diff options
author | Jakub Jelinek <jakub@redhat.com> | 2023-10-14 09:35:44 +0200 |
---|---|---|
committer | Jakub Jelinek <jakub@redhat.com> | 2023-10-14 09:35:44 +0200 |
commit | cb0119242317c2a6f3127b4acff6aadbfd1dfbc4 (patch) | |
tree | f84c2a0388630c4f69a56dbcb3995ba2154ea0f7 /gcc/wide-int.h | |
parent | 78dd49f387c515a6b28ef3fcb989605a168ff752 (diff) | |
download | gcc-cb0119242317c2a6f3127b4acff6aadbfd1dfbc4.zip gcc-cb0119242317c2a6f3127b4acff6aadbfd1dfbc4.tar.gz gcc-cb0119242317c2a6f3127b4acff6aadbfd1dfbc4.tar.bz2 |
middle-end: Allow _BitInt(65535) [PR102989]
The following patch lifts further restrictions which limited _BitInt to at
most 16319 bits up to 65535.
The problem was mainly in INTEGER_CST representation, which had 3
unsigned char members to describe lengths in number of 64-bit limbs, which
it wanted to fit into 32 bits. This patch removes the third one which was
just a cache to save a few compile time cycles for wi::to_offset and
enlarges the other two members to unsigned short.
Furthermore, the same problem has been in some uses of trailing_wide_int*
(in value-range-storage*) and value-range-storage* itself, while other
uses of trailing_wide_int* have been fine (e.g. CONST_POLY_INT, where no
constants will be larger than 3/5/9/11 limbs depending on target, so 255
limit is plenty). The patch turns all those length representations to be
unsigned short for consistency, so value-range-storage* can handle even
16320-65535 bits BITINT_TYPE ranges. The cc1plus growth is about 16K,
so not really significant for 38M .text section.
Note, the reason for the new limit is
unsigned int precision : 16;
TYPE_PRECISION limit, if we wanted to overcome that, TYPE_PRECISION would
need to use some other member for BITINT_TYPE from all the others and
we could reach that way 4194239 limit (65535 * 64 - 1, again implied by
INTEGER_CST and value-range-storage*). Dunno if that is
worth it or if it is something we want to do for GCC 14 though.
2023-10-14 Jakub Jelinek <jakub@redhat.com>
PR c/102989
gcc/
* tree-core.h (struct tree_base): Remove int_length.offset
member, change type of int_length.unextended and int_length.extended
from unsigned char to unsigned short.
* tree.h (TREE_INT_CST_OFFSET_NUNITS): Remove.
(wi::extended_tree <N>::get_len): Don't use TREE_INT_CST_OFFSET_NUNITS,
instead compute it at runtime from TREE_INT_CST_EXT_NUNITS and
TREE_INT_CST_NUNITS.
* tree.cc (wide_int_to_tree_1): Don't assert
TREE_INT_CST_OFFSET_NUNITS value.
(make_int_cst): Don't initialize TREE_INT_CST_OFFSET_NUNITS.
* wide-int.h (WIDE_INT_MAX_ELTS): Change from 255 to 1024.
(WIDEST_INT_MAX_ELTS): Change from 510 to 2048, adjust comment.
(trailing_wide_int_storage): Change m_len type from unsigned char *
to unsigned short *.
(trailing_wide_int_storage::trailing_wide_int_storage): Change second
argument from unsigned char * to unsigned short *.
(trailing_wide_ints): Change m_max_len type from unsigned char to
unsigned short. Change m_len element type from
struct{unsigned char len;} to unsigned short.
(trailing_wide_ints <N>::operator []): Remove .len from m_len
accesses.
* value-range-storage.h (irange_storage::lengths_address): Change
return type from const unsigned char * to const unsigned short *.
(irange_storage::write_lengths_address): Change return type from
unsigned char * to unsigned short *.
* value-range-storage.cc (irange_storage::write_lengths_address):
Likewise.
(irange_storage::lengths_address): Change return type from
const unsigned char * to const unsigned short *.
(write_wide_int): Change len argument type from unsigned char *&
to unsigned short *&.
(irange_storage::set_irange): Change len variable type from
unsigned char * to unsigned short *.
