arch/powerpc/math-emu/fmuls.c

Source file repositories/reference/linux-study-clean/arch/powerpc/math-emu/fmuls.c

File Facts

System
Linux kernel
Corpus path
arch/powerpc/math-emu/fmuls.c
Extension
.c
Size
1052 bytes
Lines
48
Domain
Architecture Layer
Bucket
arch/powerpc
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
#include <linux/types.h>
#include <linux/errno.h>
#include <linux/uaccess.h>

#include <asm/sfp-machine.h>
#include <math-emu/soft-fp.h>
#include <math-emu/double.h>
#include <math-emu/single.h>

int
fmuls(void *frD, void *frA, void *frB)
{
	FP_DECL_D(A);
	FP_DECL_D(B);
	FP_DECL_D(R);
	FP_DECL_EX;

#ifdef DEBUG
	printk("%s: %p %p %p\n", __func__, frD, frA, frB);
#endif

	FP_UNPACK_DP(A, frA);
	FP_UNPACK_DP(B, frB);

#ifdef DEBUG
	printk("A: %ld %lu %lu %ld (%ld) [%08lx.%08lx %lx]\n",
	       A_s, A_f1, A_f0, A_e, A_c, A_f1, A_f0, A_e + 1023);
	printk("B: %ld %lu %lu %ld (%ld) [%08lx.%08lx %lx]\n",
	       B_s, B_f1, B_f0, B_e, B_c, B_f1, B_f0, B_e + 1023);
#endif

	if ((A_c == FP_CLS_INF && B_c == FP_CLS_ZERO) ||
	    (A_c == FP_CLS_ZERO && B_c == FP_CLS_INF))
		FP_SET_EXCEPTION(EFLAG_VXIMZ);

	FP_MUL_D(R, A, B);

#ifdef DEBUG
	printk("D: %ld %lu %lu %ld (%ld) [%08lx.%08lx %lx]\n",
	       R_s, R_f1, R_f0, R_e, R_c, R_f1, R_f0, R_e + 1023);
#endif

	__FP_PACK_DS(frD, R);

	return FP_CUR_EXCEPTIONS;
}

Annotation

Implementation Notes