From 81aca3f0d89bf3d1e76e511c097016e86629c3e3 Mon Sep 17 00:00:00 2001
From: Tobias Gysi <tobias.gysi@nextsilicon.com>
Date: Fri, 22 Sep 2023 18:55:49 +0000
Subject: [PATCH] [mlir][llvm] Replace NullOp by ZeroOp

This revision replaces the LLVM dialect NullOp by the recently
introduced ZeroOp. The ZeroOp is more generic in the sense that it
represents zero values of any LLVM type rather than null pointers only.

This is a follow to https://github.com/llvm/llvm-project/pull/65508
---
 flang/lib/Optimizer/CodeGen/CodeGen.cpp       | 14 ++++----
 flang/test/Fir/convert-to-llvm.fir            | 36 +++++++++----------
 flang/test/Fir/embox-char.fir                 |  4 +--
 flang/test/Fir/embox-substring.fir            |  2 +-
 flang/test/Fir/tbaa.fir                       |  4 +--
 mlir/docs/Dialects/LLVM.md                    | 17 ++++-----
 .../mlir/Conversion/LLVMCommon/Pattern.h      |  2 +-
 mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td   | 27 --------------
 .../Conversion/AsyncToLLVM/AsyncToLLVM.cpp    |  4 +--
 .../GPUCommon/GPUToLLVMConversion.cpp         |  4 +--
 mlir/lib/Conversion/LLVMCommon/Pattern.cpp    |  4 +--
 mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp    |  8 ++---
 .../Transforms/SparseTensorConversion.cpp     |  2 +-
 mlir/lib/Target/LLVMIR/ModuleImport.cpp       |  2 +-
 .../AsyncToLLVM/convert-coro-to-llvm.mlir     |  2 +-
 .../AsyncToLLVM/convert-runtime-to-llvm.mlir  |  2 +-
 ...ower-launch-func-to-gpu-runtime-calls.mlir |  2 +-
 .../Conversion/GPUToVulkan/invoke-vulkan.mlir |  2 +-
 .../GPUToVulkan/typed-pointers.mlir           |  2 +-
 .../convert-dynamic-memref-ops.mlir           | 14 ++++----
 .../convert-static-memref-ops.mlir            |  8 ++---
 .../MemRefToLLVM/memref-to-llvm.mlir          |  6 ++--
 .../MemRefToLLVM/typed-pointers.mlir          |  4 +--
 mlir/test/Dialect/GPU/ops.mlir                |  2 +-
 mlir/test/Dialect/LLVMIR/callgraph.mlir       |  4 +--
 mlir/test/Dialect/LLVMIR/canonicalize.mlir    |  2 +-
 mlir/test/Dialect/LLVMIR/invalid.mlir         |  6 ++--
 mlir/test/Dialect/LLVMIR/mem2reg.mlir         | 10 +++---
 .../LLVMIR/roundtrip-typed-pointers.mlir      |  8 ++---
 mlir/test/Dialect/LLVMIR/roundtrip.mlir       |  8 ++---
 .../test/Dialect/SparseTensor/conversion.mlir |  2 +-
 .../SparseTensor/convert_dense2sparse.mlir    |  8 ++---
 .../Dialect/SparseTensor/sparse_concat.mlir   |  6 ++--
 .../SparseTensor/sparse_fill_zero.mlir        |  2 +-
 mlir/test/Target/LLVMIR/Import/constant.ll    |  6 ++--
 mlir/test/Target/LLVMIR/Import/exception.ll   |  4 +--
 .../test/Target/LLVMIR/Import/instructions.ll |  2 +-
 .../Target/LLVMIR/Import/zeroinitializer.ll   |  2 +-
 .../test/Target/LLVMIR/llvmir-intrinsics.mlir |  8 ++---
 mlir/test/Target/LLVMIR/llvmir.mlir           |  4 +--
 .../omptarget-declare-target-llvm-host.mlir   | 34 +++++++++---------
 .../test/Transforms/test-convert-call-op.mlir |  2 +-
 .../FuncToLLVM/TestConvertCallOp.cpp          |  2 +-
 43 files changed, 134 insertions(+), 160 deletions(-)

diff --git a/flang/lib/Optimizer/CodeGen/CodeGen.cpp b/flang/lib/Optimizer/CodeGen/CodeGen.cpp
index 6a6a10f632648..9d92086f8d709 100644
--- a/flang/lib/Optimizer/CodeGen/CodeGen.cpp
+++ b/flang/lib/Optimizer/CodeGen/CodeGen.cpp
@@ -1150,7 +1150,7 @@ computeElementDistance(mlir::Location loc, mlir::Type ptrTy, mlir::Type idxTy,
   // *)0 + 1)' trick for all types. The generated instructions are optimized
   // into constant by the first pass of InstCombine, so it should not be a
   // performance issue.
-  auto nullPtr = rewriter.create<mlir::LLVM::NullOp>(loc, ptrTy);
+  auto nullPtr = rewriter.create<mlir::LLVM::ZeroOp>(loc, ptrTy);
   auto gep = rewriter.create<mlir::LLVM::GEPOp>(
       loc, ptrTy, nullPtr, llvm::ArrayRef<mlir::LLVM::GEPArg>{1});
   return rewriter.create<mlir::LLVM::PtrToIntOp>(loc, idxTy, gep);
@@ -1431,7 +1431,7 @@ struct EmboxCommonConversion : public FIROpConversion<OP> {
             name, Fortran::semantics::typeInfoBuiltinModule))
       fir::emitFatalError(
           loc, "runtime derived type info descriptor was not generated");
-    return rewriter.create<mlir::LLVM::NullOp>(
+    return rewriter.create<mlir::LLVM::ZeroOp>(
         loc, ::getVoidPtrType(mod.getContext()));
   }
 
@@ -1474,7 +1474,7 @@ struct EmboxCommonConversion : public FIROpConversion<OP> {
           } else {
             // Unlimited polymorphic type descriptor with no record type. Set
             // type descriptor address to a clean state.
-            typeDesc = rewriter.create<mlir::LLVM::NullOp>(
+            typeDesc = rewriter.create<mlir::LLVM::ZeroOp>(
                 loc, ::getVoidPtrType(mod.getContext()));
           }
         } else {
@@ -3407,7 +3407,7 @@ struct ZeroOpConversion : public FIROpConversion<fir::ZeroOp> {
                   mlir::ConversionPatternRewriter &rewriter) const override {
     mlir::Type ty = convertType(zero.getType());
     if (ty.isa<mlir::LLVM::LLVMPointerType>()) {
-      rewriter.replaceOpWithNewOp<mlir::LLVM::NullOp>(zero, ty);
+      rewriter.replaceOpWithNewOp<mlir::LLVM::ZeroOp>(zero, ty);
     } else if (ty.isa<mlir::IntegerType>()) {
       rewriter.replaceOpWithNewOp<mlir::LLVM::ConstantOp>(
           zero, ty, mlir::IntegerAttr::get(ty, 0));
@@ -3470,7 +3470,7 @@ struct IsPresentOpConversion : public FIROpConversion<fir::IsPresentOp> {
 };
 
 /// Create value signaling an absent optional argument in a call, e.g.
-/// `fir.absent !fir.ref<i64>` -->  `llvm.mlir.null : !llvm.ptr<i64>`
+/// `fir.absent !fir.ref<i64>` -->  `llvm.mlir.zero : !llvm.ptr<i64>`
 struct AbsentOpConversion : public FIROpConversion<fir::AbsentOp> {
   using FIROpConversion::FIROpConversion;
 
@@ -3485,11 +3485,11 @@ struct AbsentOpConversion : public FIROpConversion<fir::AbsentOp> {
       assert(!structTy.isOpaque() && !structTy.getBody().empty());
       auto undefStruct = rewriter.create<mlir::LLVM::UndefOp>(loc, ty);
       auto nullField =
-          rewriter.create<mlir::LLVM::NullOp>(loc, structTy.getBody()[0]);
+          rewriter.create<mlir::LLVM::ZeroOp>(loc, structTy.getBody()[0]);
       rewriter.replaceOpWithNewOp<mlir::LLVM::InsertValueOp>(
           absent, undefStruct, nullField, 0);
     } else {
-      rewriter.replaceOpWithNewOp<mlir::LLVM::NullOp>(absent, ty);
+      rewriter.replaceOpWithNewOp<mlir::LLVM::ZeroOp>(absent, ty);
     }
     return mlir::success();
   }
diff --git a/flang/test/Fir/convert-to-llvm.fir b/flang/test/Fir/convert-to-llvm.fir
index 52716afe3198d..e39f13ac98268 100644
--- a/flang/test/Fir/convert-to-llvm.fir
+++ b/flang/test/Fir/convert-to-llvm.fir
@@ -145,7 +145,7 @@ func.func @zero_test_ptr() {
   return
 }
 
-// CHECK: %{{.*}} = llvm.mlir.null : !llvm.ptr<f32>
+// CHECK: %{{.*}} = llvm.mlir.zero : !llvm.ptr<f32>
 // CHECK-NOT: fir.zero_bits
 
 // -----
@@ -201,7 +201,7 @@ func.func @test_alloc_and_freemem_one() {
 }
 
 // CHECK-LABEL:  llvm.func @test_alloc_and_freemem_one() {
-// CHECK-NEXT:    %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<i32>
+// CHECK-NEXT:    %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<i32>
 // CHECK-NEXT:    %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK-NEXT:    %[[N:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<i32> to i64
 // CHECK-NEXT:    llvm.call @malloc(%[[N]])
@@ -220,7 +220,7 @@ func.func @test_alloc_and_freemem_several() {
 }
 
 // CHECK-LABEL:  llvm.func @test_alloc_and_freemem_several() {
-// CHECK: [[NULL:%.*]]  = llvm.mlir.null : !llvm.ptr<array<100 x f32>>
+// CHECK: [[NULL:%.*]]  = llvm.mlir.zero : !llvm.ptr<array<100 x f32>>
 // CHECK: [[PTR:%.*]]  = llvm.getelementptr [[NULL]][{{.*}}] : (!llvm.ptr<array<100 x f32>>) -> !llvm.ptr<array<100 x f32>>
 // CHECK: [[N:%.*]]  = llvm.ptrtoint [[PTR]] : !llvm.ptr<array<100 x f32>> to i64
 // CHECK: [[MALLOC:%.*]] = llvm.call @malloc([[N]])
@@ -238,7 +238,7 @@ func.func @test_with_shape(%ncols: index, %nrows: index) {
 
 // CHECK-LABEL: llvm.func @test_with_shape
 // CHECK-SAME: %[[NCOLS:.*]]: i64, %[[NROWS:.*]]: i64
-// CHECK:   %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<f32>
+// CHECK:   %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<f32>
 // CHECK:   %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK:   %[[FOUR:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<f32> to i64
 // CHECK:   %[[DIM1_SIZE:.*]] = llvm.mul %[[FOUR]], %[[NCOLS]]  : i64
@@ -258,7 +258,7 @@ func.func @test_string_with_shape(%len: index, %nelems: index) {
 
 // CHECK-LABEL: llvm.func @test_string_with_shape
 // CHECK-SAME: %[[LEN:.*]]: i64, %[[NELEMS:.*]]: i64)
-// CHECK:   %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK:   %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:   %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK:   %[[ONE:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<i8> to i64
 // CHECK:   %[[LEN_SIZE:.*]] = llvm.mul %[[ONE]], %[[LEN]]  : i64
@@ -750,7 +750,7 @@ func.func @convert_from_i1(%arg0 : i1) {
 
 // CHECK-LABEL: convert_from_i1(
 // CHECK-SAME: %[[ARG0:.*]]: i1
-// CHECK:        %{{.*}} = llvm.zext %[[ARG0]] : i1 to i32 
+// CHECK:        %{{.*}} = llvm.zext %[[ARG0]] : i1 to i32
 
 // -----
 
@@ -1403,7 +1403,7 @@ func.func @test_absent_i64() -> () {
 }
 
 // CHECK-LABEL: @test_absent_i64
-// CHECK-NEXT:  %{{.*}} = llvm.mlir.null : !llvm.ptr<i64>
+// CHECK-NEXT:  %{{.*}} = llvm.mlir.zero : !llvm.ptr<i64>
 // CHECK-NEXT:  llvm.return
 // CHECK-NEXT:  }
 
@@ -1412,7 +1412,7 @@ func.func @test_absent_box() -> () {
   return
 }
 // CHECK-LABEL: @test_absent_box
-// CHECK-NEXT:  %{{.*}} = llvm.mlir.null : !llvm.ptr<struct<(ptr<f32>, i64, i32, i8, i8, i8, i8, array<1 x array<3 x i64>>)>>
+// CHECK-NEXT:  %{{.*}} = llvm.mlir.zero : !llvm.ptr<struct<(ptr<f32>, i64, i32, i8, i8, i8, i8, array<1 x array<3 x i64>>)>>
 // CHECK-NEXT:  llvm.return
 // CHECK-NEXT:  }
 
@@ -1442,7 +1442,7 @@ func.func @absent() -> i1 {
 
 // CHECK-LABEL: @absent
 // CHECK-SAME:  () -> i1
-// CHECK-NEXT:  %[[ptr:.*]] = llvm.mlir.null : !llvm.ptr<i64>
+// CHECK-NEXT:  %[[ptr:.*]] = llvm.mlir.zero : !llvm.ptr<i64>
 // CHECK-NEXT:  %[[ret_val:.*]] = llvm.call @is_present(%[[ptr]]) : (!llvm.ptr<i64>) -> i1
 // CHECK-NEXT:  llvm.return %[[ret_val]] : i1
 
@@ -1525,7 +1525,7 @@ func.func @box_tdesc(%arg0: !fir.box<!fir.type<dtdesc{a:i32}>>) {
 
