don't remove sinks_ elements.

[platform/upstream/glog.git] / src / stacktrace_powerpc-inl.h

diff --git a/src/stacktrace_powerpc-inl.h b/src/stacktrace_powerpc-inl.h
index 82ce1ab..1090dde 100644 (file)
--- a/src/stacktrace_powerpc-inl.h
+++ b/src/stacktrace_powerpc-inl.h
@@ -1,6 +1,32 @@
-// Copyright 2007 and onwards Google Inc.
+// Copyright (c) 2007, Google Inc.
 // All rights reserved.
 //
+// Redistribution and use in source and binary forms, with or without
+// modification, are permitted provided that the following conditions are
+// met:
+//
+//     * Redistributions of source code must retain the above copyright
+// notice, this list of conditions and the following disclaimer.
+//     * Redistributions in binary form must reproduce the above
+// copyright notice, this list of conditions and the following disclaimer
+// in the documentation and/or other materials provided with the
+// distribution.
+//     * Neither the name of Google Inc. nor the names of its
+// contributors may be used to endorse or promote products derived from
+// this software without specific prior written permission.
+//
+// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
+// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
+// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
+// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
+// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
+// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
+// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
+// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
+// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
+//
 // Author: Craig Silverstein
 //
 // Produce stack trace.  I'm guessing (hoping!) the code is much like
@@ -101,82 +127,4 @@ int GetStackTrace(void** result, int max_depth, int skip_count) {
   return n;
 }
 
-// If you change this function, also change GetStackTrace above:
-//
-// This GetStackFrames routine shares a lot of code with GetStackTrace
-// above. This code could have been refactored into a common routine,
-// and then both GetStackTrace/GetStackFrames could call that routine.
-// There are two problems with that:
-//
-// (1) The performance of the refactored-code suffers substantially - the
-//     refactored needs to be able to record the stack trace when called
-//     from GetStackTrace, and both the stack trace and stack frame sizes,
-//     when called from GetStackFrames - this introduces enough new
-//     conditionals that GetStackTrace performance can degrade by as much
-//     as 50%.
-//
-// (2) Whether the refactored routine gets inlined into GetStackTrace and
-//     GetStackFrames depends on the compiler, and we can't guarantee the
-//     behavior either-way, even with "__attribute__ ((always_inline))"
-//     or "__attribute__ ((noinline))". But we need this guarantee or the
-//     frame counts may be off by one.
-//
-// Both (1) and (2) can be addressed without this code duplication, by
-// clever use of template functions, and by defining GetStackTrace and
-// GetStackFrames as macros that expand to these template functions.
-// However, this approach comes with its own set of problems - namely,
-// macros and  preprocessor trouble - for example,  if GetStackTrace
-// and/or GetStackFrames is ever defined as a member functions in some
-// class, we are in trouble.
-int GetStackFrames(void** pcs, int *sizes, int max_depth, int skip_count) {
-  void **sp;
-#ifdef __APPLE__
-  __asm__ volatile ("mr %0,r1" : "=r" (sp));
-#else
-  __asm__ volatile ("mr %0,1" : "=r" (sp));
-#endif
-
-  StacktracePowerPCDummyFunction();
-  // Note we do *not* increment skip_count here for the SYSV ABI.  If
-  // we did, the list of stack frames wouldn't properly match up with
-  // the list of return addresses.  Note this means the top pc entry
-  // is probably bogus for linux/ppc (and other SYSV-ABI systems).
-
-  int n = 0;
-  while (sp && n < max_depth) {
-    // The GetStackFrames routine is called when we are in some
-    // informational context (the failure signal handler for example).
-    // Use the non-strict unwinding rules to produce a stack trace
-    // that is as complete as possible (even if it contains a few bogus
-    // entries in some rare cases).
-    void **next_sp = NextStackFrame<false>(sp);
-    if (skip_count > 0) {
-      skip_count--;
-    } else {
-#if defined(_CALL_AIX) || defined(_CALL_DARWIN)
-      pcs[n++] = *(sp+2);
-#elif defined(_CALL_SYSV)
-      pcs[n++] = *(sp+1);
-#elif defined(__APPLE__) || (defined(__linux) && defined(__PPC64__))
-      // This check is in case the compiler doesn't define _CALL_AIX/etc.
-      pcs[n++] = *(sp+2);
-#elif defined(__linux)
-      // This check is in case the compiler doesn't define _CALL_SYSV.
-      pcs[n++] = *(sp+1);
-#else
-#error Need to specify the PPC ABI for your archiecture.
-#endif
-      if (next_sp > sp) {
-        sizes[n] = (uintptr_t)next_sp - (uintptr_t)sp;
-      } else {
-        // A frame-size of 0 is used to indicate unknown frame size.
-        sizes[n] = 0;
-      }
-      n++;
-    }
-    sp = next_sp;
-  }
-  return n;
-}
-
 _END_GOOGLE_NAMESPACE_