Add missing compiler-rt files from emscripten (#6)

Author: aheejin

compiler-rt/__trap.c

@@ -0,0 +1,3 @@
+void __trap() {
+  __builtin_trap();
+}

compiler-rt/emscripten_exception_builtins.c

@@ -0,0 +1,23 @@
+/*
+ * Copyright 2018 The Emscripten Authors.  All rights reserved.
+ * Emscripten is available under two separate licenses, the MIT license and the
+ * University of Illinois/NCSA Open Source License.  Both these licenses can be
+ * found in the LICENSE file.
+ *
+ * Support functions for emscripten setjmp/longjmp and exception handling
+ * support. References to the things below are generated in the LLVM backend.
+ * See: https://llvm.org/doxygen/WebAssemblyLowerEmscriptenEHSjLj_8cpp.html
+ */
+
+#include <stdint.h>
+#include <threads.h>
+
+thread_local uintptr_t __THREW__ = 0;
+thread_local int __threwValue = 0;
+
+void setThrew(uintptr_t threw, int value) {
+  if (__THREW__ == 0) {
+    __THREW__ = threw;
+    __threwValue = value;
+  }
+}

compiler-rt/emscripten_setjmp.c

@@ -0,0 +1,93 @@
+/*
+* Copyright 2020 The Emscripten Authors.  All rights reserved.
+* Emscripten is available under two separate licenses, the MIT license and the
+* University of Illinois/NCSA Open Source License.  Both these licenses can be
+* found in the LICENSE file.
+*/
+
+#include <stdint.h>
+#include <stdlib.h>
+#include <setjmp.h>
+#include <threads.h>
+
+// 0 - Nothing thrown
+// 1 - Exception thrown
+// Other values - jmpbuf pointer in the case that longjmp was thrown
+static uintptr_t setjmpId = 0;
+
+typedef struct TableEntry {
+  uintptr_t id;
+  uint32_t label;
+} TableEntry;
+
+extern void setTempRet0(uint32_t value);
+extern void setThrew(uintptr_t threw, int value);
+
+TableEntry* saveSetjmp(uintptr_t* env, uint32_t label, TableEntry* table, uint32_t size) {
+  // Not particularly fast: slow table lookup of setjmpId to label. But setjmp
+  // prevents relooping anyhow, so slowness is to be expected. And typical case
+  // is 1 setjmp per invocation, or less.
+  uint32_t i = 0;
+  setjmpId++;
+  *env = setjmpId;
+  while (i < size) {
+    if (table[i].id == 0) {
+      table[i].id = setjmpId;
+      table[i].label = label;
+      // prepare next slot
+      table[i + 1].id = 0;
+      setTempRet0(size);
+      return table;
+    }
+    i++;
+  }
+  // grow the table
+  size *= 2;
+  table = (TableEntry*)realloc(table, sizeof(TableEntry) * (size +1));
+  table = saveSetjmp(env, label, table, size);
+  setTempRet0(size); // FIXME: unneeded?
+  return table;
+}
+
+uint32_t testSetjmp(uintptr_t id, TableEntry* table, uint32_t size) {
+  uint32_t i = 0;
+  while (i < size) {
+    uintptr_t curr = table[i].id;
+    if (curr == 0) break;
+    if (curr == id) {
+      return table[i].label;
+    }
+    i++;
+  }
+  return 0;
+}
+
+#if !defined(__USING_WASM_SJLJ__)
+
+#include "emscripten_internal.h"
+
+void emscripten_longjmp(uintptr_t env, int val) {
+  setThrew(env, val);
+  _emscripten_throw_longjmp();
+}
+#endif
+
+#ifdef __USING_WASM_SJLJ__
+
+struct __WasmLongjmpArgs {
+  void *env;
+  int val;
+};
+
+thread_local struct __WasmLongjmpArgs __wasm_longjmp_args;
+
+// Wasm EH allows us to throw and catch multiple values, but that requires
+// multivalue support in the toolchain, whch is not reliable at the time.
+// TODO Consider switching to throwing two values at the same time later.
+void __wasm_longjmp(void *env, int val) {
+  __wasm_longjmp_args.env = env;
+  __wasm_longjmp_args.val = val;
+  __builtin_wasm_throw(1, &__wasm_longjmp_args);
+}
+
+#endif

