vector.ll
Works towards issue #98272.
It is now translated to `<1 x i64>`, which allows the removal of a bunch
of special casing.
This _incompatibly_ changes the ABI of any LLVM IR function with
`x86_mmx` arguments or returns: instead of passing in mmx registers,
they will now be passed via integer registers. However, the real-world
incompatibility caused by this is expected to be minimal, because Clang
never uses the x86_mmx type -- it lowers `__m64` to either `<1 x i64>`
or `double`, depending on ABI.
This change does _not_ eliminate the SelectionDAG `MVT::x86mmx` type.
That type simply no longer corresponds to an IR type, and is used only
by MMX intrinsics and inline-asm operands.
Because SelectionDAGBuilder only knows how to generate the
operands/results of intrinsics based on the IR type, it thus now
generates the intrinsics with the type MVT::v1i64, instead of
MVT::x86mmx. We need to fix this before the DAG LegalizeTypes, and thus
have the X86 backend fix them up in DAGCombine. (This may be a
short-lived hack, if all the MMX intrinsics can be removed in upcoming
changes.)
Works towards issue #98272.
This defines a new kind of IR Constant that represents a ptrauth signed
pointer, as used in AArch64 PAuth.
It allows representing most kinds of signed pointer constants used thus
far in the llvm ptrauth implementations, notably those used in the
Darwin and ELF ABIs being implemented for c/c++. These signed pointer
constants are then lowered to ELF/MachO relocations.
These can be simply thought of as a constant `llvm.ptrauth.sign`, with
the interesting addition of discriminator computation: the `ptrauth`
constant can also represent a combined blend, when both address and
integer discriminator operands are used. Both operands are otherwise
optional, with default values 0/null.
Currently, the builtins used for implementing `va_list` handling
unconditionally take their arguments as unqualified `ptr`s i.e. pointers
to AS 0. This does not work for targets where the default AS is not 0 or
AS 0 is not a viable AS (for example, a target might choose 0 to
represent the constant address space). This patch changes the builtins'
signature to take generic `anyptr` args, which corrects this issue. It
is noisy due to the number of tests affected. A test for an upstream
target which does not use 0 as its default AS (SPIRV for HIP device
compilations) is added as well.
As part of the migration to ptradd
(https://discourse.llvm.org/t/rfc-replacing-getelementptr-with-ptradd/68699),
we need to change the representation of the `inrange` attribute, which
is used for vtable splitting.
Currently, inrange is specified as follows:
```
getelementptr inbounds ({ [4 x ptr], [4 x ptr] }, ptr @vt, i64 0, inrange i32 1, i64 2)
```
The `inrange` is placed on a GEP index, and all accesses must be "in
range" of that index. The new representation is as follows:
```
getelementptr inbounds inrange(-16, 16) ({ [4 x ptr], [4 x ptr] }, ptr @vt, i64 0, i32 1, i64 2)
```
This specifies which offsets are "in range" of the GEP result. The new
representation will continue working when canonicalizing to ptradd
representation:
```
getelementptr inbounds inrange(-16, 16) (i8, ptr @vt, i64 48)
```
The inrange offsets are relative to the return value of the GEP. An
alternative design could make them relative to the source pointer
instead. The result-relative format was chosen on the off-chance that we
want to extend support to non-constant GEPs in the future, in which case
this variant is more expressive.
This implementation "upgrades" the old inrange representation in bitcode
by simply dropping it. This is a very niche feature, and I don't think
trying to upgrade it is worthwhile. Let me know if you disagree.
The new experimental calling convention preserve_none is the opposite
side of existing preserve_all. It tries to preserve as few general
registers as possible. So all general registers are caller saved
registers. It can also uses more general registers to pass arguments.
This attribute doesn't impact floating-point registers. Floating-point
registers still follow the c calling convention.
Currently preserve_none is supported on X86-64 only. It changes the c
calling convention in following fields:
* RSP and RBP are the only preserved general registers, all other
general registers are caller saved registers.
* We can use [RDI, RSI, RDX, RCX, R8, R9, R11, R12, R13, R14, R15, RAX]
to pass arguments.
It can improve the performance of hot tailcall chain, because many
callee saved registers' save/restore instructions can be removed if the
tail functions are using preserve_none. In my experiment in protocol
buffer, the parsing functions are improved by 3% to 10%.
