[llvm] [TailRecElim] Handle discarded-call return conflicts with a shift accumulator (PR #221694)

Fri Sep 18 05:11:30 PDT 2026

llvm-ci wrote:

LLVM Buildbot has detected a new failure on builder `profcheck` running on `profcheck-b1` while building `llvm` at step 5 "annotate".

Full details are available at: https://lab.llvm.org/buildbot/#/builders/223/builds/12081

<details>
<summary>Here is the relevant piece of the build log for the reference</summary>

```
Step 5 (annotate) failure: '../llvm-zorg/zorg/buildbot/builders/annotated/profcheck.sh --jobs=64' (failure)
...
PASS: LLVM :: Analysis/BasicAA/noalias-inttoptr.ll (30647 of 46848)
PASS: LLVM :: Analysis/ScalarEvolution/scev-expander-reuse-unroll.ll (30648 of 46848)
PASS: LLVM :: Transforms/SLPVectorizer/sincos.ll (30649 of 46848)
PASS: LLVM :: Transforms/InstCombine/icmp-vec-inseltpoison.ll (30650 of 46848)
PASS: LLVM :: Transforms/InstCombine/stepvector-known-bits.ll (30651 of 46848)
PASS: LLVM :: Transforms/LoopRotate/delete-dbg-values.ll (30652 of 46848)
PASS: LLVM :: Transforms/InstCombine/2007-03-21-SignedRangeTest.ll (30653 of 46848)
PASS: LLVM :: Transforms/DeadStoreElimination/multiblock-captures.ll (30654 of 46848)
PASS: LLVM :: CodeGen/X86/variadic-node-pic.ll (30655 of 46848)
PASS: LLVM :: Transforms/GlobalOpt/new-promote.ll (30656 of 46848)
FAIL: LLVM :: Transforms/TailCallElim/shl-accumulator-opt.ll (30657 of 46848)
PASS: LLVM :: Transforms/LoopFusion/diagnostics_analysis.ll (30658 of 46848)
PASS: LLVM :: Transforms/InstCombine/scalbn-to-ldexp.ll (30659 of 46848)
PASS: LLVM :: CodeGen/X86/2010-06-15-FastAllocEarlyCLobber.ll (30660 of 46848)
PASS: LLVM :: CodeGen/AArch64/tailcall-fastisel.ll (30661 of 46848)
PASS: LLVM :: Transforms/SampleProfile/inline-act.ll (30662 of 46848)
PASS: LLVM :: Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-ne-to-icmp-ugt.ll (30663 of 46848)
PASS: LLVM :: Transforms/LoopSimplify/dbg-loc.ll (30664 of 46848)
PASS: LLVM :: CodeGen/BPF/preserve-static-offset/store-undo-volatile.ll (30665 of 46848)
PASS: LLVM :: DebugInfo/Generic/assignment-tracking/sroa/complex.ll (30666 of 46848)
PASS: LLVM :: Transforms/Coroutines/coro-alloc-with-param-O0.ll (30667 of 46848)
PASS: LLVM :: Transforms/JumpThreading/thread-debug-info.ll (30668 of 46848)
PASS: LLVM :: Transforms/InstCombine/select-icmp-xor.ll (30669 of 46848)
PASS: LLVM :: Transforms/LoopSimplifyCFG/pr39783.ll (30670 of 46848)
PASS: LLVM :: Assembler/2007-03-19-NegValue.ll (30671 of 46848)
PASS: LLVM :: Transforms/SLPVectorizer/X86/pr16628.ll (30672 of 46848)
PASS: LLVM :: CodeGen/DirectX/any.ll (30673 of 46848)
PASS: LLVM :: Transforms/ConstraintElimination/geps-unsigned-predicates.ll (30674 of 46848)
PASS: LLVM :: Transforms/IndVarSimplify/2011-11-17-selfphi.ll (30675 of 46848)
PASS: LLVM :: Transforms/RewriteStatepointsForGC/base-inference.ll (30676 of 46848)
PASS: LLVM :: Analysis/LoopAccessAnalysis/load-store-index-loaded-in-loop.ll (30677 of 46848)
PASS: LLVM :: Transforms/RelLookupTableConverter/X86/opaque-ptr.ll (30678 of 46848)
PASS: LLVM :: Transforms/LICM/explicit_guards.ll (30679 of 46848)
PASS: LLVM :: Transforms/JumpThreading/branch-debug-info.ll (30680 of 46848)
PASS: LLVM :: Transforms/InstCombine/pr38897.ll (30681 of 46848)
PASS: LLVM :: CodeGen/AArch64/phi-dbg.ll (30682 of 46848)
PASS: LLVM :: Transforms/GlobalOpt/sra-many-stores.ll (30683 of 46848)
PASS: LLVM :: CodeGen/VE/Vector/vp_reduce_smax.ll (30684 of 46848)
PASS: LLVM :: Transforms/InstSimplify/ConstProp/basictest.ll (30685 of 46848)
PASS: LLVM :: Transforms/InstSimplify/result-of-usub-is-non-zero-and-no-overflow.ll (30686 of 46848)
PASS: LLVM :: CodeGen/MSP430/2009-11-20-NewNode.ll (30687 of 46848)
PASS: LLVM :: FileCheck/check-literal.txt (30688 of 46848)
PASS: LLVM :: DebugInfo/ARM/move-dbg-values.mir (30689 of 46848)
PASS: LLVM :: Transforms/SpeculativeExecution/spec-casts.ll (30690 of 46848)
PASS: LLVM :: Transforms/NewGVN/crash-no-aa.ll (30691 of 46848)
