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Diffstat (limited to 'sysdeps/i960/sub_n.s')
-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
--- /dev/null
+++ b/sysdeps/i960/sub_n.s
@@ -0,0 +1,21 @@
+.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