| // Copyright 2022 The Fuchsia Authors. All rights reserved. |
| // Use of this source code is governed by a BSD-style license that can be |
| // found in the LICENSE file. |
| |
| #ifndef ZIRCON_KERNEL_LIB_ARCH_INCLUDE_LIB_ARCH_HWREG_H_ |
| #define ZIRCON_KERNEL_LIB_ARCH_INCLUDE_LIB_ARCH_HWREG_H_ |
| |
| #include <hwreg/bitfields.h> |
| |
| namespace arch { |
| |
| // Various hwreg types declared in <lib/arch/...> headers use the template |
| // argument arch::EnablePrinter in place of hwreg::EnablePrinter. The hwreg |
| // printing support has an unreasonable runtime cost for the non-printing uses. |
| // In particular, it makes the hwreg objects very large and need runtime |
| // construction, as oppoosed to being tiny one-word objects whose construction |
| // is inlined away. This adds setup overhead to code using the types, but more |
| // importantly makes functions using several such objects get unreasonable |
| // stack sizes very quickly. So it's conditionally compiled in only in places |
| // that want that support, which is generally only useful in build-time and |
| // test code and isn't used in production code where keeping the hwreg types |
| // optimal is important. Hence, this should not be enabled when compiling code |
| // for the kernel or any such place, but only in test-only code. |
| |
| #ifdef LIB_ARCH_PRINTERS |
| using EnablePrinter = hwreg::EnablePrinter; |
| #else |
| using EnablePrinter = void; |
| #endif |
| |
| } // namespace arch |
| |
| #endif // ZIRCON_KERNEL_LIB_ARCH_INCLUDE_LIB_ARCH_HWREG_H_ |
