xref: /aosp_15_r20/external/mesa3d/src/panfrost/midgard/disassemble.c (revision 6104692788411f58d303aa86923a9ff6ecaded22)
1 /* Author(s):
2  *   Connor Abbott
3  *   Alyssa Rosenzweig
4  *
5  * Copyright (c) 2013 Connor Abbott ([email protected])
6  * Copyright (c) 2018 Alyssa Rosenzweig ([email protected])
7  * Copyright (C) 2019-2020 Collabora, Ltd.
8  *
9  * Permission is hereby granted, free of charge, to any person obtaining a copy
10  * of this software and associated documentation files (the "Software"), to deal
11  * in the Software without restriction, including without limitation the rights
12  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
13  * copies of the Software, and to permit persons to whom the Software is
14  * furnished to do so, subject to the following conditions:
15  *
16  * The above copyright notice and this permission notice shall be included in
17  * all copies or substantial portions of the Software.
18  *
19  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
20  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
21  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
22  * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
23  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
24  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
25  * THE SOFTWARE.
26  */
27 
28 #include "disassemble.h"
29 #include <assert.h>
30 #include <ctype.h>
31 #include <inttypes.h>
32 #include <stdint.h>
33 #include <stdio.h>
34 #include <stdlib.h>
35 #include <string.h>
36 #include "util/bitscan.h"
37 #include "util/half_float.h"
38 #include "util/u_math.h"
39 #include "helpers.h"
40 #include "midgard.h"
41 #include "midgard_ops.h"
42 #include "midgard_quirks.h"
43 
44 #define DEFINE_CASE(define, str)                                               \
45    case define: {                                                              \
46       fprintf(fp, str);                                                        \
47       break;                                                                   \
48    }
49 
50 /* These are not mapped to hardware values, they just represent the possible
51  * implicit arg modifiers that some midgard opcodes have, which can be decoded
52  * from the opcodes via midgard_{alu,ldst,tex}_special_arg_mod() */
53 typedef enum {
54    midgard_arg_mod_none = 0,
55    midgard_arg_mod_inv,
56    midgard_arg_mod_x2,
57 } midgard_special_arg_mod;
58 
59 typedef struct {
60    unsigned *midg_tags;
61 
62    /* For static analysis to ensure all registers are written at least once
63     * before use along the source code path (TODO: does this break done for
64     * complex CF?)
65     */
66 
67    uint16_t midg_ever_written;
68 } disassemble_context;
69 
70 /* Transform an expanded writemask (duplicated 8-bit format) into its condensed
71  * form (one bit per component) */
72 
73 static inline unsigned
condense_writemask(unsigned expanded_mask,unsigned bits_per_component)74 condense_writemask(unsigned expanded_mask, unsigned bits_per_component)
75 {
76    if (bits_per_component == 8) {
77       /* Duplicate every bit to go from 8 to 16-channel wrmask */
78       unsigned omask = 0;
79 
80       for (unsigned i = 0; i < 8; ++i) {
81          if (expanded_mask & (1 << i))
82             omask |= (3 << (2 * i));
83       }
84 
85       return omask;
86    }
87 
88    unsigned slots_per_component = bits_per_component / 16;
89    unsigned max_comp = (16 * 8) / bits_per_component;
90    unsigned condensed_mask = 0;
91 
92    for (unsigned i = 0; i < max_comp; i++) {
