[nolibc] Move libc-dependent sanitizer_linux.cc code to sanitizer_linux_libcdep.cc.

git-svn-id: https://llvm.org/svn/llvm-project/compiler-rt/trunk@182292 91177308-0d34-0410-b5e6-96231b3b80d8

1 files changed, 273 insertions, 0 deletions

diff --git a/lib/sanitizer_common/sanitizer_linux_libcdep.cc b/lib/sanitizer_common/sanitizer_linux_libcdep.cc
new file mode 100644
index 00000000..d9e2f538
--- /dev/null
+++ b/lib/sanitizer_common/sanitizer_linux_libcdep.cc
@@ -0,0 +1,273 @@
+//===-- sanitizer_linux_libcdep.cc ----------------------------------------===//
+//
+//                     The LLVM Compiler Infrastructure
+//
+// This file is distributed under the University of Illinois Open Source
+// License. See LICENSE.TXT for details.
+//
+//===----------------------------------------------------------------------===//
+//
+// This file is shared between AddressSanitizer and ThreadSanitizer
+// run-time libraries and implements linux-specific functions from
+// sanitizer_libc.h.
+//===----------------------------------------------------------------------===//
+
+#include "sanitizer_platform.h"
+#if SANITIZER_LINUX
+
+#include "sanitizer_common.h"
+#include "sanitizer_procmaps.h"
+#include "sanitizer_stacktrace.h"
+
+#ifdef __x86_64__
+#include <asm/prctl.h>
+#endif
+#include <dlfcn.h>
+#include <pthread.h>
+#include <sys/prctl.h>
+#include <sys/resource.h>
+#include <unwind.h>
+
+#ifdef __x86_64__
+extern "C" int arch_prctl(int code, __sanitizer::uptr *addr);
+#endif
+
+namespace __sanitizer {
+
+void GetThreadStackTopAndBottom(bool at_initialization, uptr *stack_top,
+                                uptr *stack_bottom) {
+  static const uptr kMaxThreadStackSize = 256 * (1 << 20);  // 256M
+  CHECK(stack_top);
+  CHECK(stack_bottom);
+  if (at_initialization) {
+    // This is the main thread. Libpthread may not be initialized yet.
+    struct rlimit rl;
+    CHECK_EQ(getrlimit(RLIMIT_STACK, &rl), 0);
+
+    // Find the mapping that contains a stack variable.
+    MemoryMappingLayout proc_maps(/*cache_enabled*/true);
+    uptr start, end, offset;
+    uptr prev_end = 0;
+    while (proc_maps.Next(&start, &end, &offset, 0, 0, /* protection */0)) {
+      if ((uptr)&rl < end)
+        break;
+      prev_end = end;
+    }
+    CHECK((uptr)&rl >= start && (uptr)&rl < end);
+
+    // Get stacksize from rlimit, but clip it so that it does not overlap
+    // with other mappings.
+    uptr stacksize = rl.rlim_cur;
+    if (stacksize > end - prev_end)
+      stacksize = end - prev_end;
+    // When running with unlimited stack size, we still want to set some limit.
+    // The unlimited stack size is caused by 'ulimit -s unlimited'.
+    // Also, for some reason, GNU make spawns subprocesses with unlimited stack.
+    if (stacksize > kMaxThreadStackSize)
+      stacksize = kMaxThreadStackSize;
+    *stack_top = end;
+    *stack_bottom = end - stacksize;
+    return;
+  }
+  pthread_attr_t attr;
+  CHECK_EQ(pthread_getattr_np(pthread_self(), &attr), 0);
+  uptr stacksize = 0;
+  void *stackaddr = 0;
+  pthread_attr_getstack(&attr, &stackaddr, (size_t*)&stacksize);
+  pthread_attr_destroy(&attr);
+
+  *stack_top = (uptr)stackaddr + stacksize;
+  *stack_bottom = (uptr)stackaddr;
+  CHECK(stacksize < kMaxThreadStackSize);  // Sanity check.
