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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.
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Added llvm.vector.reduce.fmaximumnum and llvm.vector.reduce.fminimumnum intrinsics, the reduction variants of llvm.maximumnum and llvm.minimumnum.
Added nofreeobj attribute for attributes and returns, which forbids freeing the underlying object (as opposed to only frees through that specific pointer). Renamed !nofree metadata to !nofreeobj, as it has the same semantics.
The following VP intrinsics have been removed:
llvm.vp.select.*llvm.vp.add.*llvm.vp.sub.*llvm.vp.mul.*llvm.vp.ashr.*llvm.vp.lshr.*llvm.vp.shl.*llvm.vp.or.*llvm.vp.and.*llvm.vp.xor.*llvm.vp.abs.*llvm.vp.smax.*llvm.vp.smin.*llvm.vp.umax.*llvm.vp.umin.*llvm.vp.copysign.*llvm.vp.minnum.*llvm.vp.maxnum.*llvm.vp.minimum.*llvm.vp.maximum.*llvm.vp.fadd.*llvm.vp.fsub.*llvm.vp.fmul.*llvm.vp.fdiv.*llvm.vp.frem.*llvm.vp.fneg.*llvm.vp.fabs.*llvm.vp.sqrt.*llvm.vp.fma.*llvm.vp.fmuladd.*llvm.vp.trunc.*llvm.vp.zext.*llvm.vp.sext.*llvm.vp.fptrunc.*llvm.vp.fpext.*llvm.vp.fptoui.*llvm.vp.fptosi.*llvm.vp.uitofp.*llvm.vp.sitofp.*llvm.vp.ptrtoint.*llvm.vp.inttoptr.*llvm.vp.fcmp.*llvm.vp.icmp.*llvm.vp.ceil.*llvm.vp.floor.*llvm.vp.rint.*llvm.vp.nearbyint.*llvm.vp.round.*llvm.vp.roundeven.*llvm.vp.roundtozero.*llvm.vp.lrint.*llvm.vp.llrint.*llvm.vp.bitreverse.*llvm.vp.bswap.*llvm.vp.ctpop.*llvm.vp.ctlz.*llvm.vp.cttz.*llvm.vp.sadd.sat.*llvm.vp.uadd.sat.*llvm.vp.ssub.sat.*llvm.vp.usub.sat.*llvm.vp.fshl.*llvm.vp.fshr.*llvm.vp.is.fpclass.*These intrinsics previously only set masked-off lanes to poison, and will be automatically upgraded to their non-VP equivalent. On RISC-V the VL optimizer should automatically infer vl in most cases from a store or reduction instruction, so passing around an explicit EVL operand shouldn't be required. If needed a “root” EVL can be synthesized with llvm.vp.merge, e.g:
%x = add <vscale x 2 x i32> %y, %z %res = call <vscale x 2 x i32> @llvm.vp.merge(<vscale x 2 x i32> %x, <vscale x 2 x i32> poison, <vscale x 2 x i1> splat (i1 true), i32 %evl)
The llvm.vp.merge will be folded away but the %evl will be propagated to the add instruction.
TargetOptions::FloatABIType. The soft float ABI should be controlled by setting the "float-abi" module flag.LLVM_ALL_EXPERIMENTAL_TARGETS to LLVM_ALL_TARGETS. It is now built by default and no longer requires LLVM_EXPERIMENTAL_TARGETS_TO_BUILD.!cond operator short-circuits at the first true condition. Subsequent condition : value pairs, along with their corresponding side effects, are left unresolved.Interprocedural passes no longer rewrite the signature of functions marked optnone, so their argument list, return type, and calling convention are preserved. Interprocedural analysis and transformation of such functions is otherwise unaffected.
The IR Outliner has been removed, due to lack of a maintainer and the presence of correctness issues.
Replaced xnack and sramecc target features with amdgpu.xnack and amdgpu.sramecc module flags.
llvm.amdgcn.make.buffer.rsrc now accepts any integer width for its numRecords argument to account for targets that use 32-bit and 45-bit numRecords widths more accurately. If an integer of the incorrect width is used, it will be zero-extended or truncated as needed.
These intrinsics have been removed in favour of llvm.amdgcn.ballot:
llvm.amdgcn.icmpllvm.amdgcn.fcmpSmcsps and Sscsps conditional stack pointer swap extensions.Zilx (Indexed Integer Load) extension.Smijt and Ssijt interrupt jump table extensions and the Smehv and Ssehv synchronous exception hardware vectoring extensions.Smip and Ssip interrupt handler push/pop extensions.Sspmp, Sspmpen and Smpmpdeleg extensions.@llvm.wasm.memory.copy and @llvm.wasm.memory.fill intrinsics for the WebAssembly memory.copy and memory.fill instructions.GetIndexOfChildWithName and GetChildMemberWithName were incorrectly looking up values in all register sets. This meant that GetIndexOfChildWithName could return an index greater than the size of the set, and that GetChildMemberWithName could return values that were actually in a different set. Both methods are now fixed so that they are limited to the registers within the register set. Scripts using these methods may have to be updated as a result.platform.plugin.windows.disable-debug-heap to false.cas::ObjectStore::getMemoryBuffer() was documented as returning a buffer whose lifetime is independent of the CAS, but the buffer it returns may alias storage the CAS owns and so cannot outlive it. The documentation now matches the behavior, and the new getStandaloneMemoryBuffer() provides a buffer that does stay valid after the ObjectStore is destroyed.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.
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