 // CHECK-LABEL: llvm.func @box_tdesc(
 // CHECK-SAME:                       %[[ARG0:.*]]: !llvm.ptr<struct<(ptr<struct<"dtdesc", (i{{.*}})>>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, ptr<i{{.*}}>, array<1 x i{{.*}}>)>>) {
-// CHECK:         %[[GEP:.*]] = llvm.getelementptr %[[ARG0]][0, 7] : (!llvm.ptr<struct<(ptr<struct<"dtdesc", (i{{.*}})>>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, ptr<i{{.*}}>, array<1 x i{{.*}}>)>>) -> !llvm.ptr<ptr<i8>> 
+// CHECK:         %[[GEP:.*]] = llvm.getelementptr %[[ARG0]][0, 7] : (!llvm.ptr<struct<(ptr<struct<"dtdesc", (i{{.*}})>>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, ptr<i{{.*}}>, array<1 x i{{.*}}>)>>) -> !llvm.ptr<ptr<i8>>
 // CHECK:         %[[LOAD:.*]] = llvm.load %[[GEP]] : !llvm.ptr<ptr<i{{.*}}>>
 
 // -----
@@ -1547,7 +1547,7 @@ func.func @embox0(%arg0: !fir.ref<!fir.array<100xi32>>) {
 // CHECK:         %[[C1:.*]] = llvm.mlir.constant(1 : i32) : i32
 // CHECK:         %[[ALLOCA:.*]] = llvm.alloca %[[C1]] x !llvm.struct<(ptr<array<100 x i32>>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}})> {alignment = 8 : i64} : (i32) -> !llvm.ptr<struct<(ptr<array<100 x i32>>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}})>>
 // CHECK:         %[[TYPE_CODE:.*]] = llvm.mlir.constant(9 : i32) : i32
-// CHECK:         %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<i32>
+// CHECK:         %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<i32>
 // CHECK:         %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK:         %[[I64_ELEM_SIZE:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<i32> to i64
 // CHECK:         %[[DESC:.*]] = llvm.mlir.undef : !llvm.struct<(ptr<array<100 x i32>>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}})>
@@ -1771,7 +1771,7 @@ func.func @xembox0(%arg0: !fir.ref<!fir.array<?xi32>>) {
 // CHECK:         %[[ALLOCA:.*]] = llvm.alloca %[[ALLOCA_SIZE]] x !llvm.struct<(ptr<i32>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, array<1 x array<3 x i64>>)> {alignment = 8 : i64} : (i32) -> !llvm.ptr<struct<(ptr<i32>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, array<1 x array<3 x i64>>)>>
 // CHECK:         %[[C0:.*]] = llvm.mlir.constant(0 : i64) : i64
 // CHECK:         %[[TYPE:.*]] = llvm.mlir.constant(9 : i32) : i32
-// CHECK:         %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<i32>
+// CHECK:         %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<i32>
 // CHECK:         %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK:         %[[ELEM_LEN_I64:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<i32> to i64
 // CHECK:         %[[BOX0:.*]] = llvm.mlir.undef : !llvm.struct<(ptr<i32>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, array<1 x array<3 x i64>>)>
@@ -1820,7 +1820,7 @@ func.func @xembox1(%arg0: !fir.ref<!fir.array<?x!fir.char<1, 10>>>) {
 
 // CHECK-LABEL: llvm.func @xembox1(%{{.*}}: !llvm.ptr<array<10 x i8>>) {
 // CHECK:         %[[C0:.*]] = llvm.mlir.constant(0 : i64) : i64
-// CHECK:         %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<array<10 x i8>>
+// CHECK:         %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<array<10 x i8>>
 // CHECK:         %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK:         %[[ELEM_LEN_I64:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<array<10 x i8>> to i64
 // CHECK:         %{{.*}} = llvm.insertvalue %[[ELEM_LEN_I64]], %{{.*}}[1] : !llvm.struct<(ptr<array<10 x i8>>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, array<1 x array<3 x i64>>)>
@@ -1870,7 +1870,7 @@ func.func private @_QPxb(!fir.box<!fir.array<?x?xf64>>)
 // CHECK:         %[[ARR_SIZE:.*]] = llvm.mul %[[ARR_SIZE_TMP1]], %[[N2]]  : i64
 // CHECK:         %[[ARR:.*]] = llvm.alloca %[[ARR_SIZE]] x f64 {bindc_name = "arr", in_type = !fir.array<?x?xf64>, operandSegmentSizes = array<i32: 0, 2>, uniq_name = "_QFsbEarr"} : (i64) -> !llvm.ptr<f64>
 // CHECK:         %[[TYPE_CODE:.*]] = llvm.mlir.constant(28 : i32) : i32
-// CHECK:         %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<f64>
+// CHECK:         %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<f64>
 // CHECK:         %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK:         %[[ELEM_LEN_I64:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<f64> to i64
 // CHECK:         %[[BOX0:.*]] = llvm.mlir.undef : !llvm.struct<(ptr<f64>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, array<2 x array<3 x i64>>)>
@@ -1949,7 +1949,7 @@ func.func private @_QPtest_dt_callee(%arg0: !fir.box<!fir.array<?xi32>>)
 // CHECK:         %[[ALLOCA_SIZE_X:.*]] = llvm.mlir.constant(1 : i64) : i64
 // CHECK:         %[[X:.*]] = llvm.alloca %[[ALLOCA_SIZE_X]] x !llvm.array<20 x struct<"_QFtest_dt_sliceTt", (i32, i32)>> {bindc_name = "x", in_type = !fir.array<20x!fir.type<_QFtest_dt_sliceTt{i:i32,j:i32}>>, operandSegmentSizes = array<i32: 0, 0>, uniq_name = "_QFtest_dt_sliceEx"} : (i64) -> !llvm.ptr<array<20 x struct<"_QFtest_dt_sliceTt", (i32, i32)>>>
 // CHECK:         %[[TYPE_CODE:.*]] = llvm.mlir.constant(9 : i32) : i32
-// CHECK:         %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<i32>
+// CHECK:         %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<i32>
 // CHECK:         %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 // CHECK:         %[[ELEM_LEN_I64:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<i32> to i64
 // CHECK:         %[[BOX0:.*]] = llvm.mlir.undef : !llvm.struct<(ptr<i32>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, array<1 x array<3 x i64>>)>
@@ -1969,7 +1969,7 @@ func.func private @_QPtest_dt_callee(%arg0: !fir.box<!fir.array<?xi32>>)
 // CHECK:         %[[BOX6:.*]] = llvm.insertvalue %[[F18ADDENDUM_I8]], %[[BOX5]][6] : !llvm.struct<(ptr<i32>, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, i{{.*}}, array<1 x array<3 x i64>>)>
 // CHECK:         %[[ZERO:.*]] = llvm.mlir.constant(0 : i64) : i64
 // CHECK:         %[[ONE:.*]] = llvm.mlir.constant(1 : i64) : i64
-// CHECK:         %[[ELE_TYPE:.*]] = llvm.mlir.null : !llvm.ptr<struct<"_QFtest_dt_sliceTt", (i32, i32)>>
+// CHECK:         %[[ELE_TYPE:.*]] = llvm.mlir.zero : !llvm.ptr<struct<"_QFtest_dt_sliceTt", (i32, i32)>>
 // CHECK:         %[[GEP_DTYPE_SIZE:.*]] = llvm.getelementptr %[[ELE_TYPE]][1] : (!llvm.ptr<struct<"_QFtest_dt_sliceTt", (i32, i32)>>) -> !llvm.ptr<struct<"_QFtest_dt_sliceTt", (i32, i32)>>
 // CHECK:         %[[PTRTOINT_DTYPE_SIZE:.*]] = llvm.ptrtoint %[[GEP_DTYPE_SIZE]] : !llvm.ptr<struct<"_QFtest_dt_sliceTt", (i32, i32)>> to i64
 // CHECK:         %[[ADJUSTED_OFFSET:.*]] = llvm.sub %[[C1]], %[[ONE]]  : i64
@@ -2261,7 +2261,7 @@ func.func @test_rebox_1(%arg0: !fir.box<!fir.array<?x?xf32>>) {
 //CHECK:    %[[SIX:.*]] = llvm.mlir.constant(6 : index) : i64
 //CHECK:    %[[EIGHTY:.*]] = llvm.mlir.constant(80 : index) : i64
 //CHECK:    %[[FLOAT_TYPE:.*]] = llvm.mlir.constant(27 : i32) : i32
-//CHECK:    %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<f32>
+//CHECK:    %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<f32>
 //CHECK:    %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 //CHECK:    %[[ELEM_SIZE_I64:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<f32> to i64
 //CHECK:    %[[RBOX:.*]] = llvm.mlir.undef : !llvm.struct<(ptr<f32>, i64, i32, i8, i8, i8, i8, array<1 x array<3 x i64>>)>
@@ -2334,7 +2334,7 @@ func.func @foo(%arg0: !fir.box<!fir.array<?x!fir.type<t{i:i32,c:!fir.char<1,10>}
 //CHECK:   %[[COMPONENT_OFFSET_1:.*]] = llvm.mlir.constant(1 : i64) : i64
 //CHECK:   %[[ELEM_COUNT:.*]] = llvm.mlir.constant(7 : i64) : i64
 //CHECK:   %[[TYPE_CHAR:.*]] = llvm.mlir.constant(40 : i32) : i32
-//CHECK:   %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+//CHECK:   %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 //CHECK:   %[[GEP:.*]] = llvm.getelementptr %[[NULL]][1]
 //CHECK:   %[[CHAR_SIZE:.*]] = llvm.ptrtoint %[[GEP]] : !llvm.ptr<i8> to i64
 //CHECK:   %[[ELEM_SIZE:.*]] = llvm.mul %[[CHAR_SIZE]], %[[ELEM_COUNT]]
diff --git a/flang/test/Fir/embox-char.fir b/flang/test/Fir/embox-char.fir
index 8a7ef396abab0..2e8a826e0b8d5 100644
--- a/flang/test/Fir/embox-char.fir
+++ b/flang/test/Fir/embox-char.fir
@@ -40,7 +40,7 @@
 // CHECK:           %[[VAL_30_ST0:.*]] = llvm.load %[[VAL_29]] : !llvm.ptr<i64>
 // CHECK:           %[[VAL_31_LEN:.*]] = llvm.sdiv %[[VAL_16_BYTESIZE]], %[[VAL_13_WIDTH]]  : i64
 // CHECK:           %[[VAL_32:.*]] = llvm.mlir.constant(44 : i32) : i32
-// CHECK:           %[[VAL_33:.*]] = llvm.mlir.null : !llvm.ptr<i32>
+// CHECK:           %[[VAL_33:.*]] = llvm.mlir.zero : !llvm.ptr<i32>
 // CHECK:           %[[VAL_34:.*]] = llvm.getelementptr %[[VAL_33]][1] : (!llvm.ptr<i32>) -> !llvm.ptr<i32>
 // CHECK:           %[[VAL_35:.*]] = llvm.ptrtoint %[[VAL_34]] : !llvm.ptr<i32> to i64
 // CHECK:           %[[VAL_36_BYTESIZE:.*]] = llvm.mul %[[VAL_35]], %[[VAL_31_LEN]]  : i64
@@ -137,7 +137,7 @@ func.func @test_char4(%arg0: !fir.ref<!fir.box<!fir.heap<!fir.array<?x?x!fir.cha
 // CHECK:           %[[VAL_29:.*]] = llvm.getelementptr %[[VAL_10]][0, 7, %[[VAL_11]], 2] : (!llvm.ptr<struct<(ptr<i8>, i64, i32, i8, i8, i8, i8, array<2 x array<3 x i64>>)>>, i64) -> !llvm.ptr<i64>
 // CHECK:           %[[VAL_30_ST0:.*]] = llvm.load %[[VAL_29]] : !llvm.ptr<i64>
 // CHECK:           %[[VAL_32:.*]] = llvm.mlir.constant(40 : i32) : i32
-// CHECK:           %[[VAL_33:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK:           %[[VAL_33:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:           %[[VAL_34:.*]] = llvm.getelementptr %[[VAL_33]][1] : (!llvm.ptr<i8>) -> !llvm.ptr<i8>
 // CHECK:           %[[VAL_35:.*]] = llvm.ptrtoint %[[VAL_34]] : !llvm.ptr<i8> to i64
 // CHECK:           %[[VAL_36_BYTESIZE:.*]] = llvm.mul %[[VAL_35]], %[[VAL_16_BYTESIZE]]  : i64
diff --git a/flang/test/Fir/embox-substring.fir b/flang/test/Fir/embox-substring.fir
index fd0b5923df0ed..4e2395bc7f345 100644
--- a/flang/test/Fir/embox-substring.fir
+++ b/flang/test/Fir/embox-substring.fir
@@ -30,7 +30,7 @@ func.func private @dump(!fir.box<!fir.array<2x!fir.char<1>>>)
 // CHECK-SAME:                                  %[[VAL_1:.*]]: i64) {
 // CHECK:           %[[VAL_5:.*]] = llvm.mlir.constant(1 : index) : i64
 // CHECK:           llvm.getelementptr
-// CHECK:           %[[VAL_28:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK:           %[[VAL_28:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:           %[[VAL_29:.*]] = llvm.getelementptr %[[VAL_28]][1] : (!llvm.ptr<i8>) -> !llvm.ptr<i8>
 // CHECK:           %[[VAL_30:.*]] = llvm.ptrtoint %[[VAL_29]] : !llvm.ptr<i8> to i64
 // CHECK:           %[[VAL_31:.*]] = llvm.mul %[[VAL_30]], %[[VAL_1]]  : i64
diff --git a/flang/test/Fir/tbaa.fir b/flang/test/Fir/tbaa.fir
index 66bd41bad18e7..f8a52b2e98db0 100644
--- a/flang/test/Fir/tbaa.fir
+++ b/flang/test/Fir/tbaa.fir
@@ -205,7 +205,7 @@ module {
 
