1.1 --- /dev/null Thu Jan 01 00:00:00 1970 +0000
1.2 +++ b/toolkit/crashreporter/google-breakpad/src/processor/stackwalker_ppc.cc Wed Dec 31 06:09:35 2014 +0100
1.3 @@ -0,0 +1,146 @@
1.4 +// Copyright (c) 2010 Google Inc.
1.5 +// All rights reserved.
1.6 +//
1.7 +// Redistribution and use in source and binary forms, with or without
1.8 +// modification, are permitted provided that the following conditions are
1.9 +// met:
1.10 +//
1.11 +// * Redistributions of source code must retain the above copyright
1.12 +// notice, this list of conditions and the following disclaimer.
1.13 +// * Redistributions in binary form must reproduce the above
1.14 +// copyright notice, this list of conditions and the following disclaimer
1.15 +// in the documentation and/or other materials provided with the
1.16 +// distribution.
1.17 +// * Neither the name of Google Inc. nor the names of its
1.18 +// contributors may be used to endorse or promote products derived from
1.19 +// this software without specific prior written permission.
1.20 +//
1.21 +// THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
1.22 +// "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
1.23 +// LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
1.24 +// A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
1.25 +// OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
1.26 +// SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
1.27 +// LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
1.28 +// DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
1.29 +// THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
1.30 +// (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
1.31 +// OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
1.32 +
1.33 +// stackwalker_ppc.cc: ppc-specific stackwalker.
1.34 +//
1.35 +// See stackwalker_ppc.h for documentation.
1.36 +//
1.37 +// Author: Mark Mentovai
1.38 +
1.39 +
1.40 +#include "processor/stackwalker_ppc.h"
1.41 +#include "google_breakpad/processor/call_stack.h"
1.42 +#include "google_breakpad/processor/memory_region.h"
1.43 +#include "google_breakpad/processor/stack_frame_cpu.h"
1.44 +#include "common/logging.h"
1.45 +
1.46 +namespace google_breakpad {
1.47 +
1.48 +
1.49 +StackwalkerPPC::StackwalkerPPC(const SystemInfo* system_info,
1.50 + const MDRawContextPPC* context,
1.51 + MemoryRegion* memory,
1.52 + const CodeModules* modules,
1.53 + StackFrameSymbolizer* resolver_helper)
1.54 + : Stackwalker(system_info, memory, modules, resolver_helper),
1.55 + context_(context) {
1.56 + if (memory_ && memory_->GetBase() + memory_->GetSize() - 1 > 0xffffffff) {
1.57 + // This implementation only covers 32-bit ppc CPUs. The limits of the
1.58 + // supplied stack are invalid. Mark memory_ = NULL, which will cause
1.59 + // stackwalking to fail.
1.60 + BPLOG(ERROR) << "Memory out of range for stackwalking: " <<
1.61 + HexString(memory_->GetBase()) << "+" <<
1.62 + HexString(memory_->GetSize());
1.63 + memory_ = NULL;
1.64 + }
1.65 +}
1.66 +
1.67 +
1.68 +StackFrame* StackwalkerPPC::GetContextFrame() {
1.69 + if (!context_) {
1.70 + BPLOG(ERROR) << "Can't get context frame without context";
1.71 + return NULL;
1.72 + }
1.73 +
1.74 + StackFramePPC* frame = new StackFramePPC();
1.75 +
1.76 + // The instruction pointer is stored directly in a register, so pull it
1.77 + // straight out of the CPU context structure.
1.78 + frame->context = *context_;
1.79 + frame->context_validity = StackFramePPC::CONTEXT_VALID_ALL;
1.80 + frame->trust = StackFrame::FRAME_TRUST_CONTEXT;
1.81 + frame->instruction = frame->context.srr0;
1.82 +
1.83 + return frame;
1.84 +}
1.85 +
1.86 +
1.87 +StackFrame* StackwalkerPPC::GetCallerFrame(const CallStack* stack,
1.88 + bool stack_scan_allowed) {
1.89 + if (!memory_ || !stack) {
1.90 + BPLOG(ERROR) << "Can't get caller frame without memory or stack";
1.91 + return NULL;
1.92 + }
1.93 +
1.94 + // The instruction pointers for previous frames are saved on the stack.
1.95 + // The typical ppc calling convention is for the called procedure to store
1.96 + // its return address in the calling procedure's stack frame at 8(%r1),
1.97 + // and to allocate its own stack frame by decrementing %r1 (the stack
1.98 + // pointer) and saving the old value of %r1 at 0(%r1). Because the ppc has
1.99 + // no hardware stack, there is no distinction between the stack pointer and
1.100 + // frame pointer, and what is typically thought of as the frame pointer on
1.101 + // an x86 is usually referred to as the stack pointer on a ppc.
1.102 +
1.103 + StackFramePPC* last_frame = static_cast<StackFramePPC*>(
1.104 + stack->frames()->back());
1.105 +
1.106 + // A caller frame must reside higher in memory than its callee frames.
1.107 + // Anything else is an error, or an indication that we've reached the
1.108 + // end of the stack.
1.109 + uint32_t stack_pointer;
1.110 + if (!memory_->GetMemoryAtAddress(last_frame->context.gpr[1],
1.111 + &stack_pointer) ||
1.112 + stack_pointer <= last_frame->context.gpr[1]) {
1.113 + return NULL;
1.114 + }
1.115 +
1.116 + // Mac OS X/Darwin gives 1 as the return address from the bottom-most
1.117 + // frame in a stack (a thread's entry point). I haven't found any
1.118 + // documentation on this, but 0 or 1 would be bogus return addresses,
1.119 + // so check for them here and return false (end of stack) when they're
1.120 + // hit to avoid having a phantom frame.
1.121 + uint32_t instruction;
1.122 + if (!memory_->GetMemoryAtAddress(stack_pointer + 8, &instruction) ||
1.123 + instruction <= 1) {
1.124 + return NULL;
1.125 + }
1.126 +
1.127 + StackFramePPC* frame = new StackFramePPC();
1.128 +
1.129 + frame->context = last_frame->context;
1.130 + frame->context.srr0 = instruction;
1.131 + frame->context.gpr[1] = stack_pointer;
1.132 + frame->context_validity = StackFramePPC::CONTEXT_VALID_SRR0 |
1.133 + StackFramePPC::CONTEXT_VALID_GPR1;
1.134 + frame->trust = StackFrame::FRAME_TRUST_FP;
1.135 +
1.136 + // frame->context.srr0 is the return address, which is one instruction
1.137 + // past the branch that caused us to arrive at the callee. Set
1.138 + // frame_ppc->instruction to four less than that. Since all ppc
1.139 + // instructions are 4 bytes wide, this is the address of the branch
1.140 + // instruction. This allows source line information to match up with the
1.141 + // line that contains a function call. Callers that require the exact
1.142 + // return address value may access the context.srr0 field of StackFramePPC.
1.143 + frame->instruction = frame->context.srr0 - 4;
1.144 +
1.145 + return frame;
1.146 +}
1.147 +
1.148 +
1.149 +} // namespace google_breakpad
