diff options
author | Dawid Potocki <dawid@dawidpotocki.com> | 2024-03-05 14:09:27 +1300 |
---|---|---|
committer | Dawid Potocki <dawid@dawidpotocki.com> | 2024-03-05 20:34:15 +1300 |
commit | 063e15900bda8453fb0fc6751e78d064501ccbae (patch) | |
tree | a4cd5f01dbca33a262333aff10e1e035217a30c8 /externals/breakpad/src/processor/stackwalker_selftest.cc | |
parent | 537296095ab24eddcb196b5ef98004f91de9c8c2 (diff) |
Diffstat (limited to 'externals/breakpad/src/processor/stackwalker_selftest.cc')
-rw-r--r-- | externals/breakpad/src/processor/stackwalker_selftest.cc | 436 |
1 files changed, 436 insertions, 0 deletions
diff --git a/externals/breakpad/src/processor/stackwalker_selftest.cc b/externals/breakpad/src/processor/stackwalker_selftest.cc new file mode 100644 index 0000000000..4f3483b417 --- /dev/null +++ b/externals/breakpad/src/processor/stackwalker_selftest.cc @@ -0,0 +1,436 @@ +// Copyright 2006 Google LLC +// +// 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 LLC 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. + +// stackwalker_selftest.cc: Tests StackwalkerX86 or StackwalkerPPC using the +// running process' stack as test data, if running on an x86 or ppc and +// compiled with gcc. This test is not enabled in the "make check" suite +// by default, because certain optimizations interfere with its proper +// operation. To turn it on, configure with --enable-selftest. +// +// Optimizations that cause problems: +// - stack frame reuse. The Recursor function here calls itself with +// |return Recursor|. When the caller's frame is reused, it will cause +// CountCallerFrames to correctly return the same number of frames +// in both the caller and callee. This is considered an unexpected +// condition in the test, which expects a callee to have one more +// caller frame in the stack than its caller. +// - frame pointer omission. Even with a stackwalker that understands +// this optimization, the code to harness debug information currently +// only exists to retrieve it from minidumps, not the current process. +// +// This test can also serve as a developmental and debugging aid if +// PRINT_STACKS is defined. +// +// Author: Mark Mentovai + +#ifdef HAVE_CONFIG_H +#include <config.h> // Must come first +#endif + +#include <assert.h> + +#include "processor/logging.h" + +#if defined(__i386) && !defined(__i386__) +#define __i386__ +#endif +#if defined(__sparc) && !defined(__sparc__) +#define __sparc__ +#endif + +#if (defined(__SUNPRO_CC) || defined(__GNUC__)) && \ + (defined(__i386__) || defined(__ppc__) || defined(__sparc__)) + + +#include <stdio.h> + +#include "common/scoped_ptr.h" +#include "google_breakpad/common/breakpad_types.h" +#include "google_breakpad/common/minidump_format.h" +#include "google_breakpad/processor/basic_source_line_resolver.h" +#include "google_breakpad/processor/call_stack.h" +#include "google_breakpad/processor/code_module.h" +#include "google_breakpad/processor/memory_region.h" +#include "google_breakpad/processor/stack_frame.h" +#include "google_breakpad/processor/stack_frame_cpu.h" + +using google_breakpad::BasicSourceLineResolver; +using google_breakpad::CallStack; +using google_breakpad::CodeModule; +using google_breakpad::MemoryRegion; +using google_breakpad::scoped_ptr; +using google_breakpad::StackFrame; +using google_breakpad::StackFramePPC; +using google_breakpad::StackFrameX86; +using google_breakpad::StackFrameSPARC; + +#if defined(__i386__) +#include "processor/stackwalker_x86.h" +using google_breakpad::StackwalkerX86; +#elif defined(__ppc__) +#include "processor/stackwalker_ppc.h" +using google_breakpad::StackwalkerPPC; +#elif defined(__sparc__) +#include "processor/stackwalker_sparc.h" +using google_breakpad::StackwalkerSPARC; +#endif // __i386__ || __ppc__ || __sparc__ + +#define RECURSION_DEPTH 100 + + +// A simple MemoryRegion subclass that provides direct access to this +// process' memory space by pointer. +class SelfMemoryRegion : public MemoryRegion { + public: + virtual uint64_t GetBase() const { return 0; } + virtual uint32_t GetSize() const { return 0xffffffff; } + + bool GetMemoryAtAddress(uint64_t address, uint8_t* value) const { + return GetMemoryAtAddressInternal(address, value); } + bool GetMemoryAtAddress(uint64_t address, uint16_t* value) const { + return GetMemoryAtAddressInternal(address, value); } + bool GetMemoryAtAddress(uint64_t address, uint32_t* value) const { + return GetMemoryAtAddressInternal(address, value); } + bool GetMemoryAtAddress(uint64_t address, uint64_t* value) const { + return GetMemoryAtAddressInternal(address, value); } + void Print() const { + assert(false); + } + + private: + template<typename T> bool GetMemoryAtAddressInternal(uint64_t address, + T* value) { + // Without knowing what addresses are actually mapped, just assume that + // everything low is not mapped. This helps the stackwalker catch the + // end of a stack when it tries to dereference a null or low pointer + // in an attempt to find the caller frame. Other unmapped accesses will + // cause the program to crash, but that would properly be a test failure. + if (address < 0x100) + return false; + + uint8_t* memory = 0; + *value = *reinterpret_cast<const T*>(&memory[address]); + return true; + } +}; + + +#if defined(__GNUC__) + + +#if defined(__i386__) + +// GetEBP returns the current value of the %ebp register. Because it's +// implemented as a function, %ebp itself contains GetEBP's frame pointer +// and not the caller's frame pointer. Dereference %ebp to obtain the +// caller's frame pointer, which the compiler-generated preamble stored +// on the stack (provided frame pointers are not being omitted.) Because +// this function depends on the compiler-generated preamble, inlining is +// disabled. +static uint32_t GetEBP() __attribute__((noinline)); +static uint32_t GetEBP() { + uint32_t ebp; + __asm__ __volatile__( + "movl (%%ebp), %0" + : "=a" (ebp) + ); + return ebp; +} + + +// The caller's %esp is 8 higher than the value of %ebp in this function, +// assuming that it's not inlined and that the standard prolog is used. +// The CALL instruction places a 4-byte return address on the stack above +// the caller's %esp, and this function's prolog will save the caller's %ebp +// on the stack as well, for another 4 bytes, before storing %esp in %ebp. +static uint32_t GetESP() __attribute__((noinline)); +static uint32_t GetESP() { + uint32_t ebp; + __asm__ __volatile__( + "movl %%ebp, %0" + : "=a" (ebp) + ); + return ebp + 8; +} + + +// GetEIP returns the instruction pointer identifying the next instruction +// to execute after GetEIP returns. It obtains this information from the +// stack, where it was placed by the call instruction that called GetEIP. +// This function depends on frame pointers not being omitted. It is possible +// to write a pure asm version of this routine that has no compiler-generated +// preamble and uses %esp instead of %ebp; that would function in the +// absence of frame pointers. However, the simpler approach is used here +// because GetEBP and stackwalking necessarily depends on access to frame +// pointers. Because this function depends on a call instruction and the +// compiler-generated preamble, inlining is disabled. +static uint32_t GetEIP() __attribute__((noinline)); +static uint32_t GetEIP() { + uint32_t eip; + __asm__ __volatile__( + "movl 4(%%ebp), %0" + : "=a" (eip) + ); + return eip; +} + + +#elif defined(__ppc__) + + +// GetSP returns the current value of the %r1 register, which by convention, +// is the stack