 // CHECK-LABEL:   llvm.mlir.global internal @_QFEx() {addr_space = 0 : i32} : !llvm.struct<(ptr<struct<()>>, i64, i32, i8, i8, i8, i8, array<1 x array<3 x i64>>, ptr<i8>, array<1 x i64>)> {
 // CHECK:           %[[VAL_0:.*]] = llvm.mlir.constant(0 : index) : i64
-// CHECK:           %[[VAL_1:.*]] = llvm.mlir.null : !llvm.ptr<struct<()>>
+// CHECK:           %[[VAL_1:.*]] = llvm.mlir.zero : !llvm.ptr<struct<()>>
 // CHECK:           %[[VAL_2:.*]] = llvm.mlir.constant(0 : i64) : i64
 // CHECK:           %[[VAL_3:.*]] = llvm.mlir.constant(-1 : i32) : i32
 // CHECK:           %[[VAL_4:.*]] = llvm.mlir.undef : !llvm.struct<(ptr<struct<()>>, i64, i32, i8, i8, i8, i8, array<1 x array<3 x i64>>, ptr<i8>, array<1 x i64>)>
@@ -223,7 +223,7 @@ module {
 // CHECK:           %[[VAL_16:.*]] = llvm.mlir.constant(1 : i32) : i32
 // CHECK:           %[[VAL_17:.*]] = llvm.trunc %[[VAL_16]] : i32 to i8
 // CHECK:           %[[VAL_18:.*]] = llvm.insertvalue %[[VAL_17]], %[[VAL_15]][6] : !llvm.struct<(ptr<struct<()>>, i64, i32, i8, i8, i8, i8, array<1 x array<3 x i64>>, ptr<i8>, array<1 x i64>)>
-// CHECK:           %[[VAL_19:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK:           %[[VAL_19:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:           %[[VAL_20:.*]] = llvm.bitcast %[[VAL_19]] : !llvm.ptr<i8> to !llvm.ptr<i8>
 // CHECK:           %[[VAL_21:.*]] = llvm.insertvalue %[[VAL_20]], %[[VAL_18]][8] : !llvm.struct<(ptr<struct<()>>, i64, i32, i8, i8, i8, i8, array<1 x array<3 x i64>>, ptr<i8>, array<1 x i64>)>
 // CHECK:           %[[VAL_22:.*]] = llvm.mlir.constant(0 : i64) : i64
diff --git a/mlir/docs/Dialects/LLVM.md b/mlir/docs/Dialects/LLVM.md
index fa5ce630ad43b..796c3a7b76844 100644
--- a/mlir/docs/Dialects/LLVM.md
+++ b/mlir/docs/Dialects/LLVM.md
@@ -103,10 +103,10 @@ Some value kinds in LLVM IR, such as constants and undefs, are uniqued in
 context and used directly in relevant operations. MLIR does not support such
 values for thread-safety and concept parsimony reasons. Instead, regular values
 are produced by dedicated operations that have the corresponding semantics:
-[`llvm.mlir.constant`](#llvmmlirconstant-mlirllvmconstantop),
-[`llvm.mlir.undef`](#llvmmlirundef-mlirllvmundefop),
-[`llvm.mlir.poison`](#llvmmlirpoison-mlirllvmpoisonop),
-[`llvm.mlir.null`](#llvmmlirnull-mlirllvmnullop). Note how these operations are
+[`llvm.mlir.constant`](#llvmmlirconstant-llvmconstantop),
+[`llvm.mlir.undef`](#llvmmlirundef-llvmundefop),
+[`llvm.mlir.poison`](#llvmmlirpoison-llvmpoisonop),
+[`llvm.mlir.zero`](#llvmmlirzero-llvmzeroop). Note how these operations are
 prefixed with `mlir.` to indicate that they don't belong to LLVM IR but are only
 necessary to model it in MLIR. The values produced by these operations are
 usable just like any other value.
@@ -118,11 +118,12 @@ Examples:
 // by a float.
 %0 = llvm.mlir.undef : !llvm.struct<(i32, f32)>
 
-// Null pointer to i8.
-%1 = llvm.mlir.null : !llvm.ptr<i8>
+// Null pointer.
+%1 = llvm.mlir.zero : !llvm.ptr
 
-// Null pointer to a function with signature void().
-%2 = llvm.mlir.null : !llvm.ptr<func<void ()>>
+// Create an zero initialized value of structure type with a 32-bit integer
+// followed by a float.
+%2 = llvm.mlir.zero :  !llvm.struct<(i32, f32)>
 
 // Constant 42 as i32.
 %3 = llvm.mlir.constant(42 : i32) : i32
diff --git a/mlir/include/mlir/Conversion/LLVMCommon/Pattern.h b/mlir/include/mlir/Conversion/LLVMCommon/Pattern.h
index 92f4025ffffff..aea6c38a441d3 100644
--- a/mlir/include/mlir/Conversion/LLVMCommon/Pattern.h
+++ b/mlir/include/mlir/Conversion/LLVMCommon/Pattern.h
@@ -89,7 +89,7 @@ class ConvertToLLVMPattern : public ConversionPattern {
   /// `strides[1]` = llvm.mlir.constant(1 : index) : i64
   /// `strides[0]` = `sizes[0]`
   /// %size        = llvm.mul `sizes[0]`, `sizes[1]` : i64
-  /// %nullptr     = llvm.mlir.null : !llvm.ptr<f32>
+  /// %nullptr     = llvm.mlir.zero : !llvm.ptr<f32>
   /// %gep         = llvm.getelementptr %nullptr[%size]
   ///                  : (!llvm.ptr<f32>, i64) -> !llvm.ptr<f32>
   /// `sizeBytes`  = llvm.ptrtoint %gep : !llvm.ptr<f32> to i64
diff --git a/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td b/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td
index c0216d1971e58..e4486eb36e51a 100644
--- a/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td
+++ b/mlir/include/mlir/Dialect/LLVMIR/LLVMOps.td
@@ -1438,33 +1438,6 @@ def LLVM_LLVMFuncOp : LLVM_Op<"func", [
   let hasRegionVerifier = 1;
 }
 
-def LLVM_NullOp
-    : LLVM_Op<"mlir.null", [Pure]>,
-      LLVM_Builder<"$res = llvm::ConstantPointerNull::get("
-                   "    cast<llvm::PointerType>($_resultType));"> {
-  let summary = "Defines a value containing a null pointer to LLVM type.";
-  let description = [{
-    Unlike LLVM IR, MLIR does not have first-class null pointers. They must be
-    explicitly created as SSA values using `llvm.mlir.null`. This operation has
-    no operands or attributes, and returns a null value of a wrapped LLVM IR
-    pointer type.
-
-    Examples:
-
-    ```mlir
-    // Null pointer to i8.
-    %0 = llvm.mlir.null : !llvm.ptr<i8>
-
-    // Null pointer to a function with signature void().
-    %1 = llvm.mlir.null : !llvm.ptr<func<void ()>>
-    ```
-  }];
-
-  let results = (outs LLVM_AnyPointer:$res);
-  let builders = [LLVM_OneResultOpBuilder];
-  let assemblyFormat = "attr-dict `:` qualified(type($res))";
-}
-
 def LLVM_NoneTokenOp
     : LLVM_Op<"mlir.none", [Pure]> {
   let summary = "Defines a value containing an empty token to LLVM type.";
diff --git a/mlir/lib/Conversion/AsyncToLLVM/AsyncToLLVM.cpp b/mlir/lib/Conversion/AsyncToLLVM/AsyncToLLVM.cpp
index 1c3fbe8057c5b..d9ea60a6749d9 100644
--- a/mlir/lib/Conversion/AsyncToLLVM/AsyncToLLVM.cpp
+++ b/mlir/lib/Conversion/AsyncToLLVM/AsyncToLLVM.cpp
@@ -421,7 +421,7 @@ class CoroIdOpConversion : public AsyncOpConversionPattern<CoroIdOp> {
     // Constants for initializing coroutine frame.
     auto constZero =
         rewriter.create<LLVM::ConstantOp>(loc, rewriter.getI32Type(), 0);
-    auto nullPtr = rewriter.create<LLVM::NullOp>(loc, ptrType);
+    auto nullPtr = rewriter.create<LLVM::ZeroOp>(loc, ptrType);
 
     // Get coroutine id: @llvm.coro.id.
     rewriter.replaceOpWithNewOp<LLVM::CoroIdOp>(
@@ -677,7 +677,7 @@ class RuntimeCreateOpLowering : public ConvertOpToLLVMPattern<RuntimeCreateOp> {
 
         // %Size = getelementptr %T* null, int 1
         // %SizeI = ptrtoint %T* %Size to i64
-        auto nullPtr = rewriter.create<LLVM::NullOp>(loc, storagePtrType);
+        auto nullPtr = rewriter.create<LLVM::ZeroOp>(loc, storagePtrType);
         auto gep =
             rewriter.create<LLVM::GEPOp>(loc, storagePtrType, storedType,
                                          nullPtr, ArrayRef<LLVM::GEPArg>{1});
diff --git a/mlir/lib/Conversion/GPUCommon/GPUToLLVMConversion.cpp b/mlir/lib/Conversion/GPUCommon/GPUToLLVMConversion.cpp
index eddf3e9a47d0b..b6d9ec6e013b4 100644
--- a/mlir/lib/Conversion/GPUCommon/GPUToLLVMConversion.cpp
+++ b/mlir/lib/Conversion/GPUCommon/GPUToLLVMConversion.cpp
@@ -1149,7 +1149,7 @@ LogicalResult ConvertLaunchFuncOpToGpuRuntimeCallPattern::matchAndRewrite(
           : adaptor.getAsyncDependencies().front();
   // Create array of pointers to kernel arguments.
   auto kernelParams = generateParamsArray(launchOp, adaptor, rewriter);
-  auto nullpointer = rewriter.create<LLVM::NullOp>(loc, llvmPointerPointerType);
+  auto nullpointer = rewriter.create<LLVM::ZeroOp>(loc, llvmPointerPointerType);
   Value dynamicSharedMemorySize = launchOp.getDynamicSharedMemorySize()
                                       ? launchOp.getDynamicSharedMemorySize()
                                       : zero;
@@ -1211,7 +1211,7 @@ LogicalResult ConvertMemcpyOpToGpuRuntimeCallPattern::matchAndRewrite(
   Value numElements = getNumElements(rewriter, loc, memRefType, srcDesc);
 
   Type elementPtrType = getElementPtrType(memRefType);
-  Value nullPtr = rewriter.create<LLVM::NullOp>(loc, elementPtrType);
+  Value nullPtr = rewriter.create<LLVM::ZeroOp>(loc, elementPtrType);
   Value gepPtr = rewriter.create<LLVM::GEPOp>(
       loc, elementPtrType,
       typeConverter->convertType(memRefType.getElementType()), nullPtr,
diff --git a/mlir/lib/Conversion/LLVMCommon/Pattern.cpp b/mlir/lib/Conversion/LLVMCommon/Pattern.cpp
index e5519df9b0185..40d4c97975a6a 100644
--- a/mlir/lib/Conversion/LLVMCommon/Pattern.cpp
+++ b/mlir/lib/Conversion/LLVMCommon/Pattern.cpp
@@ -162,7 +162,7 @@ void ConvertToLLVMPattern::getMemRefDescriptorSizes(
     // Buffer size in bytes.
     Type elementType = typeConverter->convertType(memRefType.getElementType());
     Type elementPtrType = getTypeConverter()->getPointerType(elementType);
-    Value nullPtr = rewriter.create<LLVM::NullOp>(loc, elementPtrType);
+    Value nullPtr = rewriter.create<LLVM::ZeroOp>(loc, elementPtrType);
     Value gepPtr = rewriter.create<LLVM::GEPOp>(
         loc, elementPtrType, elementType, nullPtr, runningStride);
     size = rewriter.create<LLVM::PtrToIntOp>(loc, getIndexType(), gepPtr);
@@ -180,7 +180,7 @@ Value ConvertToLLVMPattern::getSizeInBytes(
   // which is a common pattern of getting the size of a type in bytes.
   Type llvmType = typeConverter->convertType(type);
   auto convertedPtrType = getTypeConverter()->getPointerType(llvmType);
-  auto nullPtr = rewriter.create<LLVM::NullOp>(loc, convertedPtrType);
+  auto nullPtr = rewriter.create<LLVM::ZeroOp>(loc, convertedPtrType);
   auto gep = rewriter.create<LLVM::GEPOp>(loc, convertedPtrType, llvmType,
                                           nullPtr, ArrayRef<LLVM::GEPArg>{1});
   return rewriter.create<LLVM::PtrToIntOp>(loc, getIndexType(), gep);
diff --git a/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp b/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
index 1cf91bde28183..2e0b2582eee96 100644
--- a/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
+++ b/mlir/lib/Dialect/LLVMIR/IR/LLVMDialect.cpp
@@ -195,12 +195,12 @@ OpFoldResult ICmpOp::fold(FoldAdaptor adaptor) {
                             getPredicate() == ICmpPredicate::eq);
 
   // cmpi(eq/ne, alloca, null) -> false/true
-  if (getLhs().getDefiningOp<AllocaOp>() && getRhs().getDefiningOp<NullOp>())
+  if (getLhs().getDefiningOp<AllocaOp>() && getRhs().getDefiningOp<ZeroOp>())
     return getBoolAttribute(getType(), getContext(),
                             getPredicate() == ICmpPredicate::ne);
 
