// Copyright 2022 The Go Authors. All rights reserved.
// Use of this source code is governed by a BSD-style
// license that can be found in the LICENSE file.

#include "textflag.h"

TEXT ·RewindAndSetgid(SB),NOSPLIT|NOFRAME,$0-0
	// Rewind stack pointer so anything that happens on the stack
	// will clobber the test pattern created by the caller
	ADDV	$(1024*8), R3

	// Ask signaller to setgid
	MOVW	$1, R12
	DBAR
	MOVW	R12, ·Baton(SB)

#define SETB_CR0(rout) _SETB(CR0LT, CR0EQ, rout)
#define SETB_CR1(rout) _SETB(CR1LT, CR1EQ, rout)
#define SETB_INIT() \
	MOVD	$-1,R20 \
	MOVD	$1,R21
#endif

TEXT ·Compare<ABIInternal>(SB),NOSPLIT|NOFRAME,$0-56
	// incoming:
	// R3 a addr
	// R4 a len
	// R6 b addr
	// R7 b len
	//
	// on entry to cmpbody:
	// R3 return value if len(a) == len(b)
	// R5 a addr
	// R6 b addr
	// R9 min(len(a),len(b))

// func crosscall2(fn, a unsafe.Pointer, n int32, ctxt uintptr)
// Saves C callee-saved registers and calls cgocallback with three arguments.
// fn is the PC of a func(a unsafe.Pointer) function.
TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0
	/*
	 * We still need to save all callee save register as before, and then
	 *  push 3 args for fn (R0, R1, R3), skipping R2.
	 * Also note that at procedure entry in gc world, 8(RSP) will be the
	 *  first arg.
	 */

				frames     = make(map[string]format.Frame)
				framesSize = 0
			)
			for i, ev := range sizes {
				eventsSize += ev.Sz

				// Add required stack frames. Note that they
				// may already be in the map.
				for _, id := range ev.Frames {
					s := strconv.Itoa(id)
					_, ok := frames[s]
					if ok {
						continue
					}
					f := allFrames[s]
					frames[s] = f

						break
					}
					i++
				}
				tb.frames = tb.frames[1:]
			}
			if !t.Failed() && len(tb.frames) > 0 {
				t.Errorf("got %d more frames than expected", len(tb.frames))
			}
			if t.Failed() {
				t.Logf("traceback diverged at frame %d", i)
				off := len(stack)
				if len(tb.frames) > 0 {
					off = tb.frames[0].off
				}
				t.Logf("traceback before error:\n%s", stack[:off])

	return
}

// ShowFrom drops all stack frames above the highest matching frame and returns
// whether a match was found. If showFrom is nil it returns false and does not
// modify the profile.
//
// Example: consider a sample with frames [A, B, C, B], where A is the root.
// ShowFrom(nil) returns false and has frames [A, B, C, B].
// ShowFrom(A) returns true and has frames [A, B, C, B].

//go:noinline
func f() {
	q := p
	x = 11  // line 23
	*q = 12 // line 24
}
func main() {
	defer func() {
		recover()
		var pcs [10]uintptr
		n := runtime.Callers(1, pcs[:])
		frames := runtime.CallersFrames(pcs[:n])
		for {
			f, more := frames.Next()
			if f.Function == "main.f" && f.Line != 24 {
				panic(fmt.Errorf("expected line 24, got line %d", f.Line))
			}
			if !more {
				break
			}
		}
	}()
	f()

	// "main.main".
	println(caller().name())
}

func caller() call {
	var pcs [3]uintptr
	n := runtime.Callers(1, pcs[:])
	frames := runtime.CallersFrames(pcs[:n])
	frame, _ := frames.Next()
	frame, _ = frames.Next()

	return call{frame: frame}
}

type call struct {
	frame runtime.Frame
}

func (c call) name() string {
	return c.frame.Function

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

//
// System calls for AMD64, Linux
//

#define SYS_gettimeofday 96

// func rawVforkSyscall(trap, a1, a2, a3 uintptr) (r1, err uintptr)
TEXT ·rawVforkSyscall(SB),NOSPLIT|NOFRAME,$0-48
	MOVQ	a1+8(FP), DI
	MOVQ	a2+16(FP), SI
	MOVQ	a3+24(FP), DX
	MOVQ	$0, R10
	MOVQ	$0, R8
	MOVQ	$0, R9
	MOVQ	trap+0(FP), AX	// syscall entry
	POPQ	R12 // preserve return address
	SYSCALL
	PUSHQ	R12

// license that can be found in the LICENSE file.

#include "textflag.h"

//
// System calls for riscv64, Linux
//

// func rawVforkSyscall(trap, a1, a2, a3 uintptr) (r1, err uintptr)
TEXT ·rawVforkSyscall(SB),NOSPLIT|NOFRAME,$0-48
	MOV	a1+8(FP), A0
	MOV	a2+16(FP), A1
	MOV	a3+24(FP), A2
	MOV	ZERO, A3
	MOV	ZERO, A4
	MOV	ZERO, A5
	MOV	trap+0(FP), A7	// syscall entry
	ECALL
	MOV	$-4096, T0
	BLTU	T0, A0, err