93       if (expanded_mask & (1 << (i * slots_per_component)))
94          condensed_mask |= (1 << i);
95    }
96 
97    return condensed_mask;
98 }
99 
100 static bool
print_alu_opcode(FILE * fp,midgard_alu_op op)101 print_alu_opcode(FILE *fp, midgard_alu_op op)
102 {
103    if (alu_opcode_props[op].name)
104       fprintf(fp, "%s", alu_opcode_props[op].name);
105    else
106       fprintf(fp, "alu_op_%02X", op);
107 
108    /* For constant analysis */
109    return midgard_is_integer_op(op);
110 }
111 
112 static void
print_ld_st_opcode(FILE * fp,midgard_load_store_op op)113 print_ld_st_opcode(FILE *fp, midgard_load_store_op op)
114 {
115    if (load_store_opcode_props[op].name)
116       fprintf(fp, "%s", load_store_opcode_props[op].name);
117    else
118       fprintf(fp, "ldst_op_%02X", op);
119 }
120 
121 static void
validate_sampler_type(enum mali_texture_op op,enum mali_sampler_type sampler_type)122 validate_sampler_type(enum mali_texture_op op,
123                       enum mali_sampler_type sampler_type)
124 {
125    if (op == midgard_tex_op_mov || op == midgard_tex_op_barrier)
126       assert(sampler_type == 0);
127    else
128       assert(sampler_type > 0);
129 }
130 
131 static void
validate_expand_mode(midgard_src_expand_mode expand_mode,midgard_reg_mode reg_mode)132 validate_expand_mode(midgard_src_expand_mode expand_mode,
133                      midgard_reg_mode reg_mode)
134 {
135    switch (expand_mode) {
136    case midgard_src_passthrough:
137       break;
138 
139    case midgard_src_rep_low:
140       assert(reg_mode == midgard_reg_mode_8 || reg_mode == midgard_reg_mode_16);
141       break;
142 
143    case midgard_src_rep_high:
144       assert(reg_mode == midgard_reg_mode_8 || reg_mode == midgard_reg_mode_16);
145       break;
146 
147    case midgard_src_swap:
148       assert(reg_mode == midgard_reg_mode_8 || reg_mode == midgard_reg_mode_16);
149       break;
150 
151    case midgard_src_expand_low:
152       assert(reg_mode != midgard_reg_mode_8);
153       break;
154 
155    case midgard_src_expand_high:
156       assert(reg_mode != midgard_reg_mode_8);
157       break;
158 
159    case midgard_src_expand_low_swap:
160       assert(reg_mode == midgard_reg_mode_16);
161       break;
162 
163    case midgard_src_expand_high_swap:
164       assert(reg_mode == midgard_reg_mode_16);
165       break;
166 
167    default:
168       unreachable("Invalid expand mode");
169       break;
170    }
171 }
172 
173 static void
print_alu_reg(disassemble_context * ctx,FILE * fp,unsigned reg,bool is_write)174 print_alu_reg(disassemble_context *ctx, FILE *fp, unsigned reg, bool is_write)
175 {
176    unsigned uniform_reg = 23 - reg;
177    bool is_uniform = false;
178 
179    /* For r8-r15, it could be a work or uniform. We distinguish based on
180     * the fact work registers are ALWAYS written before use, but uniform
181     * registers are NEVER written before use. */
182 
183    if ((reg >= 8 && reg < 16) && !(ctx->midg_ever_written & (1 << reg)))
184       is_uniform = true;
185 
186    /* r16-r23 are always uniform */
187 
188    if (reg >= 16 && reg <= 23)
189       is_uniform = true;
190 
191    if (reg == REGISTER_UNUSED || reg == REGISTER_UNUSED + 1)
192       fprintf(fp, "TMP%u", reg - REGISTER_UNUSED);
193    else if (reg == REGISTER_TEXTURE_BASE || reg == REGISTER_TEXTURE_BASE + 1)
194       fprintf(fp, "%s%u", is_write ? "AT" : "TA", reg - REGISTER_TEXTURE_BASE);
195    else if (reg == REGISTER_LDST_BASE || reg == REGISTER_LDST_BASE + 1)
196       fprintf(fp, "AL%u", reg - REGISTER_LDST_BASE);
