diff --git a/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp b/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp
--- a/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp
+++ b/mlir/lib/Conversion/StandardToLLVM/StandardToLLVM.cpp
@@ -2304,6 +2304,11 @@
   using Super::Super;
 };
 
+struct FPToSILowering
+    : public OneToOneConvertToLLVMPattern<FPToSIOp, LLVM::FPToSIOp> {
+  using Super::Super;
+};
+
 struct FPTruncLowering
     : public OneToOneConvertToLLVMPattern<FPTruncOp, LLVM::FPTruncOp> {
   using Super::Super;
@@ -2975,6 +2980,7 @@
       Log10OpLowering,
       Log2OpLowering,
       FPExtLowering,
+      FPToSILowering,
       FPTruncLowering,
       ImOpLowering,
       IndexCastOpLowering,
diff --git a/mlir/test/Conversion/StandardToLLVM/convert-to-llvmir.mlir b/mlir/test/Conversion/StandardToLLVM/convert-to-llvmir.mlir
--- a/mlir/test/Conversion/StandardToLLVM/convert-to-llvmir.mlir
+++ b/mlir/test/Conversion/StandardToLLVM/convert-to-llvmir.mlir
@@ -618,6 +618,20 @@
   return
 }
 
+// Checking conversion of floating point to integer types.
+// CHECK-LABEL: @fptosi
+func @fptosi(%arg0 : f32, %arg1 : f64) {
+// CHECK-NEXT: = llvm.fptosi {{.*}} : !llvm.float to !llvm.i32
+  %0 = fptosi %arg0: f32 to i32
+// CHECK-NEXT: = llvm.fptosi {{.*}} : !llvm.float to !llvm.i64
+  %1 = fptosi %arg0: f32 to i64
+// CHECK-NEXT: = llvm.fptosi {{.*}} : !llvm.double to !llvm.i32
+  %2 = fptosi %arg1: f64 to i32
+// CHECK-NEXT: = llvm.fptosi {{.*}} : !llvm.double to !llvm.i64
+  %3 = fptosi %arg1: f64 to i64
+  return
+}
+
 // Checking conversion of integer types to floating point.
 // CHECK-LABEL: @fptrunc
 func @fptrunc(%arg0 : f32, %arg1 : f64) {