[WebAssembly] Add a memory_size intrinsic.

llvm-svn: 249171
diff --git a/llvm/lib/Target/WebAssembly/WebAssemblyInstrMemory.td b/llvm/lib/Target/WebAssembly/WebAssemblyInstrMemory.td
index 84b8847..410fd47 100644
--- a/llvm/lib/Target/WebAssembly/WebAssemblyInstrMemory.td
+++ b/llvm/lib/Target/WebAssembly/WebAssemblyInstrMemory.td
@@ -98,3 +98,11 @@
 def page_size_I64 : I<(outs I64:$dst), (ins),
                       [(set I64:$dst, (int_wasm_page_size))]>,
                     Requires<[HasAddr64]>;
+
+// Memory size.
+def memory_size_I32 : I<(outs I32:$dst), (ins),
+                        [(set I32:$dst, (int_wasm_memory_size))]>,
+                      Requires<[HasAddr32]>;
+def memory_size_I64 : I<(outs I64:$dst), (ins),
+                        [(set I64:$dst, (int_wasm_memory_size))]>,
+                      Requires<[HasAddr64]>;