compiler-rt/emscripten_tempret.s

@@ -0,0 +1,26 @@
+.globaltype tempRet0, i32
+tempRet0:
+
+.globl setTempRet0
+setTempRet0:
+  .functype setTempRet0 (i32) -> ()
+  local.get 0
+  global.set tempRet0
+  end_function
+
+.globl getTempRet0
+getTempRet0:
+  .functype getTempRet0 () -> (i32)
+  global.get tempRet0
+  end_function
+
+# These aliases exist solely for LegalizeJSInterface pass in binaryen
+# They get exported by emcc and the exports are then removed by the
+# binaryen pass
+.globl __get_temp_ret
+.type __get_temp_ret, @function
+__get_temp_ret = getTempRet0
+
+.globl __set_temp_ret
+.type __set_temp_ret, @function
+__set_temp_ret = setTempRet0

compiler-rt/lib/asan/asan_emscripten.cpp

@@ -0,0 +1,116 @@
+#include "asan_interceptors.h"
+#include "asan_internal.h"
+#include "asan_mapping.h"
+#include "asan_poisoning.h"
+#include "asan_stack.h"
+#include "asan_thread.h"
+#include "lsan/lsan_common.h"  // for CAN_SANITIZE_LEAKS
+
+#if SANITIZER_EMSCRIPTEN
+#include <emscripten.h>
+#include <emscripten/heap.h>
+#include <cassert>
+#include <cstddef>
+#include <pthread.h>
+#define __ATTRP_C11_THREAD ((void*)(uptr)-1)
+
+namespace __asan {
+
+void InitializeShadowMemory() {
+  // Poison the shadow memory of the shadow area at the start of the address
+  // space. This helps catching null pointer dereference.
+  FastPoisonShadow(kLowShadowBeg, kLowShadowEnd - kLowShadowBeg, 0xff);
+
+  // Assert that the shadow region is large enough.  We don't want to start
+  // running into the static data region which starts right after the shadow
+  // region.
+  uptr max_address =
+    (__builtin_wasm_memory_size(0) * uint64_t(WASM_PAGE_SIZE)) - 1;
+  uptr max_shadow_address = MEM_TO_SHADOW(max_address);
+  // TODO(sbc): In the growable memory case we should really be checking this
+  // every time we grow.
+  assert(max_shadow_address <= kLowShadowEnd && "shadow region is too small");
+}
+
+void AsanCheckDynamicRTPrereqs() {}
+void AsanCheckIncompatibleRT() {}
+void InitializePlatformInterceptors() {}
+void InitializePlatformExceptionHandlers() {}
+bool IsSystemHeapAddress (uptr addr) { return false; }
+
+void *AsanDoesNotSupportStaticLinkage() {
+  // On Linux, this is some magic that fails linking with -static.
+  // On Emscripten, we have to do static linking, so we stub this out.
+  return nullptr;
+}
+
+void InitializeAsanInterceptors() {}
+
+void FlushUnneededASanShadowMemory(uptr p, uptr size) {}
+
+extern "C" {
+int emscripten_builtin_pthread_create(pthread_t *thread,
+                                      const pthread_attr_t *attr,
+                                      void *(*callback)(void *), void *arg);
+}
+
+static thread_return_t THREAD_CALLING_CONV asan_thread_start(void *arg) {
+  AsanThread *t = (AsanThread *)arg;
+  SetCurrentThread(t);
+  return t->ThreadStart(GetTid());
+}
+
+INTERCEPTOR(int, pthread_create, pthread_t *thread,
+    const pthread_attr_t *attr, void *(*start_routine)(void*), void *arg) {
+  EnsureMainThreadIDIsCorrect();
+  // Strict init-order checking is thread-hostile.
+  if (flags()->strict_init_order)
+    StopInitOrderChecking();
+  GET_STACK_TRACE_THREAD;
+  int detached = 0;
+  if (attr && attr != __ATTRP_C11_THREAD)
+    pthread_attr_getdetachstate(attr, &detached);
+
+  u32 current_tid = GetCurrentTidOrInvalid();
+  AsanThread *t =
+      AsanThread::Create(start_routine, arg, current_tid, &stack, detached);
+
+  int result;
+  {
+    // Ignore all allocations made by pthread_create: thread stack/TLS may be
+    // stored by pthread for future reuse even after thread destruction, and
+    // the linked list it's stored in doesn't even hold valid pointers to the
+    // objects, the latter are calculated by obscure pointer arithmetic.
+#if CAN_SANITIZE_LEAKS
+    __lsan::ScopedInterceptorDisabler disabler;
+#endif
+    result = REAL(pthread_create)(thread, attr, asan_thread_start, t);
+  }
+  if (result != 0) {
+    // If the thread didn't start delete the AsanThread to avoid leaking it.
+    // Note AsanThreadContexts never get destroyed so the AsanThreadContext
+    // that was just created for the AsanThread is wasted.
+    t->Destroy();
+  }
+  return result;
+}
+
+} // namespace __asan
+
+namespace __lsan {
+
+#ifndef __EMSCRIPTEN_PTHREADS__
+// XXX HACK: Emscripten treats thread_local variables the same as globals in
+// non-threaded builds, so a hack was introduced where we skip the allocator
+// cache in the common module. Now we have to define this symbol to keep that
+// hack working when using LSan as part of ASan without threads.
+void GetAllocatorCacheRange(uptr *begin, uptr *end) {
+  *begin = *end = 0;
+}
+#endif
+
+u32 GetCurrentThread() { return __asan::GetCurrentThread()->tid(); }
+
+} // namespace __lsan
+
+#endif // SANITIZER_EMSCRIPTEN

