xref: /openbmc/linux/arch/powerpc/math-emu/fsub.c (revision c4c3c32d)
1 // SPDX-License-Identifier: GPL-2.0
2 #include <linux/types.h>
3 #include <linux/errno.h>
4 #include <linux/uaccess.h>
5 
6 #include <asm/sfp-machine.h>
7 #include <math-emu/soft-fp.h>
8 #include <math-emu/double.h>
9 
10 int
11 fsub(void *frD, void *frA, void *frB)
12 {
13 	FP_DECL_D(A);
14 	FP_DECL_D(B);
15 	FP_DECL_D(R);
16 	FP_DECL_EX;
17 
18 #ifdef DEBUG
19 	printk("%s: %p %p %p\n", __func__, frD, frA, frB);
20 #endif
21 
22 	FP_UNPACK_DP(A, frA);
23 	FP_UNPACK_DP(B, frB);
24 
25 #ifdef DEBUG
26 	printk("A: %ld %lu %lu %ld (%ld)\n", A_s, A_f1, A_f0, A_e, A_c);
27 	printk("B: %ld %lu %lu %ld (%ld)\n", B_s, B_f1, B_f0, B_e, B_c);
28 #endif
29 
30 	if (B_c != FP_CLS_NAN)
31 		B_s ^= 1;
32 
33 	if (A_s != B_s && A_c == FP_CLS_INF && B_c == FP_CLS_INF)
34 		FP_SET_EXCEPTION(EFLAG_VXISI);
35 
36 	FP_ADD_D(R, A, B);
37 
38 #ifdef DEBUG
39 	printk("D: %ld %lu %lu %ld (%ld)\n", R_s, R_f1, R_f0, R_e, R_c);
40 #endif
41 
42 	__FP_PACK_D(frD, R);
43 
44 	return FP_CUR_EXCEPTIONS;
45 }
46