   // cmpi(eq/ne, null, alloca) -> cmpi(eq/ne, alloca, null)
-  if (getLhs().getDefiningOp<NullOp>() && getRhs().getDefiningOp<AllocaOp>()) {
+  if (getLhs().getDefiningOp<ZeroOp>() && getRhs().getDefiningOp<AllocaOp>()) {
     Value lhs = getLhs();
     Value rhs = getRhs();
     getLhsMutable().assign(rhs);
@@ -1466,8 +1466,8 @@ LogicalResult LandingpadOp::verify() {
                << "global addresses expected as operand to "
                   "bitcast used in clauses for landingpad";
       }
-      // NullOp and AddressOfOp allowed
-      if (value.getDefiningOp<NullOp>())
+      // ZeroOp and AddressOfOp allowed
+      if (value.getDefiningOp<ZeroOp>())
         continue;
       if (value.getDefiningOp<AddressOfOp>())
         continue;
diff --git a/mlir/lib/Dialect/SparseTensor/Transforms/SparseTensorConversion.cpp b/mlir/lib/Dialect/SparseTensor/Transforms/SparseTensorConversion.cpp
index d75601e369a0d..894382cd7f37b 100644
--- a/mlir/lib/Dialect/SparseTensor/Transforms/SparseTensorConversion.cpp
+++ b/mlir/lib/Dialect/SparseTensor/Transforms/SparseTensorConversion.cpp
@@ -299,7 +299,7 @@ class NewCallParams final {
     assert(isInitialized() && "Must initialize before genNewCall");
     StringRef name = "newSparseTensor";
     params[kParamAction] = constantAction(builder, loc, action);
-    params[kParamPtr] = ptr ? ptr : builder.create<LLVM::NullOp>(loc, pTp);
+    params[kParamPtr] = ptr ? ptr : builder.create<LLVM::ZeroOp>(loc, pTp);
     return createFuncCall(builder, loc, name, pTp, params, EmitCInterface::On)
         .getResult(0);
   }
diff --git a/mlir/lib/Target/LLVMIR/ModuleImport.cpp b/mlir/lib/Target/LLVMIR/ModuleImport.cpp
index c6c30880d4f2c..3d93332c4c567 100644
--- a/mlir/lib/Target/LLVMIR/ModuleImport.cpp
+++ b/mlir/lib/Target/LLVMIR/ModuleImport.cpp
@@ -987,7 +987,7 @@ FailureOr<Value> ModuleImport::convertConstant(llvm::Constant *constant) {
   // Convert null pointer constants.
   if (auto *nullPtr = dyn_cast<llvm::ConstantPointerNull>(constant)) {
     Type type = convertType(nullPtr->getType());
-    return builder.create<NullOp>(loc, type).getResult();
+    return builder.create<ZeroOp>(loc, type).getResult();
   }
 
   // Convert none token constants.
diff --git a/mlir/test/Conversion/AsyncToLLVM/convert-coro-to-llvm.mlir b/mlir/test/Conversion/AsyncToLLVM/convert-coro-to-llvm.mlir
index fb15a2da2836b..8a611cf96f5b5 100644
--- a/mlir/test/Conversion/AsyncToLLVM/convert-coro-to-llvm.mlir
+++ b/mlir/test/Conversion/AsyncToLLVM/convert-coro-to-llvm.mlir
@@ -3,7 +3,7 @@
 // CHECK-LABEL: @coro_id
 func.func @coro_id() {
   // CHECK: %0 = llvm.mlir.constant(0 : i32) : i32
-  // CHECK: %1 = llvm.mlir.null : !llvm.ptr
+  // CHECK: %1 = llvm.mlir.zero : !llvm.ptr
   // CHECK: %2 = llvm.intr.coro.id %0, %1, %1, %1 : (i32, !llvm.ptr, !llvm.ptr, !llvm.ptr) -> !llvm.token
   %0 = async.coro.id
   return
diff --git a/mlir/test/Conversion/AsyncToLLVM/convert-runtime-to-llvm.mlir b/mlir/test/Conversion/AsyncToLLVM/convert-runtime-to-llvm.mlir
index 7ff5a2c4a490d..3672be91bbc07 100644
--- a/mlir/test/Conversion/AsyncToLLVM/convert-runtime-to-llvm.mlir
+++ b/mlir/test/Conversion/AsyncToLLVM/convert-runtime-to-llvm.mlir
@@ -9,7 +9,7 @@ func.func @create_token() {
 
 // CHECK-LABEL: @create_value
 func.func @create_value() {
-  // CHECK: %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr
+  // CHECK: %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr
   // CHECK: %[[OFFSET:.*]] = llvm.getelementptr %[[NULL]][1]
   // CHECK: %[[SIZE:.*]] = llvm.ptrtoint %[[OFFSET]]
   // CHECK: %[[VALUE:.*]] = call @mlirAsyncRuntimeCreateValue(%[[SIZE]])
diff --git a/mlir/test/Conversion/GPUCommon/lower-launch-func-to-gpu-runtime-calls.mlir b/mlir/test/Conversion/GPUCommon/lower-launch-func-to-gpu-runtime-calls.mlir
index 2cdc4e8dbb1ad..b7bcbc1262d82 100644
--- a/mlir/test/Conversion/GPUCommon/lower-launch-func-to-gpu-runtime-calls.mlir
+++ b/mlir/test/Conversion/GPUCommon/lower-launch-func-to-gpu-runtime-calls.mlir
@@ -52,7 +52,7 @@ module attributes {gpu.container_module} {
   // CHECK: llvm.getelementptr %[[MEMREF]][0, 4] : (!llvm.ptr) -> !llvm.ptr, !llvm.struct[[STRUCT_BODY:<.*>]]
   // CHECK: llvm.getelementptr %[[MEMREF]][0, 5] : (!llvm.ptr) -> !llvm.ptr, !llvm.struct[[STRUCT_BODY:<.*>]]
 
-  // CHECK: [[EXTRA_PARAMS:%.*]] = llvm.mlir.null : !llvm.ptr
+  // CHECK: [[EXTRA_PARAMS:%.*]] = llvm.mlir.zero : !llvm.ptr
 
   // CHECK: llvm.call @mgpuLaunchKernel([[FUNC]], [[C8]], [[C8]], [[C8]],
   // CHECK-SAME: [[C8]], [[C8]], [[C8]], [[C256]], [[STREAM]],
diff --git a/mlir/test/Conversion/GPUToVulkan/invoke-vulkan.mlir b/mlir/test/Conversion/GPUToVulkan/invoke-vulkan.mlir
index c77bf238c8ca2..f6da6d0a3be34 100644
--- a/mlir/test/Conversion/GPUToVulkan/invoke-vulkan.mlir
+++ b/mlir/test/Conversion/GPUToVulkan/invoke-vulkan.mlir
@@ -21,7 +21,7 @@ module attributes {gpu.container_module} {
   llvm.func @malloc(i64) -> !llvm.ptr
   llvm.func @foo() {
     %0 = llvm.mlir.constant(12 : index) : i64
-    %1 = llvm.mlir.null : !llvm.ptr
+    %1 = llvm.mlir.zero : !llvm.ptr
     %2 = llvm.mlir.constant(1 : index) : i64
     %3 = llvm.getelementptr %1[%2] : (!llvm.ptr, i64) -> !llvm.ptr, f32
     %4 = llvm.ptrtoint %3 : !llvm.ptr to i64
diff --git a/mlir/test/Conversion/GPUToVulkan/typed-pointers.mlir b/mlir/test/Conversion/GPUToVulkan/typed-pointers.mlir
index 67bd640e5d44c..2884b33750b32 100644
--- a/mlir/test/Conversion/GPUToVulkan/typed-pointers.mlir
+++ b/mlir/test/Conversion/GPUToVulkan/typed-pointers.mlir
@@ -21,7 +21,7 @@ module attributes {gpu.container_module} {
   llvm.func @malloc(i64) -> !llvm.ptr<i8>
   llvm.func @foo() {
     %0 = llvm.mlir.constant(12 : index) : i64
-    %1 = llvm.mlir.null : !llvm.ptr<f32>
+    %1 = llvm.mlir.zero : !llvm.ptr<f32>
     %2 = llvm.mlir.constant(1 : index) : i64
     %3 = llvm.getelementptr %1[%2] : (!llvm.ptr<f32>, i64) -> !llvm.ptr<f32>
     %4 = llvm.ptrtoint %3 : !llvm.ptr<f32> to i64
diff --git a/mlir/test/Conversion/MemRefToLLVM/convert-dynamic-memref-ops.mlir b/mlir/test/Conversion/MemRefToLLVM/convert-dynamic-memref-ops.mlir
index 447875506b1ed..ea6a235857e63 100644
--- a/mlir/test/Conversion/MemRefToLLVM/convert-dynamic-memref-ops.mlir
+++ b/mlir/test/Conversion/MemRefToLLVM/convert-dynamic-memref-ops.mlir
@@ -11,7 +11,7 @@ func.func @mixed_alloc(%arg0: index, %arg1: index) -> memref<?x42x?xf32> {
 //  CHECK-NEXT:  %[[one:.*]] = llvm.mlir.constant(1 : index) : i64
 //  CHECK-NEXT:  %[[st0:.*]] = llvm.mul %[[N]], %[[c42]] : i64
 //  CHECK-NEXT:  %[[sz:.*]] = llvm.mul %[[st0]], %[[M]] : i64
-//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.null : !llvm.ptr
+//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.zero : !llvm.ptr
 //  CHECK-NEXT:  %[[gep:.*]] = llvm.getelementptr %[[null]][%[[sz]]] : (!llvm.ptr, i64) -> !llvm.ptr, f32
 //  CHECK-NEXT:  %[[sz_bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr to i64
 //  CHECK-NEXT:  llvm.call @malloc(%[[sz_bytes]]) : (i64) -> !llvm.ptr
@@ -60,7 +60,7 @@ func.func @dynamic_alloc(%arg0: index, %arg1: index) -> memref<?x?xf32> {
 //   CHECK-DAG:  %[[N:.*]] = builtin.unrealized_conversion_cast %[[Narg]]
 //  CHECK-NEXT:  %[[one:.*]] = llvm.mlir.constant(1 : index) : i64
 //  CHECK-NEXT:  %[[sz:.*]] = llvm.mul %[[N]], %[[M]] : i64
-//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.null : !llvm.ptr
+//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.zero : !llvm.ptr
 //  CHECK-NEXT:  %[[gep:.*]] = llvm.getelementptr %[[null]][%[[sz]]] : (!llvm.ptr, i64) -> !llvm.ptr, f32
 //  CHECK-NEXT:  %[[sz_bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr to i64
 //  CHECK-NEXT:  llvm.call @malloc(%[[sz_bytes]]) : (i64) -> !llvm.ptr
@@ -128,7 +128,7 @@ func.func @stdlib_aligned_alloc(%N : index) -> memref<32x18xf32> {
 // ALIGNED-ALLOC-NEXT:  %[[sz2:.*]] = llvm.mlir.constant(18 : index) : i64
 // ALIGNED-ALLOC-NEXT:  %[[one:.*]] = llvm.mlir.constant(1 : index) : i64
 // ALIGNED-ALLOC-NEXT:  %[[num_elems:.*]] = llvm.mlir.constant(576 : index) : i64
-// ALIGNED-ALLOC-NEXT:  %[[null:.*]] = llvm.mlir.null : !llvm.ptr
+// ALIGNED-ALLOC-NEXT:  %[[null:.*]] = llvm.mlir.zero : !llvm.ptr
 // ALIGNED-ALLOC-NEXT:  %[[gep:.*]] = llvm.getelementptr %[[null]][%[[num_elems]]] : (!llvm.ptr, i64) -> !llvm.ptr, f32
 // ALIGNED-ALLOC-NEXT:  %[[bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr to i64
 // ALIGNED-ALLOC-NEXT:  %[[alignment:.*]] = llvm.mlir.constant(32 : index) : i64
@@ -570,7 +570,7 @@ func.func @memref_reshape(%input : memref<2x3xf32>, %shape : memref<?xindex>) {
 // ALIGNED-ALLOC-LABEL: @memref_of_memref
 func.func @memref_of_memref() {
   // Sizeof computation is as usual.
-  // ALIGNED-ALLOC: %[[NULL:.*]] = llvm.mlir.null
+  // ALIGNED-ALLOC: %[[NULL:.*]] = llvm.mlir.zero
   // ALIGNED-ALLOC: %[[PTR:.*]] = llvm.getelementptr
   // ALIGNED-ALLOC: %[[SIZEOF:.*]] = llvm.ptrtoint
 
@@ -592,7 +592,7 @@ module attributes { dlti.dl_spec = #dlti.dl_spec<#dlti.dl_entry<index, 32>> } {
   // ALIGNED-ALLOC-LABEL: @memref_of_memref_32
   func.func @memref_of_memref_32() {
     // Sizeof computation is as usual.
-    // ALIGNED-ALLOC: %[[NULL:.*]] = llvm.mlir.null
+    // ALIGNED-ALLOC: %[[NULL:.*]] = llvm.mlir.zero
     // ALIGNED-ALLOC: %[[PTR:.*]] = llvm.getelementptr
     // ALIGNED-ALLOC: %[[SIZEOF:.*]] = llvm.ptrtoint
 
@@ -615,7 +615,7 @@ module attributes { dlti.dl_spec = #dlti.dl_spec<#dlti.dl_entry<index, 32>> } {
 // ALIGNED-ALLOC-LABEL: @memref_of_memref_of_memref
 func.func @memref_of_memref_of_memref() {
   // Sizeof computation is as usual, also check the type.
-  // ALIGNED-ALLOC: %[[NULL:.*]] = llvm.mlir.null : !llvm.ptr
+  // ALIGNED-ALLOC: %[[NULL:.*]] = llvm.mlir.zero : !llvm.ptr
   // ALIGNED-ALLOC: %[[PTR:.*]] = llvm.getelementptr
   // ALIGNED-ALLOC: %[[SIZEOF:.*]] = llvm.ptrtoint
 
