sanitizer_stacktrace_sparc.cc revision 1.1.1.1 
1//===-- sanitizer_stacktrace_sparc.cc -------------------------------------===//
2//
3//                     The LLVM Compiler Infrastructure
4//
5// This file is distributed under the University of Illinois Open Source
6// License. See LICENSE.TXT for details.
7//
8//===----------------------------------------------------------------------===//
9//
10// This file is shared between AddressSanitizer and ThreadSanitizer
11// run-time libraries.
12//
13// Implemention of fast stack unwinding for Sparc.
14//===----------------------------------------------------------------------===//
15
16// This file is ported to Sparc v8, but it should be easy to port to
17// Sparc v9.
18#if defined(__sparcv8__) || defined(__sparcv8) || defined(__sparc_v8__)
19
20#include "sanitizer_common.h"
21#include "sanitizer_stacktrace.h"
22
23namespace __sanitizer {
24
25void BufferedStackTrace::FastUnwindStack(uptr pc, uptr bp, uptr stack_top,
26                                         uptr stack_bottom, u32 max_depth) {
27  const uptr kPageSize = GetPageSizeCached();
28  CHECK_GE(max_depth, 2);
29  trace_buffer[0] = pc;
30  size = 1;
31  if (stack_top < 4096) return;  // Sanity check for stack top.
32  // Flush register windows to memory
33  asm volatile("ta 3" ::: "memory");
34  uhwptr *frame = (uhwptr*)bp;
35  // Lowest possible address that makes sense as the next frame pointer.
36  // Goes up as we walk the stack.
37  uptr bottom = stack_bottom;
38  // Avoid infinite loop when frame == frame[0] by using frame > prev_frame.
39  while (IsValidFrame((uptr)frame, stack_top, bottom) &&
40         IsAligned((uptr)frame, sizeof(*frame)) &&
41         size < max_depth) {
42    uhwptr pc1 = frame[15];
43    // Let's assume that any pointer in the 0th page is invalid and
44    // stop unwinding here.  If we're adding support for a platform
45    // where this isn't true, we need to reconsider this check.
46    if (pc1 < kPageSize)
47      break;
48    if (pc1 != pc) {
49      trace_buffer[size++] = (uptr) pc1;
50    }
51    bottom = (uptr)frame;
52    frame = (uhwptr*)frame[14];
53  }
54}
55
56}  // namespace __sanitizer
57
58#endif  // !defined(__sparcv8__) && !defined(__sparcv8) &&
59        // !defined(__sparc_v8__)
60