diff options
Diffstat (limited to 'src/alloc.c')
| -rw-r--r-- | src/alloc.c | 108 |
1 files changed, 53 insertions, 55 deletions
diff --git a/src/alloc.c b/src/alloc.c index b35f7c4333f..7054083acba 100644 --- a/src/alloc.c +++ b/src/alloc.c @@ -361,13 +361,21 @@ static int staticidx; static void *pure_alloc (size_t, int); +/* Return X rounded to the next multiple of Y. Arguments should not + have side effects, as they are evaluated more than once. Assume X + + Y - 1 does not overflow. Tune for Y being a power of 2. */ -/* Value is SZ rounded up to the next multiple of ALIGNMENT. - ALIGNMENT must be a power of 2. */ +#define ROUNDUP(x, y) ((y) & ((y) - 1) \ + ? ((x) + (y) - 1) - ((x) + (y) - 1) % (y) \ + : ((x) + (y) - 1) & ~ ((y) - 1)) -#define ALIGN(ptr, ALIGNMENT) \ - ((void *) (((uintptr_t) (ptr) + (ALIGNMENT) - 1) \ - & ~ ((ALIGNMENT) - 1))) +/* Return PTR rounded up to the next multiple of ALIGNMENT. */ + +static void * +ALIGN (void *ptr, int alignment) +{ + return (void *) ROUNDUP ((uintptr_t) ptr, alignment); +} static void XFLOAT_INIT (Lisp_Object f, double n) @@ -2026,33 +2034,39 @@ INIT must be an integer that represents a character. */) return val; } -verify (sizeof (size_t) * CHAR_BIT == BITS_PER_BITS_WORD); -verify ((BITS_PER_BITS_WORD & (BITS_PER_BITS_WORD - 1)) == 0); - -static ptrdiff_t -bool_vector_payload_bytes (ptrdiff_t nr_bits, - ptrdiff_t *exact_needed_bytes_out) +static EMACS_INT +bool_vector_exact_payload_bytes (EMACS_INT nbits) { - ptrdiff_t exact_needed_bytes; - ptrdiff_t needed_bytes; + eassume (0 <= nbits); + return (nbits + BOOL_VECTOR_BITS_PER_CHAR - 1) / BOOL_VECTOR_BITS_PER_CHAR; +} - eassume (nr_bits >= 0); +static EMACS_INT +bool_vector_payload_bytes (EMACS_INT nbits) +{ + EMACS_INT exact_needed_bytes = bool_vector_exact_payload_bytes (nbits); - exact_needed_bytes = ROUNDUP ((size_t) nr_bits, CHAR_BIT) / CHAR_BIT; - needed_bytes = ROUNDUP ((size_t) nr_bits, BITS_PER_BITS_WORD) / CHAR_BIT; + /* Always allocate at least one machine word of payload so that + bool-vector operations in data.c don't need a special case + for empty vectors. */ + return ROUNDUP (exact_needed_bytes + !exact_needed_bytes, + sizeof (bits_word)); +} - if (needed_bytes == 0) +void +bool_vector_fill (Lisp_Object a, Lisp_Object init) +{ + EMACS_INT nbits = bool_vector_size (a); + if (0 < nbits) { - /* Always allocate at least one machine word of payload so that - bool-vector operations in data.c don't need a special case - for empty vectors. */ - needed_bytes = sizeof (bits_word); + unsigned char *data = bool_vector_uchar_data (a); + int pattern = NILP (init) ? 