libsanitizer/sanitizer_common/sanitizer_stacktrace_sparc.cc

   1 //===-- sanitizer_stacktrace_sparc.cc -------------------------------------===//
   2 //
   3 // This file is distributed under the University of Illinois Open Source
   4 // License. See LICENSE.TXT for details.
   5 //
   6 //===----------------------------------------------------------------------===//
   7 //
   8 // This file is shared between AddressSanitizer and ThreadSanitizer
   9 // run-time libraries.
  10 //
  11 // Implemention of fast stack unwinding for Sparc.
  12 //===----------------------------------------------------------------------===//
  13
  14 // This file is ported to Sparc v8, but it should be easy to port to
  15 // Sparc v9.
  16 #if defined(__sparcv8__) || defined(__sparcv8) || defined(__sparc_v8__)
  17
  18 #include "sanitizer_common.h"
  19 #include "sanitizer_stacktrace.h"
  20
  21 namespace __sanitizer {
  22
  23 void BufferedStackTrace::FastUnwindStack(uptr pc, uptr bp, uptr stack_top,
  24                                          uptr stack_bottom, u32 max_depth) {
  25   const uptr kPageSize = GetPageSizeCached();
  26   CHECK_GE(max_depth, 2);
  27   trace_buffer[0] = pc;
  28   size = 1;
  29   if (stack_top < 4096) return;  // Sanity check for stack top.
  30   // Flush register windows to memory
  31   asm volatile("ta 3" ::: "memory");
  32   uhwptr *frame = (uhwptr*)bp;
  33   // Lowest possible address that makes sense as the next frame pointer.
  34   // Goes up as we walk the stack.
  35   uptr bottom = stack_bottom;
  36   // Avoid infinite loop when frame == frame[0] by using frame > prev_frame.
  37   while (IsValidFrame((uptr)frame, stack_top, bottom) &&
  38          IsAligned((uptr)frame, sizeof(*frame)) &&
  39          size < max_depth) {
  40     uhwptr pc1 = frame[15];
  41     // Let's assume that any pointer in the 0th page is invalid and
  42     // stop unwinding here.  If we're adding support for a platform
  43     // where this isn't true, we need to reconsider this check.
  44     if (pc1 < kPageSize)
  45       break;
  46     if (pc1 != pc) {
  47       trace_buffer[size++] = (uptr) pc1;
  48     }
  49     bottom = (uptr)frame;
  50     frame = (uhwptr*)frame[14];
  51   }
  52 }
  53
  54 }  // namespace __sanitizer
  55
  56 #endif  // !defined(__sparcv8__) && !defined(__sparcv8) &&
  57         // !defined(__sparc_v8__)