From b06fbdeae752e59cdf36a1cd26be8a6dcd51e862 Mon Sep 17 00:00:00 2001
From: Leonard Chan <leonardchan@google.com>
Date: Fri, 18 Jun 2021 11:10:38 -0700
Subject: [PATCH] [compiler-rt][hwasan] Add InitState options to thread
 initialization

Similar to InitOptions in asan, we can use this optional struct for
initializing some members thread objects before they are created. On
linux, this is unused and can remain undefined. On fuchsia, this will
just be the stack bounds.

Differential Revision: https://reviews.llvm.org/D104553
---
 compiler-rt/lib/hwasan/hwasan_linux.cpp     | 2 +-
 compiler-rt/lib/hwasan/hwasan_thread.cpp    | 5 +++--
 compiler-rt/lib/hwasan/hwasan_thread.h      | 8 ++++++--
 compiler-rt/lib/hwasan/hwasan_thread_list.h | 4 ++--
 4 files changed, 12 insertions(+), 7 deletions(-)

diff --git a/compiler-rt/lib/hwasan/hwasan_linux.cpp b/compiler-rt/lib/hwasan/hwasan_linux.cpp
index bc5ac3b7bae5..12bea5ca0844 100644
--- a/compiler-rt/lib/hwasan/hwasan_linux.cpp
+++ b/compiler-rt/lib/hwasan/hwasan_linux.cpp
@@ -428,7 +428,7 @@ void HwasanOnDeadlySignal(int signo, void *info, void *context) {
   HandleDeadlySignal(info, context, GetTid(), &OnStackUnwind, nullptr);
 }
 
-void Thread::InitStackAndTls() {
+void Thread::InitStackAndTls(const InitState *) {
   uptr tls_size;
   uptr stack_size;
   GetThreadStackAndTls(IsMainThread(), &stack_bottom_, &stack_size, &tls_begin_,
diff --git a/compiler-rt/lib/hwasan/hwasan_thread.cpp b/compiler-rt/lib/hwasan/hwasan_thread.cpp
index 694948477132..764ca4f651b3 100644
--- a/compiler-rt/lib/hwasan/hwasan_thread.cpp
+++ b/compiler-rt/lib/hwasan/hwasan_thread.cpp
@@ -34,7 +34,8 @@ void Thread::InitRandomState() {
     stack_allocations_->push(0);
 }
 
-void Thread::Init(uptr stack_buffer_start, uptr stack_buffer_size) {
+void Thread::Init(uptr stack_buffer_start, uptr stack_buffer_size,
+                  const InitState *state) {
   CHECK_EQ(0, unique_id_);  // try to catch bad stack reuse
   CHECK_EQ(0, stack_top_);
   CHECK_EQ(0, stack_bottom_);
@@ -44,7 +45,7 @@ void Thread::Init(uptr stack_buffer_start, uptr stack_buffer_size) {
   if (auto sz = flags()->heap_history_size)
     heap_allocations_ = HeapAllocationsRingBuffer::New(sz);
 
-  InitStackAndTls();
+  InitStackAndTls(state);
   InitStackRingBuffer(stack_buffer_start, stack_buffer_size);
 }
 
diff --git a/compiler-rt/lib/hwasan/hwasan_thread.h b/compiler-rt/lib/hwasan/hwasan_thread.h
index 25dee5a5b60e..9f20afe1dc76 100644
--- a/compiler-rt/lib/hwasan/hwasan_thread.h
+++ b/compiler-rt/lib/hwasan/hwasan_thread.h
@@ -23,9 +23,13 @@ typedef __sanitizer::CompactRingBuffer<uptr> StackAllocationsRingBuffer;
 
 class Thread {
  public:
-  void Init(uptr stack_buffer_start, uptr stack_buffer_size);
+  // These are optional parameters that can be passed to Init.
+  struct InitState;
+
+  void Init(uptr stack_buffer_start, uptr stack_buffer_size,
+            const InitState *state = nullptr);
   void InitRandomState();
-  void InitStackAndTls();
+  void InitStackAndTls(const InitState *state = nullptr);
 
   // Must be called from the thread itself.
   void InitStackRingBuffer(uptr stack_buffer_start, uptr stack_buffer_size);
diff --git a/compiler-rt/lib/hwasan/hwasan_thread_list.h b/compiler-rt/lib/hwasan/hwasan_thread_list.h
index d726fa7b477a..8e6c8adf1e59 100644
--- a/compiler-rt/lib/hwasan/hwasan_thread_list.h
+++ b/compiler-rt/lib/hwasan/hwasan_thread_list.h
@@ -85,7 +85,7 @@ class HwasanThreadList {
         RoundUpTo(ring_buffer_size_ + sizeof(Thread), ring_buffer_size_ * 2);
   }
 
-  Thread *CreateCurrentThread() {
+  Thread *CreateCurrentThread(const Thread::InitState *state = nullptr) {
     Thread *t = nullptr;
     {
       SpinMutexLock l(&free_list_mutex_);
@@ -104,7 +104,7 @@ class HwasanThreadList {
       SpinMutexLock l(&live_list_mutex_);
       live_list_.push_back(t);
     }
-    t->Init((uptr)t - ring_buffer_size_, ring_buffer_size_);
+    t->Init((uptr)t - ring_buffer_size_, ring_buffer_size_, state);
     AddThreadStats(t);
     return t;
   }