// stack trace helper
static ProfileStackTrace getStackTrace() {
ProfileStackTrace trace;
if (g_context.isNull()) return trace;
VMRegAnchor _;
ActRec *fp = vmfp();
if (!fp) return trace;
PC pc = vmpc();
const Func *f = fp->m_func;
Unit *u = f->unit();
Offset off = pc - u->entry();
for (;;) {
trace.push_back({ f, off, fp->resumed() });
fp = g_context->getPrevVMStateUNSAFE(fp, &off);
if (!fp) break;
f = fp->m_func;
}
return trace;
}
Array createBacktrace(const BacktraceArgs& btArgs) {
Array bt = Array::Create();
// If there is a parser frame, put it at the beginning of
// the backtrace
if (btArgs.m_parserFrame) {
bt.append(
make_map_array(
s_file, btArgs.m_parserFrame->filename,
s_line, btArgs.m_parserFrame->lineNumber
)
);
}
VMRegAnchor _;
if (!vmfp()) {
// If there are no VM frames, we're done
return bt;
}
int depth = 0;
ActRec* fp = nullptr;
Offset pc = 0;
// Get the fp and pc of the top frame (possibly skipping one frame)
{
if (btArgs.m_skipTop) {
fp = g_context->getPrevVMState(vmfp(), &pc);
if (!fp) {
// We skipped over the only VM frame, we're done
return bt;
}
} else {
fp = vmfp();
Unit *unit = vmfp()->m_func->unit();
assert(unit);
pc = unit->offsetOf(vmpc());
}
// Handle the top frame
if (btArgs.m_withSelf) {
// Builtins don't have a file and line number
if (!fp->m_func->isBuiltin()) {
Unit* unit = fp->m_func->unit();
assert(unit);
const char* filename = fp->m_func->filename()->data();
Offset off = pc;
ArrayInit frame(btArgs.m_parserFrame ? 4 : 2, ArrayInit::Map{});
frame.set(s_file, filename);
frame.set(s_line, unit->getLineNumber(off));
if (btArgs.m_parserFrame) {
frame.set(s_function, s_include);
frame.set(s_args, Array::Create(btArgs.m_parserFrame->filename));
}
bt.append(frame.toVariant());
depth++;
}
}
}
// Handle the subsequent VM frames
Offset prevPc = 0;
for (ActRec* prevFp = g_context->getPrevVMState(fp, &prevPc);
fp != nullptr && (btArgs.m_limit == 0 || depth < btArgs.m_limit);
fp = prevFp, pc = prevPc,
prevFp = g_context->getPrevVMState(fp, &prevPc)) {
// do not capture frame for HPHP only functions
if (fp->m_func->isNoInjection()) {
continue;
}
ArrayInit frame(7, ArrayInit::Map{});
auto const curUnit = fp->m_func->unit();
auto const curOp = *reinterpret_cast<const Op*>(curUnit->at(pc));
auto const isReturning =
curOp == Op::RetC || curOp == Op::RetV ||
curOp == Op::CreateCont || curOp == Op::Await ||
fp->localsDecRefd();
// Builtins and generators don't have a file and line number
if (prevFp && !prevFp->m_func->isBuiltin() && !fp->resumed()) {
auto const prevUnit = prevFp->m_func->unit();
auto prevFile = prevUnit->filepath();
if (prevFp->m_func->originalFilename()) {
prevFile = prevFp->m_func->originalFilename();
}
assert(prevFile);
frame.set(s_file, const_cast<StringData*>(prevFile));
// In the normal method case, the "saved pc" for line number printing is
// pointing at the cell conversion (Unbox/Pop) instruction, not the call
// itself. For multi-line calls, this instruction is associated with the
// subsequent line which results in an off-by-n. We're subtracting one
// in order to look up the line associated with the FCall/FCallArray
// instruction. Exception handling and the other opcodes (ex. BoxR)
// already do the right thing. The emitter associates object access with
// the subsequent expression and this would be difficult to modify.
auto const opAtPrevPc =
*reinterpret_cast<const Op*>(prevUnit->at(prevPc));
Offset pcAdjust = 0;
if (opAtPrevPc == OpPopR || opAtPrevPc == OpUnboxR) {
pcAdjust = 1;
}
frame.set(s_line,
prevFp->m_func->unit()->getLineNumber(prevPc - pcAdjust));
}
// check for include
String funcname = const_cast<StringData*>(fp->m_func->name());
if (fp->m_func->isClosureBody()) {
static StringData* s_closure_label =
makeStaticString("{closure}");
funcname = s_closure_label;
}
// check for pseudomain
if (funcname.empty()) {
if (!prevFp) continue;
funcname = s_include;
}
frame.set(s_function, funcname);
if (!funcname.same(s_include)) {
// Closures have an m_this but they aren't in object context
Class* ctx = arGetContextClass(fp);
if (ctx != nullptr && !fp->m_func->isClosureBody()) {
frame.set(s_class, ctx->name()->data());
if (fp->hasThis() && !isReturning) {
if (btArgs.m_withThis) {
frame.set(s_object, Object(fp->getThis()));
}
frame.set(s_type, "->");
} else {
frame.set(s_type, "::");
}
}
}
Array args = Array::Create();
if (btArgs.m_ignoreArgs) {
// do nothing
} else if (funcname.same(s_include)) {
if (depth) {
args.append(const_cast<StringData*>(curUnit->filepath()));
frame.set(s_args, args);
}
} else if (!RuntimeOption::EnableArgsInBacktraces || isReturning) {
// Provide an empty 'args' array to be consistent with hphpc
frame.set(s_args, args);
} else {
const int nparams = fp->m_func->numNonVariadicParams();
int nargs = fp->numArgs();
int nformals = std::min(nparams, nargs);
if (UNLIKELY(fp->hasVarEnv() && fp->getVarEnv()->getFP() != fp)) {
// VarEnv is attached to eval or debugger frame, other than the current
// frame. Access locals thru VarEnv.
auto varEnv = fp->getVarEnv();
auto func = fp->func();
for (int i = 0; i < nformals; i++) {
TypedValue *arg = varEnv->lookup(func->localVarName(i));
args.append(tvAsVariant(arg));
}
} else {
for (int i = 0; i < nformals; i++) {
TypedValue *arg = frame_local(fp, i);
args.append(tvAsVariant(arg));
}
}
/* builtin extra args are not stored in varenv */
if (nargs > nparams && fp->hasExtraArgs()) {
for (int i = nparams; i < nargs; i++) {
TypedValue *arg = fp->getExtraArg(i - nparams);
args.append(tvAsVariant(arg));
}
}
frame.set(s_args, args);
}
bt.append(frame.toVariant());
depth++;
}
return bt;
}