compiler-rt/lib/asan/asan_mapping_emscripten.h

@@ -0,0 +1,88 @@
+//===-- asan_mapping_emscripten.h -------------------------------*- C++ -*-===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is a part of AddressSanitizer, an address sanity checker.
+//
+// Emscripten-specific definitions for ASan memory mapping.
+//===----------------------------------------------------------------------===//
+#ifndef ASAN_MAPPING_EMSCRIPTEN_H
+#define ASAN_MAPPING_EMSCRIPTEN_H
+
+extern char __global_base;
+
+#define kLowMemBeg     ((uptr) &__global_base)
+#define kLowMemEnd     ((kLowShadowBeg << ASAN_SHADOW_SCALE) - 1)
+
+#define kLowShadowBeg  0
+#define kLowShadowEnd  ((uptr) &__global_base - 1)
+
+#define kHighMemBeg    0
+
+#define kHighShadowBeg 0
+#define kHighShadowEnd 0
+
+#define kMidShadowBeg  0
+#define kMidShadowEnd  0
+
+#define kShadowGapBeg  (kLowMemEnd + 1)
+#define kShadowGapEnd  0xFFFFFFFF
+
+#define kShadowGap2Beg 0
+#define kShadowGap2End 0
+
+#define kShadowGap3Beg 0
+#define kShadowGap3End 0
+
+// The first 1/8 of the shadow memory space is shadowing itself.
+// This allows attempted accesses into the shadow memory, as well as null
+// pointer dereferences, to be detected properly.
+// The shadow memory of the shadow memory is poisoned.
+#define MEM_TO_SHADOW(mem) ((mem) >> ASAN_SHADOW_SCALE)
+#define SHADOW_TO_MEM(mem) ((mem) << ASAN_SHADOW_SCALE)
+
+namespace __asan {
+
+static inline bool AddrIsInLowMem(uptr a) {
+  PROFILE_ASAN_MAPPING();
+  return a >= kLowMemBeg && a <= kLowMemEnd;
+}
+
+static inline bool AddrIsInLowShadow(uptr a) {
+  PROFILE_ASAN_MAPPING();
+  return a >= kLowShadowBeg && a <= kLowShadowEnd;
+}
+
+static inline bool AddrIsInMidMem(uptr a) {
+  PROFILE_ASAN_MAPPING();
+  return false;
+}
+
+static inline bool AddrIsInMidShadow(uptr a) {
+  PROFILE_ASAN_MAPPING();
+  return false;
+}
+
+static inline bool AddrIsInHighMem(uptr a) {
+  PROFILE_ASAN_MAPPING();
+  return false;
+}
+
+static inline bool AddrIsInHighShadow(uptr a) {
+  PROFILE_ASAN_MAPPING();
+  return false;
+}
+
+static inline bool AddrIsInShadowGap(uptr a) {
+  PROFILE_ASAN_MAPPING();
+  return a >= kShadowGapBeg;
+}
+
+}  // namespace __asan
+
+#endif  // ASAN_MAPPING_EMSCRIPTEN_H