func (frame *stkframe) argBytes() uintptr {
	if frame.fn.args != abi.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
}

// argMapInternal is used internally by stkframe to fetch special
// argument maps.
//

// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include "textflag.h"
#include "funcdata.h"

#define	REGCTXT	R29

// The frames of each of the two functions below contain two locals, at offsets
// that are known to the runtime.
//
// The first local is a bool called retValid with a whole pointer-word reserved

	}
	rest := got[loc[1]:]

	// Look for any frames after the signal handler. We want to see
	// symbolized frames, not garbage unknown frames.
	//
	// Since the signal might not be delivered to the main thread we can't
	// look for main.main. Every thread should have a runtime frame though.
	re = regexp.MustCompile(`#.* runtime\.`)
	if found := re.Find(rest) != nil; !found {

	}
	pp := objw.NewProgs(fn, worker)
	defer pp.Free()
	genssa(f, pp)
	// Check frame size again.
	// The check above included only the space needed for local variables.
	// After genssa, the space needed includes local variables and the callee arg region.
	// We must do this check prior to calling pp.Flush.
	// If there are any oversized stack frames,
	// the assembler may emit inscrutable complaints about invalid instructions.

	if n < 1 {
		return
	}
	frame, _ := CallersFrames(rpc).Next()
	return frame.PC, frame.File, frame.Line, frame.PC != 0
}

// Callers fills the slice pc with the return program counters of function invocations
// on the calling goroutine's stack. The argument skip is the number of stack frames
// to skip before recording in pc, with 0 identifying the frame for Callers itself and
// 1 identifying the caller of Callers.

    while (buffer.size != 1024L) source.read(buffer, 1024)
    stream1.close(ErrorCode.CANCEL, null)
    val frame1 = peer.takeFrame()
    assertThat(frame1.type).isEqualTo(Http2.TYPE_HEADERS)
    val frame2 = peer.takeFrame()
    assertThat(frame2.type).isEqualTo(Http2.TYPE_RST_STREAM)
    val frame3 = peer.takeFrame()
    assertThat(frame3.type).isEqualTo(Http2.TYPE_RST_STREAM)
    assertThat(connection.readBytes.acknowledged).isEqualTo(0L)

    close(ErrorCode.PROTOCOL_ERROR, ErrorCode.PROTOCOL_ERROR, e)
  }

  /**
   * Sends any initial frames and starts reading frames from the remote peer. This should be called
   * after [Builder.build] for all new connections.
   *
   * @param sendConnectionPreface true to send connection preface frames. This should always be true
   *     except for in tests that don't check for a connection preface.

		t.Fatalf("unexpected: %v %d %v", err, n, buf)
	}
	// read the remaining frame
	buf = make([]byte, 2)
	if n, err := r.Read(buf); err != nil && n != 2 && bytes.Equal(buf, []byte{0x03, 0x04}) {
		t.Fatalf("unexpected: %v %d %v", err, n, buf)
	}
	// read with buffer equal to frame
	buf = make([]byte, 3)
	if n, err := r.Read(buf); err != nil && n != 3 && bytes.Equal(buf, []byte{0x05, 0x06, 0x07}) {

func formatStack(pcs []uintptr) string {
	// When debugging, show file/line/content of files other than this one.
	const debug = false

	var buf strings.Builder
	i := 0
	frames := runtime.CallersFrames(pcs)
	for {
		fr, more := frames.Next()
		if debug {
			fmt.Fprintf(&buf, "pc=%x ", pcs[i])
			i++
		}
		if base := filepath.Base(fr.File); base == "traceback_system_test.go" || debug {

      assertThat(expected.message)
        .isEqualTo("Client-sent frames must be masked.")
    }
  }

  @Test fun serverSentFramesMustNotBeMasked() {
    data.write("8180".decodeHex())
    assertFailsWith<ProtocolException> {
      clientReader.processNextFrame()
    }.also { expected ->
      assertThat(expected.message)
        .isEqualTo("Server-sent frames must not be masked.")
    }
  }