arch/mips/math-emu/dp_fint.c

Source file repositories/reference/linux-study-clean/arch/mips/math-emu/dp_fint.c

File Facts

System
Linux kernel
Corpus path
arch/mips/math-emu/dp_fint.c
Extension
.c
Size
820 bytes
Lines
45
Domain
Architecture Layer
Bucket
arch/mips
Inferred role
Architecture Layer: implementation source
Status
source implementation candidate

Why This File Exists

CPU and platform-specific kernel glue: boot entry, traps, syscall entry, interrupts, page tables, context switch, and low-level barriers.

Dependency Surface

Detected Declarations

Annotated Snippet

// SPDX-License-Identifier: GPL-2.0-only
/* IEEE754 floating point arithmetic
 * double precision: common utilities
 */
/*
 * MIPS floating point support
 * Copyright (C) 1994-2000 Algorithmics Ltd.
 */

#include "ieee754dp.h"

union ieee754dp ieee754dp_fint(int x)
{
	u64 xm;
	int xe;
	int xs;

	ieee754_clearcx();

	if (x == 0)
		return ieee754dp_zero(0);
	if (x == 1 || x == -1)
		return ieee754dp_one(x < 0);
	if (x == 10 || x == -10)
		return ieee754dp_ten(x < 0);

	xs = (x < 0);
	if (xs) {
		if (x == (1 << 31))
			xm = ((unsigned) 1 << 31);	/* max neg can't be safely negated */
		else
			xm = -x;
	} else {
		xm = x;
	}

	/* normalize - result can never be inexact or overflow */
	xe = DP_FBITS;
	while ((xm >> DP_FBITS) == 0) {
		xm <<= 1;
		xe--;
	}
	return builddp(xs, xe + DP_EBIAS, xm & ~DP_HIDDEN_BIT);
}

Annotation

Implementation Notes