diff options
Diffstat (limited to 'src/runtime/traceback.go')
| -rw-r--r-- | src/runtime/traceback.go | 66 |
1 files changed, 34 insertions, 32 deletions
diff --git a/src/runtime/traceback.go b/src/runtime/traceback.go index 8ecddc8935..0c8e5bace3 100644 --- a/src/runtime/traceback.go +++ b/src/runtime/traceback.go @@ -285,20 +285,7 @@ func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max in frame.varp -= goarch.PtrSize } - // Derive size of arguments. - // Most functions have a fixed-size argument block, - // so we can use metadata about the function f. - // Not all, though: there are some variadic functions - // in package runtime and reflect, and for those we use call-specific - // metadata recorded by f's caller. - if callback != nil || printing { - frame.argp = frame.fp + sys.MinFrameSize - var ok bool - frame.arglen, frame.argmap, ok = getArgInfoFast(f, callback != nil) - if !ok { - frame.arglen, frame.argmap = getArgInfo(&frame, callback != nil) - } - } + frame.argp = frame.fp + sys.MinFrameSize // Determine frame's 'continuation PC', where it can continue. // Normally this is the return address on the stack, but if sigpanic @@ -491,7 +478,6 @@ func gentraceback(pc0, sp0, lr0 uintptr, gp *g, skip int, pcbuf *uintptr, max in frame.lr = 0 frame.sp = frame.fp frame.fp = 0 - frame.argmap = nil // On link register architectures, sighandler saves the LR on stack // before faking a call. @@ -670,21 +656,33 @@ type reflectMethodValue struct { argLen uintptr // just args } -// getArgInfoFast returns the argument frame information for a call to f. -// It is short and inlineable. However, it does not handle all functions. -// If ok reports false, you must call getArgInfo instead. -// TODO(josharian): once we do mid-stack inlining, -// call getArgInfo directly from getArgInfoFast and stop returning an ok bool. -func getArgInfoFast(f funcInfo, needArgMap bool) (arglen uintptr, argmap *bitvector, ok bool) { - return uintptr(f.args), nil, !(needArgMap && f.args == _ArgsSizeUnknown) +// argBytes returns the argument frame size for a call to frame.fn. +func (frame *stkframe) argBytes() uintptr { + if frame.fn.args != _ArgsSizeUnknown { + return uintptr(frame.fn.args) + } + // This is an uncommon and complicated case. Fall back to fully + // fetching the argument map to compute its size. + argMap, _ := frame.argMapInternal() + return uintptr(argMap.n) * goarch.PtrSize } -// getArgInfo returns the argument frame information for a call to f -// with call frame frame. -func getArgInfo(frame *stkframe, needArgMap bool) (arglen uintptr, argmap *bitvector) { +// argMapInternal is used internally by stkframe to fetch special +// argument maps. +// +// argMap.n is always populated with the size of the argument map. +// +// argMap.bytedata is only populated for dynamic argument maps (used +// by reflect). If the caller requires the argument map, it should use +// this if non-nil, and otherwise fetch the argument map using the +// current PC. +// +// hasReflectStackObj indicates that this frame also has a reflect +// function stack object, which the caller must synthesize. +func (frame *stkframe) argMapInternal() (argMap bitvector, hasReflectStackObj bool) { f := frame.fn - arglen = uintptr(f.args) - if needArgMap && f.args == _ArgsSizeUnknown { + argMap.n = f.args / goarch.PtrSize + if f.args == _ArgsSizeUnknown { // Extract argument bitmaps for reflect stubs from the calls they made to reflect. switch funcname(f) { case "reflect.makeFuncStub", "reflect.methodValueCall": @@ -715,8 +713,9 @@ func getArgInfo(frame *stkframe, needArgMap bool) (arglen uintptr, argmap *bitve print("runtime: confused by ", funcname(f), ": no frame (sp=", hex(frame.sp), " fp=", hex(frame.fp), ") at entry+", hex(frame.pc-f.entry()), "\n") throw("reflect mismatch") } - return 0, nil + return bitvector{}, false // No locals, so also no stack objects } + hasReflectStackObj = true mv := *(**reflectMethodValue)(unsafe.Pointer(arg0)) // Figure out whether the return values are valid. // Reflect will update this value after it copies @@ -726,12 +725,15 @@ func getArgInfo(frame *stkframe, needArgMap bool) (arglen uintptr, argmap *bitve print("runtime: confused by ", funcname(f), "\n") throw("reflect mismatch") } - bv := mv.stack - arglen = uintptr(bv.n * goarch.PtrSize) + argMap = *mv.stack if !retValid { - arglen = uintptr(mv.argLen) &^ (goarch.PtrSize - 1) + // argMap.n includes the results, but + // those aren't valid, so drop them. + n := int32((uintptr(mv.argLen) &^ (goarch.PtrSize - 1)) / goarch.PtrSize) + if n < argMap.n { + argMap.n = n + } } - argmap = bv } } return |