+}
+
+// Does not compile for Go because dlsym() requires -ldl
+#ifndef SANITIZER_GO
+bool SetEnv(const char *name, const char *value) {
+  void *f = dlsym(RTLD_NEXT, "setenv");
+  if (f == 0)
+    return false;
+  typedef int(*setenv_ft)(const char *name, const char *value, int overwrite);
+  setenv_ft setenv_f;
+  CHECK_EQ(sizeof(setenv_f), sizeof(f));
+  internal_memcpy(&setenv_f, &f, sizeof(f));
+  return setenv_f(name, value, 1) == 0;
+}
+#endif
+
+bool SanitizerSetThreadName(const char *name) {
+#ifdef PR_SET_NAME
+  return 0 == prctl(PR_SET_NAME, (unsigned long)name, 0, 0, 0);  // NOLINT
+#else
+  return false;
+#endif
+}
+
+bool SanitizerGetThreadName(char *name, int max_len) {
+#ifdef PR_GET_NAME
+  char buff[17];
+  if (prctl(PR_GET_NAME, (unsigned long)buff, 0, 0, 0))  // NOLINT
+    return false;
+  internal_strncpy(name, buff, max_len);
+  name[max_len] = 0;
+  return true;
+#else
+  return false;
+#endif
+}
+
+#ifndef SANITIZER_GO
+//------------------------- SlowUnwindStack -----------------------------------
+#ifdef __arm__
+#define UNWIND_STOP _URC_END_OF_STACK
+#define UNWIND_CONTINUE _URC_NO_REASON
+#else
+#define UNWIND_STOP _URC_NORMAL_STOP
+#define UNWIND_CONTINUE _URC_NO_REASON
+#endif
+
+uptr Unwind_GetIP(struct _Unwind_Context *ctx) {
+#ifdef __arm__
+  uptr val;
+  _Unwind_VRS_Result res = _Unwind_VRS_Get(ctx, _UVRSC_CORE,
+      15 /* r15 = PC */, _UVRSD_UINT32, &val);
+  CHECK(res == _UVRSR_OK && "_Unwind_VRS_Get failed");
+  // Clear the Thumb bit.
+  return val & ~(uptr)1;
+#else
+  return _Unwind_GetIP(ctx);
+#endif
+}
+
+_Unwind_Reason_Code Unwind_Trace(struct _Unwind_Context *ctx, void *param) {
+  StackTrace *b = (StackTrace*)param;
+  CHECK(b->size < b->max_size);
+  uptr pc = Unwind_GetIP(ctx);
+  b->trace[b->size++] = pc;
+  if (b->size == b->max_size) return UNWIND_STOP;
+  return UNWIND_CONTINUE;
+}
+
+static bool MatchPc(uptr cur_pc, uptr trace_pc) {
+  return cur_pc - trace_pc <= 64 || trace_pc - cur_pc <= 64;
+}
+
+void StackTrace::SlowUnwindStack(uptr pc, uptr max_depth) {
+  this->size = 0;
+  this->max_size = max_depth;
+  if (max_depth > 1) {
+    _Unwind_Backtrace(Unwind_Trace, this);
+    // We need to pop a few frames so that pc is on top.
+    // trace[0] belongs to the current function so we always pop it.
