michael@0: // Copyright (c) 2010 Google Inc.
michael@0: // All rights reserved.
michael@0: //
michael@0: // Redistribution and use in source and binary forms, with or without
michael@0: // modification, are permitted provided that the following conditions are
michael@0: // met:
michael@0: //
michael@0: //     * Redistributions of source code must retain the above copyright
michael@0: // notice, this list of conditions and the following disclaimer.
michael@0: //     * Redistributions in binary form must reproduce the above
michael@0: // copyright notice, this list of conditions and the following disclaimer
michael@0: // in the documentation and/or other materials provided with the
michael@0: // distribution.
michael@0: //     * Neither the name of Google Inc. nor the names of its
michael@0: // contributors may be used to endorse or promote products derived from
michael@0: // this software without specific prior written permission.
michael@0: //
michael@0: // THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
michael@0: // "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
michael@0: // LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
michael@0: // A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
michael@0: // OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
michael@0: // SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
michael@0: // LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
michael@0: // DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
michael@0: // THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
michael@0: // (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
michael@0: // OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
michael@0: 
michael@0: // stackwalker_sparc.cc: sparc-specific stackwalker.
michael@0: //
michael@0: // See stackwalker_sparc.h for documentation.
michael@0: //
michael@0: // Author: Michael Shang
michael@0: 
michael@0: 
michael@0: #include "google_breakpad/processor/call_stack.h"
michael@0: #include "google_breakpad/processor/memory_region.h"
michael@0: #include "google_breakpad/processor/stack_frame_cpu.h"
michael@0: #include "common/logging.h"
michael@0: #include "processor/stackwalker_sparc.h"
michael@0: 
michael@0: namespace google_breakpad {
michael@0: 
michael@0: 
michael@0: StackwalkerSPARC::StackwalkerSPARC(const SystemInfo* system_info,
michael@0:                                    const MDRawContextSPARC* context,
michael@0:                                    MemoryRegion* memory,
michael@0:                                    const CodeModules* modules,
michael@0:                                    StackFrameSymbolizer* resolver_helper)
michael@0:     : Stackwalker(system_info, memory, modules, resolver_helper),
michael@0:       context_(context) {
michael@0: }
michael@0: 
michael@0: 
michael@0: StackFrame* StackwalkerSPARC::GetContextFrame() {
michael@0:   if (!context_) {
michael@0:     BPLOG(ERROR) << "Can't get context frame without context";
michael@0:     return NULL;
michael@0:   }
michael@0: 
michael@0:   StackFrameSPARC* frame = new StackFrameSPARC();
michael@0: 
michael@0:   // The instruction pointer is stored directly in a register, so pull it
michael@0:   // straight out of the CPU context structure.
michael@0:   frame->context = *context_;
michael@0:   frame->context_validity = StackFrameSPARC::CONTEXT_VALID_ALL;
michael@0:   frame->trust = StackFrame::FRAME_TRUST_CONTEXT;
michael@0:   frame->instruction = frame->context.pc;
michael@0: 
michael@0:   return frame;
michael@0: }
michael@0: 
michael@0: 
michael@0: StackFrame* StackwalkerSPARC::GetCallerFrame(const CallStack* stack,
michael@0:                                              bool stack_scan_allowed) {
michael@0:   if (!memory_ || !stack) {
michael@0:     BPLOG(ERROR) << "Can't get caller frame without memory or stack";
michael@0:     return NULL;
michael@0:   }
michael@0: 
michael@0:   StackFrameSPARC* last_frame = static_cast<StackFrameSPARC*>(
michael@0:       stack->frames()->back());
michael@0: 
michael@0:   // new: caller
michael@0:   // old: callee
michael@0:   // %fp, %i6 and g_r[30] is the same, see minidump_format.h
michael@0:   // %sp, %o6 and g_r[14] is the same, see minidump_format.h
michael@0:   // %sp_new = %fp_old
michael@0:   // %fp_new = *(%fp_old + 32 + 32 - 8), where the callee's %i6
michael@0:   // %pc_new = *(%fp_old + 32 + 32 - 4) + 8
michael@0:   // which is callee's %i7 plus 8
michael@0: 
michael@0:   // A caller frame must reside higher in memory than its callee frames.
michael@0:   // Anything else is an error, or an indication that we've reached the
michael@0:   // end of the stack.
michael@0:   uint64_t stack_pointer = last_frame->context.g_r[30];
michael@0:   if (stack_pointer <= last_frame->context.g_r[14]) {
michael@0:     return NULL;
michael@0:   }
michael@0: 
michael@0:   uint32_t instruction;
michael@0:   if (!memory_->GetMemoryAtAddress(stack_pointer + 60,
michael@0:                      &instruction) || instruction <= 1) {
michael@0:     return NULL;
michael@0:   }
michael@0: 
michael@0:   uint32_t stack_base;
michael@0:   if (!memory_->GetMemoryAtAddress(stack_pointer + 56,
michael@0:                      &stack_base) || stack_base <= 1) {
michael@0:     return NULL;
michael@0:   }
michael@0: 
michael@0:   StackFrameSPARC* frame = new StackFrameSPARC();
michael@0: 
michael@0:   frame->context = last_frame->context;
michael@0:   frame->context.g_r[14] = stack_pointer;
michael@0:   frame->context.g_r[30] = stack_base;
michael@0: 
michael@0:   // frame->context.pc is the return address, which is 2 instruction
michael@0:   // past the branch that caused us to arrive at the callee, which are
michael@0:   // a CALL instruction then a NOP instruction.
michael@0:   // frame_ppc->instruction to 8 less than that.  Since all sparc
michael@0:   // instructions are 4 bytes wide, this is the address of the branch
michael@0:   // instruction.  This allows source line information to match up with the
michael@0:   // line that contains a function call.  Callers that require the exact
michael@0:   // return address value may access the %i7/g_r[31] field of StackFrameSPARC.
michael@0:   frame->context.pc = instruction + 8;
michael@0:   frame->instruction = instruction;
michael@0:   frame->context_validity = StackFrameSPARC::CONTEXT_VALID_PC |
michael@0:                             StackFrameSPARC::CONTEXT_VALID_SP |
michael@0:                             StackFrameSPARC::CONTEXT_VALID_FP;
michael@0:   frame->trust = StackFrame::FRAME_TRUST_FP;
michael@0: 
michael@0:   return frame;
michael@0: }
michael@0: 
michael@0: 
michael@0: }  // namespace google_breakpad