diff --git a/llvm/lib/Transforms/Utils/Local.cpp b/llvm/lib/Transforms/Utils/Local.cpp
index 95f0d099aacb5..edec0e7a94422 100644
--- a/llvm/lib/Transforms/Utils/Local.cpp
+++ b/llvm/lib/Transforms/Utils/Local.cpp
@@ -3355,8 +3355,12 @@ static void combineMetadata(Instruction *K, const Instruction *J,
       case LLVMContext::MD_invariant_group:
         // Preserve !invariant.group in K.
         break;
+      // Keep empty cases for mmra, memprof, and callsite to prevent them from
+      // being removed as unknown metadata. The actual merging is handled
+      // separately below.
       case LLVMContext::MD_mmra:
-        // Combine MMRAs
+      case LLVMContext::MD_memprof:
+      case LLVMContext::MD_callsite:
         break;
       case LLVMContext::MD_align:
         if (!AAOnly && (DoesKMove || !K->hasMetadata(LLVMContext::MD_noundef)))
@@ -3369,14 +3373,6 @@ static void combineMetadata(Instruction *K, const Instruction *J,
           K->setMetadata(Kind,
             MDNode::getMostGenericAlignmentOrDereferenceable(JMD, KMD));
         break;
-      case LLVMContext::MD_memprof:
-        if (!AAOnly)
-          K->setMetadata(Kind, MDNode::getMergedMemProfMetadata(KMD, JMD));
-        break;
-      case LLVMContext::MD_callsite:
-        if (!AAOnly)
-          K->setMetadata(Kind, MDNode::getMergedCallsiteMetadata(KMD, JMD));
-        break;
       case LLVMContext::MD_preserve_access_index:
         // Preserve !preserve.access.index in K.
         break;
@@ -3420,6 +3416,26 @@ static void combineMetadata(Instruction *K, const Instruction *J,
     K->setMetadata(LLVMContext::MD_mmra,
                    MMRAMetadata::combine(K->getContext(), JMMRA, KMMRA));
   }
+
+  // Merge memprof metadata.
+  // Handle separately to support cases where only one instruction has the
+  // metadata.
+  auto *JMemProf = J->getMetadata(LLVMContext::MD_memprof);
+  auto *KMemProf = K->getMetadata(LLVMContext::MD_memprof);
+  if (!AAOnly && (JMemProf || KMemProf)) {
+    K->setMetadata(LLVMContext::MD_memprof,
+                   MDNode::getMergedMemProfMetadata(KMemProf, JMemProf));
+  }
+
+  // Merge callsite metadata.
+  // Handle separately to support cases where only one instruction has the
+  // metadata.
+  auto *JCallSite = J->getMetadata(LLVMContext::MD_callsite);
+  auto *KCallSite = K->getMetadata(LLVMContext::MD_callsite);
+  if (!AAOnly && (JCallSite || KCallSite)) {
+    K->setMetadata(LLVMContext::MD_callsite,
+                   MDNode::getMergedCallsiteMetadata(KCallSite, JCallSite));
+  }
 }
 
 void llvm::combineMetadataForCSE(Instruction *K, const Instruction *J,
diff --git a/llvm/test/Transforms/SimplifyCFG/merge-calls-memprof-left.ll b/llvm/test/Transforms/SimplifyCFG/merge-calls-memprof-left.ll
new file mode 100644
index 0000000000000..d0f83c04b0352
--- /dev/null
+++ b/llvm/test/Transforms/SimplifyCFG/merge-calls-memprof-left.ll
@@ -0,0 +1,46 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+;; Test to ensure that memprof related metadata is not dropped when
+;; instructions are combined. Currently the metadata from the first instruction
+;; is kept, which prevents full loss of profile context information.