(read_wide_int): Change len argument type from unsigned char to
unsigned short. Use trailing_wide_int_storage <unsigned short>
instead of trailing_wide_int_storage and
trailing_wide_int <unsigned short> instead of trailing_wide_int.
(irange_storage::get_irange): Change len variable type from
unsigned char * to unsigned short *.
(irange_storage::size): Multiply n by sizeof (unsigned short)
in len_size variable initialization.
(irange_storage::dump): Change len variable type from
unsigned char * to unsigned short *.
gcc/cp/
* module.cc (trees_out::start, trees_in::start): Remove
TREE_INT_CST_OFFSET_NUNITS handling.
gcc/testsuite/
* gcc.dg/bitint-38.c: Change into dg-do run test, in addition
to checking the addition, division and right shift results at compile
time check it also at runtime.
* gcc.dg/bitint-39.c: New test.
Diffstat (limited to 'gcc/wide-int.h')
-rw-r--r-- | gcc/wide-int.h | 25 |
1 files changed, 11 insertions, 14 deletions
diff --git a/gcc/wide-int.h b/gcc/wide-int.h index 07bacc9..73e431d 100644 --- a/gcc/wide-int.h +++ b/gcc/wide-int.h @@ -249,12 +249,11 @@ along with GCC; see the file COPYING3. If not see /* Precision of wide_int and largest _BitInt precision + 1 we can support. */ -#define WIDE_INT_MAX_ELTS 255 +#define WIDE_INT_MAX_ELTS 1024 #define WIDE_INT_MAX_PRECISION (WIDE_INT_MAX_ELTS * HOST_BITS_PER_WIDE_INT) -/* Precision of widest_int and largest _BitInt precision + 1 we can - support. */ -#define WIDEST_INT_MAX_ELTS 510 +/* Precision of widest_int. */ +#define WIDEST_INT_MAX_ELTS 2048 #define WIDEST_INT_MAX_PRECISION (WIDEST_INT_MAX_ELTS * HOST_BITS_PER_WIDE_INT) STATIC_ASSERT (WIDE_INT_MAX_INL_ELTS < WIDE_INT_MAX_ELTS); @@ -1717,14 +1716,14 @@ private: unsigned int m_precision; /* A pointer to the length field. */ - unsigned char *m_len; + unsigned short *m_len; /* A pointer to the HWI array. There are enough elements to hold all values of precision M_PRECISION. */ HOST_WIDE_INT *m_val; public: - trailing_wide_int_storage (unsigned int, unsigned char *, HOST_WIDE_INT *); + trailing_wide_int_storage (unsigned int, unsigned short *, HOST_WIDE_INT *); /* The standard generic_wide_int storage methods. */ unsigned int get_len () const; @@ -1762,15 +1761,13 @@ private: unsigned short m_precision; /* The shared maximum length of each number. */ - unsigned char m_max_len; + unsigned short m_max_len; /* The number of elements. */ unsigned char m_num_elements; - /* The current length of each number. - Avoid char array so the whole structure is not a typeless storage - that will, in turn, turn off TBAA on gimple, trees and RTL. */ - struct {unsigned char len;} m_len[N]; + /* The current length of each number. */ + unsigned short m_len[N]; /* The variable-length part of the structure, which always contains at least one HWI. Element I starts at index I * M_MAX_LEN. */ @@ -1791,7 +1788,7 @@ public: }; inline trailing_wide_int_storage:: -trailing_wide_int_storage (unsigned int precision, unsigned char *len, +trailing_wide_int_storage (unsigned int precision, unsigned short *len, HOST_WIDE_INT *val) : m_precision (precision), m_len (len), m_val (val) { @@ -1857,7 +1854,7 @@ template <int N> inline trailing_wide_int trailing_wide_ints <N>::operator [] (unsigned int index) { - return trailing_wide_int_storage (m_precision, &m_len[index].len, + return trailing_wide_int_storage (m_precision, &m_len[index], &m_val[index * m_max_len]); } @@ -1866,7 +1863,7 @@ inline typename trailing_wide_ints <N>::const_reference trailing_wide_ints <N>::operator [] (unsigned int index) const { return wi::storage_ref (&m_val[index * m_max_len], - m_len[index].len, m_precision); + m_len[index], m_precision); } /* Return how many extra bytes need to be added to the end of the |