```{warning} These are in-progress notes for the upcoming LLVM {{env.config.release}} release. Release notes for previous releases can be found on [the Download Page](https://releases.llvm.org/download.html). ```
This document contains the release notes for the LLVM Compiler Infrastructure, release {{env.config.release}}. Here we describe the status of LLVM, including major improvements from the previous release, improvements in various subprojects of LLVM, and some of the current users of the code. All LLVM releases may be downloaded from the LLVM releases web site.
For more information about LLVM, including information about the latest release, please check out the main LLVM web site. If you have questions or comments, the Discourse forums is a good place to ask them.
Note that if you are reading this file from a Git checkout or the main LLVM web page, this document applies to the next release, not the current one. To see the release notes for a specific release, please see the releases page.
The x86_mmx
IR type has been removed. It will be translated to the standard vector type <1 x i64>
in bitcode upgrade.
Renamed llvm.experimental.stepvector
intrinsic to llvm.stepvector
.
Added usub_cond
and usub_sat
operations to atomicrmw
.
Introduced noalias.addrspace
metadata.
Remove the following intrinsics which can be replaced with a bitcast
:
llvm.nvvm.bitcast.f2i
llvm.nvvm.bitcast.i2f
llvm.nvvm.bitcast.d2ll
llvm.nvvm.bitcast.ll2d
Remove the following intrinsics which can be replaced with a funnel-shift:
llvm.nvvm.rotate.b32
llvm.nvvm.rotate.right.b64
llvm.nvvm.rotate.b64
Remove the following intrinsics which can be replaced with an addrspacecast
:
llvm.nvvm.ptr.gen.to.global
llvm.nvvm.ptr.gen.to.shared
llvm.nvvm.ptr.gen.to.constant
llvm.nvvm.ptr.gen.to.local
llvm.nvvm.ptr.global.to.gen
llvm.nvvm.ptr.shared.to.gen
llvm.nvvm.ptr.constant.to.gen
llvm.nvvm.ptr.local.to.gen
Remove the following intrinsics which can be relaced with a load from addrspace(1) with an !invariant.load metadata
llvm.nvvm.ldg.global.i
llvm.nvvm.ldg.global.f
llvm.nvvm.ldg.global.p
Operand bundle values can now be metadata strings.
.balign N, 0
, .p2align N, 0
, .align N, 0
in code sections will now fill the required alignment space with a sequence of 0x0
bytes (the requested fill value) rather than NOPs.
Assembler/disassembler support has been added for Armv9.6-A (2024) architecture extensions.
llvm.amdgcn.flat.atomic.fadd
and llvm.amdgcn.global.atomic.fadd
intrinsics. Users should use the {ref}atomicrmw <i_atomicrmw>
instruction with fadd
and addrspace(0) or addrspace(1) instead..balign N, 0
, .p2align N, 0
, .align N, 0
in code sections will now fill the required alignment space with a sequence of 0x0
bytes (the requested fill value) rather than NOPs.
The default behavior for frame pointers in leaf functions has been updated. When the -fno-omit-frame-pointer
option is specified, FPKeepKindStr
is set to -mframe-pointer=all
, meaning the frame pointer (FP) is now retained in leaf functions by default. To eliminate the frame pointer in leaf functions, you must explicitly use the -momit-leaf-frame-pointer
option.
When using the MOVT
or MOVW
instructions, the Assembler will now check to ensure that any addend that is used is within a 16-bit signed value range. If the addend falls outside of this range, the LLVM backend will emit an error like so Relocation Not In Range
.
ppc64
LLC default cpu is updated from ppc
to ppc64
.generic
to pwr7
..balign N, 0
, .p2align N, 0
, .align N, 0
in code sections will now fill the required alignment space with a sequence of 0x0
bytes (the requested fill value) rather than NOPs.-mcpu=syntacore-scr4/5-rv32/64
-mcpu=sifive-p470
was added.-mcpu=rp2350-hazard3
(32-bit only).Zvbc32e
and Zvkgs
extensions are now supported experimentally.Smctr
, Ssctr
and Svvptc
extensions.-mcpu=syntacore-scr7
was added.Zacas
extension is no longer marked as experimental.Smmpm
, Smnpm
, Ssnpm
, Supm
, and Sspm
pointer masking extensions are no longer marked as experimental.Sha
extension is now supported.The default target CPU, “generic”, now enables the -mnontrapping-fptoint
and -mbulk-memory
flags, which correspond to the Bulk Memory Operations and Non-trapping float-to-int Conversions language features, which are widely implemented in engines.
