I'd like to use CONSTEXPR to get static initialisation of some
aarch64-specific variables. This obviously means that cross toolchains
built with old compilers won't benefit, but I hope toolchains built with
newer compilers are faster for other reasons too. :-)
The variables in question have scalar_int_mode fields, so I first
needed to make the machine_mode stuff more constexpr-friendly.
This patch therefore adds CONSTEXPR to constructors and operators in
machmode.h, excluding the controversial constexpr-resistant "() {}"
constructors, which would become "= default" if we required C++11.
Some of the other routines could potentially be constexpr too,
but that can be done on an as-needed basis.
Tested on aarch64-linux-gnu, with and without the follow-on changes.
OK to install?
Richard
2019-10-04 Richard Sandiford <richard.sandif...@arm.com>
gcc/
* machmode.h (opt_mode): Mark constructors with CONSTEXPR.
(pod_mode): Mark operators likewise.
(scalar_int_mode): Mark non-default constructors and
operators with CONSTEXPR.
(scalar_float_mode, scalar_mode, complex_mode): Likewise.
(fixed_size_mode): Likewise.
Index: gcc/machmode.h
===================================================================
--- gcc/machmode.h 2019-08-13 11:39:54.753376024 +0100
+++ gcc/machmode.h 2019-10-04 15:59:12.166948822 +0100
@@ -244,11 +244,11 @@ #define CLASS_HAS_WIDER_MODES_P(CLASS)
public:
enum from_int { dummy = MAX_MACHINE_MODE };
- ALWAYS_INLINE opt_mode () : m_mode (E_VOIDmode) {}
- ALWAYS_INLINE opt_mode (const T &m) : m_mode (m) {}
+ ALWAYS_INLINE CONSTEXPR opt_mode () : m_mode (E_VOIDmode) {}
+ ALWAYS_INLINE CONSTEXPR opt_mode (const T &m) : m_mode (m) {}
template<typename U>
- ALWAYS_INLINE opt_mode (const U &m) : m_mode (T (m)) {}
- ALWAYS_INLINE opt_mode (from_int m) : m_mode (machine_mode (m)) {}
+ ALWAYS_INLINE CONSTEXPR opt_mode (const U &m) : m_mode (T (m)) {}
+ ALWAYS_INLINE CONSTEXPR opt_mode (from_int m) : m_mode (machine_mode (m)) {}
machine_mode else_void () const;
machine_mode else_blk () const { return else_mode (BLKmode); }
@@ -324,8 +324,12 @@ struct pod_mode
typedef typename T::measurement_type measurement_type;
machine_mode m_mode;
- ALWAYS_INLINE operator machine_mode () const { return m_mode; }
- ALWAYS_INLINE operator T () const { return from_int (m_mode); }
+ ALWAYS_INLINE CONSTEXPR
+ operator machine_mode () const { return m_mode; }
+
+ ALWAYS_INLINE CONSTEXPR
+ operator T () const { return from_int (m_mode); }
+
ALWAYS_INLINE pod_mode &operator = (const T &m) { m_mode = m; return *this; }
};
@@ -403,8 +407,11 @@ is_a (machine_mode m, U *result)
typedef unsigned short measurement_type;
ALWAYS_INLINE scalar_int_mode () {}
- ALWAYS_INLINE scalar_int_mode (from_int m) : m_mode (machine_mode (m)) {}
- ALWAYS_INLINE operator machine_mode () const { return m_mode; }
+
+ ALWAYS_INLINE CONSTEXPR
+ scalar_int_mode (from_int m) : m_mode (machine_mode (m)) {}
+
+ ALWAYS_INLINE CONSTEXPR operator machine_mode () const { return m_mode; }
static bool includes_p (machine_mode);
@@ -428,8 +435,11 @@ scalar_int_mode::includes_p (machine_mod
typedef unsigned short measurement_type;
ALWAYS_INLINE scalar_float_mode () {}
- ALWAYS_INLINE scalar_float_mode (from_int m) : m_mode (machine_mode (m)) {}