This flag indicates that every bit is known to be zero in at least one
of the inputs. This allows the Or to be treated as an Add since there is
no possibility of a carry from any bit.
If the flag is present and this property does not hold, the result is
poison.
This makes it easier to reverse the InstCombine transform that turns Add
into Or.
This is inspired by a comment here
https://github.com/llvm/llvm-project/pull/71955#discussion_r1391614578
Discourse thread
https://discourse.llvm.org/t/rfc-add-or-disjoint-flag/75036
The WebKit Calling Convention was created specifically for the WebKit
FTL. FTL
doesn't use LLVM anymore and therefore this calling convention is
obsolete.
This commit removes the WebKit CC, its associated tests, and
documentation.
This allows use with non-0 address space stacks. llvm_ptr_ty should
never be used. This could use some more percolation up through mlir,
but this is enough to fix existing tests.
https://reviews.llvm.org/D156666
This carries a bitmask indicating forbidden floating-point value kinds
in the argument or return value. This will enable interprocedural
-ffinite-math-only optimizations. This is primarily to cover the
no-nans and no-infinities cases, but also covers the other floating
point classes for free. Textually, this provides a number of names
corresponding to bits in FPClassTest, e.g.
call nofpclass(nan inf) @must_be_finite()
call nofpclass(snan) @cannot_be_snan()
This is more expressive than the existing nnan and ninf fast math
flags. As an added bonus, you can represent fun things like nanf:
declare nofpclass(inf zero sub norm) float @only_nans()
Compared to nnan/ninf:
- Can be applied to individual call operands as well as the return value
- Can distinguish signaling and quiet nans
- Distinguishes the sign of infinities
- Can be safely propagated since it doesn't imply anything about
other operands.
- Does not apply to FP instructions; it's not a flag
This is one step closer to being able to retire "no-nans-fp-math" and
"no-infs-fp-math". The one remaining situation where we have no way to
represent no-nans/infs is for loads (if we wanted to solve this we
could introduce !nofpclass metadata, following along with
noundef/!noundef).
This is to help simplify the GPU builtin math library
distribution. Currently the library code has explicit finite math only
checks, read from global constants the compiler driver needs to set
based on the compiler flags during linking. We end up having to
internalize the library into each translation unit in case different
linked modules have different math flags. By propagating known-not-nan
and known-not-infinity information, we can automatically prune the
edge case handling in most functions if the function is only reached
from fast math uses.
These are essentially add/sub 1 with a clamping value.
AMDGPU has instructions for these. CUDA/HIP expose these as
atomicInc/atomicDec. Currently we use target intrinsics for these,
but those do no carry the ordering and syncscope. Add these to
atomicrmw so we can carry these and benefit from the regular
legalization processes.
This switches everything to use the memory attribute proposed in
https://discourse.llvm.org/t/rfc-unify-memory-effect-attributes/65579.
The old argmemonly, inaccessiblememonly and inaccessiblemem_or_argmemonly
attributes are dropped. The readnone, readonly and writeonly attributes
are restricted to parameters only.
The old attributes are auto-upgraded both in bitcode and IR.
The bitcode upgrade is a policy requirement that has to be retained
indefinitely. The IR upgrade is mainly there so it's not necessary
to update all tests using memory attributes in this patch, which
is already large enough. We could drop that part after migrating
tests, or retain it longer term, to make it easier to import IR
from older LLVM versions.
High-level Function/CallBase APIs like doesNotAccessMemory() or
setDoesNotAccessMemory() are mapped transparently to the memory
attribute. Code that directly manipulates attributes (e.g. via
AttributeList) on the other hand needs to switch to working with
the memory attribute instead.
Differential Revision: https://reviews.llvm.org/D135780
For MTE globals, we should have clang emit the attribute for all GV's
that it creates, and then use that in the upcoming AArch64 global
tagging IR pass. We need a positive attribute for this sanitizer (rather
than implicit sanitization of all globals) because it needs to interact
with other parts of LLVM, including:
1. Suppressing certain global optimisations (like merging),
2. Emitting extra directives by the ASM writer, and
3. Putting extra information in the symbol table entries.
While this does technically make the LLVM IR / bitcode format
non-backwards-compatible, nobody should have used this attribute yet,
because it's a no-op.
