mips64/axpy: fix error when INCY == 0

Author: Aleksey Kuleshov

kernel/mips64/axpy.S

@@ -225,7 +225,9 @@
 	.align 3
 
 .L20:
+	beqz	INCY, .L27
 	dsra	I, N, 3
+
 	move	YY, Y
 
 	blez	I, .L25
@@ -405,5 +407,19 @@
 
 	j	$31
 	NOP
+	.align 3
+
+.L27:
+	LD	b1,  0 * SIZE(Y)
+
+.L28:
+	daddiu	N, N, -1
+	LD	a1,  0 * SIZE(X)
+	daddu	X, X, INCX
+	bgtz	N, .L28
+	MADD	b1, b1, ALPHA, a1
+
+	j	.L999
+	ST	b1,  0 * SIZE(Y)
 
 	EPILOGUE