[llvm-branch-commits] [llvm] [InstrProf] Deduplicate VP values (PR #196649)

[Aiden Grossman via llvm-branch-commits]

https://github.com/boomanaiden154 updated https://github.com/llvm/llvm-project/pull/196649

>From aa1e92c87136d749b274e98beefde43327eb7c36 Mon Sep 17 00:00:00 2001
From: Aiden Grossman <aidengrossman at google.com>
Date: Fri, 8 May 2026 21:45:12 +0000
Subject: [PATCH 1/2] fix

Created using spr 1.3.7
---
 llvm/lib/ProfileData/InstrProf.cpp | 4 ++++
 1 file changed, 4 insertions(+)

diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp
index f669f53589306..1c2e3a5e145e7 100644
--- a/llvm/lib/ProfileData/InstrProf.cpp
+++ b/llvm/lib/ProfileData/InstrProf.cpp
@@ -1049,6 +1049,10 @@ void InstrProfRecord::addValueData(uint32_t ValueKind, uint32_t Site,
                                    InstrProfSymtab *ValueMap) {
   // Remap values.
   std::vector<InstrProfValueData> RemappedVD;
+  // Zero values might occur multiple times (e.g., multiple functions that
+  // cannot be remapped). Deduplicate them to enforce the variant that
+  // values are unique, which allows passes to make some simplifying
+  // assumptions.
   std::optional<size_t> ZeroIndex = std::nullopt;
   RemappedVD.reserve(VData.size());
   for (const auto &V : VData) {

>From ffb2cfc8b2189d91c8381b719ce26e32c4c74f29 Mon Sep 17 00:00:00 2001
From: Aiden Grossman <aidengrossman at google.com>
Date: Thu, 14 May 2026 13:27:12 +0000
Subject: [PATCH 2/2] feedback

Created using spr 1.3.7
---
 llvm/lib/ProfileData/InstrProf.cpp | 11 ++++-------
 1 file changed, 4 insertions(+), 7 deletions(-)

diff --git a/llvm/lib/ProfileData/InstrProf.cpp b/llvm/lib/ProfileData/InstrProf.cpp
index 5ddfe1a9b69ec..628be437f05a8 100644
--- a/llvm/lib/ProfileData/InstrProf.cpp
+++ b/llvm/lib/ProfileData/InstrProf.cpp
@@ -1370,17 +1370,14 @@ void annotateValueSite(Module &M, Instruction &Inst,
   // These are rare and should only come from corrupted profiles, so we
   // just skip them. Remove this when they are fixed properly in
   // llvm-profdata.
-  std::optional<uint64_t> ZeroCount = std::nullopt;
+  uint64_t ZeroCount = 0;
   DenseSet<uint64_t> VisitedValues;
   for (const auto &VD : VDs) {
     if (VD.Value != 0 && VisitedValues.contains(VD.Value))
       continue;
     VisitedValues.insert(VD.Value);
     if (VD.Value == 0) {
-      if (ZeroCount.has_value())
-        ZeroCount = *ZeroCount + VD.Count;
-      else
-        ZeroCount = VD.Count;
+      ZeroCount += VD.Count;
     } else {
       Vals.push_back(MDHelper.createConstant(
           ConstantInt::get(Type::getInt64Ty(Ctx), VD.Value)));
@@ -1390,11 +1387,11 @@ void annotateValueSite(Module &M, Instruction &Inst,
     if (--MDCount == 0)
       break;
   }
-  if (ZeroCount.has_value()) {
+  if (ZeroCount != 0) {
     Vals.push_back(
         MDHelper.createConstant(ConstantInt::get(Type::getInt64Ty(Ctx), 0)));
     Vals.push_back(MDHelper.createConstant(
-        ConstantInt::get(Type::getInt64Ty(Ctx), *ZeroCount)));
+        ConstantInt::get(Type::getInt64Ty(Ctx), ZeroCount)));
   }
   Inst.setMetadata(LLVMContext::MD_prof, MDNode::get(Ctx, Vals));
 }