0 : (1 << BOOL_VECTOR_BITS_PER_CHAR) - 1; + ptrdiff_t nbytes = ((nbits + BOOL_VECTOR_BITS_PER_CHAR - 1) + / BOOL_VECTOR_BITS_PER_CHAR); + int last_mask = ~ (~0 << ((nbits - 1) % BOOL_VECTOR_BITS_PER_CHAR + 1)); + memset (data, pattern, nbytes - 1); + data[nbytes - 1] = pattern & last_mask; } - - if (exact_needed_bytes_out != NULL) - *exact_needed_bytes_out = exact_needed_bytes; - - return needed_bytes; } DEFUN ("make-bool-vector", Fmake_bool_vector, Smake_bool_vector, 2, 2, 0, @@ -2060,42 +2074,29 @@ DEFUN ("make-bool-vector", Fmake_bool_vector, Smake_bool_vector, 2, 2, 0, LENGTH must be a number. INIT matters only in whether it is t or nil. */) (Lisp_Object length, Lisp_Object init) { - register Lisp_Object val; + Lisp_Object val; struct Lisp_Bool_Vector *p; - ptrdiff_t exact_payload_bytes; - ptrdiff_t total_payload_bytes; - ptrdiff_t needed_elements; + EMACS_INT exact_payload_bytes, total_payload_bytes, needed_elements; CHECK_NATNUM (length); - if (PTRDIFF_MAX < XFASTINT (length)) - memory_full (SIZE_MAX); - - total_payload_bytes = bool_vector_payload_bytes - (XFASTINT (length), &exact_payload_bytes); - eassume (exact_payload_bytes <= total_payload_bytes); - eassume (0 <= exact_payload_bytes); + exact_payload_bytes = bool_vector_exact_payload_bytes (XFASTINT (length)); + total_payload_bytes = bool_vector_payload_bytes (XFASTINT (length)); - needed_elements = ROUNDUP ((size_t) ((bool_header_size - header_size) - + total_payload_bytes), - word_size) / word_size; + needed_elements = ((bool_header_size - header_size + total_payload_bytes + + word_size - 1) + / word_size); p = (struct Lisp_Bool_Vector *) allocate_vector (needed_elements); XSETVECTOR (val, p); XSETPVECTYPESIZE (XVECTOR (val), PVEC_BOOL_VECTOR, 0, 0); p->size = XFASTINT (length); - if (exact_payload_bytes) - { - memset (p->data, ! NILP (init) ? -1 : 0, exact_payload_bytes); - - /* Clear any extraneous bits in the last byte. */ - p->data[exact_payload_bytes - 1] - &= (1 << ((XFASTINT (length) - 1) % BOOL_VECTOR_BITS_PER_CHAR + 1)) - 1; - } + bool_vector_fill (val, init); /* Clear padding at the end. */ - memset (p->data + exact_payload_bytes, + eassume (exact_payload_bytes <= total_payload_bytes); + memset (bool_vector_uchar_data (val) + exact_payload_bytes, 0, total_payload_bytes - exact_payload_bytes); @@ -2648,7 +2649,7 @@ verify ((VECTOR_BLOCK_SIZE % roundup_size) == 0); verify (VECTOR_BLOCK_SIZE <= (1 << PSEUDOVECTOR_SIZE_BITS)); /* Round up X to nearest mult-of-ROUNDUP_SIZE --- use at compile time. */ -#define vroundup_ct(x) ROUNDUP ((size_t) (x), roundup_size) +#define vroundup_ct(x) ROUNDUP (x, roundup_size) /* Round up X to nearest mult-of-ROUNDUP_SIZE --- use at runtime. */ #define vroundup(x) (eassume ((x) >= 0), vroundup_ct (x)) @@ -2856,11 +2857,8 @@ vector_nbytes (struct Lisp_Vector *v) if (PSEUDOVECTOR_TYPEP (&v->header, PVEC_BOOL_VECTOR)) { struct Lisp_Bool_Vector *bv = (struct Lisp_Bool_Vector *) v; - ptrdiff_t payload_bytes = - bool_vector_payload_bytes (bv->size, NULL); - - eassume (payload_bytes >= 0); - size = bool_header_size + ROUNDUP (payload_bytes, word_size); + ptrdiff_t payload_bytes = bool_vector_payload_bytes (bv->size); + size = bool_header_size + payload_bytes; } else size = (header_size |