diff --git a/src/hotspot/cpu/x86/stubGenerator_x86_64_adler.cpp b/src/hotspot/cpu/x86/stubGenerator_x86_64_adler.cpp
index bb8e8f6b1ea..84f5cc80b0d 100644
--- a/src/hotspot/cpu/x86/stubGenerator_x86_64_adler.cpp
+++ b/src/hotspot/cpu/x86/stubGenerator_x86_64_adler.cpp
@@ -330,6 +330,7 @@ address StubGenerator::generate_updateBytesAdler32() {
   __ movq(r13, xtmp4);
   __ movq(r12, xtmp3);
 
+  __ vzeroupper();
   __ leave();
   __ ret(0);
 
diff --git a/src/hotspot/cpu/x86/stubGenerator_x86_64_chacha.cpp b/src/hotspot/cpu/x86/stubGenerator_x86_64_chacha.cpp
index f94297ce82d..47354f4fc7c 100644
--- a/src/hotspot/cpu/x86/stubGenerator_x86_64_chacha.cpp
+++ b/src/hotspot/cpu/x86/stubGenerator_x86_64_chacha.cpp
@@ -291,6 +291,9 @@ address StubGenerator::generate_chacha20Block_avx() {
   // registers.  That length should be returned through %rax.
   __ mov64(rax, outlen);
 
+  if (outlen == 256) {
+    __ vzeroupper();
+  }
   __ leave();
   __ ret(0);
   return start;
@@ -460,6 +463,7 @@ address StubGenerator::generate_chacha20Block_avx512() {
   // and that length should be returned through %rax.
   __ mov64(rax, 1024);
 
+  __ vzeroupper();
   __ leave();
   __ ret(0);
   return start;
diff --git a/src/hotspot/share/opto/library_call.cpp b/src/hotspot/share/opto/library_call.cpp
index 62d78580953..6e104f09b9d 100644
--- a/src/hotspot/share/opto/library_call.cpp
+++ b/src/hotspot/share/opto/library_call.cpp
@@ -1112,6 +1112,7 @@ bool LibraryCallKit::inline_countPositives() {
   Node* ba_start = array_element_address(ba, offset, T_BYTE);
   Node* result = new CountPositivesNode(control(), memory(TypeAryPtr::BYTES), ba_start, len);
   set_result(_gvn.transform(result));
+  clear_upper_avx();
   return true;
 }
 
@@ -1366,6 +1367,7 @@ bool LibraryCallKit::inline_string_indexOfChar(StrIntrinsicNode::ArgEnc ae) {
   set_control(_gvn.transform(region));
   record_for_igvn(region);
   set_result(_gvn.transform(phi));
+  clear_upper_avx();
 
   return true;
 }