diff --git a/mlir/include/mlir/Dialect/SCF/SCFOps.td b/mlir/include/mlir/Dialect/SCF/SCFOps.td
--- a/mlir/include/mlir/Dialect/SCF/SCFOps.td
+++ b/mlir/include/mlir/Dialect/SCF/SCFOps.td
@@ -315,7 +315,9 @@
 }
 
 def IfOp : SCF_Op<"if",
-      [DeclareOpInterfaceMethods<RegionBranchOpInterface>,
+      [DeclareOpInterfaceMethods<RegionBranchOpInterface,
+                                 ["getNumRegionInvocations",
+                                  "getRegionInvocationBounds"]>,
        SingleBlockImplicitTerminator<"scf::YieldOp">, RecursiveSideEffects,
        NoRegionArguments]> {
   let summary = "if-then-else operation";
diff --git a/mlir/lib/Dialect/SCF/SCF.cpp b/mlir/lib/Dialect/SCF/SCF.cpp
--- a/mlir/lib/Dialect/SCF/SCF.cpp
+++ b/mlir/lib/Dialect/SCF/SCF.cpp
@@ -1189,6 +1189,14 @@
   return success();
 }
 
+void IfOp::getRegionInvocationBounds(
+    ArrayRef<Attribute> operands,
+    SmallVectorImpl<InvocationBounds> &invocationBounds) {
+  // If the condition was constant, then the op would have already been folded.
+  // Each region of the op is invoked at most once.
+  invocationBounds.assign(2, {0, 1});
+}
+
 namespace {
 // Pattern to remove unused IfOp results.
 struct RemoveUnusedResults : public OpRewritePattern<IfOp> {
diff --git a/mlir/test/Dialect/SCF/control-flow-sink.mlir b/mlir/test/Dialect/SCF/control-flow-sink.mlir
new file mode 100644
--- /dev/null
+++ b/mlir/test/Dialect/SCF/control-flow-sink.mlir
@@ -0,0 +1,60 @@
+// RUN: mlir-opt -split-input-file -control-flow-sink %s | FileCheck %s
+
+// CHECK-LABEL: @test_scf_if_sink
+// CHECK-SAME:  (%[[ARG0:.*]]: i1, %[[ARG1:.*]]: i32)
+// CHECK: %[[V0:.*]] = scf.if %[[ARG0]]
+// CHECK:   %[[V1:.*]] = arith.addi %[[ARG1]], %[[ARG1]]
+// CHECK:   scf.yield %[[V1]]
+// CHECK: else
+// CHECK:   %[[V1:.*]] = arith.muli %[[ARG1]], %[[ARG1]]
+// CHECK:   scf.yield %[[V1]]
+// CHECK: return %[[V0]]
+func @test_scf_if_sink(%arg0: i1, %arg1: i32) -> i32 {
+  %0 = arith.addi %arg1, %arg1 : i32
+  %1 = arith.muli %arg1, %arg1 : i32
+  %result = scf.if %arg0 -> i32 {
+    scf.yield %0 : i32
+  } else {
+    scf.yield %1 : i32
+  }
+  return %result : i32
+}
+
+// -----
+
+func private @consume(i32) -> ()
+
+// CHECK-LABEL: @test_scf_if_then_only_sink
+// CHECK-SAME:  (%[[ARG0:.*]]: i1, %[[ARG1:.*]]: i32)
+// CHECK: scf.if %[[ARG0]]
+// CHECK:   %[[V0:.*]] = arith.addi %[[ARG1]], %[[ARG1]]
+// CHECK:   call @consume(%[[V0]])
+func @test_scf_if_then_only_sink(%arg0: i1, %arg1: i32) {
+  %0 = arith.addi %arg1, %arg1 : i32
+  scf.if %arg0 {
+    call @consume(%0) : (i32) -> ()
+    scf.yield
+  }
+  return
+}
+
+// -----
+
+func private @consume(i32) -> ()
+
+// CHECK-LABEL: @test_scf_if_double_sink
+// CHECK-SAME:  (%[[ARG0:.*]]: i1, %[[ARG1:.*]]: i32)
+// CHECK: scf.if %[[ARG0]]
+// CHECK:   scf.if %[[ARG0]]
+// CHECK:     %[[V0:.*]] = arith.addi %[[ARG1]], %[[ARG1]]
+// CHECK:     call @consume(%[[V0]])
+func @test_scf_if_double_sink(%arg0: i1, %arg1: i32) {
+  %0 = arith.addi %arg1, %arg1 : i32
+  scf.if %arg0 {
+    scf.if %arg0 {
+      call @consume(%0) : (i32) -> ()
+      scf.yield
+    }
+  }
+  return
+}