197    else if (is_uniform)
198       fprintf(fp, "U%u", uniform_reg);
199    else if (reg == 31 && !is_write)
200       fprintf(fp, "PC_SP");
201    else
202       fprintf(fp, "R%u", reg);
203 }
204 
205 static void
print_ldst_write_reg(FILE * fp,unsigned reg)206 print_ldst_write_reg(FILE *fp, unsigned reg)
207 {
208    switch (reg) {
209    case 26:
210    case 27:
211       fprintf(fp, "AL%u", reg - REGISTER_LDST_BASE);
212       break;
213    case 28:
214    case 29:
215       fprintf(fp, "AT%u", reg - REGISTER_TEXTURE_BASE);
216       break;
217    case 31:
218       fprintf(fp, "PC_SP");
219       break;
220    default:
221       fprintf(fp, "R%d", reg);
222       break;
223    }
224 }
225 
226 static void
print_ldst_read_reg(FILE * fp,unsigned reg)227 print_ldst_read_reg(FILE *fp, unsigned reg)
228 {
229    switch (reg) {
230    case 0:
231    case 1:
232       fprintf(fp, "AL%u", reg);
233       break;
234    case 2:
235       fprintf(fp, "PC_SP");
236       break;
237    case 3:
238       fprintf(fp, "LOCAL_STORAGE_PTR");
239       break;
240    case 4:
241       fprintf(fp, "LOCAL_THREAD_ID");
242       break;
243    case 5:
244       fprintf(fp, "GROUP_ID");
245       break;
246    case 6:
247       fprintf(fp, "GLOBAL_THREAD_ID");
248       break;
249    case 7:
250       fprintf(fp, "0");
251       break;
252    default:
253       unreachable("Invalid load/store register read");
254    }
255 }
256 
257 static void
print_tex_reg(FILE * fp,unsigned reg,bool is_write)258 print_tex_reg(FILE *fp, unsigned reg, bool is_write)
259 {
260    char *str = is_write ? "TA" : "AT";
261    int select = reg & 1;
262 
263    switch (reg) {
264    case 0:
265    case 1:
266       fprintf(fp, "R%d", select);
267       break;
268    case 26:
269    case 27:
270       fprintf(fp, "AL%d", select);
271       break;
272    case 28:
273    case 29:
274       fprintf(fp, "%s%d", str, select);
275       break;
276    default:
277       unreachable("Invalid texture register");
278    }
279 }
280 
281 static char *srcmod_names_int[4] = {
282    ".sext",
283    ".zext",
284    ".replicate",
285    ".lshift",
286 };
287 
288 static char *argmod_names[3] = {
289    "",
290    ".inv",
291    ".x2",
292 };
293 
294 static char *index_format_names[4] = {"", ".u64", ".u32", ".s32"};
295 
296 static void
print_alu_outmod(FILE * fp,unsigned outmod,bool is_int,bool half)297 print_alu_outmod(FILE *fp, unsigned outmod, bool is_int, bool half)
298 {
299    if (is_int && !half) {
300       assert(outmod == midgard_outmod_keeplo);
301       return;
302    }
303 
304    if (!is_int && half)
305       fprintf(fp, ".shrink");
306 
307    mir_print_outmod(fp, outmod, is_int);
308 }
309 
310 /* arg == 0 (dest), arg == 1 (src1), arg == 2 (src2) */
311 static midgard_special_arg_mod
midgard_alu_special_arg_mod(midgard_alu_op op,unsigned arg)312 midgard_alu_special_arg_mod(midgard_alu_op op, unsigned arg)
313 {
314    midgard_special_arg_mod mod = midgard_arg_mod_none;
315 
316    switch (op) {
317    case midgard_alu_op_ishladd:
318    case midgard_alu_op_ishlsub:
319       if (arg == 1)
320          mod = midgard_arg_mod_x2;
321       break;
322 
323    default:
324       break;
325    }
326 
327    return mod;
328 }
329 
330 static void
print_quad_word(FILE * fp,const uint32_t * words,unsigned tabs)331 print_quad_word(FILE *fp, const uint32_t *words, unsigned tabs)
332 {
333    unsigned i;
334 
335    for (i = 0; i < 4; i++)
336       fprintf(fp, "0x%08X%s ", words[i], i == 3 ? "" : ",");
337 
338    fprintf(fp, "\n");
