Rollback trunk to 3.21.16.2

src/assembler.cc

Index: src/assembler.cc
diff --git a/src/assembler.cc b/src/assembler.cc
index 6581aa1305a459fdc8c90b31d0a9faabf9f78169..fbff62dd65ef87773461b377ea09f557068c0dc7 100644
--- a/src/assembler.cc
+++ b/src/assembler.cc
@@ -207,26 +207,6 @@ CpuFeatureScope::~CpuFeatureScope() {
 
 
 // -----------------------------------------------------------------------------
-// Implementation of PlatformFeatureScope
-
-PlatformFeatureScope::PlatformFeatureScope(CpuFeature f)
-    : old_supported_(CpuFeatures::supported_),
-      old_found_by_runtime_probing_only_(
-          CpuFeatures::found_by_runtime_probing_only_) {
-  uint64_t mask = static_cast<uint64_t>(1) << f;
-  CpuFeatures::supported_ |= mask;
-  CpuFeatures::found_by_runtime_probing_only_ &= ~mask;
-}
-
-
-PlatformFeatureScope::~PlatformFeatureScope() {
-  CpuFeatures::supported_ = old_supported_;
-  CpuFeatures::found_by_runtime_probing_only_ =
-      old_found_by_runtime_probing_only_;
-}
-
-
-// -----------------------------------------------------------------------------
 // Implementation of Label
 
 int Label::pos() const {