1/* A class for building vector rtx constants.
2 Copyright (C) 2017-2025 Free Software Foundation, Inc.
3
4This file is part of GCC.
5
6GCC is free software; you can redistribute it and/or modify it under
7the terms of the GNU General Public License as published by the Free
8Software Foundation; either version 3, or (at your option) any later
9version.
10
11GCC is distributed in the hope that it will be useful, but WITHOUT ANY
12WARRANTY; without even the implied warranty of MERCHANTABILITY or
13FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
14for more details.
15
16You should have received a copy of the GNU General Public License
17along with GCC; see the file COPYING3. If not see
18<http://www.gnu.org/licenses/>. */
19
20#include "config.h"
21#include "system.h"
22#include "coretypes.h"
23#include "tm.h"
24#include "rtl.h"
25#include "rtx-vector-builder.h"
26
27/* Return a CONST_VECTOR for the current constant. V is an existing
28 rtvec that contains all the elements. */
29
30rtx
31rtx_vector_builder::build (rtvec v)
32{
33 finalize ();
34
35 rtx x = find_cached_value ();
36 if (x)
37 return x;
38
39 x = gen_rtx_raw_CONST_VECTOR (m_mode, v);
40 CONST_VECTOR_NPATTERNS (x) = npatterns ();
41 CONST_VECTOR_NELTS_PER_PATTERN (x) = nelts_per_pattern ();
42 return x;
43}
44
45/* Return a vector element with the value BASE + FACTOR * STEP. */
46
47rtx
48rtx_vector_builder::apply_step (rtx base, unsigned int factor,
49 const poly_wide_int &step) const
50{
51 scalar_int_mode int_mode = as_a <scalar_int_mode> (GET_MODE_INNER (m_mode));
52 return immed_wide_int_const (wi::to_poly_wide (x: base, mode: int_mode)
53 + factor * step,
54 int_mode);
55}
56
57/* Return a CONST_VECTOR for the current constant. */
58
59rtx
60rtx_vector_builder::build ()
61{
62 finalize ();
63
64 rtx x = find_cached_value ();
65 if (x)
66 return x;
67
68 unsigned int nelts;
69 if (!GET_MODE_NUNITS (mode: m_mode).is_constant (const_value: &nelts))
70 nelts = encoded_nelts ();
71 rtvec v = rtvec_alloc (nelts);
72 for (unsigned int i = 0; i < nelts; ++i)
73 RTVEC_ELT (v, i) = elt (i);
74 x = gen_rtx_raw_CONST_VECTOR (m_mode, v);
75 CONST_VECTOR_NPATTERNS (x) = npatterns ();
76 CONST_VECTOR_NELTS_PER_PATTERN (x) = nelts_per_pattern ();
77 return x;
78}
79
80/* Check whether there is a global cached value for the vector.
81 Return it if so, otherwise return null. */
82
83rtx
84rtx_vector_builder::find_cached_value ()
85{
86 if (encoded_nelts () != 1)
87 return NULL_RTX;
88
89 rtx elt = (*this)[0];
90
91 if (GET_MODE_CLASS (m_mode) == MODE_VECTOR_BOOL)
92 {
93 if (elt == const1_rtx)
94 return CONST1_RTX (m_mode);
95 else if (elt == constm1_rtx)
96 return CONSTM1_RTX (m_mode);
97 else if (elt == const0_rtx)
98 return CONST0_RTX (m_mode);
99 else
100 gcc_unreachable ();
101 }
102
103 /* We can be called before the global vector constants are set up,
104 but in that case we'll just return null. */
105 scalar_mode inner_mode = GET_MODE_INNER (m_mode);
106 if (elt == CONST0_RTX (inner_mode))
107 return CONST0_RTX (m_mode);
108 else if (elt == CONST1_RTX (inner_mode))
109 return CONST1_RTX (m_mode);
110 else if (elt == CONSTM1_RTX (inner_mode))
111 return CONSTM1_RTX (m_mode);
112
113 return NULL_RTX;
114}
115

source code of gcc/rtx-vector-builder.cc