@@ -631,7 +631,7 @@ func.func @memref_of_memref_of_memref() {
 
 // ALIGNED-ALLOC-LABEL: @ranked_unranked
 func.func @ranked_unranked() {
-  // ALIGNED-ALLOC: llvm.mlir.null
+  // ALIGNED-ALLOC: llvm.mlir.zero
   // ALIGNED-ALLOC-SAME: !llvm.ptr
   // ALIGNED-ALLOC: llvm.getelementptr
   // ALIGNED-ALLOC: llvm.ptrtoint
diff --git a/mlir/test/Conversion/MemRefToLLVM/convert-static-memref-ops.mlir b/mlir/test/Conversion/MemRefToLLVM/convert-static-memref-ops.mlir
index 241a868f0ee05..35a6358d8f58b 100644
--- a/mlir/test/Conversion/MemRefToLLVM/convert-static-memref-ops.mlir
+++ b/mlir/test/Conversion/MemRefToLLVM/convert-static-memref-ops.mlir
@@ -3,7 +3,7 @@
 // CHECK-LABEL: func @zero_d_alloc()
 func.func @zero_d_alloc() -> memref<f32> {
 // CHECK: %[[one:.*]] = llvm.mlir.constant(1 : index) : i64
-// CHECK: %[[null:.*]] = llvm.mlir.null : !llvm.ptr
+// CHECK: %[[null:.*]] = llvm.mlir.zero : !llvm.ptr
 // CHECK: %[[gep:.*]] = llvm.getelementptr %[[null]][%[[one]]] : (!llvm.ptr, i64) -> !llvm.ptr, f32
 // CHECK: %[[size_bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr to i64
 // CHECK: %[[ptr:.*]] = llvm.call @malloc(%[[size_bytes]]) : (i64) -> !llvm.ptr
@@ -36,7 +36,7 @@ func.func @zero_d_dealloc(%arg0: memref<f32>) {
 func.func @aligned_1d_alloc() -> memref<42xf32> {
 // CHECK: %[[sz1:.*]] = llvm.mlir.constant(42 : index) : i64
 // CHECK: %[[st1:.*]] = llvm.mlir.constant(1 : index) : i64
-// CHECK: %[[null:.*]] = llvm.mlir.null : !llvm.ptr
+// CHECK: %[[null:.*]] = llvm.mlir.zero : !llvm.ptr
 // CHECK: %[[gep:.*]] = llvm.getelementptr %[[null]][%[[sz1]]] : (!llvm.ptr, i64) -> !llvm.ptr, f32
 // CHECK: %[[size_bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr to i64
 // CHECK: %[[alignment:.*]] = llvm.mlir.constant(8 : index) : i64
@@ -63,7 +63,7 @@ func.func @aligned_1d_alloc() -> memref<42xf32> {
 // CHECK-LABEL: func @static_alloc()
 func.func @static_alloc() -> memref<32x18xf32> {
 // CHECK: %[[num_elems:.*]] = llvm.mlir.constant(576 : index) : i64
-// CHECK: %[[null:.*]] = llvm.mlir.null : !llvm.ptr
+// CHECK: %[[null:.*]] = llvm.mlir.zero : !llvm.ptr
 // CHECK: %[[gep:.*]] = llvm.getelementptr %[[null]][%[[num_elems]]] : (!llvm.ptr, i64) -> !llvm.ptr, f32
 // CHECK: %[[size_bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr to i64
 // CHECK: llvm.call @malloc(%[[size_bytes]]) : (i64) -> !llvm.ptr
@@ -207,7 +207,7 @@ module attributes { dlti.dl_spec = #dlti.dl_spec<#dlti.dl_entry<index, 32>> } {
     %0 = memref.alloc(%c1) : memref<? x vector<2xf32>>
     // CHECK: %[[CST_S:.*]] = arith.constant 1 : index
     // CHECK: %[[CST:.*]] = builtin.unrealized_conversion_cast
-    // CHECK: llvm.mlir.null
+    // CHECK: llvm.mlir.zero
     // CHECK: llvm.getelementptr %{{.*}}[[CST]]
     // CHECK: llvm.ptrtoint %{{.*}} : !llvm.ptr to i32
     // CHECK: llvm.ptrtoint %{{.*}} : !llvm.ptr to i32
diff --git a/mlir/test/Conversion/MemRefToLLVM/memref-to-llvm.mlir b/mlir/test/Conversion/MemRefToLLVM/memref-to-llvm.mlir
index 9e44029ad93bd..ae487ef669474 100644
--- a/mlir/test/Conversion/MemRefToLLVM/memref-to-llvm.mlir
+++ b/mlir/test/Conversion/MemRefToLLVM/memref-to-llvm.mlir
@@ -464,7 +464,7 @@ func.func @memref_copy_ranked() {
   // CHECK: [[ONE:%.*]] = llvm.mlir.constant(1 : index) : i64
   // CHECK: [[EXTRACT0:%.*]] = llvm.extractvalue {{%.*}}[3, 0] : !llvm.struct<(ptr, ptr, i64, array<1 x i64>, array<1 x i64>)>
   // CHECK: [[MUL:%.*]] = llvm.mul [[ONE]], [[EXTRACT0]] : i64
-  // CHECK: [[NULL:%.*]] = llvm.mlir.null : !llvm.ptr
+  // CHECK: [[NULL:%.*]] = llvm.mlir.zero : !llvm.ptr
   // CHECK: [[GEP:%.*]] = llvm.getelementptr [[NULL]][1] : (!llvm.ptr) -> !llvm.ptr, f32
   // CHECK: [[PTRTOINT:%.*]] = llvm.ptrtoint [[GEP]] : !llvm.ptr to i64
   // CHECK: [[SIZE:%.*]] = llvm.mul [[MUL]], [[PTRTOINT]] : i64
@@ -495,7 +495,7 @@ func.func @memref_copy_contiguous(%in: memref<16x4xi32>, %offset: index) {
   // CHECK: [[MUL1:%.*]] = llvm.mul {{.*}}, [[EXTRACT0]] : i64
   // CHECK: [[EXTRACT1:%.*]] = llvm.extractvalue %[[DESC]][3, 1] : !llvm.struct<(ptr, ptr, i64, array<2 x i64>, array<2 x i64>)>
   // CHECK: [[MUL2:%.*]] = llvm.mul [[MUL1]], [[EXTRACT1]] : i64
-  // CHECK: [[NULL:%.*]] = llvm.mlir.null : !llvm.ptr
+  // CHECK: [[NULL:%.*]] = llvm.mlir.zero : !llvm.ptr
   // CHECK: [[GEP:%.*]] = llvm.getelementptr [[NULL]][1] : (!llvm.ptr) -> !llvm.ptr, i32
   // CHECK: [[PTRTOINT:%.*]] = llvm.ptrtoint [[GEP]] : !llvm.ptr to i64
   // CHECK: [[SIZE:%.*]] = llvm.mul [[MUL2]], [[PTRTOINT]] : i64
@@ -610,7 +610,7 @@ func.func @extract_strided_metadata(
 // -----
 
 // CHECK-LABEL: func @load_non_temporal(
-func.func @load_non_temporal(%arg0 : memref<32xf32, affine_map<(d0) -> (d0)>>) {  
+func.func @load_non_temporal(%arg0 : memref<32xf32, affine_map<(d0) -> (d0)>>) {
   %1 = arith.constant 7 : index
   // CHECK: llvm.load %{{.*}} {nontemporal} : !llvm.ptr -> f32
   %2 = memref.load %arg0[%1] {nontemporal = true} : memref<32xf32, affine_map<(d0) -> (d0)>>
diff --git a/mlir/test/Conversion/MemRefToLLVM/typed-pointers.mlir b/mlir/test/Conversion/MemRefToLLVM/typed-pointers.mlir
index 893c359b7b071..19d053ee7813b 100644
--- a/mlir/test/Conversion/MemRefToLLVM/typed-pointers.mlir
+++ b/mlir/test/Conversion/MemRefToLLVM/typed-pointers.mlir
@@ -100,7 +100,7 @@ func.func @mixed_alloc(%arg0: index, %arg1: index) -> memref<?x42x?xf32> {
 //  CHECK-NEXT:  %[[one:.*]] = llvm.mlir.constant(1 : index) : i64
 //  CHECK-NEXT:  %[[st0:.*]] = llvm.mul %[[N]], %[[c42]] : i64
 //  CHECK-NEXT:  %[[sz:.*]] = llvm.mul %[[st0]], %[[M]] : i64
-//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.null : !llvm.ptr<f32>
+//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.zero : !llvm.ptr<f32>
 //  CHECK-NEXT:  %[[gep:.*]] = llvm.getelementptr %[[null]][%[[sz]]] : (!llvm.ptr<f32>, i64) -> !llvm.ptr<f32>
 //  CHECK-NEXT:  %[[sz_bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr<f32> to i64
 //  CHECK-NEXT:  llvm.call @malloc(%[[sz_bytes]]) : (i64) -> !llvm.ptr<i8>
@@ -140,7 +140,7 @@ func.func @dynamic_alloc(%arg0: index, %arg1: index) -> memref<?x?xf32> {
 //   CHECK-DAG:  %[[N:.*]] = builtin.unrealized_conversion_cast %[[Narg]]
 //  CHECK-NEXT:  %[[one:.*]] = llvm.mlir.constant(1 : index) : i64
 //  CHECK-NEXT:  %[[sz:.*]] = llvm.mul %[[N]], %[[M]] : i64
-//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.null : !llvm.ptr<f32>
+//  CHECK-NEXT:  %[[null:.*]] = llvm.mlir.zero : !llvm.ptr<f32>
 //  CHECK-NEXT:  %[[gep:.*]] = llvm.getelementptr %[[null]][%[[sz]]] : (!llvm.ptr<f32>, i64) -> !llvm.ptr<f32>
 //  CHECK-NEXT:  %[[sz_bytes:.*]] = llvm.ptrtoint %[[gep]] : !llvm.ptr<f32> to i64
 //  CHECK-NEXT:  llvm.call @malloc(%[[sz_bytes]]) : (i64) -> !llvm.ptr<i8>
diff --git a/mlir/test/Dialect/GPU/ops.mlir b/mlir/test/Dialect/GPU/ops.mlir
index 0d2f52e8adbfc..c638e0b21ab6f 100644
--- a/mlir/test/Dialect/GPU/ops.mlir
+++ b/mlir/test/Dialect/GPU/ops.mlir
@@ -147,7 +147,7 @@ module attributes {gpu.container_module} {
     %cstI64 = arith.constant 8 : i64
     %c0 = arith.constant 0 : i32
     %t0 = gpu.wait async
-    %lowStream = llvm.mlir.null : !llvm.ptr
+    %lowStream = llvm.mlir.zero : !llvm.ptr
 
     // CHECK: gpu.launch_func @kernels::@kernel_1 blocks in (%{{.*}}, %{{.*}}, %{{.*}}) threads in (%{{.*}}, %{{.*}}, %{{.*}}) args(%{{.*}} : f32, %{{.*}} : memref<?xf32, 1>)
     gpu.launch_func @kernels::@kernel_1 blocks in (%cst, %cst, %cst) threads in (%cst, %cst, %cst) args(%0 : f32, %1 : memref<?xf32, 1>)
diff --git a/mlir/test/Dialect/LLVMIR/callgraph.mlir b/mlir/test/Dialect/LLVMIR/callgraph.mlir
index ca1044b8288c4..5be0bc6252624 100644
--- a/mlir/test/Dialect/LLVMIR/callgraph.mlir
+++ b/mlir/test/Dialect/LLVMIR/callgraph.mlir
@@ -67,8 +67,8 @@ module attributes {"test.name" = "Invoke call"} {
     %0 = llvm.mlir.constant(0 : i32) : i32
     %1 = llvm.mlir.constant(3 : i32) : i32
     %2 = llvm.mlir.constant("\01") : !llvm.array<1 x i8>
-    %3 = llvm.mlir.null : !llvm.ptr
-    %4 = llvm.mlir.null : !llvm.ptr
+    %3 = llvm.mlir.zero : !llvm.ptr
+    %4 = llvm.mlir.zero : !llvm.ptr
     %5 = llvm.mlir.addressof @_ZTIi : !llvm.ptr
     %6 = llvm.mlir.constant(1 : i32) : i32
     %7 = llvm.alloca %6 x i8 : (i32) -> !llvm.ptr
diff --git a/mlir/test/Dialect/LLVMIR/canonicalize.mlir b/mlir/test/Dialect/LLVMIR/canonicalize.mlir
index ed7efabb44b1a..5e26fa37b681d 100644
--- a/mlir/test/Dialect/LLVMIR/canonicalize.mlir
+++ b/mlir/test/Dialect/LLVMIR/canonicalize.mlir
@@ -19,7 +19,7 @@ llvm.func @fold_icmp_ne(%arg0 : vector<2xi32>) -> vector<2xi1> {
 // CHECK-LABEL: @fold_icmp_alloca
 llvm.func @fold_icmp_alloca() -> i1 {
   // CHECK: %[[C0:.*]] = llvm.mlir.constant(true) : i1
-  %c0 = llvm.mlir.null : !llvm.ptr
+  %c0 = llvm.mlir.zero : !llvm.ptr
   %c1 = arith.constant 1 : i64
   %0 = llvm.alloca %c1 x i32 : (i64) -> !llvm.ptr
   %1 = llvm.icmp "ne" %c0, %0 : !llvm.ptr
diff --git a/mlir/test/Dialect/LLVMIR/invalid.mlir b/mlir/test/Dialect/LLVMIR/invalid.mlir
index fc959009ff20c..3db07f45a5bab 100644
--- a/mlir/test/Dialect/LLVMIR/invalid.mlir
+++ b/mlir/test/Dialect/LLVMIR/invalid.mlir
@@ -545,9 +545,9 @@ func.func @invalid_vector_type_5(%a : vector<4xf32>, %idx : i32) -> vector<4xf32
 
 // -----
 
-func.func @null_non_llvm_type() {
-  // expected-error@+1 {{'llvm.mlir.null' op result #0 must be LLVM pointer type, but got 'i32'}}
-  llvm.mlir.null : i32
+func.func @zero_non_llvm_type() {
+  // expected-error@+1 {{'llvm.mlir.zero' op result #0 must be LLVM dialect-compatible type, but got 'tensor<4xi32>'}}
+  llvm.mlir.zero : tensor<4xi32>
 }
 