Reviewed By: eugenis
Differential Revision: https://reviews.llvm.org/D128950
This patch adds the support for `fmax` and `fmin` operations in `atomicrmw`
instruction. For now (at least in this patch), the instruction will be expanded
to CAS loop. There are already a couple of targets supporting the feature. I'll
create another patch(es) to enable them accordingly.
Reviewed By: arsenm
Differential Revision: https://reviews.llvm.org/D127041
Plan is the migrate the global variable metadata for sanitizers, that's
currently carried around generally in the 'llvm.asan.globals' section,
onto the global variable itself.
This patch adds the attribute and plumbs it through the LLVM IR and
bitcode formats, but is a no-op other than that so far.
Reviewed By: vitalybuka, kstoimenov
Differential Revision: https://reviews.llvm.org/D126100
I chose to encode the allockind information in a string constant because
otherwise we would get a bit of an explosion of keywords to deal with
the possible permutations of allocation function types.
I'm not sure that CodeGen.h is the correct place for this enum, but it
seemed to kind of match the UWTableKind enum so I put it in the same
place. Constructive suggestions on a better location most certainly
encouraged.
Differential Revision: https://reviews.llvm.org/D123088
This adds support for pointer types for `atomic xchg` and let us write
instructions such as `atomicrmw xchg i64** %0, i64* %1 seq_cst`. This
is similar to the patch for allowing atomicrmw xchg on floating point
types: https://reviews.llvm.org/D52416.
Differential Revision: https://reviews.llvm.org/D124728
This continues the push away from hard-coded knowledge about functions
towards attributes. We'll use this to annotate free(), realloc() and
cousins and obviate the hard-coded list of free functions.
Differential Revision: https://reviews.llvm.org/D123083
This will let us start moving away from hard-coded attributes in
MemoryBuiltins.cpp and put the knowledge about various attribute
functions in the compilers that emit those calls where it probably
belongs.
Differential Revision: https://reviews.llvm.org/D117921
Currently adding attribute no_sanitize("bounds") isn't disabling
-fsanitize=local-bounds (also enabled in -fsanitize=bounds). The Clang
frontend handles fsanitize=array-bounds which can already be disabled by
no_sanitize("bounds"). However, instrumentation added by the
BoundsChecking pass in the middle-end cannot be disabled by the
attribute.
The fix is very similar to D102772 that added the ability to selectively
disable sanitizer pass on certain functions.
In this patch, if no_sanitize("bounds") is provided, an additional
function attribute (NoSanitizeBounds) is attached to IR to let the
BoundsChecking pass know we want to disable local-bounds checking. In
order to support this feature, the IR is extended (similar to D102772)
to make Clang able to preserve the information and let BoundsChecking
pass know bounds checking is disabled for certain function.
Reviewed By: melver
Differential Revision: https://reviews.llvm.org/D119816
Verify that the resolver exists, that it is a defined
Function, and that its return type matches the ifunc's
type. Add corresponding check to BitcodeReader, change
clang to emit the correct type, and fix tests to comply.
Reviewed By: MaskRay
Differential Revision: https://reviews.llvm.org/D112349
The purpose of __attribute__((disable_sanitizer_instrumentation)) is to
prevent all kinds of sanitizer instrumentation applied to a certain
function, Objective-C method, or global variable.
The no_sanitize(...) attribute drops instrumentation checks, but may
still insert code preventing false positive reports. In some cases
though (e.g. when building Linux kernel with -fsanitize=kernel-memory
or -fsanitize=thread) the users may want to avoid any kind of
instrumentation.
Differential Revision: https://reviews.llvm.org/D108029
In the textual format, `noduplicates` means no COMDAT/section group
deduplication is performed. Therefore, if both sets of sections are retained, and
they happen to define strong external symbols with the same names,
there will be a duplicate definition linker error.
In PE/COFF, the selection kind lowers to `IMAGE_COMDAT_SELECT_NODUPLICATES`.
The name describes the corollary instead of the immediate semantics. The name
can cause confusion to other binary formats (ELF, wasm) which have implemented/
want to implement the "no deduplication" selection kind. Rename it to be clearer.
Reviewed By: rnk
Differential Revision: https://reviews.llvm.org/D106319
We really ought to support no_sanitize("coverage") in line with other
sanitizers. This came up again in discussions on the Linux-kernel
mailing lists, because we currently do workarounds using objtool to
remove coverage instrumentation. Since that support is only on x86, to
continue support coverage instrumentation on other architectures, we
must support selectively disabling coverage instrumentation via function
attributes.
