_ __has_attribute Abs Assert AssertArg AssertMacro AssertPointerAlignment AssertState AssertVariableIsOfType AssertVariableIsOfTypeMacro bits16 bits32 bits8 BoolIsValid BpChar BUFFERALIGN BUFFERALIGN_DOWN bytea CACHELINEALIGN CommandId CppAsString CppAsString2 CppConcat dgettext dngettext DOUBLEALIGN DOUBLEALIGN_DOWN dummyret ESCAPE_STRING_SYNTAX ExceptionalCondition FirstCommandId FLEXIBLE_ARRAY_MEMBER float4 FLOAT4_FITS_IN_INT16 FLOAT4_FITS_IN_INT32 FLOAT4_FITS_IN_INT64 float8 FLOAT8_FITS_IN_INT16 FLOAT8_FITS_IN_INT32 FLOAT8_FITS_IN_INT64 FLOAT8PASSBYVAL gettext gettext_noop HAVE_INT64_TIMESTAMP HAVE_UNIX_SOCKETS HIGHBIT Index int16 int32 int64 INT64_FORMAT INT64CONST int8 INTALIGN INTALIGN_DOWN InvalidCommandId InvalidSubTransactionId INVERT_COMPARE_RESULT IS_HIGHBIT_SET lengthof likely LocalTransactionId LONG_ALIGN_MASK LONGALIGN LONGALIGN_DOWN Max MAXALIGN MAXALIGN64 MAXALIGN_DOWN MemSet MemSetAligned MemSetLoop MemSetTest Min MultiXactId MultiXactOffset ngettext NON_EXEC_STATIC Offset offsetof OffsetToPointer OidIsValid pg_attribute_always_inline pg_attribute_cold pg_attribute_format_arg pg_attribute_hot pg_attribute_no_sanitize_alignment pg_attribute_noreturn pg_attribute_printf pg_attribute_unused PG_BINARY PG_BINARY_A PG_BINARY_R PG_BINARY_W PG_FUNCNAME_MACRO pg_funcptr_t PG_INT16_MAX PG_INT16_MIN PG_INT32_MAX PG_INT32_MIN PG_INT64_MAX PG_INT64_MIN PG_INT8_MAX PG_INT8_MIN pg_nodiscard pg_noinline PG_TEXTDOMAIN PG_UINT16_MAX PG_UINT32_MAX PG_UINT64_MAX PG_UINT8_MAX pg_unreachable PG_USED_FOR_ASSERTS_ONLY PGAlignedBlock PGAlignedXLogBlock PGDLLIMPORT Pointer PointerIsAligned PointerIsValid regproc RegProcedure RegProcedureIsValid SHORTALIGN SHORTALIGN_DOWN SIGNAL_ARGS Size SQL_STR_DOUBLE StaticAssertDecl StaticAssertExpr StaticAssertStmt STATUS_EOF STATUS_ERROR STATUS_OK SubTransactionId text TopSubTransactionId TransactionId Trap TrapMacro TYPEALIGN TYPEALIGN64 TYPEALIGN_DOWN uint16 uint32 uint64 UINT64_FORMAT UINT64CONST uint8 unconstify unlikely unvolatize VA_ARGS_NARGS VA_ARGS_NARGS_ VarChar VARHDRSZ

MemSetTest #define MemSetTest (   val,   len  ) Value: ( ((len) & LONG_ALIGN_MASK) == 0 && \ (len) <= MEMSET_LOOP_LIMIT && \ MEMSET_LOOP_LIMIT != 0 && \ (val) == 0 )