 // -----
diff --git a/mlir/test/Dialect/LLVMIR/mem2reg.mlir b/mlir/test/Dialect/LLVMIR/mem2reg.mlir
index fc696c5073c30..30ba459d07a49 100644
--- a/mlir/test/Dialect/LLVMIR/mem2reg.mlir
+++ b/mlir/test/Dialect/LLVMIR/mem2reg.mlir
@@ -16,7 +16,7 @@ llvm.func @default_value() -> i32 {
 llvm.func @store_of_ptr() {
   %0 = llvm.mlir.constant(1 : i32) : i32
   %1 = llvm.mlir.constant(4 : i32) : i32
-  %2 = llvm.mlir.null : !llvm.ptr
+  %2 = llvm.mlir.zero : !llvm.ptr
   // CHECK: %[[ALLOCA:.*]] = llvm.alloca
   %3 = llvm.alloca %0 x i32 {alignment = 4 : i64} : (i32) -> !llvm.ptr
   // CHECK: llvm.store %{{.*}}, %[[ALLOCA]]
@@ -55,7 +55,7 @@ llvm.func @unreachable_in_loop() -> i32 {
   llvm.store %1, %3 {alignment = 4 : i64} : i32, !llvm.ptr
   // CHECK: llvm.br ^[[LOOP:.*]]
   llvm.br ^bb1
-  
+
 // CHECK: ^[[LOOP]]:
 ^bb1:  // 2 preds: ^bb0, ^bb3
   // CHECK-NEXT: llvm.br ^[[ENDOFLOOP:.*]]
@@ -66,7 +66,7 @@ llvm.func @unreachable_in_loop() -> i32 {
 ^bb2:  // no predecessors
   // CHECK-NEXT: llvm.br ^[[ENDOFLOOP]]
   llvm.br ^bb3
-  
+
 // CHECK: ^[[ENDOFLOOP]]:
 ^bb3:  // 2 preds: ^bb1, ^bb2
   // CHECK-NEXT: llvm.br ^[[LOOP]]
@@ -421,8 +421,8 @@ llvm.func @ignore_discardable_tree() {
   %1 = llvm.mlir.constant(0 : i16) : i16
   %2 = llvm.mlir.constant(0 : i8) : i8
   %3 = llvm.mlir.undef : !llvm.struct<(i8, i16)>
-  %4 = llvm.insertvalue %2, %3[0] : !llvm.struct<(i8, i16)> 
-  %5 = llvm.insertvalue %1, %4[1] : !llvm.struct<(i8, i16)> 
+  %4 = llvm.insertvalue %2, %3[0] : !llvm.struct<(i8, i16)>
+  %5 = llvm.insertvalue %1, %4[1] : !llvm.struct<(i8, i16)>
   %6 = llvm.alloca %0 x !llvm.struct<(i8, i16)> {alignment = 8 : i64} : (i32) -> !llvm.ptr
   %7 = llvm.getelementptr %6[0, 0] : (!llvm.ptr) -> !llvm.ptr, !llvm.struct<(i8, i16)>
   llvm.intr.lifetime.start 2, %7 : !llvm.ptr
diff --git a/mlir/test/Dialect/LLVMIR/roundtrip-typed-pointers.mlir b/mlir/test/Dialect/LLVMIR/roundtrip-typed-pointers.mlir
index 7cc5a6deee541..b1d72b690595c 100644
--- a/mlir/test/Dialect/LLVMIR/roundtrip-typed-pointers.mlir
+++ b/mlir/test/Dialect/LLVMIR/roundtrip-typed-pointers.mlir
@@ -39,10 +39,10 @@ func.func @alloca(%size : i64) {
 
 // CHECK-LABEL: @null
 func.func @null() {
-  // CHECK: llvm.mlir.null : !llvm.ptr<i8>
-  %0 = llvm.mlir.null : !llvm.ptr<i8>
-  // CHECK: llvm.mlir.null : !llvm.ptr<struct<(ptr<func<void (i32, ptr<func<void ()>>)>>, i64)>>
-  %1 = llvm.mlir.null : !llvm.ptr<struct<(ptr<func<void (i32, ptr<func<void ()>>)>>, i64)>>
+  // CHECK: llvm.mlir.zero : !llvm.ptr<i8>
+  %0 = llvm.mlir.zero : !llvm.ptr<i8>
+  // CHECK: llvm.mlir.zero : !llvm.ptr<struct<(ptr<func<void (i32, ptr<func<void ()>>)>>, i64)>>
+  %1 = llvm.mlir.zero : !llvm.ptr<struct<(ptr<func<void (i32, ptr<func<void ()>>)>>, i64)>>
   llvm.return
 }
 
diff --git a/mlir/test/Dialect/LLVMIR/roundtrip.mlir b/mlir/test/Dialect/LLVMIR/roundtrip.mlir
index 558ed3058fe75..654048d873234 100644
--- a/mlir/test/Dialect/LLVMIR/roundtrip.mlir
+++ b/mlir/test/Dialect/LLVMIR/roundtrip.mlir
@@ -329,8 +329,8 @@ func.func @alloca(%size : i64) {
 
 // CHECK-LABEL: @null
 func.func @null() {
-  // CHECK: llvm.mlir.null : !llvm.ptr
-  %0 = llvm.mlir.null : !llvm.ptr
+  // CHECK: llvm.mlir.zero : !llvm.ptr
+  %0 = llvm.mlir.zero : !llvm.ptr
   llvm.return
 }
 
@@ -386,7 +386,7 @@ llvm.func @invokeLandingpad() -> i32 attributes { personality = @__gxx_personali
 // CHECK: %[[V0:.*]] = llvm.mlir.constant(0 : i32) : i32
 // CHECK: %{{.*}} = llvm.mlir.constant(3 : i32) : i32
 // CHECK: %[[V1:.*]] = llvm.mlir.constant("\01") : !llvm.array<1 x i8>
-// CHECK: %[[V2:.*]] = llvm.mlir.null : !llvm.ptr
+// CHECK: %[[V2:.*]] = llvm.mlir.zero : !llvm.ptr
 // CHECK: %[[V3:.*]] = llvm.mlir.addressof @_ZTIi : !llvm.ptr
 // CHECK: %[[V4:.*]] = llvm.mlir.constant(1 : i32) : i32
 // CHECK: %[[V5:.*]] = llvm.alloca %[[V4]] x i8 : (i32) -> !llvm.ptr
@@ -394,7 +394,7 @@ llvm.func @invokeLandingpad() -> i32 attributes { personality = @__gxx_personali
   %0 = llvm.mlir.constant(0 : i32) : i32
   %1 = llvm.mlir.constant(3 : i32) : i32
   %2 = llvm.mlir.constant("\01") : !llvm.array<1 x i8>
-  %3 = llvm.mlir.null : !llvm.ptr
+  %3 = llvm.mlir.zero : !llvm.ptr
   %4 = llvm.mlir.addressof @_ZTIi : !llvm.ptr
   %5 = llvm.mlir.constant(1 : i32) : i32
   %6 = llvm.alloca %5 x i8 : (i32) -> !llvm.ptr
diff --git a/mlir/test/Dialect/SparseTensor/conversion.mlir b/mlir/test/Dialect/SparseTensor/conversion.mlir
index 9cc5cc01544cc..9d337b929fa42 100644
--- a/mlir/test/Dialect/SparseTensor/conversion.mlir
+++ b/mlir/test/Dialect/SparseTensor/conversion.mlir
@@ -146,7 +146,7 @@ func.func @sparse_new3d(%arg0: !llvm.ptr<i8>) -> tensor<?x?x?xf32, #SparseTensor
 //   CHECK-DAG: %[[Iota:.*]] = memref.cast %[[Iota0]] : memref<2xindex> to memref<?xindex>
 //   CHECK-DAG: memref.store %[[I]], %[[DimSizes0]][%[[C0]]] : memref<2xindex>
 //   CHECK-DAG: memref.store %[[J]], %[[DimSizes0]][%[[C1]]] : memref<2xindex>
-//       CHECK: %[[NP:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+//       CHECK: %[[NP:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 //       CHECK: %[[T:.*]] = call @newSparseTensor(%[[DimSizes]], %[[LvlSizes]], %[[LvlTypes]], %[[Iota]], %[[Iota]], %{{.*}}, %{{.*}}, %{{.*}}, %[[Empty]], %[[NP]])
 //       CHECK: return %[[T]] : !llvm.ptr<i8>
 func.func @sparse_init(%arg0: index, %arg1: index) -> tensor<?x?xf64, #CSR> {
diff --git a/mlir/test/Dialect/SparseTensor/convert_dense2sparse.mlir b/mlir/test/Dialect/SparseTensor/convert_dense2sparse.mlir
index 9fb1946d56263..2e361e940f8e1 100644
--- a/mlir/test/Dialect/SparseTensor/convert_dense2sparse.mlir
+++ b/mlir/test/Dialect/SparseTensor/convert_dense2sparse.mlir
@@ -34,7 +34,7 @@
 //   CHECK-DAG: %[[DimSizesP:.*]] = memref.cast %[[DimSizes]] : memref<1xindex> to memref<?xindex>
 //   CHECK-DAG: %[[LvlSizesP:.*]] = memref.cast %[[LvlSizes]] : memref<1xindex> to memref<?xindex>
 //   CHECK-DAG: %[[IotaP:.*]] = memref.cast %[[Iota]] : memref<1xindex> to memref<?xindex>
-//       CHECK: %[[NP:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+//       CHECK: %[[NP:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 //       CHECK: %[[C:.*]] = call @newSparseTensor(%[[DimSizesP]], %[[LvlSizesP]], %[[LvlTypesP]], %[[IotaP]], %[[IotaP]], %{{.*}}, %{{.*}}, %{{.*}}, %[[EmptyCOO]], %[[NP]])
 //       CHECK: %[[M:.*]] = memref.alloca() : memref<1xindex>
 //       CHECK: %[[T:.*]] = memref.cast %[[M]] : memref<1xindex> to memref<?xindex>
@@ -92,7 +92,7 @@ func.func @sparse_convert_complex(%arg0: tensor<100xcomplex<f64>>) -> tensor<100
 //   CHECK-DAG: %[[DimSizesP:.*]] = memref.cast %[[DimSizes]] : memref<2xindex> to memref<?xindex>
 //   CHECK-DAG: %[[LvlSizesP:.*]] = memref.cast %[[LvlSizes]] : memref<2xindex> to memref<?xindex>
 //   CHECK-DAG: %[[IotaP:.*]] = memref.cast %[[Iota]] : memref<2xindex> to memref<?xindex>
-//       CHECK: %[[NP:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+//       CHECK: %[[NP:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 //       CHECK: %[[C:.*]] = call @newSparseTensor(%[[DimSizesP]], %[[LvlSizesP]], %[[LvlTypesP]], %[[IotaP]], %[[IotaP]], %{{.*}}, %{{.*}}, %{{.*}}, %[[EmptyCOO]], %[[NP]])
 //       CHECK: %[[M:.*]] = memref.alloca() : memref<2xindex>
 //       CHECK: %[[T:.*]] = memref.cast %[[M]] : memref<2xindex> to memref<?xindex>
@@ -146,7 +146,7 @@ func.func @sparse_convert_2d(%arg0: tensor<2x4xf64>) -> tensor<2x4xf64, #CSR> {
 //   CHECK-DAG: %[[DimSizesP:.*]] = memref.cast %[[DimSizes]] : memref<2xindex> to memref<?xindex>
 //   CHECK-DAG: %[[LvlSizesP:.*]] = memref.cast %[[LvlSizes]] : memref<2xindex> to memref<?xindex>
 //   CHECK-DAG: %[[IotaP:.*]] = memref.cast %[[Iota]] : memref<2xindex> to memref<?xindex>
-//       CHECK: %[[NP:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+//       CHECK: %[[NP:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 //       CHECK: %[[C:.*]] = call @newSparseTensor(%[[DimSizesP]], %[[LvlSizesP]], %[[LvlTypesP]], %[[IotaP]], %[[IotaP]], %{{.*}}, %{{.*}}, %{{.*}}, %[[EmptyCOO]], %[[NP]])
 //       CHECK: %[[M:.*]] = memref.alloca() : memref<2xindex>
 //       CHECK: %[[N:.*]] = memref.cast %[[M]] : memref<2xindex> to memref<?xindex>
@@ -220,7 +220,7 @@ func.func @sparse_constant_csc() -> tensor<8x7xf32, #CSC>{
 //   CHECK-DAG: %[[LvlSizesP:.*]] = memref.cast %[[LvlSizes]] : memref<3xindex> to memref<?xindex>
 //   CHECK-DAG: %[[Lvl2DimP:.*]] = memref.cast %[[Lvl2Dim]] : memref<3xindex> to memref<?xindex>
 //   CHECK-DAG: %[[Dim2LvlP:.*]] = memref.cast %[[Dim2Lvl]] : memref<3xindex> to memref<?xindex>
-//       CHECK: %[[NP:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+//       CHECK: %[[NP:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 //       CHECK: %[[C:.*]] = call @newSparseTensor(%[[DimSizesP]], %[[LvlSizesP]], %[[LvlTypesP]], %[[Lvl2DimP]], %[[Dim2LvlP]], %{{.*}}, %{{.*}}, %{{.*}}, %[[EmptyCOO]], %[[NP]])
 //       CHECK: %[[M:.*]] = memref.alloca() : memref<3xindex>
 //       CHECK: %[[N:.*]] = memref.cast %[[M]] : memref<3xindex> to memref<?xindex>
diff --git a/mlir/test/Dialect/SparseTensor/sparse_concat.mlir b/mlir/test/Dialect/SparseTensor/sparse_concat.mlir
index 5f412e59dba9f..a243157559443 100644
--- a/mlir/test/Dialect/SparseTensor/sparse_concat.mlir
+++ b/mlir/test/Dialect/SparseTensor/sparse_concat.mlir
@@ -99,7 +99,7 @@ func.func @concat_mix_dense(%arg0: tensor<2x4xf64>, %arg1: tensor<3x4xf64, #Spar
 // CHECK-DAG:     %[[IotaP_0:.*]] = memref.cast %[[Iota_0]] : memref<2xindex> to memref<?xindex>
 // CHECK-DAG:     memref.store %[[TMP_c0]], %[[Iota_0]][%[[TMP_c0]]] : memref<2xindex>
 // CHECK-DAG:     memref.store %[[TMP_c1]], %[[Iota_0]][%[[TMP_c1]]] : memref<2xindex>
-// CHECK-DAG:     %[[NullPtr:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK-DAG:     %[[NullPtr:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:         %[[TMP_7:.*]] = call @newSparseTensor(%[[DimSizesP_0]], %[[LvlSizesP_0]], %[[LvlTypesP_0]], %[[IotaP_0]], %[[IotaP_0]], %[[TMP_c0_i32]], %[[TMP_c0_i32]], %[[TMP_c1_i32]], %[[TMP_c4_i32]], %[[NullPtr]])
 // CHECK:         %[[TMP_9:.*]] = memref.alloca() : memref<2xindex>
 // CHECK:         %[[TMP_10:.*]] = memref.cast %[[TMP_9]] : memref<2xindex> to memref<?xindex>
@@ -189,7 +189,7 @@ func.func @concat_mix_sparse(%arg0: tensor<2x4xf64>, %arg1: tensor<3x4xf64, #Spa
 // CHECK-DAG:     %[[Dim2LvlP_0:.*]] = memref.cast %[[Dim2Lvl_0]] : memref<2xindex> to memref<?xindex>
 // CHECK-DAG:     memref.store %[[TMP_c1]], %[[Dim2Lvl_0]][%[[TMP_c0]]] : memref<2xindex>
 // CHECK-DAG:     memref.store %[[TMP_c0]], %[[Dim2Lvl_0]][%[[TMP_c1]]] : memref<2xindex>
-// CHECK-DAG:     %[[NullPtr:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK-DAG:     %[[NullPtr:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:         %[[TMP_7:.*]] = call @newSparseTensor(%[[DimSizesP_0]], %[[LvlSizesP_0]], %[[LvlTypesP_0]], %[[Lvl2DimP_0]], %[[Dim2LvlP_0]], %[[TMP_c0_i32]], %[[TMP_c0_i32]], %[[TMP_c1_i32]], %[[TMP_c4_i32]], %[[NullPtr]])
 // CHECK:         %[[TMP_9:.*]] = memref.alloca() : memref<2xindex>
 // CHECK:         %[[TMP_10:.*]] = memref.cast %[[TMP_9]] : memref<2xindex> to memref<?xindex>
@@ -404,7 +404,7 @@ func.func @concat_mix_dense_perm_dim1_dyn(%arg0: tensor<3x2xf64>, %arg1: tensor<
 // CHECK-DAG:     %[[Dim2LvlP_0:.*]] = memref.cast %[[Dim2Lvl_0]] : memref<2xindex> to memref<?xindex>
 // CHECK-DAG:     memref.store %[[TMP_c1]], %[[Dim2Lvl_0]][%[[TMP_c0]]] : memref<2xindex>
 // CHECK-DAG:     memref.store %[[TMP_c0]], %[[Dim2Lvl_0]][%[[TMP_c1]]] : memref<2xindex>
-// CHECK-DAG:     %[[NullPtr:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK-DAG:     %[[NullPtr:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:         %[[TMP_7:.*]] = call @newSparseTensor(%[[DimSizesP_0]], %[[LvlSizesP_0]], %[[LvlTypesP_0]], %[[Lvl2DimP_0]], %[[Dim2LvlP_0]], %[[TMP_c0_i32]], %[[TMP_c0_i32]], %[[TMP_c1_i32]], %[[TMP_c0_i32]], %[[NullPtr]])
 // CHECK:         %[[Values_r:.*]] = call @sparseValuesF64(%[[TMP_7]]) : (!llvm.ptr<i8>) -> memref<?xf64>
 // CHECK:         %[[Values:.*]] = memref.reshape %[[Values_r]]
diff --git a/mlir/test/Dialect/SparseTensor/sparse_fill_zero.mlir b/mlir/test/Dialect/SparseTensor/sparse_fill_zero.mlir
index 7a4989304b5be..e1fe5d85e72ec 100644
--- a/mlir/test/Dialect/SparseTensor/sparse_fill_zero.mlir
+++ b/mlir/test/Dialect/SparseTensor/sparse_fill_zero.mlir
@@ -31,7 +31,7 @@
 // CHECK-DAG:       %[[IotaP:.*]] = memref.cast %[[Iota]] : memref<2xindex> to memref<?xindex>
 // CHECK-DAG:       memref.store %[[I0]], %[[Iota]]{{\[}}%[[I0]]] : memref<2xindex>
 // CHECK-DAG:       memref.store %[[I1]], %[[Iota]]{{\[}}%[[I1]]] : memref<2xindex>
-// CHECK-DAG:       %[[NullPtr:.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK-DAG:       %[[NullPtr:.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK:           %[[VAL_19:.*]] = call @newSparseTensor(%[[DimSizesP]], %[[LvlSizesP]], %[[LvlTypesP]], %[[IotaP]], %[[IotaP]], %[[C0]], %[[C0]], %[[C1]], %[[C0]], %[[NullPtr]]) : (memref<?xindex>, memref<?xindex>, memref<?xi8>, memref<?xindex>, memref<?xindex>, i32, i32, i32, i32, !llvm.ptr<i8>) -> !llvm.ptr<i8>
 // CHECK:           %[[VAL_20:.*]] = memref.alloc() : memref<300xf64>
 // CHECK:           %[[VAL_21:.*]] = memref.cast %[[VAL_20]] : memref<300xf64> to memref<?xf64>
diff --git a/mlir/test/Target/LLVMIR/Import/constant.ll b/mlir/test/Target/LLVMIR/Import/constant.ll
index 85cde7b1bcfef..620c1d3772d05 100644
--- a/mlir/test/Target/LLVMIR/Import/constant.ll
+++ b/mlir/test/Target/LLVMIR/Import/constant.ll
@@ -49,7 +49,7 @@ define void @undef_constant(i32 %arg0) {
 
