[llvm] [IR] Remove unnecessary setDebugLoc calls. NFCI. (PR #218663)

[Jay Foad via llvm-commits]

https://github.com/jayfoad created https://github.com/llvm/llvm-project/pull/218663

If we are already calling copyMetadata to copy metadata including MD_dbg
from an old instruction to a newly created one then there is no need to
call setDebugLoc to copy the debug metadata again.


>From b0de391a7faa69eb2b3f930839bef0c82826c53e Mon Sep 17 00:00:00 2001
From: Jay Foad <jay.foad at amd.com>
Date: Tue, 25 Aug 2026 11:50:31 +0100
Subject: [PATCH] [IR] Remove unnecessary setDebugLoc calls. NFCI.

If we are already calling copyMetadata to copy metadata including MD_dbg
from an old instruction to a newly created one then there is no need to
call setDebugLoc to copy the debug metadata again.
---
 llvm/lib/IR/AutoUpgrade.cpp                            |  2 --
 llvm/lib/Target/NVPTX/NVPTXLowerAlloca.cpp             |  1 -
 .../Transforms/InstCombine/InstructionCombining.cpp    | 10 +++++-----
 llvm/lib/Transforms/Utils/Local.cpp                    |  1 -
 4 files changed, 5 insertions(+), 9 deletions(-)

diff --git a/llvm/lib/IR/AutoUpgrade.cpp b/llvm/lib/IR/AutoUpgrade.cpp
index 9865816e36959..0723598342c23 100644
--- a/llvm/lib/IR/AutoUpgrade.cpp
+++ b/llvm/lib/IR/AutoUpgrade.cpp
@@ -5089,7 +5089,6 @@ static Value *upgradeAMDGCNIntrinsicCall(StringRef Name, CallBase *CI,
     NewCall->setTailCallKind(cast<CallInst>(CI)->getTailCallKind());
     NewCall->setCallingConv(CI->getCallingConv());
     NewCall->setAttributes(CI->getAttributes());
-    NewCall->setDebugLoc(CI->getDebugLoc());
     NewCall->copyMetadata(*CI);
     return NewCall;
   };
@@ -5146,7 +5145,6 @@ static Value *upgradeAMDGCNIntrinsicCall(StringRef Name, CallBase *CI,
     NewCall->setTailCallKind(cast<CallInst>(CI)->getTailCallKind());
     NewCall->setCallingConv(CI->getCallingConv());
     NewCall->setAttributes(CI->getAttributes());
-    NewCall->setDebugLoc(CI->getDebugLoc());
     NewCall->copyMetadata(*CI);
     NewCall->takeName(CI);
     return NewCall;
diff --git a/llvm/lib/Target/NVPTX/NVPTXLowerAlloca.cpp b/llvm/lib/Target/NVPTX/NVPTXLowerAlloca.cpp
index 2ad87d8d068ad..244c0343960a2 100644
--- a/llvm/lib/Target/NVPTX/NVPTXLowerAlloca.cpp
+++ b/llvm/lib/Target/NVPTX/NVPTXLowerAlloca.cpp
@@ -57,7 +57,6 @@ static bool lowerAllocas(Function &F) {
     auto *LocalAlloca = new AllocaInst(AI->getAllocatedType(),
                                        ADDRESS_SPACE_LOCAL, AI->getArraySize(),
                                        AI->getAlign(), "", AI->getIterator());
-    LocalAlloca->setDebugLoc(AI->getDebugLoc());
     LocalAlloca->copyMetadata(*AI);
     LocalAlloca->setUsedWithInAlloca(AI->isUsedWithInAlloca());
     LocalAlloca->setSwiftError(AI->isSwiftError());
diff --git a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
index 6aa33b0821f10..b877f79a000cf 100644
--- a/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
+++ b/llvm/lib/Transforms/InstCombine/InstructionCombining.cpp
@@ -77,6 +77,7 @@
 #include "llvm/IR/Instructions.h"
 #include "llvm/IR/IntrinsicInst.h"
 #include "llvm/IR/Intrinsics.h"
+#include "llvm/IR/LLVMContext.h"
 #include "llvm/IR/Metadata.h"
 #include "llvm/IR/Operator.h"
 #include "llvm/IR/PassManager.h"
@@ -1836,12 +1837,11 @@ Instruction *InstCombinerImpl::FoldOpIntoSelect(Instruction &Op, SelectInst *SI,
 
   SelectInst *NewSel = SelectInst::Create(SI->getCondition(), NewTV, NewFV);
 
-  // Preserve metadata that remains valid for the transformed select.
+  // Preserve metadata that remains valid for the transformed select including
+  // source location information.
   NewSel->copyMetadata(*SI,
-                       {LLVMContext::MD_prof, LLVMContext::MD_unpredictable});
-
-  // Preserve source location information.
-  NewSel->setDebugLoc(SI->getDebugLoc());
+                       {LLVMContext::MD_prof, LLVMContext::MD_unpredictable,
+                        LLVMContext::MD_dbg});
 
   return NewSel;
 }
diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 29bd7c4dba51e..717765ca03b42 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -2601,7 +2601,6 @@ CallInst *llvm::createCallMatchingInvoke(InvokeInst *II) {
                                        II->getCalledOperand(), Args, OpBundles);
   NewCall->setCallingConv(II->getCallingConv());
   NewCall->setAttributes(II->getAttributes());
-  NewCall->setDebugLoc(II->getDebugLoc());
   NewCall->copyMetadata(*II);
 
   // If the invoke had profile metadata, try converting them for CallInst.