- ALWAYS_INLINE operator machine_mode () const { return m_mode; }
+
+ ALWAYS_INLINE CONSTEXPR
+ scalar_float_mode (from_int m) : m_mode (machine_mode (m)) {}
+
+ ALWAYS_INLINE CONSTEXPR operator machine_mode () const { return m_mode; }
static bool includes_p (machine_mode);
@@ -453,11 +463,20 @@ scalar_float_mode::includes_p (machine_m
typedef unsigned short measurement_type;
ALWAYS_INLINE scalar_mode () {}
- ALWAYS_INLINE scalar_mode (from_int m) : m_mode (machine_mode (m)) {}
- ALWAYS_INLINE scalar_mode (const scalar_int_mode &m) : m_mode (m) {}
- ALWAYS_INLINE scalar_mode (const scalar_float_mode &m) : m_mode (m) {}
- ALWAYS_INLINE scalar_mode (const scalar_int_mode_pod &m) : m_mode (m) {}
- ALWAYS_INLINE operator machine_mode () const { return m_mode; }
+
+ ALWAYS_INLINE CONSTEXPR
+ scalar_mode (from_int m) : m_mode (machine_mode (m)) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ scalar_mode (const scalar_int_mode &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ scalar_mode (const scalar_float_mode &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ scalar_mode (const scalar_int_mode_pod &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR operator machine_mode () const { return m_mode; }
static bool includes_p (machine_mode);
@@ -494,8 +513,11 @@ scalar_mode::includes_p (machine_mode m)
typedef unsigned short measurement_type;
ALWAYS_INLINE complex_mode () {}
- ALWAYS_INLINE complex_mode (from_int m) : m_mode (machine_mode (m)) {}
- ALWAYS_INLINE operator machine_mode () const { return m_mode; }
+
+ ALWAYS_INLINE CONSTEXPR
+ complex_mode (from_int m) : m_mode (machine_mode (m)) {}
+
+ ALWAYS_INLINE CONSTEXPR operator machine_mode () const { return m_mode; }
static bool includes_p (machine_mode);
@@ -764,14 +786,29 @@ #define GET_MODE_COMPLEX_MODE(MODE) ((ma
typedef unsigned short measurement_type;
ALWAYS_INLINE fixed_size_mode () {}
- ALWAYS_INLINE fixed_size_mode (from_int m) : m_mode (machine_mode (m)) {}
- ALWAYS_INLINE fixed_size_mode (const scalar_mode &m) : m_mode (m) {}
- ALWAYS_INLINE fixed_size_mode (const scalar_int_mode &m) : m_mode (m) {}
- ALWAYS_INLINE fixed_size_mode (const scalar_float_mode &m) : m_mode (m) {}
- ALWAYS_INLINE fixed_size_mode (const scalar_mode_pod &m) : m_mode (m) {}
- ALWAYS_INLINE fixed_size_mode (const scalar_int_mode_pod &m) : m_mode (m) {}
- ALWAYS_INLINE fixed_size_mode (const complex_mode &m) : m_mode (m) {}
- ALWAYS_INLINE operator machine_mode () const { return m_mode; }
+
+ ALWAYS_INLINE CONSTEXPR
+ fixed_size_mode (from_int m) : m_mode (machine_mode (m)) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ fixed_size_mode (const scalar_mode &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ fixed_size_mode (const scalar_int_mode &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ fixed_size_mode (const scalar_float_mode &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ fixed_size_mode (const scalar_mode_pod &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ fixed_size_mode (const scalar_int_mode_pod &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR
+ fixed_size_mode (const complex_mode &m) : m_mode (m) {}
+
+ ALWAYS_INLINE CONSTEXPR operator machine_mode () const { return m_mode; }
static bool includes_p (machine_mode);