+
+; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define dso_local noundef nonnull ptr @_Z9test_leftb(i1 noundef zeroext %b) local_unnamed_addr #0 {
+; CHECK-LABEL: define dso_local noundef nonnull ptr @_Z9test_leftb(
+; CHECK-SAME: i1 noundef zeroext [[B:%.*]]) local_unnamed_addr {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[CALL:%.*]] = call noalias noundef nonnull dereferenceable(4) ptr @_Znwm(i64 noundef 4), !memprof [[META0:![0-9]+]], !callsite [[META3:![0-9]+]]
+; CHECK-NEXT:    ret ptr [[CALL]]
+;
+entry:
+  br i1 %b, label %if.then, label %if.else
+
+if.then:                                          ; preds = %entry
+  %call = call noalias noundef nonnull dereferenceable(4) ptr @_Znwm(i64 noundef 4), !memprof !0, !callsite !3
+  br label %if.end
+
+if.else:                                          ; preds = %entry
+  %call1 = call noalias noundef nonnull dereferenceable(4) ptr @_Znwm(i64 noundef 4)
+  br label %if.end
+
+if.end:                                           ; preds = %if.else, %if.then
+  %x.0 = phi ptr [ %call, %if.then ], [ %call1, %if.else ]
+  ret ptr %x.0
+}
+
+declare ptr @_Znwm(i64) nounwind readonly
+
+!0 = !{!1}
+!1 = !{!2, !"notcold"}
+!2 = !{i64 -852997907418798798, i64 -2101080423462424381, i64 5188446645037944434}
+!3 = !{i64 -852997907418798798}
+
+;.
+; CHECK: [[META0]] = !{[[META1:![0-9]+]]}
+; CHECK: [[META1]] = !{[[META2:![0-9]+]], !"notcold"}
+; CHECK: [[META2]] = !{i64 -852997907418798798, i64 -2101080423462424381, i64 5188446645037944434}
+; CHECK: [[META3]] = !{i64 -852997907418798798}
+;.
diff --git a/llvm/test/Transforms/SimplifyCFG/merge-calls-memprof-right.ll b/llvm/test/Transforms/SimplifyCFG/merge-calls-memprof-right.ll
new file mode 100644
index 0000000000000..463ab865d8810
--- /dev/null
+++ b/llvm/test/Transforms/SimplifyCFG/merge-calls-memprof-right.ll
@@ -0,0 +1,46 @@
+; NOTE: Assertions have been autogenerated by utils/update_test_checks.py UTC_ARGS: --version 5
+;; Test to ensure that memprof related metadata is not dropped when
+;; instructions are combined. Currently the metadata from the first instruction
+;; is kept, which prevents full loss of profile context information.
+
+; RUN: opt < %s -passes=simplifycfg -S | FileCheck %s
+
+target datalayout = "e-m:e-p270:32:32-p271:32:32-p272:64:64-i64:64-i128:128-f80:128-n8:16:32:64-S128"
+target triple = "x86_64-unknown-linux-gnu"
+
+define dso_local noundef nonnull ptr @_Z10test_rightb(i1 noundef zeroext %b) local_unnamed_addr #0 {
+; CHECK-LABEL: define dso_local noundef nonnull ptr @_Z10test_rightb(
+; CHECK-SAME: i1 noundef zeroext [[B:%.*]]) local_unnamed_addr {
+; CHECK-NEXT:  [[ENTRY:.*:]]
+; CHECK-NEXT:    [[CALL:%.*]] = call noalias noundef nonnull dereferenceable(4) ptr @_Znwm(i64 noundef 4), !memprof [[META0:![0-9]+]], !callsite [[META3:![0-9]+]]
+; CHECK-NEXT:    ret ptr [[CALL]]
+;
+entry:
+  br i1 %b, label %if.then, label %if.else
+
+if.then:                                          ; preds = %entry
+  %call = call noalias noundef nonnull dereferenceable(4) ptr @_Znwm(i64 noundef 4)
+  br label %if.end
+
+if.else:                                          ; preds = %entry
+  %call1 = call noalias noundef nonnull dereferenceable(4) ptr @_Znwm(i64 noundef 4), !memprof !4, !callsite !7
+  br label %if.end
+
+if.end:                                           ; preds = %if.else, %if.then
+  %x.0 = phi ptr [ %call, %if.then ], [ %call1, %if.else ]
+  ret ptr %x.0
+}
+
+declare ptr @_Znwm(i64) nounwind readonly
+
+!4 = !{!5}
+!5 = !{!6, !"cold"}
+!6 = !{i64 123, i64 -2101080423462424381, i64 5188446645037944434}
+!7 = !{i64 123}
+
+;.
+; CHECK: [[META0]] = !{[[META1:![0-9]+]]}
+; CHECK: [[META1]] = !{[[META2:![0-9]+]], !"cold"}
+; CHECK: [[META2]] = !{i64 123, i64 -2101080423462424381, i64 5188446645037944434}
+; CHECK: [[META3]] = !{i64 123}
+;.