.balign N, 0x90
, .p2align N, 0x90
, and .align N, 0x90
in code sections now fill the required alignment space with repeating 0x90
bytes, rather than using optimised NOP filling. Optimised NOP filling fills the space with NOP instructions of various widths, not just those that use the 0x90
byte encoding. To use optimised NOP filling in a code section, leave off the “fillval” argument, i.e. .balign N
, .p2align N
or .align N
respectively.
Due to the removal of the x86_mmx
IR type, functions with x86_mmx
arguments or return values will use a different, incompatible, calling convention ABI. Such functions are not generally seen in the wild (Clang never generates them!), so this is not expected to result in real-world compatibility problems.
Support ISA of AVX10.2-256
and AVX10.2-512
.
Supported instructions of MOVRS AND AVX10.2
Supported ISA of SM4(EVEX)
.
Supported ISA of MSR_IMM
.
The following symbols are deleted due to the removal of the x86_mmx
IR type:
LLVMX86_MMXTypeKind
LLVMX86MMXTypeInContext
LLVMX86MMXType
The following functions are added to further support non-null-terminated strings:
LLVMGetNamedFunctionWithLength
LLVMGetNamedGlobalWithLength
The following functions are added to access the LLVMContextRef
associated with LLVMValueRef
and LLVMBuilderRef
objects:
LLVMGetValueContext
LLVMGetBuilderContext
The new pass manager can now be invoked with a custom alias analysis pipeline, using the LLVMPassBuilderOptionsSetAAPipeline
function.
It is now also possible to run the new pass manager on a single function, by calling LLVMRunPassesOnFunction
instead of LLVMRunPasses
.
Support for creating instructions with custom synchronization scopes has been added:
LLVMGetSyncScopeID
to map a synchronization scope name to an ID.LLVMBuildFenceSyncScope
, LLVMBuildAtomicRMWSyncScope
and LLVMBuildAtomicCmpXchgSyncScope
versions of the existing builder functions with an additional synchronization scope ID parameter.LLVMGetAtomicSyncScopeID
and LLVMSetAtomicSyncScopeID
to get and set the synchronization scope of any atomic instruction.LLVMIsAtomic
to check if an instruction is atomic, for use with the above functions. Because of backwards compatibility, LLVMIsAtomicSingleThread
and LLVMSetAtomicSingleThread
continue to work with any instruction type.The LLVMSetPersonalityFn
and LLVMSetInitializer
APIs now support clearing the personality function and initializer respectively by passing a null pointer.
The following functions are added to allow iterating over debug records attached to instructions:
LLVMGetFirstDbgRecord
LLVMGetLastDbgRecord
LLVMGetNextDbgRecord
LLVMGetPreviousDbgRecord
Added LLVMAtomicRMWBinOpUSubCond
and LLVMAtomicRMWBinOpUSubSat
to LLVMAtomicRMWBinOp
enum for AtomicRMW instructions.
LLDB can now read the fpmr
register from AArch64 Linux processes and core files.
Program stdout/stderr redirection will now open the file with O_TRUNC flag, make sure to truncate the file if path already exists.
settings set target.output-path/target.error-path <path/to/file>
A wide variety of additional information is available on the LLVM web page, in particular in the documentation section. The web page also contains versions of the API documentation which is up-to-date with the Git version of the source code. You can access versions of these documents specific to this release by going into the llvm/docs/
directory in the LLVM tree.
If you have any questions or comments about LLVM, please feel free to contact us via the Discourse forums.