Unfortunately, for SanitizeCoverage, it has not been implemented as a
sanitizer via fsanitize= and associated options in Sanitizers.def, but
rolls its own option fsanitize-coverage. This meant that we never got
"automatic" no_sanitize attribute support.
Implement no_sanitize attribute support by special-casing the string
"coverage" in the NoSanitizeAttr implementation. To keep the feature as
unintrusive to existing IR generation as possible, define a new negative
function attribute NoSanitizeCoverage to propagate the information
through to the instrumentation pass.
Fixes: https://bugs.llvm.org/show_bug.cgi?id=49035
Reviewed By: vitalybuka, morehouse
Differential Revision: https://reviews.llvm.org/D102772
Swift's new concurrency features are going to require guaranteed tail calls so
that they don't consume excessive amounts of stack space. This would normally
mean "tailcc", but there are also Swift-specific ABI desires that don't
naturally go along with "tailcc" so this adds another calling convention that's
the combination of "swiftcc" and "tailcc".
Support is added for AArch64 and X86 for now.
This extends any frame record created in the function to include that
parameter, passed in X22.
The new record looks like [X22, FP, LR] in memory, and FP is stored with 0b0001
in bits 63:60 (CodeGen assumes they are 0b0000 in normal operation). The effect
of this is that tools walking the stack should expect to see one of three
values there:
* 0b0000 => a normal, non-extended record with just [FP, LR]
* 0b0001 => the extended record [X22, FP, LR]
* 0b1111 => kernel space, and a non-extended record.
All other values are currently reserved.
If compiling for arm64e this context pointer is address-discriminated with the
discriminator 0xc31a and the DB (process-specific) key.
There is also an "i8** @llvm.swift.async.context.addr()" intrinsic providing
front-ends access to this slot (and forcing its creation initialized to nullptr
if necessary).
When we pass a AArch64 Homogeneous Floating-Point
Aggregate (HFA) argument with increased alignment
requirements, for example
struct S {
__attribute__ ((__aligned__(16))) double v[4];
};
Clang uses `[4 x double]` for the parameter, which is passed
on the stack at alignment 8, whereas it should be at
alignment 16, following Rule C.4 in
AAPCS (https://github.com/ARM-software/abi-aa/blob/master/aapcs64/aapcs64.rst#642parameter-passing-rules)
Currently we don't have a way to express in LLVM IR the
alignment requirements of the function arguments. The align
attribute is applicable to pointers only, and only for some
special ways of passing arguments (e..g byval). When
implementing AAPCS32/AAPCS64, clang resorts to dubious hacks
of coercing to types, which naturally have the needed
alignment. We don't have enough types to cover all the
cases, though.
This patch introduces a new use of the stackalign attribute
to control stack slot alignment, when and if an argument is
passed in memory.
The attribute align is left as an optimizer hint - it still
applies to pointer types only and pertains to the content of
the pointer, whereas the alignment of the pointer itself is
determined by the stackalign attribute.
For byval arguments, the stackalign attribute assumes the
role, previously perfomed by align, falling back to align if
stackalign` is absent.
On the clang side, when passing arguments using the "direct"
style (cf. `ABIArgInfo::Kind`), now we can optionally
specify an alignment, which is emitted as the new
`stackalign` attribute.
Patch by Momchil Velikov and Lucas Prates.
Differential Revision: https://reviews.llvm.org/D98794
I think byval/sret and the others are close to being able to rip out
the code to support the missing type case. A lot of this code is
shared with inalloca, so catch this up to the others so that can
happen.
This is a follow up patch to D83136 adding the align attribute to `cmpxchg`.
See also D83465 for `atomicrmw`.
Differential Revision: https://reviews.llvm.org/D87443
Currently the backend special cases x86_intrcc and treats the first
parameter as byval. Make the IR require byval for this parameter to
remove this special case, and avoid the dependence on the pointee
element type.
Fixes bug 46672.
I'm not sure the IR is enforcing all the calling convention
constraints. clang seems to ignore the attribute for empty parameter
lists, but the IR tolerates it.
Define ConstantData::PoisonValue.
Add support for poison value to LLLexer/LLParser/BitcodeReader/BitcodeWriter.
Add support for poison value to llvm-c interface.
Add support for poison value to OCaml binding.
Add m_Poison in PatternMatch.
Differential Revision: https://reviews.llvm.org/D71126