339 }
340 
341 static const char components[16] = "xyzwefghijklmnop";
342 
343 static int
bits_for_mode(midgard_reg_mode mode)344 bits_for_mode(midgard_reg_mode mode)
345 {
346    switch (mode) {
347    case midgard_reg_mode_8:
348       return 8;
349    case midgard_reg_mode_16:
350       return 16;
351    case midgard_reg_mode_32:
352       return 32;
353    case midgard_reg_mode_64:
354       return 64;
355    default:
356       unreachable("Invalid reg mode");
357       return 0;
358    }
359 }
360 
361 static int
bits_for_mode_halved(midgard_reg_mode mode,bool half)362 bits_for_mode_halved(midgard_reg_mode mode, bool half)
363 {
364    unsigned bits = bits_for_mode(mode);
365 
366    if (half)
367       bits >>= 1;
368 
369    return bits;
370 }
371 
372 static void
print_vec_selectors_64(FILE * fp,unsigned swizzle,midgard_reg_mode reg_mode,midgard_src_expand_mode expand_mode,unsigned selector_offset,uint8_t mask)373 print_vec_selectors_64(FILE *fp, unsigned swizzle, midgard_reg_mode reg_mode,
374                        midgard_src_expand_mode expand_mode,
375                        unsigned selector_offset, uint8_t mask)
376 {
377    bool expands = INPUT_EXPANDS(expand_mode);
378 
379    unsigned comp_skip = expands ? 1 : 2;
380    unsigned mask_bit = 0;
381    for (unsigned i = selector_offset; i < 4; i += comp_skip, mask_bit += 4) {
382       if (!(mask & (1 << mask_bit)))
383          continue;
384 
385       unsigned a = (swizzle >> (i * 2)) & 3;
386 
387       if (INPUT_EXPANDS(expand_mode)) {
388          if (expand_mode == midgard_src_expand_high)
389             a += 2;
390 
391          fprintf(fp, "%c", components[a / 2]);
392          continue;
393       }
394 
395       unsigned b = (swizzle >> ((i + 1) * 2)) & 3;
396 
397       /* Normally we're adjacent, but if there's an issue,
398        * don't make it ambiguous */
399 
400       if (b == a + 1)
401          fprintf(fp, "%c", a >> 1 ? 'Y' : 'X');
402       else
403          fprintf(fp, "[%c%c]", components[a], components[b]);
404    }
405 }
406 
407 static void
print_vec_selectors(FILE * fp,unsigned swizzle,midgard_reg_mode reg_mode,unsigned selector_offset,uint8_t mask,unsigned * mask_offset)408 print_vec_selectors(FILE *fp, unsigned swizzle, midgard_reg_mode reg_mode,
409                     unsigned selector_offset, uint8_t mask,
410                     unsigned *mask_offset)
411 {
412    assert(reg_mode != midgard_reg_mode_64);
413 
414    unsigned mask_skip = MAX2(bits_for_mode(reg_mode) / 16, 1);
415 
416    bool is_vec16 = reg_mode == midgard_reg_mode_8;
417 
418    for (unsigned i = 0; i < 4; i++, *mask_offset += mask_skip) {
419       if (!(mask & (1 << *mask_offset)))
420          continue;
421 
422       unsigned c = (swizzle >> (i * 2)) & 3;
423 
424       /* Vec16 has two components per swizzle selector. */
425       if (is_vec16)
426          c *= 2;
427 
428       c += selector_offset;
429 
430       fprintf(fp, "%c", components[c]);
431       if (is_vec16)
432          fprintf(fp, "%c", components[c + 1]);
433    }
434 }
435 
436 static void
print_vec_swizzle(FILE * fp,unsigned swizzle,midgard_src_expand_mode expand,midgard_reg_mode mode,uint8_t mask)437 print_vec_swizzle(FILE *fp, unsigned swizzle, midgard_src_expand_mode expand,
438                   midgard_reg_mode mode, uint8_t mask)
439 {
440    unsigned bits = bits_for_mode_halved(mode, INPUT_EXPANDS(expand));
441 
442    /* Swizzle selectors are divided in two halves that are always
443     * mirrored, the only difference is the starting component offset.
