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// Copyright 2023 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"
#define PosInf 0x7FF0000000000000
// The rounding mode of RISC-V is different from Go spec.
#define ROUNDFN(NAME, MODE) \
TEXT NAME(SB),NOSPLIT,$0; \
MOVD x+0(FP), F0; \
/* whether x is NaN */; \
FEQD F0, F0, X6; \
BNEZ X6, 3(PC); \
/* return NaN if x is NaN */; \
MOVD F0, ret+8(FP); \
RET; \
MOV $PosInf, X6; \
FMVDX X6, F1; \
FABSD F0, F2; \
/* if abs(x) > +Inf, return Inf instead of round(x) */; \
FLTD F1, F2, X6; \
/* Inf should keep same signed with x then return */; \
BEQZ X6, 3(PC); \
FCVTLD.MODE F0, X6; \
FCVTDL X6, F1; \
/* rounding will drop signed bit in RISCV, restore it */; \
FSGNJD F0, F1, F0; \
MOVD F0, ret+8(FP); \
RET
// func archFloor(x float64) float64
ROUNDFN(·archFloor, RDN)
// func archCeil(x float64) float64
ROUNDFN(·archCeil, RUP)
// func archTrunc(x float64) float64
ROUNDFN(·archTrunc, RTZ)
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