Mercurial > projects > ldc
view dmd2/mem.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 | f04dde6e882c |
children |
line wrap: on
line source
// Copyright (C) 2000-2001 by Chromium Communications // All Rights Reserved #ifndef ROOT_MEM_H #define ROOT_MEM_H #include <stddef.h> // for size_t typedef void (*FINALIZERPROC)(void* pObj, void* pClientData); struct GC; // thread specific allocator struct Mem { GC *gc; // pointer to our thread specific allocator Mem() { gc = NULL; } void init(); // Derive from Mem to get these storage allocators instead of global new/delete void * operator new(size_t m_size); void * operator new(size_t m_size, Mem *mem); void * operator new(size_t m_size, GC *gc); void operator delete(void *p); void * operator new[](size_t m_size); void operator delete[](void *p); char *strdup(const char *s); void *malloc(size_t size); void *malloc_uncollectable(size_t size); void *calloc(size_t size, size_t n); void *realloc(void *p, size_t size); void free(void *p); void free_uncollectable(void *p); void *mallocdup(void *o, size_t size); void error(); void check(void *p); // validate pointer void fullcollect(); // do full garbage collection void fullcollectNoStack(); // do full garbage collection, no scan stack void mark(void *pointer); void addroots(char* pStart, char* pEnd); void removeroots(char* pStart); void setFinalizer(void* pObj, FINALIZERPROC pFn, void* pClientData); void setStackBottom(void *bottom); GC *getThreadGC(); // get apartment allocator for this thread }; extern Mem mem; #endif /* ROOT_MEM_H */