[llvm] [Transforms] Remove unused wouldInstructionBeTriviallyDeadOnUnusedPaths (PR #218609)

[Kazu Hirata via llvm-commits]

https://github.com/kazutakahirata updated https://github.com/llvm/llvm-project/pull/218609

>From 8f643d1cb6ba6f2b1ad7857bb7628efe99feee67 Mon Sep 17 00:00:00 2001
From: Kazu Hirata <kazu at google.com>
Date: Sun, 9 Aug 2026 01:49:51 -0700
Subject: [PATCH] [Transforms] Remove unused
 wouldInstructionBeTriviallyDeadOnUnusedPaths

This function was added on Dec 1, 2021 in commit
72750f00121eb10f27ccd62270e5695d9e3322a5 without any callers and has
remained unused since.
---
 llvm/include/llvm/Transforms/Utils/Local.h |  8 --------
 llvm/lib/Transforms/Utils/Local.cpp        | 12 ------------
 2 files changed, 20 deletions(-)

diff --git a/llvm/include/llvm/Transforms/Utils/Local.h b/llvm/include/llvm/Transforms/Utils/Local.h
index 4644ca15a946e..a7b687304d63c 100644
--- a/llvm/include/llvm/Transforms/Utils/Local.h
+++ b/llvm/include/llvm/Transforms/Utils/Local.h
@@ -84,14 +84,6 @@ LLVM_ABI bool
 wouldInstructionBeTriviallyDead(const Instruction *I,
                                 const TargetLibraryInfo *TLI = nullptr);
 
-/// Return true if the result produced by the instruction has no side effects on
-/// any paths other than where it is used. This is less conservative than
-/// wouldInstructionBeTriviallyDead which is based on the assumption
-/// that the use count will be 0. An example usage of this API is for
-/// identifying instructions that can be sunk down to use(s).
-LLVM_ABI bool wouldInstructionBeTriviallyDeadOnUnusedPaths(
-    Instruction *I, const TargetLibraryInfo *TLI = nullptr);
-
 /// If the specified value is a trivially dead instruction, delete it.
 /// If that makes any of its operands trivially dead, delete them too,
 /// recursively. Return true if any instructions were deleted.
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 717765ca03b42..6084305241cc3 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -407,18 +407,6 @@ bool llvm::isInstructionTriviallyDead(Instruction *I,
   return wouldInstructionBeTriviallyDead(I, TLI);
 }
 
-bool llvm::wouldInstructionBeTriviallyDeadOnUnusedPaths(
-    Instruction *I, const TargetLibraryInfo *TLI) {
-  // Instructions that are "markers" and have implied meaning on code around
-  // them (without explicit uses), are not dead on unused paths.
-  if (IntrinsicInst *II = dyn_cast<IntrinsicInst>(I))
-    if (II->getIntrinsicID() == Intrinsic::stacksave ||
-        II->getIntrinsicID() == Intrinsic::launder_invariant_group ||
-        II->isLifetimeStartOrEnd())
-      return false;
-  return wouldInstructionBeTriviallyDead(I, TLI);
-}
-
 bool llvm::wouldInstructionBeTriviallyDead(const Instruction *I,
                                            const TargetLibraryInfo *TLI) {
   if (I->isTerminator())