[ARM] VQSUB instruction

Same as VQADD, VQSUB can be selected from llvm.ssub.sat intrinsics.

Differential Revision: https://reviews.llvm.org/D68567

llvm-svn: 374377

2 files changed, 10 insertions, 0 deletions

diff --git a/llvm/lib/Target/ARM/ARMISelLowering.cpp b/llvm/lib/Target/ARM/ARMISelLowering.cpp
index 90b709867fe..d8b2c55eefe 100644
--- a/llvm/lib/Target/ARM/ARMISelLowering.cpp
+++ b/llvm/lib/Target/ARM/ARMISelLowering.cpp
@@ -267,6 +267,8 @@ void ARMTargetLowering::addMVEVectorTypes(bool HasMVEFP) {
     setOperationAction(ISD::BSWAP, VT, Legal);
     setOperationAction(ISD::SADDSAT, VT, Legal);
     setOperationAction(ISD::UADDSAT, VT, Legal);
+    setOperationAction(ISD::SSUBSAT, VT, Legal);
+    setOperationAction(ISD::USUBSAT, VT, Legal);
 
     // No native support for these.
     setOperationAction(ISD::UDIV, VT, Expand);
diff --git a/llvm/lib/Target/ARM/ARMInstrMVE.td b/llvm/lib/Target/ARM/ARMInstrMVE.td
index 28a32e1263d..80b45ce8914 100644
--- a/llvm/lib/Target/ARM/ARMInstrMVE.td
+++ b/llvm/lib/Target/ARM/ARMInstrMVE.td
@@ -1567,6 +1567,14 @@ let Predicates = [HasMVEInt] in {
     foreach VT = [instr.VT] in
       def : Pat<(VT (saddsat (VT MQPR:$Qm), (VT MQPR:$Qn))),
                 (VT (instr (VT MQPR:$Qm), (VT MQPR:$Qn)))>;
+  foreach instr = [MVE_VQSUBu8, MVE_VQSUBu16, MVE_VQSUBu32] in
+    foreach VT = [instr.VT] in
+      def : Pat<(VT (usubsat (VT MQPR:$Qm), (VT MQPR:$Qn))),
+                (VT (instr (VT MQPR:$Qm), (VT MQPR:$Qn)))>;
+  foreach instr = [MVE_VQSUBs8, MVE_VQSUBs16, MVE_VQSUBs32] in
+    foreach VT = [instr.VT] in
+      def : Pat<(VT (ssubsat (VT MQPR:$Qm), (VT MQPR:$Qn))),
+                (VT (instr (VT MQPR:$Qm), (VT MQPR:$Qn)))>;
 }