444     * The number represents an offset into the components[] array. */
445    unsigned first_half = 0;
446    unsigned second_half = (128 / bits) / 2; /* only used for 8 and 16-bit */
447 
448    switch (expand) {
449    case midgard_src_passthrough:
450       if (swizzle == 0xE4)
451          return; /* identity swizzle */
452       break;
453 
454    case midgard_src_expand_low:
455       second_half /= 2;
456       break;
457 
458    case midgard_src_expand_high:
459       first_half = second_half;
460       second_half += second_half / 2;
461       break;
462 
463       /* The rest of the cases are only used for 8 and 16-bit */
464 
465    case midgard_src_rep_low:
466       second_half = 0;
467       break;
468 
469    case midgard_src_rep_high:
470       first_half = second_half;
471       break;
472 
473    case midgard_src_swap:
474       first_half = second_half;
475       second_half = 0;
476       break;
477 
478    case midgard_src_expand_low_swap:
479       first_half = second_half / 2;
480       second_half = 0;
481       break;
482 
483    case midgard_src_expand_high_swap:
484       first_half = second_half + second_half / 2;
485       break;
486 
487    default:
488       unreachable("Invalid expand mode");
489       break;
490    }
491 
492    fprintf(fp, ".");
493 
494    /* Vec2 are weird so we use a separate function to simplify things. */
495    if (mode == midgard_reg_mode_64) {
496       print_vec_selectors_64(fp, swizzle, mode, expand, first_half, mask);
497       return;
498    }
499 
500    unsigned mask_offs = 0;
501    print_vec_selectors(fp, swizzle, mode, first_half, mask, &mask_offs);
502    if (mode == midgard_reg_mode_8 || mode == midgard_reg_mode_16)
503       print_vec_selectors(fp, swizzle, mode, second_half, mask, &mask_offs);
504 }
505 
506 static void
print_scalar_constant(FILE * fp,unsigned src_binary,const midgard_constants * consts,midgard_scalar_alu * alu)507 print_scalar_constant(FILE *fp, unsigned src_binary,
508                       const midgard_constants *consts, midgard_scalar_alu *alu)
509 {
510    midgard_scalar_alu_src *src = (midgard_scalar_alu_src *)&src_binary;
511    assert(consts != NULL);
512 
513    fprintf(fp, "#");
514    mir_print_constant_component(
515       fp, consts, src->component,
516       src->full ? midgard_reg_mode_32 : midgard_reg_mode_16, false, src->mod,
517       alu->op);
518 }
519 
520 static void
print_vector_constants(FILE * fp,unsigned src_binary,const midgard_constants * consts,midgard_vector_alu * alu)521 print_vector_constants(FILE *fp, unsigned src_binary,
522                        const midgard_constants *consts, midgard_vector_alu *alu)
523 {
524    midgard_vector_alu_src *src = (midgard_vector_alu_src *)&src_binary;
525    bool expands = INPUT_EXPANDS(src->expand_mode);
526    unsigned bits = bits_for_mode_halved(alu->reg_mode, expands);
527    unsigned max_comp = (sizeof(*consts) * 8) / bits;
528    unsigned comp_mask, num_comp = 0;
529 
530    assert(consts);
531    assert(max_comp <= 16);
532 
533    comp_mask =
534       effective_writemask(alu->op, condense_writemask(alu->mask, bits));
535    num_comp = util_bitcount(comp_mask);
536 
537    if (num_comp > 1)
538       fprintf(fp, "<");
539    else
540       fprintf(fp, "#");
541 
542    bool first = true;
543 
544    for (unsigned i = 0; i < max_comp; ++i) {
545       if (!(comp_mask & (1 << i)))
546          continue;
547 
548       unsigned c = (src->swizzle >> (i * 2)) & 3;
549 
550       if (bits == 16 && !expands) {
551          bool upper = i >= 4;
552 
553          switch (src->expand_mode) {
554          case midgard_src_passthrough:
555             c += upper * 4;
556             break;
557          case midgard_src_rep_low:
558             break;