 ; CHECK-LABEL: @null_constant
 define ptr @null_constant() {
-  ; CHECK:  %[[NULL:[0-9]+]] = llvm.mlir.null : !llvm.ptr
+  ; CHECK:  %[[NULL:[0-9]+]] = llvm.mlir.zero : !llvm.ptr
   ; CHECK:  llvm.return %[[NULL]] : !llvm.ptr
   ret ptr null
 }
@@ -180,7 +180,7 @@ define i32 @function_address_after_def() {
 ; CHECK-DAG:  %[[CHAIN1:.+]] = llvm.insertvalue %[[C2]], %[[CHAIN0]][1]
 ; CHECK-DAG:  %[[CHAIN2:.+]] = llvm.insertvalue %[[C3]], %[[CHAIN1]][2]
 ; CHECK-DAG:  %[[CHAIN3:.+]] = llvm.insertvalue %[[C4]], %[[CHAIN2]][3]
-; CHECK-DAG:  %[[NULL:.+]] = llvm.mlir.null : !llvm.ptr
+; CHECK-DAG:  %[[NULL:.+]] = llvm.mlir.zero : !llvm.ptr
 ; CHECK-DAG:  %[[ROOT:.+]] = llvm.mlir.undef : !llvm.struct<"nested_agg_type", (struct<"simple_agg_type", (i32, i8, i16, i32)>, ptr)>
 ; CHECK-DAG:  %[[CHAIN4:.+]] = llvm.insertvalue %[[CHAIN3]], %[[ROOT]][0]
 ; CHECK-DAG:  %[[CHAIN5:.+]] = llvm.insertvalue %[[NULL]], %[[CHAIN4]][1]
@@ -188,7 +188,7 @@ define i32 @function_address_after_def() {
 %nested_agg_type = type {%simple_agg_type, ptr}
 @nested_agg = global %nested_agg_type { %simple_agg_type{i32 1, i8 2, i16 3, i32 4}, ptr null }
 
-; CHECK-DAG:  %[[NULL:.+]] = llvm.mlir.null : !llvm.ptr
+; CHECK-DAG:  %[[NULL:.+]] = llvm.mlir.zero : !llvm.ptr
 ; CHECK-DAG:  %[[ROOT:.+]] = llvm.mlir.undef : !llvm.vec<2 x ptr>
 ; CHECK-DAG:  %[[P0:.+]] = llvm.mlir.constant(0 : i32) : i32
 ; CHECK-DAG:  %[[CHAIN0:.+]] = llvm.insertelement %[[NULL]], %[[ROOT]][%[[P0]] : i32] : !llvm.vec<2 x ptr>
diff --git a/mlir/test/Target/LLVMIR/Import/exception.ll b/mlir/test/Target/LLVMIR/Import/exception.ll
index 944e5de6badd9..1bdfa6f3646e9 100644
--- a/mlir/test/Target/LLVMIR/Import/exception.ll
+++ b/mlir/test/Target/LLVMIR/Import/exception.ll
@@ -72,7 +72,7 @@ entry:
   ; CHECK: %[[c0:.*]] = llvm.mlir.constant(0 : i32) : i32
   ; CHECK: %[[c1:.*]] = llvm.mlir.constant(1 : i32) : i32
   ; CHECK: %[[c2:.*]] = llvm.mlir.constant(2 : i32) : i32
-  ; CHECK: %[[c20:.*]] = llvm.mlir.constant(20 : i32) : i32  
+  ; CHECK: %[[c20:.*]] = llvm.mlir.constant(20 : i32) : i32
   ; CHECK: llvm.cond_br %[[cond]], ^[[bb1:.*]], ^[[bb2:.*]]
   br i1 %cond, label %call, label %nocall
 ; CHECK: ^[[bb1]]:
@@ -111,7 +111,7 @@ declare void @f2({ptr, i32})
 ; CHECK-LABEL: @landingpad_dominance
 define void @landingpad_dominance() personality ptr @__gxx_personality_v0 {
 entry:
-  ; CHECK:    %[[null:.*]] = llvm.mlir.null : !llvm.ptr
+  ; CHECK:    %[[null:.*]] = llvm.mlir.zero : !llvm.ptr
   ; CHECK:    %[[c1:.*]] = llvm.mlir.constant(0 : i32) : i32
   ; CHECK:    %[[undef:.*]] = llvm.mlir.undef : !llvm.struct<(ptr, i32)>
   ; CHECK:    %[[tmpstruct:.*]] = llvm.insertvalue %[[null]], %[[undef]][0] : !llvm.struct<(ptr, i32)>
diff --git a/mlir/test/Target/LLVMIR/Import/instructions.ll b/mlir/test/Target/LLVMIR/Import/instructions.ll
index 3f5ade4f15735..b72e72c8392d9 100644
--- a/mlir/test/Target/LLVMIR/Import/instructions.ll
+++ b/mlir/test/Target/LLVMIR/Import/instructions.ll
@@ -182,7 +182,7 @@ define void @integer_extension_and_truncation(i32 %arg1) {
 ; CHECK-SAME:  %[[ARG1:[a-zA-Z0-9]+]]
 ; CHECK-SAME:  %[[ARG2:[a-zA-Z0-9]+]]
 define ptr @pointer_casts(ptr %arg1, i64 %arg2) {
-  ; CHECK:  %[[NULL:[0-9]+]] = llvm.mlir.null : !llvm.ptr
+  ; CHECK:  %[[NULL:[0-9]+]] = llvm.mlir.zero : !llvm.ptr
   ; CHECK:  llvm.ptrtoint %[[ARG1]] : !llvm.ptr to i64
   ; CHECK:  llvm.inttoptr %[[ARG2]] : i64 to !llvm.ptr
   ; CHECK:  llvm.bitcast %[[ARG1]] : !llvm.ptr to !llvm.ptr
diff --git a/mlir/test/Target/LLVMIR/Import/zeroinitializer.ll b/mlir/test/Target/LLVMIR/Import/zeroinitializer.ll
index 41933dcbe7cb1..da3eae3e9e337 100644
--- a/mlir/test/Target/LLVMIR/Import/zeroinitializer.ll
+++ b/mlir/test/Target/LLVMIR/Import/zeroinitializer.ll
@@ -4,7 +4,7 @@
 
 ; CHECK: llvm.mlir.global external @D()
 ; CHECK-SAME: !llvm.struct<"Domain", (ptr, ptr)>
-; CHECK: %[[E0:.+]] = llvm.mlir.null : !llvm.ptr
+; CHECK: %[[E0:.+]] = llvm.mlir.zero : !llvm.ptr
 ; CHECK: %[[ROOT:.+]] = llvm.mlir.undef : !llvm.struct<"Domain", (ptr, ptr)>
 ; CHECK: %[[CHAIN:.+]] = llvm.insertvalue %[[E0]], %[[ROOT]][0]
 ; CHECK: %[[RES:.+]] = llvm.insertvalue %[[E0]], %[[CHAIN]][1]
diff --git a/mlir/test/Target/LLVMIR/llvmir-intrinsics.mlir b/mlir/test/Target/LLVMIR/llvmir-intrinsics.mlir
index 6bbd761b6e613..d23991b65523f 100644
--- a/mlir/test/Target/LLVMIR/llvmir-intrinsics.mlir
+++ b/mlir/test/Target/LLVMIR/llvmir-intrinsics.mlir
@@ -640,14 +640,14 @@ llvm.func @ushl_sat_test(%arg0: i32, %arg1: i32, %arg2: vector<8xi32>, %arg3: ve
 // CHECK-LABEL: @coro_id
 llvm.func @coro_id(%arg0: i32, %arg1: !llvm.ptr) {
   // CHECK: call token @llvm.coro.id
-  %null = llvm.mlir.null : !llvm.ptr
+  %null = llvm.mlir.zero : !llvm.ptr
   llvm.intr.coro.id %arg0, %arg1, %arg1, %null : (i32, !llvm.ptr, !llvm.ptr, !llvm.ptr) -> !llvm.token
   llvm.return
 }
 
 // CHECK-LABEL: @coro_begin
 llvm.func @coro_begin(%arg0: i32, %arg1: !llvm.ptr) {
-  %null = llvm.mlir.null : !llvm.ptr
+  %null = llvm.mlir.zero : !llvm.ptr
   %token = llvm.intr.coro.id %arg0, %arg1, %arg1, %null : (i32, !llvm.ptr, !llvm.ptr, !llvm.ptr) -> !llvm.token
   // CHECK: call ptr @llvm.coro.begin
   llvm.intr.coro.begin %token, %arg1 : (!llvm.token, !llvm.ptr) -> !llvm.ptr
@@ -681,7 +681,7 @@ llvm.func @coro_save(%arg0: !llvm.ptr) {
 
 // CHECK-LABEL: @coro_suspend
 llvm.func @coro_suspend(%arg0: i32, %arg1 : i1, %arg2 : !llvm.ptr) {
-  %null = llvm.mlir.null : !llvm.ptr
+  %null = llvm.mlir.zero : !llvm.ptr
   %token = llvm.intr.coro.id %arg0, %arg2, %arg2, %null : (i32, !llvm.ptr, !llvm.ptr, !llvm.ptr) -> !llvm.token
   // CHECK: call i8 @llvm.coro.suspend
   %0 = llvm.intr.coro.suspend %token, %arg1 : i8
@@ -698,7 +698,7 @@ llvm.func @coro_end(%arg0: !llvm.ptr, %arg1 : i1) {
 
