[Intrinsic] Add fixed point saturating division intrinsics.

Summary:
This patch adds intrinsics and ISelDAG nodes for signed
and unsigned fixed-point division:

```
llvm.sdiv.fix.sat.*
llvm.udiv.fix.sat.*
```

These intrinsics perform scaled, saturating division
on two integers or vectors of integers. They are
required for the implementation of the Embedded-C
fixed-point arithmetic in Clang.

Reviewers: bjope, leonardchan, craig.topper

Subscribers: hiraditya, jdoerfert, llvm-commits

Tags: #llvm

Differential Revision: https://reviews.llvm.org/D71550

1 files changed, 2 insertions, 0 deletions

diff --git a/llvm/lib/CodeGen/TargetLoweringBase.cpp b/llvm/lib/CodeGen/TargetLoweringBase.cpp
index bd717a8..95c63d0 100644
--- a/llvm/lib/CodeGen/TargetLoweringBase.cpp
+++ b/llvm/lib/CodeGen/TargetLoweringBase.cpp
@@ -660,7 +660,9 @@ void TargetLoweringBase::initActions() {
     setOperationAction(ISD::UMULFIX, VT, Expand);
     setOperationAction(ISD::UMULFIXSAT, VT, Expand);
     setOperationAction(ISD::SDIVFIX, VT, Expand);
+    setOperationAction(ISD::SDIVFIXSAT, VT, Expand);
     setOperationAction(ISD::UDIVFIX, VT, Expand);
+    setOperationAction(ISD::UDIVFIXSAT, VT, Expand);
 
     // Overflow operations default to expand
     setOperationAction(ISD::SADDO, VT, Expand);