559          case midgard_src_rep_high:
560             c += 4;
561             break;
562          case midgard_src_swap:
563             c += !upper * 4;
564             break;
565          default:
566             unreachable("invalid expand mode");
567             break;
568          }
569       } else if (bits == 32 && !expands) {
570          /* Implicitly ok */
571       } else if (bits == 64 && !expands) {
572          /* Implicitly ok */
573       } else if (bits == 8 && !expands) {
574          bool upper = i >= 8;
575 
576          unsigned index = (i >> 1) & 3;
577          unsigned base = (src->swizzle >> (index * 2)) & 3;
578          c = base * 2;
579 
580          switch (src->expand_mode) {
581          case midgard_src_passthrough:
582             c += upper * 8;
583             break;
584          case midgard_src_rep_low:
585             break;
586          case midgard_src_rep_high:
587             c += 8;
588             break;
589          case midgard_src_swap:
590             c += !upper * 8;
591             break;
592          default:
593             unreachable("invalid expand mode");
594             break;
595          }
596 
597          /* We work on twos, actually */
598          if (i & 1)
599             c++;
600       }
601 
602       if (first)
603          first = false;
604       else
605          fprintf(fp, ", ");
606 
607       mir_print_constant_component(fp, consts, c, alu->reg_mode, expands,
608                                    src->mod, alu->op);
609    }
610 
611    if (num_comp > 1)
612       fprintf(fp, ">");
613 }
614 
615 static void
print_srcmod(FILE * fp,bool is_int,bool expands,unsigned mod,bool scalar)616 print_srcmod(FILE *fp, bool is_int, bool expands, unsigned mod, bool scalar)
617 {
618    /* Modifiers change meaning depending on the op's context */
619 
620    if (is_int) {
621       if (expands)
622          fprintf(fp, "%s", srcmod_names_int[mod]);
623    } else {
624       if (mod & MIDGARD_FLOAT_MOD_ABS)
625          fprintf(fp, ".abs");
626       if (mod & MIDGARD_FLOAT_MOD_NEG)
627          fprintf(fp, ".neg");
628       if (expands)
629          fprintf(fp, ".widen");
630    }
631 }
632 
633 static void
print_vector_src(disassemble_context * ctx,FILE * fp,unsigned src_binary,midgard_reg_mode mode,unsigned reg,midgard_shrink_mode shrink_mode,uint8_t src_mask,bool is_int,midgard_special_arg_mod arg_mod)634 print_vector_src(disassemble_context *ctx, FILE *fp, unsigned src_binary,
635                  midgard_reg_mode mode, unsigned reg,
636                  midgard_shrink_mode shrink_mode, uint8_t src_mask, bool is_int,
637                  midgard_special_arg_mod arg_mod)
638 {
639    midgard_vector_alu_src *src = (midgard_vector_alu_src *)&src_binary;
640 
641    validate_expand_mode(src->expand_mode, mode);
642 
643    print_alu_reg(ctx, fp, reg, false);
644 
645    print_vec_swizzle(fp, src->swizzle, src->expand_mode, mode, src_mask);
646 
647    fprintf(fp, "%s", argmod_names[arg_mod]);
648 
649    print_srcmod(fp, is_int, INPUT_EXPANDS(src->expand_mode), src->mod, false);
650 }
651 
652 static uint16_t
decode_vector_imm(unsigned src2_reg,unsigned imm)653 decode_vector_imm(unsigned src2_reg, unsigned imm)
654 {
655    uint16_t ret;
656    ret = src2_reg << 11;
657    ret |= (imm & 0x7) << 8;
658    ret |= (imm >> 3) & 0xFF;
659    return ret;
660 }
661 
662 static void
print_immediate(FILE * fp,uint16_t imm,bool is_instruction_int)663 print_immediate(FILE *fp, uint16_t imm, bool is_instruction_int)
664 {
665    if (is_instruction_int)
666       fprintf(fp, "#%u", imm);
667    else
668       fprintf(fp, "#%g", _mesa_half_to_float(imm));
669 }
670 
671 static void
update_dest(disassemble_context * ctx,unsigned reg)672 update_dest(disassemble_context *ctx, unsigned reg)
