From e8842d862cee16b5ef2cc1260e8088a5857791e0 Mon Sep 17 00:00:00 2001
From: Ryan Macnak <rmacnak@google.com>
Date: Wed, 8 Feb 2023 17:07:43 +0000
Subject: [PATCH] [vm] Use atomics when setting RegExp bytecode.

TEST=tsan
Bug: https://github.com/dart-lang/sdk/issues/51305
Change-Id: I3e93716d31809be76a4017db68557a9b7263d2f8
Reviewed-on: https://dart-review.googlesource.com/c/sdk/+/281560
Reviewed-by: Alexander Aprelev <aam@google.com>
Commit-Queue: Ryan Macnak <rmacnak@google.com>
---
 runtime/vm/object.cc |  8 ++++----
 runtime/vm/object.h  | 24 +++++++++++++-----------
 2 files changed, 17 insertions(+), 15 deletions(-)

diff --git a/runtime/vm/object.cc b/runtime/vm/object.cc
index 8432df50215..c2c6c11b498 100644
--- a/runtime/vm/object.cc
+++ b/runtime/vm/object.cc
@@ -27184,15 +27184,15 @@ void RegExp::set_bytecode(bool is_one_byte,
                           const TypedData& bytecode) const {
   if (sticky) {
     if (is_one_byte) {
-      untag()->set_one_byte_sticky(bytecode.ptr());
+      untag()->set_one_byte_sticky<std::memory_order_release>(bytecode.ptr());
     } else {
-      untag()->set_two_byte_sticky(bytecode.ptr());
+      untag()->set_two_byte_sticky<std::memory_order_release>(bytecode.ptr());
     }
   } else {
     if (is_one_byte) {
-      untag()->set_one_byte(bytecode.ptr());
+      untag()->set_one_byte<std::memory_order_release>(bytecode.ptr());
     } else {
-      untag()->set_two_byte(bytecode.ptr());
+      untag()->set_two_byte<std::memory_order_release>(bytecode.ptr());
     }
   }
 }
diff --git a/runtime/vm/object.h b/runtime/vm/object.h
index dbfd737dc10..891b1b539d6 100644
--- a/runtime/vm/object.h
+++ b/runtime/vm/object.h
@@ -12484,8 +12484,9 @@ class RegExp : public Instance {
   bool is_complex() const { return (type() == kComplex); }
 
   intptr_t num_registers(bool is_one_byte) const {
-    return is_one_byte ? untag()->num_one_byte_registers_
-                       : untag()->num_two_byte_registers_;
+    return LoadNonPointer<intptr_t, std::memory_order_relaxed>(
+        is_one_byte ? &untag()->num_one_byte_registers_
+                    : &untag()->num_two_byte_registers_);
   }
 
   StringPtr pattern() const { return untag()->pattern(); }
@@ -12496,11 +12497,13 @@ class RegExp : public Instance {
 
   TypedDataPtr bytecode(bool is_one_byte, bool sticky) const {
     if (sticky) {
-      return TypedData::RawCast(is_one_byte ? untag()->one_byte_sticky()
-                                            : untag()->two_byte_sticky());
+      return TypedData::RawCast(
+          is_one_byte ? untag()->one_byte_sticky<std::memory_order_acquire>()
+                      : untag()->two_byte_sticky<std::memory_order_acquire>());
     } else {
-      return TypedData::RawCast(is_one_byte ? untag()->one_byte()
-                                            : untag()->two_byte());
+      return TypedData::RawCast(
+          is_one_byte ? untag()->one_byte<std::memory_order_acquire>()
+                      : untag()->two_byte<std::memory_order_acquire>());
     }
   }
 
@@ -12590,11 +12593,10 @@ class RegExp : public Instance {
   void set_is_simple() const { set_type(kSimple); }
   void set_is_complex() const { set_type(kComplex); }
   void set_num_registers(bool is_one_byte, intptr_t value) const {
-    if (is_one_byte) {
-      StoreNonPointer(&untag()->num_one_byte_registers_, value);
-    } else {
-      StoreNonPointer(&untag()->num_two_byte_registers_, value);
-    }
+    StoreNonPointer<intptr_t, intptr_t, std::memory_order_relaxed>(
+        is_one_byte ? &untag()->num_one_byte_registers_
+                    : &untag()->num_two_byte_registers_,
+        value);
   }
 
   RegExpFlags flags() const {