pointer on ppc. Because it's implemented as a function, +// %r1 itself contains GetSP's own stack pointer and not the caller's stack +// pointer. Dereference %r1 to obtain the caller's stack pointer, which the +// compiler-generated prolog stored on the stack. Because this function +// depends on the compiler-generated prolog, inlining is disabled. +static uint32_t GetSP() __attribute__((noinline)); +static uint32_t GetSP() { + uint32_t sp; + __asm__ __volatile__( + "lwz %0, 0(r1)" + : "=r" (sp) + ); + return sp; +} + + +// GetPC returns the program counter identifying the next instruction to +// execute after GetPC returns. It obtains this information from the +// link register, where it was placed by the branch instruction that called +// GetPC. Because this function depends on the caller's use of a branch +// instruction, inlining is disabled. +static uint32_t GetPC() __attribute__((noinline)); +static uint32_t GetPC() { + uint32_t lr; + __asm__ __volatile__( + "mflr %0" + : "=r" (lr) + ); + return lr; +} + + +#elif defined(__sparc__) + + +// GetSP returns the current value of the %sp/%o6/%g_r[14] register, which +// by convention, is the stack pointer on sparc. Because it's implemented +// as a function, %sp itself contains GetSP's own stack pointer and not +// the caller's stack pointer. Dereference to obtain the caller's stack +// pointer, which the compiler-generated prolog stored on the stack. +// Because this function depends on the compiler-generated prolog, inlining +// is disabled. +static uint32_t GetSP() __attribute__((noinline)); +static uint32_t GetSP() { + uint32_t sp; + __asm__ __volatile__( + "mov %%fp, %0" + : "=r" (sp) + ); + return sp; +} + +// GetFP returns the current value of the %fp register. Because it's +// implemented as a function, %fp itself contains GetFP's frame pointer +// and not the caller's frame pointer. Dereference %fp to obtain the +// caller's frame pointer, which the compiler-generated preamble stored +// on the stack (provided frame pointers are not being omitted.) Because +// this function depends on the compiler-generated preamble, inlining is +// disabled. +static uint32_t GetFP() __attribute__((noinline)); +static uint32_t GetFP() { + uint32_t fp; + __asm__ __volatile__( + "ld [%%fp+56], %0" + : "=r" (fp) + ); + return fp; +} + +// GetPC returns the program counter identifying the next instruction to +// execute after GetPC returns. It obtains this information from the +// link register, where it was placed by the branch instruction that called +// GetPC. Because this function depends on the caller's use of a branch +// instruction, inlining is disabled. +static uint32_t GetPC() __attribute__((noinline)); +static uint32_t GetPC() { + uint32_t pc; + __asm__ __volatile__( + "mov %%i7, %0" + : "=r" (pc) + ); + return pc + 8; +} + +#endif // __i386__ || __ppc__ || __sparc__ + +#elif defined(__SUNPRO_CC) + +#if defined(__i386__) +extern "C" { +extern uint32_t GetEIP(); +extern uint32_t GetEBP(); +extern uint32_t GetESP(); +} +#elif defined(__sparc__) +extern "C" { +extern uint32_t GetPC(); +extern uint32_t GetFP(); +extern uint32_t GetSP(); +} +#endif // __i386__ || __sparc__ + +#endif // __GNUC__ || __SUNPRO_CC + +// CountCallerFrames returns the number of stack frames beneath the function +// that called CountCallerFrames. Because this function's return value +// is dependent on the size of the stack beneath it, inlining is disabled, +// and any function that calls this should not be inlined either. +#if defined(__GNUC__) +static unsigned int CountCallerFrames() __attribute__((noinline)); +#elif defined(__SUNPRO_CC) +static unsigned int CountCallerFrames(); +#endif +static unsigned int CountCallerFrames() { + SelfMemoryRegion memory; + BasicSourceLineResolver