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diff --git a/arch/microblaze/lib/mulsi3.S b/arch/microblaze/lib/mulsi3.S
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+/* SPDX-License-Identifier: GPL-2.0 */
+#include <linux/linkage.h>
+
+/*
+ * Multiply operation for 32 bit integers.
+ * Input : Operand1 in Reg r5
+ * Operand2 in Reg r6
+ * Output: Result [op1 * op2] in Reg r3
+ */
+ .text
+ .globl __mulsi3
+ .type __mulsi3, @function
+ .ent __mulsi3
+
+__mulsi3:
+ .frame r1, 0, r15
+ add r3, r0, r0
+ beqi r5, result_is_zero /* multiply by zero */
+ beqi r6, result_is_zero /* multiply by zero */
+ bgeid r5, r5_pos
+ xor r4, r5, r6 /* get the sign of the result */
+ rsubi r5, r5, 0 /* make r5 positive */
+r5_pos:
+ bgei r6, r6_pos
+ rsubi r6, r6, 0 /* make r6 positive */
+r6_pos:
+ bri l1
+l2:
+ add r5, r5, r5
+l1:
+ srl r6, r6
+ addc r7, r0, r0
+ beqi r7, l2
+ bneid r6, l2
+ add r3, r3, r5
+ blti r4, negateresult
+ rtsd r15, 8
+ nop
+negateresult:
+ rtsd r15, 8
+ rsub r3, r3, r0
+result_is_zero:
+ rtsd r15, 8
+ addi r3, r0, 0
+
+.size __mulsi3, . - __mulsi3
+.end __mulsi3