diff --git a/clang/include/clang/Basic/BuiltinsWebAssembly.def b/clang/include/clang/Basic/BuiltinsWebAssembly.def
--- a/clang/include/clang/Basic/BuiltinsWebAssembly.def
+++ b/clang/include/clang/Basic/BuiltinsWebAssembly.def
@@ -25,6 +25,10 @@
 BUILTIN(__builtin_wasm_memory_size, "zIi", "n")
 BUILTIN(__builtin_wasm_memory_grow, "zIiz", "n")
 
+// Bulk memory builtins
+TARGET_BUILTIN(__builtin_wasm_memory_init, "vIiv*ii", "", "bulk-memory")
+TARGET_BUILTIN(__builtin_wasm_data_drop, "vIi", "", "bulk-memory")
+
 // Floating point min/max
 BUILTIN(__builtin_wasm_min_f32, "fff", "nc")
 BUILTIN(__builtin_wasm_max_f32, "fff", "nc")
diff --git a/clang/lib/CodeGen/CGBuiltin.cpp b/clang/lib/CodeGen/CGBuiltin.cpp
--- a/clang/lib/CodeGen/CGBuiltin.cpp
+++ b/clang/lib/CodeGen/CGBuiltin.cpp
@@ -13470,6 +13470,34 @@
     Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_memory_grow, ResultType);
     return Builder.CreateCall(Callee, Args);
   }
+  case WebAssembly::BI__builtin_wasm_memory_init: {
+    const Expr *SegArg = E->getArg(0);
+    llvm::APSInt SegConst;
+    if (!SegArg->isIntegerConstantExpr(SegConst, getContext()))
+      llvm_unreachable("Constant arg isn't actually constant?");
+    llvm::Type *SegType = ConvertType(SegArg->getType());
+    llvm::Type *IdxType = llvm::Type::getInt32Ty(getLLVMContext());
+    llvm::Type *DstType =
+        ConvertType(E->getArg(1)->getType())->getPointerElementType();
+    Value *Args[] = {llvm::ConstantInt::get(getLLVMContext(), SegConst),
+                     llvm::ConstantInt::get(getLLVMContext(),
+                                            llvm::APSInt(llvm::APInt(32, 0))),
+                     EmitScalarExpr(E->getArg(1)), EmitScalarExpr(E->getArg(2)),
+                     EmitScalarExpr(E->getArg(3))};
+    Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_memory_init,
+                                        {SegType, IdxType, DstType});
+    return Builder.CreateCall(Callee, Args);
+  }
+  case WebAssembly::BI__builtin_wasm_data_drop: {
+    const Expr *SegArg = E->getArg(0);
+    llvm::APSInt SegConst;
+    if (!SegArg->isIntegerConstantExpr(SegConst, getContext()))
+      llvm_unreachable("Constant arg isn't actually constant?");
+    llvm::Type *SegType = ConvertType(SegArg->getType());
+    Value *Arg = llvm::ConstantInt::get(getLLVMContext(), SegConst);
+    Function *Callee = CGM.getIntrinsic(Intrinsic::wasm_data_drop, SegType);
+    return Builder.CreateCall(Callee, {Arg});
+  }
   case WebAssembly::BI__builtin_wasm_throw: {
     Value *Tag = EmitScalarExpr(E->getArg(0));
     Value *Obj = EmitScalarExpr(E->getArg(1));
diff --git a/clang/test/CodeGen/builtins-wasm.c b/clang/test/CodeGen/builtins-wasm.c
--- a/clang/test/CodeGen/builtins-wasm.c
+++ b/clang/test/CodeGen/builtins-wasm.c
@@ -1,6 +1,6 @@
-// RUN: %clang_cc1 -triple wasm32-unknown-unknown -target-feature +unimplemented-simd128 -target-feature +nontrapping-fptoint -target-feature +exception-handling -fno-lax-vector-conversions -O3 -emit-llvm -o - %s | FileCheck %s -check-prefixes WEBASSEMBLY,WEBASSEMBLY32
-// RUN: %clang_cc1 -triple wasm64-unknown-unknown -target-feature +unimplemented-simd128 -target-feature +nontrapping-fptoint -target-feature +exception-handling -fno-lax-vector-conversions -O3 -emit-llvm -o - %s | FileCheck %s -check-prefixes WEBASSEMBLY,WEBASSEMBLY64
-// RUN: not %clang_cc1 -triple wasm64-unknown-unknown -target-feature +nontrapping-fptoint -target-feature +exception-handling -fno-lax-vector-conversions -O3 -emit-llvm -o - %s 2>&1 | FileCheck %s -check-prefixes MISSING-SIMD
+// RUN: %clang_cc1 -triple wasm32-unknown-unknown -target-feature +unimplemented-simd128 -target-feature +nontrapping-fptoint -target-feature +exception-handling -target-feature +bulk-memory -fno-lax-vector-conversions -O3 -emit-llvm -o - %s | FileCheck %s -check-prefixes WEBASSEMBLY,WEBASSEMBLY32
+// RUN: %clang_cc1 -triple wasm64-unknown-unknown -target-feature +unimplemented-simd128 -target-feature +nontrapping-fptoint -target-feature +exception-handling -target-feature +bulk-memory -fno-lax-vector-conversions -O3 -emit-llvm -o - %s | FileCheck %s -check-prefixes WEBASSEMBLY,WEBASSEMBLY64
+// RUN: not %clang_cc1 -triple wasm64-unknown-unknown -target-feature +nontrapping-fptoint -target-feature +exception-handling -target-feature +bulk-memory -fno-lax-vector-conversions -O3 -emit-llvm -o - %s 2>&1 | FileCheck %s -check-prefixes MISSING-SIMD
 