673 {
674    /* We should record writes as marking this as a work register. Store
675     * the max register in work_count; we'll add one at the end */
676 
677    if (reg < 16)
678       ctx->midg_ever_written |= (1 << reg);
679 }
680 
681 static void
print_dest(disassemble_context * ctx,FILE * fp,unsigned reg)682 print_dest(disassemble_context *ctx, FILE *fp, unsigned reg)
683 {
684    update_dest(ctx, reg);
685    print_alu_reg(ctx, fp, reg, true);
686 }
687 
688 /* For 16-bit+ masks, we read off from the 8-bit mask field. For 16-bit (vec8),
689  * it's just one bit per channel, easy peasy. For 32-bit (vec4), it's one bit
690  * per channel with one duplicate bit in the middle. For 64-bit (vec2), it's
691  * one-bit per channel with _3_ duplicate bits in the middle. Basically, just
692  * subdividing the 128-bit word in 16-bit increments. For 64-bit, we uppercase
693  * the mask to make it obvious what happened */
694 
695 static void
print_alu_mask(FILE * fp,uint8_t mask,unsigned bits,midgard_shrink_mode shrink_mode)696 print_alu_mask(FILE *fp, uint8_t mask, unsigned bits,
697                midgard_shrink_mode shrink_mode)
698 {
699    /* Skip 'complete' masks */
700 
701    if (shrink_mode == midgard_shrink_mode_none && mask == 0xFF)
702       return;
703 
704    fprintf(fp, ".");
705 
706    unsigned skip = MAX2(bits / 16, 1);
707    bool tripped = false;
708 
709    /* To apply an upper destination shrink_mode, we "shift" the alphabet.
710     * E.g. with an upper shrink_mode on 32-bit, instead of xyzw, print efgh.
711     * For upper 16-bit, instead of xyzwefgh, print ijklmnop */
712 
713    const char *alphabet = components;
714 
715    if (shrink_mode == midgard_shrink_mode_upper) {
716       assert(bits != 8);
717       alphabet += (128 / bits);
718    }
719 
720    for (unsigned i = 0; i < 8; i += skip) {
721       bool a = (mask & (1 << i)) != 0;
722 
723       for (unsigned j = 1; j < skip; ++j) {
724          bool dupe = (mask & (1 << (i + j))) != 0;
725          tripped |= (dupe != a);
726       }
727 
728       if (a) {
729          /* TODO: handle shrinking from 16-bit */
730          unsigned comp_idx = bits == 8 ? i * 2 : i;
731          char c = alphabet[comp_idx / skip];
732 
733          fprintf(fp, "%c", c);
734          if (bits == 8)
735             fprintf(fp, "%c", alphabet[comp_idx + 1]);
736       }
737    }
738 
739    if (tripped)
740       fprintf(fp, " /* %X */", mask);
741 }
742 
743 /* TODO: 16-bit mode */
744 static void
print_ldst_mask(FILE * fp,unsigned mask,unsigned swizzle)745 print_ldst_mask(FILE *fp, unsigned mask, unsigned swizzle)
746 {
747    fprintf(fp, ".");
748 
749    for (unsigned i = 0; i < 4; ++i) {
750       bool write = (mask & (1 << i)) != 0;
751       unsigned c = (swizzle >> (i * 2)) & 3;
752       /* We can't omit the swizzle here since many ldst ops have a
753        * combined swizzle/writemask, and it would be ambiguous to not
754        * print the masked-out components. */
755       fprintf(fp, "%c", write ? components[c] : '~');
756    }
757 }
758 
759 static void
print_tex_mask(FILE * fp,unsigned mask,bool upper)760 print_tex_mask(FILE *fp, unsigned mask, bool upper)
761 {
762    if (mask == 0xF) {
763       if (upper)
764          fprintf(fp, "'");
765 
766       return;
767    }
768 
769    fprintf(fp, ".");
770 
771    for (unsigned i = 0; i < 4; ++i) {
772       bool a = (mask & (1 << i)) != 0;
773       if (a)
774          fprintf(fp, "%c", components[i + (upper ? 4 : 0)]);
775    }
776 }
777 
778 static void
print_vector_field(disassemble_context * ctx,FILE * fp,const char * name,uint16_t * words,uint16_t reg_word,const midgard_constants * consts,unsigned tabs,bool verbose)779 print_vector_field(disassemble_context *ctx, FILE *fp, const char *name,
