// Copyright (c) 2026 Petr Balvín <opensource@petrbalvin.org> (https://petrbalvin.org)
// SPDX-License-Identifier: BSD-3-Clause

// Differential kernel for the arm64 SIMD arrangement bits: the FP one-bit
// size field (S=0, D=1 at bit 22), the immh field of the long extends, the
// narrow family's fixed bit 16, the SSHL/USHL size bits, the scalar D forms
// of the bare VADD/VSUB spellings and the INS lane packing.  Every function
// is byte-compared against go tool asm.

#include "textflag.h"

// func fpthree()
TEXT ·fpthree(SB), NOSPLIT, $0-0
	VFADD   V0.S4, V0.S4, V1.S4
	VFADD   V0.D2, V0.D2, V1.D2
	VFMUL   V0.S4, V0.S4, V1.S4
	VFMUL   V0.D2, V0.D2, V1.D2
	VFDIV   V0.S4, V0.S4, V1.S4
	VFDIV   V0.D2, V0.D2, V1.D2
	VFMLA   V1.D2, V12.D2, V1.D2
	VFMLA   V1.S2, V12.S2, V1.S2
	VFMLA   V1.S4, V12.S4, V1.S4
	VFMAX   V3.S4, V2.S4, V1.S4
	VFMAXNM V3.S4, V2.S4, V1.S4
	VFADDP  V3.D2, V2.D2, V1.D2
	VFCMEQ  V1.S4, V2.S4, V3.S4
	VFCMGE  V1.S4, V2.S4, V3.S4
	RET

// func fpunary()
TEXT ·fpunary(SB), NOSPLIT, $0-0
	VFABS   V0.D2, V1.D2
	VFNEG   V0.D2, V1.D2
	VFSQRT  V0.D2, V1.D2
	VFRINTN V0.D2, V1.D2
	VFRINTP V0.D2, V1.D2
	VFRINTM V0.D2, V1.D2
	VFRINTZ V0.D2, V1.D2
	VFCVTZS V1.D2, V2.D2
	VFCVTZU V1.D2, V2.D2
	VSCVTF  V1.D2, V2.D2
	VUCVTF  V1.D2, V2.D2
	VFABS   V0.S4, V1.S4
	VSCVTF  V1.S4, V2.S4
	VFNEG   V0.S2, V1.S2
	RET

// func shifts()
TEXT ·shifts(SB), NOSPLIT, $0-0
	VSSHL V1.S4, V2.S4, V3.S4
	VSSHL V1.S2, V2.S2, V3.S2
	VSSHL V1.H4, V2.H4, V3.H4
	VSSHL V1.H8, V2.H8, V3.H8
	VSSHL V1.B8, V2.B8, V3.B8
	VSSHL V1.B16, V2.B16, V3.B16
	VUSHL V1.S4, V2.S4, V3.S4
	VUSHL V1.S2, V2.S2, V3.S2
	VUSHL V1.H4, V2.H4, V3.H4
	VUSHL V1.H8, V2.H8, V3.H8
	VUSHL V1.B8, V2.B8, V3.B8
	VUSHL V1.B16, V2.B16, V3.B16
	VRBIT V24.B8, V24.B8
	RET

// func widen()
TEXT ·widen(SB), NOSPLIT, $0-0
	VUXTL   V30.B8, V30.H8
	VUXTL   V30.H4, V29.S4
	VUXTL   V29.S2, V2.D2
	VUXTL2  V30.H8, V30.S4
	VUXTL2  V29.S4, V2.D2
	VUXTL2  V30.B16, V2.H8
	VSXTL   V1.B8, V2.H8
	VSXTL   V1.H4, V2.S4
	VSXTL   V1.S2, V2.D2
	VSXTL2  V1.B16, V2.H8
	VSXTL2  V1.H8, V2.S4
	VSXTL2  V1.S4, V2.D2
	VXTN    V1.H8, V2.B8
	VXTN    V1.S4, V2.H4
	VXTN    V1.D2, V2.S2
	VXTN2   V1.H8, V2.B16
	VSQXTN  V1.D2, V2.S2
	VSQXTN2 V1.S4, V2.H8
	VSQXTUN V1.H8, V2.B8
	VUQXTN  V1.S4, V2.H4
	VUQXTN2 V1.D2, V2.S4
	RET

// func uaddw()
TEXT ·uaddw(SB), NOSPLIT, $0-0
	VUADDW  V9.B8, V12.H8, V14.H8
	VUADDW  V13.H4, V10.S4, V11.S4
	VUADDW  V21.S2, V24.D2, V29.D2
	VUADDW2 V9.B16, V12.H8, V14.H8
	VUADDW2 V13.H8, V20.S4, V30.S4
	VUADDW2 V21.S4, V24.D2, V29.D2
	RET

// func bareadd()
TEXT ·bareadd(SB), NOSPLIT, $0-0
	VADD V1, V2, V3
	VADD V1, V3, V3
	VSUB V12, V30, V30
	VSUB V12, V20, V30
	VADD V1.B8, V2.B8, V3.B8
	VSUB V12.B8, V30.B8, V30.B8
	RET

// func lanes()
TEXT ·lanes(SB), NOSPLIT, $0-0
	VMOV V12.D[0], V12.D[1]
	VMOV V10.S[0], V12.S[1]
	VMOV V9.H[0], V12.H[1]
	VMOV V12.B[0], V12.B[1]
	VMOV V12.S[2], V12.S[3]
	VMOV V12.H[3], V12.H[5]
	RET