+    int to_pop = 1;
+    /**/ if (size > 1 && MatchPc(pc, trace[1])) to_pop = 1;
+    else if (size > 2 && MatchPc(pc, trace[2])) to_pop = 2;
+    else if (size > 3 && MatchPc(pc, trace[3])) to_pop = 3;
+    else if (size > 4 && MatchPc(pc, trace[4])) to_pop = 4;
+    else if (size > 5 && MatchPc(pc, trace[5])) to_pop = 5;
+    this->PopStackFrames(to_pop);
+  }
+  this->trace[0] = pc;
+}
+
+#endif  // !SANITIZER_GO
+
+static uptr g_tls_size;
+
+#ifdef __i386__
+# define DL_INTERNAL_FUNCTION __attribute__((regparm(3), stdcall))
+#else
+# define DL_INTERNAL_FUNCTION
+#endif
+
+void InitTlsSize() {
+#if !defined(SANITIZER_GO) && !SANITIZER_ANDROID
+  typedef void (*get_tls_func)(size_t*, size_t*) DL_INTERNAL_FUNCTION;
+  get_tls_func get_tls;
+  void *get_tls_static_info_ptr = dlsym(RTLD_NEXT, "_dl_get_tls_static_info");
+  CHECK_EQ(sizeof(get_tls), sizeof(get_tls_static_info_ptr));
+  internal_memcpy(&get_tls, &get_tls_static_info_ptr,
+                  sizeof(get_tls_static_info_ptr));
+  CHECK_NE(get_tls, 0);
+  size_t tls_size = 0;
+  size_t tls_align = 0;
+  get_tls(&tls_size, &tls_align);
+  g_tls_size = tls_size;
+#endif
+}
+
+uptr GetTlsSize() {
+  return g_tls_size;
+}
+
+// sizeof(struct thread) from glibc.
+#ifdef __x86_64__
+const uptr kThreadDescriptorSize = 2304;
+
+uptr ThreadDescriptorSize() {
+  return kThreadDescriptorSize;
+}
+#endif
+
+void GetThreadStackAndTls(bool main, uptr *stk_addr, uptr *stk_size,
+                          uptr *tls_addr, uptr *tls_size) {
+#ifndef SANITIZER_GO
+#ifdef __x86_64__
+  arch_prctl(ARCH_GET_FS, tls_addr);
+  *tls_size = GetTlsSize();
+  *tls_addr -= *tls_size;
+  *tls_addr += kThreadDescriptorSize;
+#else
+  *tls_addr = 0;
+  *tls_size = 0;
+#endif
+
+  uptr stack_top, stack_bottom;
+  GetThreadStackTopAndBottom(main, &stack_top, &stack_bottom);
+  *stk_addr = stack_bottom;
+  *stk_size = stack_top - stack_bottom;
+
+  if (!main) {
+    // If stack and tls intersect, make them non-intersecting.
+    if (*tls_addr > *stk_addr && *tls_addr < *stk_addr + *stk_size) {
+      CHECK_GT(*tls_addr + *tls_size, *stk_addr);
+      CHECK_LE(*tls_addr + *tls_size, *stk_addr + *stk_size);
+      *stk_size -= *tls_size;
+      *tls_addr = *stk_addr + *stk_size;
+    }
+  }
+#else  // SANITIZER_GO
+  *stk_addr = 0;
+  *stk_size = 0;
+  *tls_addr = 0;
+  *tls_size = 0;
+#endif  // SANITIZER_GO
+}
+
+void AdjustStackSizeLinux(void *attr_, int verbosity) {
+  pthread_attr_t *attr = (pthread_attr_t *)attr_;
+  uptr stackaddr = 0;
+  size_t stacksize = 0;
+  pthread_attr_getstack(attr, (void**)&stackaddr, &stacksize);
+  // GLibC will return (0 - stacksize) as the stack address in the case when
+  // stacksize is set, but stackaddr is not.
+  bool stack_set = (stackaddr != 0) && (stackaddr + stacksize != 0);
+  // We place a lot of tool data into TLS, account for that.
+  const uptr minstacksize = GetTlsSize() + 128*1024;
+  if (stacksize < minstacksize) {
+    if (!stack_set) {
+      if (verbosity && stacksize != 0)
+        Printf("Sanitizer: increasing stacksize %zu->%zu\n", stacksize,
+               minstacksize);
+      pthread_attr_setstacksize(attr, minstacksize);
+    } else {
+      Printf("Sanitizer: pre-allocated stack size is insufficient: "
+             "%zu < %zu\n", stacksize, minstacksize);
+      Printf("Sanitizer: pthread_create is likely to fail.\n");
+    }
+  }
+}
+
+}  // namespace __sanitizer
+
+#endif  // SANITIZER_LINUX