aboutsummaryrefslogtreecommitdiff
path: root/arch/metag/lib/cmpdi2.S
diff options
context:
space:
mode:
Diffstat (limited to 'arch/metag/lib/cmpdi2.S')
-rw-r--r--arch/metag/lib/cmpdi2.S32
1 files changed, 32 insertions, 0 deletions
diff --git a/arch/metag/lib/cmpdi2.S b/arch/metag/lib/cmpdi2.S
new file mode 100644
index 00000000000..9c5c663c5ae
--- /dev/null
+++ b/arch/metag/lib/cmpdi2.S
@@ -0,0 +1,32 @@
+! Copyright (C) 2012 by Imagination Technologies Ltd.
+!
+! 64-bit signed compare routine.
+!
+
+ .text
+ .global ___cmpdi2
+ .type ___cmpdi2,function
+
+! low high
+! s64 a (D0Ar2, D1Ar1)
+! s64 b (D0Ar4, D1Ar3)
+___cmpdi2:
+ ! start at 1 (equal) and conditionally increment or decrement
+ MOV D0Re0,#1
+
+ ! high words differ?
+ CMP D1Ar1,D1Ar3
+ BNE $Lhigh_differ
+
+ ! unsigned compare low words
+ CMP D0Ar2,D0Ar4
+ SUBLO D0Re0,D0Re0,#1
+ ADDHI D0Re0,D0Re0,#1
+ MOV PC,D1RtP
+
+$Lhigh_differ:
+ ! signed compare high words
+ SUBLT D0Re0,D0Re0,#1
+ ADDGT D0Re0,D0Re0,#1
+ MOV PC,D1RtP
+ .size ___cmpdi2,.-___cmpdi2