// of ((offset)+0*8)(RSP) ~ ((offset)+9*8)(RSP).
//
// SAVE_F8_TO_F15(offset) saves F8 ~ F15 to the stack space
// of ((offset)+0*8)(RSP) ~ ((offset)+7*8)(RSP).
//
// R29 is not saved because Go will save and restore it.

#define SAVE_R19_TO_R28(offset) \
	STP	(R19, R20), ((offset)+0*8)(RSP) \
	STP	(R21, R22), ((offset)+2*8)(RSP) \
	STP	(R23, R24), ((offset)+4*8)(RSP) \

	MOVD	(g_sched+gobuf_sp)(g), R3
	MOVD	R3, RSP
	MOVD	(g_sched+gobuf_bp)(g), R29

	// call target function
	MOVD	0(R26), R3	// code pointer
	BL	(R3)

	// switch back to g
	MOVD	g_m(g), R3
	MOVD	m_curg(R3), g
	BL	runtime·save_g(SB)
	MOVD	(g_sched+gobuf_sp)(g), R0
	MOVD	R0, RSP
	MOVD	(g_sched+gobuf_bp)(g), R29
	MOVD	$0, (g_sched+gobuf_sp)(g)
	MOVD	$0, (g_sched+gobuf_bp)(g)
	RET

TEXT crosscall2(SB),NOSPLIT|NOFRAME,$0
	/*
	 * We still need to save all callee save register as before, and then
	 * push 3 args for fn (R4, R5, R7), skipping R6.
	 * Also note that at procedure entry in gc world, 8(R29) will be the
	 *  first arg.
	 */

	ADDV	$(-23*8), R3
	MOVV	R4, (1*8)(R3) // fn unsafe.Pointer
	MOVV	R5, (2*8)(R3) // a unsafe.Pointer
	MOVV	R7, (3*8)(R3) // ctxt uintptr

	SAVE_R22_TO_R31((4*8))

		// but clobbers R1 (LR) because it's a call
		// and R30 (REGTMP).
		// Returns a pointer to a write barrier buffer in R29.
		{name: "LoweredWB", argLength: 1, reg: regInfo{clobbers: (callerSave &^ gpg) | buildReg("R1"), outputs: []regMask{buildReg("R29")}}, clobberFlags: true, aux: "Int64"},

		// There are three of these functions so that they can have three different register inputs.

	MOVD	R23, (offset+8*9)(R1)  \
	MOVD	R24, (offset+8*10)(R1) \
	MOVD	R25, (offset+8*11)(R1) \
	MOVD	R26, (offset+8*12)(R1) \
	MOVD	R27, (offset+8*13)(R1) \
	MOVD	R28, (offset+8*14)(R1) \
	MOVD	R29, (offset+8*15)(R1) \
	MOVD	g,   (offset+8*16)(R1) \
	MOVD	R31, (offset+8*17)(R1)

#define RESTORE_GPR(offset)            \
	MOVD	(offset+8*0)(R1), R14  \
	MOVD	(offset+8*1)(R1), R15  \
	MOVD	(offset+8*2)(R1), R16  \

	// To defeat the linker, we make our own stack frame with
	// more space.
	SUB	$144+FIXED_FRAME, R1

	// Save registers
	MOVD	R31, 56(R1)
	MOVD	g, 64(R1)
	MOVD	R29, 72(R1)
	MOVD	R14, 80(R1)
	MOVD	R15, 88(R1)

	BL	runtime·load_g(SB)

	CMP	$0, g
	BEQ	sigtramp // g == nil
	MOVD	g_m(g), R6
	CMP	$0, R6
	BEQ	sigtramp	// g.m == nil

// 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"
#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

func (c *sigctxt) r26() uint64 { return c.regs().sc_regs[26] }
func (c *sigctxt) r27() uint64 { return c.regs().sc_regs[27] }
func (c *sigctxt) r28() uint64 { return c.regs().sc_regs[28] }
func (c *sigctxt) r29() uint64 { return c.regs().sc_regs[29] }
func (c *sigctxt) r30() uint64 { return c.regs().sc_regs[30] }
func (c *sigctxt) r31() uint64 { return c.regs().sc_regs[31] }
func (c *sigctxt) sp() uint64  { return c.regs().sc_regs[3] }

func (c *sigctxt) r26() uint64 { return c.regs().sc_regs[26] }
func (c *sigctxt) r27() uint64 { return c.regs().sc_regs[27] }
func (c *sigctxt) r28() uint64 { return c.regs().sc_regs[28] }
func (c *sigctxt) r29() uint64 { return c.regs().sc_regs[29] }
func (c *sigctxt) r30() uint64 { return c.regs().sc_regs[30] }
func (c *sigctxt) r31() uint64 { return c.regs().sc_regs[31] }
func (c *sigctxt) sp() uint64  { return c.regs().sc_regs[29] }

func (c *sigctxt) r26() uint64 { return c.regs().gpr[26] }
func (c *sigctxt) r27() uint64 { return c.regs().gpr[27] }
func (c *sigctxt) r28() uint64 { return c.regs().gpr[28] }
func (c *sigctxt) r29() uint64 { return c.regs().gpr[29] }
func (c *sigctxt) r30() uint64 { return c.regs().gpr[30] }
func (c *sigctxt) r31() uint64 { return c.regs().gpr[31] }
func (c *sigctxt) sp() uint64  { return c.regs().gpr[1] }

//go:nosplit