 // CHECK-LABEL: @coro_free
 llvm.func @coro_free(%arg0: i32, %arg1 : !llvm.ptr) {
-  %null = llvm.mlir.null : !llvm.ptr
+  %null = llvm.mlir.zero : !llvm.ptr
   %token = llvm.intr.coro.id %arg0, %arg1, %arg1, %null : (i32, !llvm.ptr, !llvm.ptr, !llvm.ptr) -> !llvm.token
   // CHECK: call ptr @llvm.coro.free
   %0 = llvm.intr.coro.free %token, %arg1 : (!llvm.token, !llvm.ptr) -> !llvm.ptr
diff --git a/mlir/test/Target/LLVMIR/llvmir.mlir b/mlir/test/Target/LLVMIR/llvmir.mlir
index d08f5b2776ee1..8317fae7dd710 100644
--- a/mlir/test/Target/LLVMIR/llvmir.mlir
+++ b/mlir/test/Target/LLVMIR/llvmir.mlir
@@ -1438,7 +1438,7 @@ llvm.func @integer_extension_and_truncation(%a : i32) {
 // Check that the auxiliary `null` operation is converted into a `null` value.
 // CHECK-LABEL: @null
 llvm.func @null() -> !llvm.ptr<i32> {
-  %0 = llvm.mlir.null : !llvm.ptr<i32>
+  %0 = llvm.mlir.zero : !llvm.ptr<i32>
   // CHECK: ret ptr null
   llvm.return %0 : !llvm.ptr<i32>
 }
@@ -1536,7 +1536,7 @@ llvm.func @invokeLandingpad() -> i32 attributes { personality = @__gxx_personali
   %1 = llvm.mlir.constant(dense<0> : vector<1xi8>) : !llvm.array<1 x i8>
   %2 = llvm.mlir.addressof @_ZTIi : !llvm.ptr<ptr<i8>>
   %3 = llvm.bitcast %2 : !llvm.ptr<ptr<i8>> to !llvm.ptr<i8>
-  %4 = llvm.mlir.null : !llvm.ptr<ptr<i8>>
+  %4 = llvm.mlir.zero : !llvm.ptr<ptr<i8>>
   %5 = llvm.mlir.constant(1 : i32) : i32
   %6 = llvm.alloca %5 x i8 : (i32) -> !llvm.ptr<i8>
 // CHECK: invoke void @foo(ptr %[[a1]])
diff --git a/mlir/test/Target/LLVMIR/omptarget-declare-target-llvm-host.mlir b/mlir/test/Target/LLVMIR/omptarget-declare-target-llvm-host.mlir
index 709af26f1d3df..82aff6f131ef1 100644
--- a/mlir/test/Target/LLVMIR/omptarget-declare-target-llvm-host.mlir
+++ b/mlir/test/Target/LLVMIR/omptarget-declare-target-llvm-host.mlir
@@ -1,31 +1,31 @@
 // RUN: mlir-translate -mlir-to-llvmir %s | FileCheck %s
 
-// CHECK-DAG: %struct.__tgt_offload_entry = type { ptr, ptr, i64, i32, i32 } 
+// CHECK-DAG: %struct.__tgt_offload_entry = type { ptr, ptr, i64, i32, i32 }
 // CHECK-DAG: !omp_offload.info = !{!{{.*}}}
 module attributes {llvm.target_triple = "x86_64-unknown-linux-gnu", omp.is_target_device = false} {
 
   // CHECK-DAG: @_QMtest_0Earray_1d = global [3 x i32] [i32 1, i32 2, i32 3]
-  // CHECK-DAG: @_QMtest_0Earray_1d_decl_tgt_ref_ptr = weak global ptr @_QMtest_0Earray_1d 
+  // CHECK-DAG: @_QMtest_0Earray_1d_decl_tgt_ref_ptr = weak global ptr @_QMtest_0Earray_1d
   // CHECK-DAG: @.omp_offloading.entry_name{{.*}} = internal unnamed_addr constant [36 x i8] c"_QMtest_0Earray_1d_decl_tgt_ref_ptr\00"
   // CHECK-DAG: @.omp_offloading.entry._QMtest_0Earray_1d_decl_tgt_ref_ptr = weak constant %struct.__tgt_offload_entry { ptr @_QMtest_0Earray_1d_decl_tgt_ref_ptr, ptr @.omp_offloading.entry_name{{.*}}, i64 8, i32 1, i32 0 }, section "omp_offloading_entries", align 1
   // CHECK-DAG: !{{.*}} = !{i32 {{.*}}, !"_QMtest_0Earray_1d_decl_tgt_ref_ptr", i32 {{.*}}, i32 {{.*}}}
   llvm.mlir.global external @_QMtest_0Earray_1d(dense<[1, 2, 3]> : tensor<3xi32>) {addr_space = 0 : i32, omp.declare_target = #omp.declaretarget<device_type = (any), capture_clause = (link)>} : !llvm.array<3 x i32>
 
   // CHECK-DAG: @_QMtest_0Earray_2d = global [2 x [2 x i32]] {{.*}}
-  // CHECK-DAG: @_QMtest_0Earray_2d_decl_tgt_ref_ptr = weak global ptr @_QMtest_0Earray_2d 
+  // CHECK-DAG: @_QMtest_0Earray_2d_decl_tgt_ref_ptr = weak global ptr @_QMtest_0Earray_2d
   // CHECK-DAG: @.omp_offloading.entry_name{{.*}} = internal unnamed_addr constant [36 x i8] c"_QMtest_0Earray_2d_decl_tgt_ref_ptr\00"
   // CHECK-DAG: @.omp_offloading.entry._QMtest_0Earray_2d_decl_tgt_ref_ptr = weak constant %struct.__tgt_offload_entry { ptr @_QMtest_0Earray_2d_decl_tgt_ref_ptr, ptr @.omp_offloading.entry_name{{.*}}, i64 8, i32 1, i32 0 }, section "omp_offloading_entries", align 1
   // CHECK-DAG: !{{.*}} = !{i32 {{.*}}, !"_QMtest_0Earray_2d_decl_tgt_ref_ptr", i32 {{.*}}, i32 {{.*}}}
   llvm.mlir.global external @_QMtest_0Earray_2d() {addr_space = 0 : i32, omp.declare_target = #omp.declaretarget<device_type = (any), capture_clause = (link)>} : !llvm.array<2 x array<2 x i32>> {
     %0 = llvm.mlir.undef : !llvm.array<2 x array<2 x i32>>
     %1 = llvm.mlir.constant(1 : i32) : i32
-    %2 = llvm.insertvalue %1, %0[0, 0] : !llvm.array<2 x array<2 x i32>> 
+    %2 = llvm.insertvalue %1, %0[0, 0] : !llvm.array<2 x array<2 x i32>>
     %3 = llvm.mlir.constant(2 : i32) : i32
-    %4 = llvm.insertvalue %3, %2[0, 1] : !llvm.array<2 x array<2 x i32>> 
+    %4 = llvm.insertvalue %3, %2[0, 1] : !llvm.array<2 x array<2 x i32>>
     %5 = llvm.mlir.constant(3 : i32) : i32
-    %6 = llvm.insertvalue %5, %4[1, 0] : !llvm.array<2 x array<2 x i32>> 
+    %6 = llvm.insertvalue %5, %4[1, 0] : !llvm.array<2 x array<2 x i32>>
     %7 = llvm.mlir.constant(4 : i32) : i32
-    %8 = llvm.insertvalue %7, %6[1, 1] : !llvm.array<2 x array<2 x i32>> 
+    %8 = llvm.insertvalue %7, %6[1, 1] : !llvm.array<2 x array<2 x i32>>
     %9 = llvm.mlir.constant(2 : index) : i64
     %10 = llvm.mlir.constant(2 : index) : i64
     llvm.return %8 : !llvm.array<2 x array<2 x i32>>
@@ -70,7 +70,7 @@ module attributes {llvm.target_triple = "x86_64-unknown-linux-gnu", omp.is_targe
   }
 
   // CHECK-DAG: @_QMtest_0Edata_int = global i32 1
-  // CHECK-DAG: @_QMtest_0Edata_int_decl_tgt_ref_ptr = weak global ptr @_QMtest_0Edata_int 
+  // CHECK-DAG: @_QMtest_0Edata_int_decl_tgt_ref_ptr = weak global ptr @_QMtest_0Edata_int
   // CHECK-DAG: @.omp_offloading.entry_name{{.*}} = internal unnamed_addr constant [36 x i8] c"_QMtest_0Edata_int_decl_tgt_ref_ptr\00"
   // CHECK-DAG: @.omp_offloading.entry._QMtest_0Edata_int_decl_tgt_ref_ptr = weak constant %struct.__tgt_offload_entry { ptr @_QMtest_0Edata_int_decl_tgt_ref_ptr, ptr @.omp_offloading.entry_name{{.*}}, i64 8, i32 1, i32 0 }, section "omp_offloading_entries", align 1
   // CHECK-DAG: !{{.*}} = !{i32 {{.*}}, !"_QMtest_0Edata_int_decl_tgt_ref_ptr", i32 {{.*}}, i32 {{.*}}}
@@ -103,28 +103,28 @@ module attributes {llvm.target_triple = "x86_64-unknown-linux-gnu", omp.is_targe
   // CHECK-DAG: @.omp_offloading.entry._QMtest_0Ept1_decl_tgt_ref_ptr = weak constant %struct.__tgt_offload_entry { ptr @_QMtest_0Ept1_decl_tgt_ref_ptr, ptr @.omp_offloading.entry_name{{.*}}, i64 8, i32 1, i32 0 }, section "omp_offloading_entries", align 1
   // CHECK-DAG: !{{.*}} = !{i32 {{.*}}, !"_QMtest_0Ept1_decl_tgt_ref_ptr", i32 {{.*}}, i32 {{.*}}}
   llvm.mlir.global external @_QMtest_0Ept1() {addr_space = 0 : i32, omp.declare_target = #omp.declaretarget<device_type = (any), capture_clause = (link)>} : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> {
-    %0 = llvm.mlir.null : !llvm.ptr<i32>
+    %0 = llvm.mlir.zero : !llvm.ptr<i32>
     %1 = llvm.mlir.constant(9 : i32) : i32
-    %2 = llvm.mlir.null : !llvm.ptr<i32>
+    %2 = llvm.mlir.zero : !llvm.ptr<i32>
     %3 = llvm.getelementptr %2[1] : (!llvm.ptr<i32>) -> !llvm.ptr<i32>
     %4 = llvm.ptrtoint %3 : !llvm.ptr<i32> to i64
     %5 = llvm.mlir.undef : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
-    %6 = llvm.insertvalue %4, %5[1] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> 
+    %6 = llvm.insertvalue %4, %5[1] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
     %7 = llvm.mlir.constant(20180515 : i32) : i32
-    %8 = llvm.insertvalue %7, %6[2] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> 
+    %8 = llvm.insertvalue %7, %6[2] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
     %9 = llvm.mlir.constant(0 : i32) : i32
     %10 = llvm.trunc %9 : i32 to i8
-    %11 = llvm.insertvalue %10, %8[3] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> 
+    %11 = llvm.insertvalue %10, %8[3] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
     %12 = llvm.trunc %1 : i32 to i8
-    %13 = llvm.insertvalue %12, %11[4] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> 
+    %13 = llvm.insertvalue %12, %11[4] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
     %14 = llvm.mlir.constant(1 : i32) : i32
     %15 = llvm.trunc %14 : i32 to i8
-    %16 = llvm.insertvalue %15, %13[5] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> 
+    %16 = llvm.insertvalue %15, %13[5] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
     %17 = llvm.mlir.constant(0 : i32) : i32
     %18 = llvm.trunc %17 : i32 to i8
-    %19 = llvm.insertvalue %18, %16[6] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> 
+    %19 = llvm.insertvalue %18, %16[6] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
     %20 = llvm.bitcast %0 : !llvm.ptr<i32> to !llvm.ptr<i32>
-    %21 = llvm.insertvalue %20, %19[0] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)> 
+    %21 = llvm.insertvalue %20, %19[0] : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
     llvm.return %21 : !llvm.struct<(ptr<i32>, i64, i32, i8, i8, i8, i8)>
   }
 
diff --git a/mlir/test/Transforms/test-convert-call-op.mlir b/mlir/test/Transforms/test-convert-call-op.mlir
index f8da5f91d3c8f..dd7924edc88b8 100644
--- a/mlir/test/Transforms/test-convert-call-op.mlir
+++ b/mlir/test/Transforms/test-convert-call-op.mlir
@@ -9,6 +9,6 @@ func.func @caller() -> i32 {
   %out = call @callee(%arg) : (!test.test_type) -> i32
   return %out : i32
 }
-// CHECK-NEXT: [[ARG:%.*]] = llvm.mlir.null : !llvm.ptr<i8>
+// CHECK-NEXT: [[ARG:%.*]] = llvm.mlir.zero : !llvm.ptr<i8>
 // CHECK-NEXT: [[OUT:%.*]] = llvm.call @callee([[ARG]])
 // CHECK-SAME:     : (!llvm.ptr<i8>) -> i32
diff --git a/mlir/test/lib/Conversion/FuncToLLVM/TestConvertCallOp.cpp b/mlir/test/lib/Conversion/FuncToLLVM/TestConvertCallOp.cpp
index c741a656d13f7..9b3a1534a598e 100644
--- a/mlir/test/lib/Conversion/FuncToLLVM/TestConvertCallOp.cpp
+++ b/mlir/test/lib/Conversion/FuncToLLVM/TestConvertCallOp.cpp
@@ -27,7 +27,7 @@ class TestTypeProducerOpConverter
   LogicalResult
   matchAndRewrite(test::TestTypeProducerOp op, OpAdaptor adaptor,
                   ConversionPatternRewriter &rewriter) const override {
-    rewriter.replaceOpWithNewOp<LLVM::NullOp>(op, getVoidPtrType());
+    rewriter.replaceOpWithNewOp<LLVM::ZeroOp>(op, getVoidPtrType());
     return success();
   }
 };