X-Git-Url: https://git.libre-soc.org/?p=soc.git;a=blobdiff_plain;f=src%2Fsoc%2Fdecoder%2Fisa%2Fcaller.py;h=299b74c0e136a65a0f1a68955e6ccda786e2cf99;hp=36921d5f70519859c5a28cc6e0d6117107911b90;hb=7bcc2eb604806b9b69993974cb0b5519136a7d01;hpb=6e3c0a3f8bebb432e702b8e4d2627a3503d6b179

diff --git a/src/soc/decoder/isa/caller.py b/src/soc/decoder/isa/caller.py
index 36921d5f..299b74c0 100644
--- a/src/soc/decoder/isa/caller.py
+++ b/src/soc/decoder/isa/caller.py
@@ -273,16 +273,17 @@ class ISACaller:
             imm = yield self.dec2.e.imm_data.data
             inputs.append(SelectableInt(imm, 64))
         assert len(outputs) >= 1
-        output = outputs[0]
-        input_sgn = [exts(x.value, x.bits) < 0 for x in inputs]
-        output_sgn = exts(output.value, output.bits) < 0
-        ov = 1 if input_sgn[0] == input_sgn[1] and \
-            output_sgn != input_sgn[0] else 0
-
-        self.spr['XER'][XER_bits['OV']] = ov
-        so = self.spr['XER'][XER_bits['SO']]
-        so = so | ov
-        self.spr['XER'][XER_bits['SO']] = so
+        if len(inputs) >= 2:
+            output = outputs[0]
+            input_sgn = [exts(x.value, x.bits) < 0 for x in inputs]
+            output_sgn = exts(output.value, output.bits) < 0
+            ov = 1 if input_sgn[0] == input_sgn[1] and \
+                output_sgn != input_sgn[0] else 0
+
+            self.spr['XER'][XER_bits['OV']] = ov
+            so = self.spr['XER'][XER_bits['SO']]
+            so = so | ov
+            self.spr['XER'][XER_bits['SO']] = so