 // SIMD convenience types
 typedef char i8x16 __attribute((vector_size(16)));
@@ -26,6 +26,18 @@
   // WEBASSEMBLY64: call i64 @llvm.wasm.memory.grow.i64(i32 0, i64 %{{.*}})
 }
 
+void memory_init(void *dest, int offset, int size) {
+  __builtin_wasm_memory_init(3, dest, offset, size);
+  // WEBASSEMBLY32: call void @llvm.wasm.memory.init.i32.i32.i8(i32 3, i32 0, i8* %{{.*}}, i32 %{{.*}}, i32 %{{.*}})
+  // WEBASSEMBLY64: call void @llvm.wasm.memory.init.i32.i32.i8(i32 3, i32 0, i8* %{{.*}}, i32 %{{.*}}, i32 %{{.*}})
+}
+
+void data_drop() {
+  __builtin_wasm_data_drop(3);
+  // WEBASSEMBLY32: call void @llvm.wasm.data.drop.i32(i32 3)
+  // WEBASSEMBLY64: call void @llvm.wasm.data.drop.i32(i32 3)
+}
+
 void throw(unsigned int tag, void *obj) {
   return __builtin_wasm_throw(tag, obj);
   // WEBASSEMBLY32: call void @llvm.wasm.throw(i32 %{{.*}}, i8* %{{.*}})
diff --git a/llvm/include/llvm/IR/IntrinsicsWebAssembly.td b/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
--- a/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
+++ b/llvm/include/llvm/IR/IntrinsicsWebAssembly.td
@@ -110,4 +110,20 @@
             [llvm_anyvector_ty],
             [IntrNoMem, IntrSpeculatable]>;
 
+//===----------------------------------------------------------------------===//
+// Bulk memory intrinsics
+//===----------------------------------------------------------------------===//
+
+def int_wasm_memory_init :
+  Intrinsic<[],
+            [llvm_anyint_ty, llvm_anyint_ty, LLVMPointerType<llvm_any_ty>,
+             llvm_i32_ty, llvm_i32_ty],
+            [IntrWriteMem, IntrArgMemOnly, WriteOnly<1>],
+            "", [SDNPMemOperand]>;
+def int_wasm_data_drop :
+  Intrinsic<[],
+            [llvm_anyint_ty],
+            [IntrNoDuplicate, IntrHasSideEffects],
+            "", [SDNPMemOperand]>;
+
 } // TargetPrefix = "wasm"
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrBulkMemory.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrBulkMemory.td
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrBulkMemory.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrBulkMemory.td
@@ -27,6 +27,31 @@
 def wasm_memcpy : SDNode<"WebAssemblyISD::MEMORY_COPY", wasm_memcpy_t,
                          [SDNPHasChain, SDNPMayLoad, SDNPMayStore]>;
 
+//===----------------------------------------------------------------------===//
+// memory.init
+//===----------------------------------------------------------------------===//
+
+let mayStore = 1 in
+defm MEMORY_INIT :
+  BULK_I<(outs),
+         (ins i32imm_op:$seg, i32imm_op:$idx, I32:$dest,
+              I32:$offset, I32:$size),
+         (outs), (ins i32imm_op:$seg, i32imm_op:$idx),
+         [(int_wasm_memory_init (i32 imm:$seg), (i32 imm:$idx), I32:$dest,
+            I32:$offset, I32:$size
+          )],
+         "memory.init\t$seg, $idx, $dest, $offset, $size",
+         "memory.init\t$seg, $idx", 0x08>;
+
+//===----------------------------------------------------------------------===//
+// data.drop
+//===----------------------------------------------------------------------===//
+
+defm DATA_DROP :
+  BULK_I<(outs), (ins i32imm_op:$seg), (outs), (ins i32imm_op:$seg),
+         [(int_wasm_data_drop (i32 imm:$seg))],
+         "data.drop\t$seg", "data.drop\t$seg", 0x09>;
+
 //===----------------------------------------------------------------------===//
 // memory.copy
 //===----------------------------------------------------------------------===//
diff --git a/llvm/test/CodeGen/WebAssembly/bulk-memory-intrinsics.ll b/llvm/test/CodeGen/WebAssembly/bulk-memory-intrinsics.ll
new file mode 100644
--- /dev/null
+++ b/llvm/test/CodeGen/WebAssembly/bulk-memory-intrinsics.ll
@@ -0,0 +1,28 @@
+; RUN: llc < %s -asm-verbose=false -verify-machineinstrs -disable-wasm-fallthrough-return-opt -wasm-disable-explicit-locals -wasm-keep-registers -mattr=+bulk-memory | FileCheck %s
+
+; Test that bulk memory intrinsics lower correctly
+
+target datalayout = "e-m:e-p:32:32-i64:64-n32:64-S128"
+target triple = "wasm32-unknown-unknown"
+
+; CHECK-LABEL: memory_init:
+; CHECK-NEXT: .functype  memory_init (i32, i32, i32) -> ()
+; CHECK-NEXT: memory.init 0, 3, $0, $1, $2
+; CHECK-NEXT: return
+declare void @llvm.wasm.memory.init.i32.i32.i8(i32, i32, i8*, i32, i32)
+define void @memory_init(i8* %dest, i32 %offset, i32 %size) {
+  call void @llvm.wasm.memory.init.i32.i32.i8(
+    i32 0, i32 3, i8* %dest, i32 %offset, i32 %size
+  )
+  ret void
+}
+
+; CHECK-LABEL: data_drop:
+; CHECK-NEXT: .functype  data_drop () -> ()
+; CHECK-NEXT: data.drop 3
+; CHECK-NEXT: return
+declare void @llvm.wasm.data.drop.i32(i32)
+define void @data_drop() {
+  call void @llvm.wasm.data.drop.i32(i32 3)
+  ret void
+}