Commit e8be4f44 authored by Paul Eggert's avatar Paul Eggert

Port USE_LOCAL_ALLOCATORS code to clang 3.4 x86-64.

Revert previous lisp.h change, and install the following instead.
* lisp.h (USE_LOCAL_ALLOCATORS): Define only if __GNUC__ &&
!__clang__.  This works with GCC and with clang and is safer for
compilers we don't know about.
parent bb95ed98
2014-09-18 Paul Eggert <eggert@cs.ucla.edu>
Port USE_LOCAL_ALLOCATORS code to clang 3.4 x86-64.
* lisp.h (ALLOCA_FIXUP): New constant.
(LOCAL_ALLOCA): New macro.
(local_cons, make_local_vector, make_local_string): Use them.
* lisp.h (USE_LOCAL_ALLOCATORS): Define only if __GNUC__ &&
!__clang__. This works with GCC and with clang and is safer for
compilers we don't know about.
(local_cons): Rename parameter to make capture less likely.
2014-09-17 Samuel Bronson <naesten@gmail.com>
......
......@@ -4599,30 +4599,22 @@ verify (sizeof (struct Lisp_Cons) == sizeof (union Aligned_Cons));
# define scoped_list3(x, y, z) list3 (x, y, z)
#endif
#if USE_STACK_LISP_OBJECTS && HAVE_STATEMENT_EXPRESSIONS
/* Local allocators require both statement expressions and a
GCALIGNMENT-aligned alloca. clang's alloca isn't properly aligned
in some cases. In the absence of solid information, play it safe
for other non-GCC compilers. */
#if (USE_STACK_LISP_OBJECTS && HAVE_STATEMENT_EXPRESSIONS \
&& __GNUC__ && !__clang__)
# define USE_LOCAL_ALLOCATORS
#endif
/* Alignment fixup needed for alloca. GCC aligns alloca properly already,
Clang sometimes doesn't, and play it safe for other random compilers. */
# if __GNUC__ && !__clang__
enum { ALLOCA_FIXUP = 0 };
# else
enum { ALLOCA_FIXUP = GCALIGNMENT - 1 };
# endif
/* Declare a void * variable PTR and set it to a properly-aligned array of
N newly allocated bytes with function lifetime. */
# define LOCAL_ALLOCA(ptr, n) \
void *ptr = alloca ((n) + ALLOCA_FIXUP); \
ptr = (void *) ((intptr_t) ptr_ & ~(ALLOCA_FIXUP))
#ifdef USE_LOCAL_ALLOCATORS
/* Return a function-scoped cons whose car is X and cdr is Y. */
# define local_cons(x, y) \
({ \
LOCAL_ALLOCA (ptr_, sizeof (struct Lisp_Cons)); \
struct Lisp_Cons *c_ = ptr_; \
struct Lisp_Cons *c_ = alloca (sizeof (struct Lisp_Cons)); \
c_->car = (x); \
c_->u.cdr = (y); \
make_lisp_ptr (c_, Lisp_Cons); \
......@@ -4640,9 +4632,9 @@ enum { ALLOCA_FIXUP = GCALIGNMENT - 1 };
ptrdiff_t size_ = size; \
Lisp_Object init_ = init; \
Lisp_Object vec_; \
if (size_ <= (MAX_ALLOCA - ALLOCA_FIXUP - header_size) / word_size) \
if (size_ <= (MAX_ALLOCA - header_size) / word_size) \
{ \
LOCAL_ALLOCA (ptr_, size_ * word_size + header_size); \
void *ptr_ = alloca (size_ * word_size + header_size); \
vec_ = local_vector_init (ptr_, size_, init_); \
} \
else \
......@@ -4657,10 +4649,10 @@ enum { ALLOCA_FIXUP = GCALIGNMENT - 1 };
char const *data_ = data; \
ptrdiff_t nbytes_ = nbytes; \
Lisp_Object string_; \
if (nbytes_ \
<= MAX_ALLOCA - ALLOCA_FIXUP - sizeof (struct Lisp_String) - 1) \
if (nbytes_ <= MAX_ALLOCA - sizeof (struct Lisp_String) - 1) \
{ \
LOCAL_ALLOCA (ptr_, sizeof (struct Lisp_String) + 1 + bytes_); \
struct Lisp_String *ptr_ \
= alloca (sizeof (struct Lisp_String) + 1 + nbytes_); \
string_ = local_string_init (ptr_, data_, nbytes_); \
} \
else \
......
Markdown is supported
0% or
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment