From 22e2b805ef3c4caa971fad3656976b6e0017aff3 Mon Sep 17 00:00:00 2001
From: Christian Ulmann <christian.ulmann@nextsilicon.com>
Date: Fri, 22 Sep 2023 14:07:47 +0200
Subject: [PATCH] [MLIR][UB] Add inliner interface for UB dialect (#67115)

This revision adds an inliner interface to the UB dialect that allows
inlining of `ub.poison` operations.
---
 mlir/lib/Dialect/UB/IR/UBOps.cpp   | 15 +++++++++++++++
 mlir/test/Dialect/UB/inlining.mlir | 13 +++++++++++++
 2 files changed, 28 insertions(+)
 create mode 100644 mlir/test/Dialect/UB/inlining.mlir

diff --git a/mlir/lib/Dialect/UB/IR/UBOps.cpp b/mlir/lib/Dialect/UB/IR/UBOps.cpp
index d63da90e16195f..e0cd5dafcfa61e 100644
--- a/mlir/lib/Dialect/UB/IR/UBOps.cpp
+++ b/mlir/lib/Dialect/UB/IR/UBOps.cpp
@@ -7,6 +7,7 @@
 //===----------------------------------------------------------------------===//
 
 #include "mlir/Dialect/UB/IR/UBOps.h"
+#include "mlir/Transforms/InliningUtils.h"
 
 #include "mlir/IR/Builders.h"
 #include "mlir/IR/DialectImplementation.h"
@@ -17,6 +18,19 @@
 using namespace mlir;
 using namespace mlir::ub;
 
+namespace {
+/// This class defines the interface for handling inlining with UB
+/// operations.
+struct UBInlinerInterface : public DialectInlinerInterface {
+  using DialectInlinerInterface::DialectInlinerInterface;
+
+  /// All UB ops can be inlined.
+  bool isLegalToInline(Operation *, Region *, bool, IRMapping &) const final {
+    return true;
+  }
+};
+} // namespace
+
 //===----------------------------------------------------------------------===//
 // UBDialect
 //===----------------------------------------------------------------------===//
@@ -30,6 +44,7 @@ void UBDialect::initialize() {
 #define GET_ATTRDEF_LIST
 #include "mlir/Dialect/UB/IR/UBOpsAttributes.cpp.inc"
       >();
+  addInterfaces<UBInlinerInterface>();
 }
 
 Operation *UBDialect::materializeConstant(OpBuilder &builder, Attribute value,
diff --git a/mlir/test/Dialect/UB/inlining.mlir b/mlir/test/Dialect/UB/inlining.mlir
new file mode 100644
index 00000000000000..cb76750044a3b8
--- /dev/null
+++ b/mlir/test/Dialect/UB/inlining.mlir
@@ -0,0 +1,13 @@
+// RUN: mlir-opt %s -inline -split-input-file | FileCheck %s
+
+func.func @func() -> i32 {
+  %0 = ub.poison : i32
+  return %0 : i32
+}
+
+// CHECK-LABEL: func @test_inline
+func.func @test_inline(%ptr : !llvm.ptr) -> i32 {
+// CHECK-NOT: call
+  %0 = call @func() : () -> i32
+  return %0 : i32
+}