Mercurial > projects > ldc
view dmd/port.h @ 1117:4c20fcc4252b
Fun with parameter attributes: For several of the "synthetic" parameters added
to D functions, we can apply noalias and nocapture. They are sret parameters,
'nest' pointers passed to nested functions, and _argptr:
Nocapture:
- Sret and nest are nocapture because they don't represent D-level variables,
and thus the callee can't (validly) obtain a pointer to them, let alone keep
it around after it returns.
- _argptr is nocapture because although the callee has access to it as a
pointer, that pointer is invalidated when it returns.
All three are noalias because they're function-local variables
- Sret and _argptr are noalias because they're freshly alloca'd memory only
used for a single function call that's not allowed to keep an aliasing
pointer to it around (since the parameter is nocapture).
- 'Nest' is noalias because the callee only ever has access to one such pointer
per parent function, and every parent function has a different one.
This commit also ensures attributes set on sret, _arguments and _argptr are
propagated to calls to such functions.
It also adds one exception to the general rule that attributes on function types
should propagate to calls: the type of a delegate's function pointer has a
'nest' parameter, but this can either be a true 'nest' (for delegates to nested
functions) or a 'this' (for delegates to member functions). Since 'this' is
neither noalias nor nocapture, and there's generally no way to tell which one it
is, we remove these attributes at the call site if the callee is a delegate.
author | Frits van Bommel <fvbommel wxs.nl> |
---|---|
date | Sat, 14 Mar 2009 22:15:31 +0100 |
parents | c53b6e3fe49a |
children |
line wrap: on
line source
// Copyright (c) 1999-2002 by Digital Mars // All Rights Reserved // written by Walter Bright // www.digitalmars.com #ifndef PORT_H #define PORT_H // Portable wrapper around compiler/system specific things. // The idea is to minimize #ifdef's in the app code. #ifndef TYPEDEFS #define TYPEDEFS #include <wchar.h> #if _MSC_VER typedef __int64 longlong; typedef unsigned __int64 ulonglong; #else typedef long long longlong; typedef unsigned long long ulonglong; #endif #endif typedef double d_time; struct Port { static double nan; static double infinity; static double dbl_max; static double dbl_min; #if __GNUC__ // These conflict with macros in math.h, should rename them #undef isnan #undef isfinite #undef isinfinity #undef signbit #endif static int isNan(double); static int isFinite(double); static int isInfinity(double); static int Signbit(double); static double floor(double); static double pow(double x, double y); static ulonglong strtoull(const char *p, char **pend, int base); static char *ull_to_string(char *buffer, ulonglong ull); static wchar_t *ull_to_string(wchar_t *buffer, ulonglong ull); // Convert ulonglong to double static double ull_to_double(ulonglong ull); // Get locale-dependent list separator static char *list_separator(); static wchar_t *wlist_separator(); }; #endif