diff --git a/kernel/x86_64/zgemm3m_kernel_4x4_haswell.c b/kernel/x86_64/zgemm3m_kernel_4x4_haswell.c
index c57dccd36..56bc06c5c 100644
--- a/kernel/x86_64/zgemm3m_kernel_4x4_haswell.c
+++ b/kernel/x86_64/zgemm3m_kernel_4x4_haswell.c
@@ -201,8 +201,8 @@
     "33105"#ndim":\n\t"\
     "movq %%r13,%4; movq %%r14,%1; movq %%r11,%7;"\
     :"+r"(a_pointer),"+r"(b_pointer),"+r"(c_pointer),"+r"(ldc_in_bytes),"+r"(K),"+r"(ctemp),"+r"(const_val),"+r"(M),"+r"(next_b)\
-    ::"r11","r12","r13","r14","r15","ymm0","ymm1","ymm2","ymm3","ymm4","ymm5","ymm6","ymm7","ymm8","ymm9","ymm10","ymm11","ymm12","ymm13","ymm14",\
-    "ymm15","cc","memory");\
+    ::"r11","r12","r13","r14","r15","xmm0","xmm1","xmm2","xmm3","xmm4","xmm5","xmm6","xmm7","xmm8","xmm9","xmm10","xmm11","xmm12","xmm13","xmm14",\
+    "xmm15","cc","memory");\
     a_pointer -= M * K; b_pointer += ndim * K; c_pointer += 2*(LDC * ndim - M);\
 }
 int __attribute__ ((noinline))