resolver; + +#if defined(__i386__) + MDRawContextX86 context = MDRawContextX86(); + context.eip = GetEIP(); + context.ebp = GetEBP(); + context.esp = GetESP(); + + StackwalkerX86 stackwalker = StackwalkerX86(NULL, &context, &memory, NULL, + NULL, &resolver); +#elif defined(__ppc__) + MDRawContextPPC context = MDRawContextPPC(); + context.srr0 = GetPC(); + context.gpr[1] = GetSP(); + + StackwalkerPPC stackwalker = StackwalkerPPC(NULL, &context, &memory, NULL, + NULL, &resolver); +#elif defined(__sparc__) + MDRawContextSPARC context = MDRawContextSPARC(); + context.pc = GetPC(); + context.g_r[14] = GetSP(); + context.g_r[30] = GetFP(); + + StackwalkerSPARC stackwalker = StackwalkerSPARC(NULL, &context, &memory, + NULL, NULL, &resolver); +#endif // __i386__ || __ppc__ || __sparc__ + + CallStack stack; + vector<const CodeModule*> modules_without_symbols; + stackwalker.Walk(&stack, &modules_without_symbols); + +#ifdef PRINT_STACKS + printf("\n"); + for (unsigned int frame_index = 0; + frame_index < stack.frames()->size(); + ++frame_index) { + StackFrame *frame = stack.frames()->at(frame_index); + printf("frame %-3d instruction = 0x%08" PRIx64, + frame_index, frame->instruction); +#if defined(__i386__) + StackFrameX86 *frame_x86 = reinterpret_cast<StackFrameX86*>(frame); + printf(" esp = 0x%08x ebp = 0x%08x\n", + frame_x86->context.esp, frame_x86->context.ebp); +#elif defined(__ppc__) + StackFramePPC *frame_ppc = reinterpret_cast<StackFramePPC*>(frame); + printf(" gpr[1] = 0x%08x\n", frame_ppc->context.gpr[1]); +#elif defined(__sparc__) + StackFrameSPARC *frame_sparc = reinterpret_cast<StackFrameSPARC*>(frame); + printf(" sp = 0x%08x fp = 0x%08x\n", + frame_sparc->context.g_r[14], frame_sparc->context.g_r[30]); +#endif // __i386__ || __ppc__ || __sparc__ + } +#endif // PRINT_STACKS + + // Subtract 1 because the caller wants the number of frames beneath + // itself. Because the caller called us, subract two for our frame and its + // frame, which are included in stack.size(). + return stack.frames()->size() - 2; +} + + +// Recursor verifies that the number stack frames beneath itself is one more +// than the number of stack frames beneath its parent. When depth frames +// have been reached, Recursor stops checking and returns success. If the +// frame count check fails at any depth, Recursor will stop and return false. +// Because this calls CountCallerFrames, inlining is disabled. +#if defined(__GNUC__) +static bool Recursor(unsigned int depth, unsigned int parent_callers) + __attribute__((noinline)); +#elif defined(__SUNPRO_CC) +static bool Recursor(unsigned int depth, unsigned int parent_callers); +#endif +static bool Recursor(unsigned int depth, unsigned int parent_callers) { + unsigned int callers = CountCallerFrames(); + if (callers != parent_callers + 1) + return false; + + if (depth) + return Recursor(depth - 1, callers); + + // depth == 0 + return true; +} + + +// Because this calls CountCallerFrames, inlining is disabled - but because +// it's main (and nobody calls it other than the entry point), it wouldn't +// be inlined anyway. +#if defined(__GNUC__) +int main(int argc, char** argv) __attribute__((noinline)); +#elif defined(__SUNPRO_CC) +int main(int argc, char** argv); +#endif +int main(int argc, char** argv) { + BPLOG_INIT(&argc, &argv); + + return Recursor(RECURSION_DEPTH, CountCallerFrames()) ? 0 : 1; +} + + +#else +// Not i386 or ppc or sparc? We can only test stacks we know how to walk. + + +int main(int argc, char** argv) { + BPLOG_INIT(&argc, &argv); + + // "make check" interprets an exit status of 77 to mean that the test is + // not supported. + BPLOG(ERROR) << "Selftest not supported here"; + return 77; +} + + +#endif // (__GNUC__ || __SUNPRO_CC) && (__i386__ || __ppc__ || __sparc__) |