PASS: LLVM :: CodeGen/SystemZ/tdc-07.ll (30692 of 46848)
PASS: LLVM :: Transforms/InstSimplify/freeze.ll (30693 of 46848)
PASS: LLVM :: CodeGen/Thumb/triple.ll (30694 of 46848)
PASS: LLVM :: Transforms/SimplifyCFG/poison-merge.ll (30695 of 46848)
Step 7 (Ninja) failure: Ninja (failure)
...
PASS: LLVM :: Analysis/BasicAA/noalias-inttoptr.ll (30647 of 46848)
PASS: LLVM :: Analysis/ScalarEvolution/scev-expander-reuse-unroll.ll (30648 of 46848)
PASS: LLVM :: Transforms/SLPVectorizer/sincos.ll (30649 of 46848)
PASS: LLVM :: Transforms/InstCombine/icmp-vec-inseltpoison.ll (30650 of 46848)
PASS: LLVM :: Transforms/InstCombine/stepvector-known-bits.ll (30651 of 46848)
PASS: LLVM :: Transforms/LoopRotate/delete-dbg-values.ll (30652 of 46848)
PASS: LLVM :: Transforms/InstCombine/2007-03-21-SignedRangeTest.ll (30653 of 46848)
PASS: LLVM :: Transforms/DeadStoreElimination/multiblock-captures.ll (30654 of 46848)
PASS: LLVM :: CodeGen/X86/variadic-node-pic.ll (30655 of 46848)
PASS: LLVM :: Transforms/GlobalOpt/new-promote.ll (30656 of 46848)
FAIL: LLVM :: Transforms/TailCallElim/shl-accumulator-opt.ll (30657 of 46848)
PASS: LLVM :: Transforms/LoopFusion/diagnostics_analysis.ll (30658 of 46848)
PASS: LLVM :: Transforms/InstCombine/scalbn-to-ldexp.ll (30659 of 46848)
PASS: LLVM :: CodeGen/X86/2010-06-15-FastAllocEarlyCLobber.ll (30660 of 46848)
PASS: LLVM :: CodeGen/AArch64/tailcall-fastisel.ll (30661 of 46848)
PASS: LLVM :: Transforms/SampleProfile/inline-act.ll (30662 of 46848)
PASS: LLVM :: Transforms/InstCombine/canonicalize-low-bit-mask-v4-and-icmp-ne-to-icmp-ugt.ll (30663 of 46848)
PASS: LLVM :: Transforms/LoopSimplify/dbg-loc.ll (30664 of 46848)
PASS: LLVM :: CodeGen/BPF/preserve-static-offset/store-undo-volatile.ll (30665 of 46848)
PASS: LLVM :: DebugInfo/Generic/assignment-tracking/sroa/complex.ll (30666 of 46848)
PASS: LLVM :: Transforms/Coroutines/coro-alloc-with-param-O0.ll (30667 of 46848)
PASS: LLVM :: Transforms/JumpThreading/thread-debug-info.ll (30668 of 46848)
PASS: LLVM :: Transforms/InstCombine/select-icmp-xor.ll (30669 of 46848)
PASS: LLVM :: Transforms/LoopSimplifyCFG/pr39783.ll (30670 of 46848)
PASS: LLVM :: Assembler/2007-03-19-NegValue.ll (30671 of 46848)
PASS: LLVM :: Transforms/SLPVectorizer/X86/pr16628.ll (30672 of 46848)
PASS: LLVM :: CodeGen/DirectX/any.ll (30673 of 46848)
PASS: LLVM :: Transforms/ConstraintElimination/geps-unsigned-predicates.ll (30674 of 46848)
PASS: LLVM :: Transforms/IndVarSimplify/2011-11-17-selfphi.ll (30675 of 46848)
PASS: LLVM :: Transforms/RewriteStatepointsForGC/base-inference.ll (30676 of 46848)
PASS: LLVM :: Analysis/LoopAccessAnalysis/load-store-index-loaded-in-loop.ll (30677 of 46848)
PASS: LLVM :: Transforms/RelLookupTableConverter/X86/opaque-ptr.ll (30678 of 46848)
PASS: LLVM :: Transforms/LICM/explicit_guards.ll (30679 of 46848)
PASS: LLVM :: Transforms/JumpThreading/branch-debug-info.ll (30680 of 46848)
PASS: LLVM :: Transforms/InstCombine/pr38897.ll (30681 of 46848)
PASS: LLVM :: CodeGen/AArch64/phi-dbg.ll (30682 of 46848)
PASS: LLVM :: Transforms/GlobalOpt/sra-many-stores.ll (30683 of 46848)
PASS: LLVM :: CodeGen/VE/Vector/vp_reduce_smax.ll (30684 of 46848)
PASS: LLVM :: Transforms/InstSimplify/ConstProp/basictest.ll (30685 of 46848)
PASS: LLVM :: Transforms/InstSimplify/result-of-usub-is-non-zero-and-no-overflow.ll (30686 of 46848)
PASS: LLVM :: CodeGen/MSP430/2009-11-20-NewNode.ll (30687 of 46848)
PASS: LLVM :: FileCheck/check-literal.txt (30688 of 46848)
PASS: LLVM :: DebugInfo/ARM/move-dbg-values.mir (30689 of 46848)
PASS: LLVM :: Transforms/SpeculativeExecution/spec-casts.ll (30690 of 46848)
PASS: LLVM :: Transforms/NewGVN/crash-no-aa.ll (30691 of 46848)
PASS: LLVM :: CodeGen/SystemZ/tdc-07.ll (30692 of 46848)
PASS: LLVM :: Transforms/InstSimplify/freeze.ll (30693 of 46848)
PASS: LLVM :: CodeGen/Thumb/triple.ll (30694 of 46848)
PASS: LLVM :: Transforms/SimplifyCFG/poison-merge.ll (30695 of 46848)

```

</details>

https://github.com/llvm/llvm-project/pull/221694