1 /*
2 * Copyright (C) 2021 Collabora Ltd.
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
20 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
21 * SOFTWARE.
22 */
23
24 #include "bi_builder.h"
25 #include "va_compiler.h"
26
27 /*
28 * Bifrost uses split 64-bit addresses, specified as two consecutive sources.
29 * Valhall uses contiguous 64-bit addresses, specified as a single source with
30 * an aligned register pair. This simple pass inserts moves to lower split
31 * 64-bit sources into a collect, ensuring the register constraints will be
32 * respected by RA. This could be optimized, but this is deferred for now.
33 */
34 static void
lower_split_src(bi_context * ctx,bi_instr * I,unsigned s)35 lower_split_src(bi_context *ctx, bi_instr *I, unsigned s)
36 {
37 /* Skip sources that are already split properly */
38 bi_index offset_fau = I->src[s];
39 offset_fau.offset++;
40
41 if (I->src[s].type == BI_INDEX_FAU && I->src[s].offset == 0 &&
42 bi_is_value_equiv(offset_fau, I->src[s + 1])) {
43 return;
44 }
45
46 /* Allocate temporary before the instruction */
47 bi_builder b = bi_init_builder(ctx, bi_before_instr(I));
48 bi_index vec = bi_temp(ctx);
49 bi_instr *collect = bi_collect_i32_to(&b, vec, 2);
50 bi_instr *split = bi_split_i32_to(&b, 2, vec);
51
52 /* Emit collect */
53 for (unsigned w = 0; w < 2; ++w) {
54 collect->src[w] = I->src[s + w];
55
56 split->dest[w] = bi_temp(ctx);
57 I->src[s + w] = split->dest[w];
58 }
59 }
60
61 void
va_lower_split_64bit(bi_context * ctx)62 va_lower_split_64bit(bi_context *ctx)
63 {
64 bi_foreach_instr_global(ctx, I) {
65 bi_foreach_src(I, s) {
66 if (bi_is_null(I->src[s]) || s >= 4)
67 continue;
68
69 struct va_src_info info = va_src_info(I->op, s);
70
71 if (info.size == VA_SIZE_64)
72 lower_split_src(ctx, I, s);
73 }
74 }
75 }
76