arch/mips/math-emu/dp_cmp.c

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

File Facts

System
Linux kernel
Corpus path
arch/mips/math-emu/dp_cmp.c
Extension
.c
Size
936 bytes
Lines
48
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"

int ieee754dp_cmp(union ieee754dp x, union ieee754dp y, int cmp, int sig)
{
	s64 vx;
	s64 vy;

	COMPXDP;
	COMPYDP;

	EXPLODEXDP;
	EXPLODEYDP;
	FLUSHXDP;
	FLUSHYDP;
	ieee754_clearcx();	/* Even clear inexact flag here */

	if (ieee754_class_nan(xc) || ieee754_class_nan(yc)) {
		if (sig ||
		    xc == IEEE754_CLASS_SNAN || yc == IEEE754_CLASS_SNAN)
			ieee754_setcx(IEEE754_INVALID_OPERATION);
		return (cmp & IEEE754_CUN) != 0;
	} else {
		vx = x.bits;
		vy = y.bits;

		if (vx < 0)
			vx = -vx ^ DP_SIGN_BIT;
		if (vy < 0)
			vy = -vy ^ DP_SIGN_BIT;

		if (vx < vy)
			return (cmp & IEEE754_CLT) != 0;
		else if (vx == vy)
			return (cmp & IEEE754_CEQ) != 0;
		else
			return (cmp & IEEE754_CGT) != 0;
	}
}

Annotation

Implementation Notes