Moving BeefMem

BeefTools/BeefMem/gperftools/src/stacktrace_powerpc-inl.h

@@ -0,0 +1,169 @@
+// 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
+// for x86.  For apple machines, at least, it seems to be; see
+//    http://developer.apple.com/documentation/mac/runtimehtml/RTArch-59.html
+//    http://www.linux-foundation.org/spec/ELF/ppc64/PPC-elf64abi-1.9.html#STACK
+// Linux has similar code: http://patchwork.ozlabs.org/linuxppc/patch?id=8882
+
+#ifndef BASE_STACKTRACE_POWERPC_INL_H_
+#define BASE_STACKTRACE_POWERPC_INL_H_
+// Note: this file is included into stacktrace.cc more than once.
+// Anything that should only be defined once should be here:
+
+#include <stdint.h>   // for uintptr_t
+#include <stdlib.h>   // for NULL
+#include <gperftools/stacktrace.h>
+
+struct layout_ppc {
+  struct layout_ppc *next;
+#if defined(__APPLE__) || (defined(__linux) && defined(__PPC64__))
+  long condition_register;
+#endif
+  void *return_addr;
+};
+
+// Given a pointer to a stack frame, locate and return the calling
+// stackframe, or return NULL if no stackframe can be found. Perform sanity
+// checks (the strictness of which is controlled by the boolean parameter
+// "STRICT_UNWINDING") to reduce the chance that a bad pointer is returned.
+template<bool STRICT_UNWINDING>
+static layout_ppc *NextStackFrame(layout_ppc *current) {
+  uintptr_t old_sp = (uintptr_t)(current);
+  uintptr_t new_sp = (uintptr_t)(current->next);
+
+  // Check that the transition from frame pointer old_sp to frame
+  // pointer new_sp isn't clearly bogus
+  if (STRICT_UNWINDING) {
+    // With the stack growing downwards, older stack frame must be
+    // at a greater address that the current one.
+    if (new_sp <= old_sp)
+      return NULL;
+    // Assume stack frames larger than 100,000 bytes are bogus.
+    if (new_sp - old_sp > 100000)
+      return NULL;
+  } else {
+    // In the non-strict mode, allow discontiguous stack frames.
+    // (alternate-signal-stacks for example).
+    if (new_sp == old_sp)
+      return NULL;
+    // And allow frames upto about 1MB.
+    if ((new_sp > old_sp) && (new_sp - old_sp > 1000000))
+      return NULL;
+  }
+  if (new_sp & (sizeof(void *) - 1))
+    return NULL;
+  return current->next;
+}
+
+// This ensures that GetStackTrace stes up the Link Register properly.
+void StacktracePowerPCDummyFunction() __attribute__((noinline));
+void StacktracePowerPCDummyFunction() { __asm__ volatile(""); }
+#endif  // BASE_STACKTRACE_POWERPC_INL_H_
+
+// Note: this part of the file is included several times.
+// Do not put globals below.
+
+// Load instruction used on top-of-stack get.
+#if defined(__PPC64__) || defined(__LP64__)
+# define LOAD "ld"
+#else
+# define LOAD "lwz"
+#endif
+
+#if defined(__linux__) && defined(__PPC__)
+# define TOP_STACK "%0,0(1)"
+#elif defined(__MACH__) && defined(__APPLE__)
+// Apple OS X uses an old version of gnu as -- both Darwin 7.9.0 (Panther)
+// and Darwin 8.8.1 (Tiger) use as 1.38.  This means we have to use a
+// different asm syntax.  I don't know quite the best way to discriminate
+// systems using the old as from the new one; I've gone with __APPLE__.
+// TODO(csilvers): use autoconf instead, to look for 'as --version' == 1 or 2
+# define TOP_STACK "%0,0(r1)"
+#endif
+
+
+
+// The following 4 functions are generated from the code below:
+//   GetStack{Trace,Frames}()
+//   GetStack{Trace,Frames}WithContext()
+//
+// These functions take the following args:
+//   void** result: the stack-trace, as an array
+//   int* sizes: the size of each stack frame, as an array
+//               (GetStackFrames* only)
+//   int max_depth: the size of the result (and sizes) array(s)
+//   int skip_count: how many stack pointers to skip before storing in result
+//   void* ucp: a ucontext_t* (GetStack{Trace,Frames}WithContext only)
+int GET_STACK_TRACE_OR_FRAMES {
+  layout_ppc *current;
+  int n;
+
+  // Force GCC to spill LR.
+  asm volatile ("" : "=l"(current));
+
+  // Get the address on top-of-stack
+  asm volatile (LOAD " " TOP_STACK : "=r"(current));
+
+  StacktracePowerPCDummyFunction();
+
+  n = 0;
+  while (current && n < max_depth) {
+    result[n] = current->return_addr;
+
+    // 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).
+    layout_ppc *next = NextStackFrame<!IS_STACK_FRAMES>(current);
+#if IS_STACK_FRAMES
+    if (next > current) {
+      sizes[n] = (uintptr_t)next - (uintptr_t)current;
+    } else {
+      // A frame-size of 0 is used to indicate unknown frame size.
+      sizes[n] = 0;
+    }
+#endif
+    current = next;
+    n++;
+  }
+
+  // It's possible the second-last stack frame can't return
+  // (that is, it's __libc_start_main), in which case
+  // the CRT startup code will have set its LR to 'NULL'.
+  if (n > 0 && result[n-1] == NULL)
+    n--;
+
+  return n;
+}