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-rw-r--r--sysdeps/i960/sub_n.s21
1 files changed, 21 insertions, 0 deletions
diff --git a/sysdeps/i960/sub_n.s b/sysdeps/i960/sub_n.s
new file mode 100644
index 0000000000..13ebbfa9f2
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+++ b/sysdeps/i960/sub_n.s
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+.text
+	.align 4
+	.globl ___mpn_sub_n
+___mpn_sub_n:
+	mov	1,g6		# set carry-save register
+	cmpo	1,0		# clear cy
+
+Loop:	subo	1,g3,g3		# update loop counter
+	ld	(g1),g5		# load from s1_ptr
+	addo	4,g1,g1		# s1_ptr++
+	ld	(g2),g4		# load from s2_ptr
+	addo	4,g2,g2		# s2_ptr++
+	cmpo	g6,1		# restore cy from g6, relies on cy being 0
+	subc	g4,g5,g4	# main subtract
+	subc	0,0,g6		# save cy in g6
+	st	g4,(g0)		# store result to res_ptr
+	addo	4,g0,g0		# res_ptr++
+	cmpobne	0,g3,Loop	# when branch is taken, cy will be 0
+
+	mov	g6,g0
+	ret