780                    uint16_t *words, uint16_t reg_word,
781                    const midgard_constants *consts, unsigned tabs, bool verbose)
782 {
783    midgard_reg_info *reg_info = (midgard_reg_info *)&reg_word;
784    midgard_vector_alu *alu_field = (midgard_vector_alu *)words;
785    midgard_reg_mode mode = alu_field->reg_mode;
786    midgard_alu_op op = alu_field->op;
787    unsigned shrink_mode = alu_field->shrink_mode;
788    bool is_int = midgard_is_integer_op(op);
789    bool is_int_out = midgard_is_integer_out_op(op);
790 
791    if (verbose)
792       fprintf(fp, "%s.", name);
793 
794    bool is_instruction_int = print_alu_opcode(fp, alu_field->op);
795 
796    /* Print lane width */
797    fprintf(fp, ".%c%d", is_int_out ? 'i' : 'f', bits_for_mode(mode));
798 
799    fprintf(fp, " ");
800 
801    /* Mask denoting status of 8-lanes */
802    uint8_t mask = alu_field->mask;
803 
804    /* First, print the destination */
805    print_dest(ctx, fp, reg_info->out_reg);
806 
807    if (shrink_mode != midgard_shrink_mode_none) {
808       bool shrinkable = (mode != midgard_reg_mode_8);
809       bool known = shrink_mode != 0x3; /* Unused value */
810 
811       if (!(shrinkable && known))
812          fprintf(fp, "/* do%u */ ", shrink_mode);
813    }
814 
815    /* Instructions like fdot4 do *not* replicate, ensure the
816     * mask is of only a single component */
817 
818    unsigned rep = GET_CHANNEL_COUNT(alu_opcode_props[op].props);
819 
820    if (rep) {
821       unsigned comp_mask = condense_writemask(mask, bits_for_mode(mode));
822       unsigned num_comp = util_bitcount(comp_mask);
823       if (num_comp != 1)
824          fprintf(fp, "/* err too many components */");
825    }
826    print_alu_mask(fp, mask, bits_for_mode(mode), shrink_mode);
827 
828    /* Print output modifiers */
829 
830    print_alu_outmod(fp, alu_field->outmod, is_int_out,
831                     shrink_mode != midgard_shrink_mode_none);
832 
833    /* Mask out unused components based on the writemask, but don't mask out
834     * components that are used for interlane instructions like fdot3. */
835    uint8_t src_mask =
836       rep ? expand_writemask(mask_of(rep),
837                              util_logbase2(128 / bits_for_mode(mode)))
838           : mask;
839 
840    fprintf(fp, ", ");
841 
842    if (reg_info->src1_reg == REGISTER_CONSTANT)
843       print_vector_constants(fp, alu_field->src1, consts, alu_field);
844    else {
845       midgard_special_arg_mod argmod = midgard_alu_special_arg_mod(op, 1);
846       print_vector_src(ctx, fp, alu_field->src1, mode, reg_info->src1_reg,
847                        shrink_mode, src_mask, is_int, argmod);
848    }
849 
850    fprintf(fp, ", ");
851 
852    if (reg_info->src2_imm) {
853       uint16_t imm =
854          decode_vector_imm(reg_info->src2_reg, alu_field->src2 >> 2);
855       print_immediate(fp, imm, is_instruction_int);
856    } else if (reg_info->src2_reg == REGISTER_CONSTANT) {
857       print_vector_constants(fp, alu_field->src2, consts, alu_field);
858    } else {
859       midgard_special_arg_mod argmod = midgard_alu_special_arg_mod(op, 2);
860       print_vector_src(ctx, fp, alu_field->src2, mode, reg_info->src2_reg,
861                        shrink_mode, src_mask, is_int, argmod);
862    }
863 
864    fprintf(fp, "\n");
865 }
866 
867 static void
print_scalar_src(disassemble_context * ctx,FILE * fp,bool is_int,unsigned src_binary,unsigned reg)868 print_scalar_src(disassemble_context *ctx, FILE *fp, bool is_int,
869                  unsigned src_binary, unsigned reg)
870 {
871    midgard_scalar_alu_src *src = (midgard_scalar_alu_src *)&src_binary;
872 
873    print_alu_reg(ctx, fp, reg, false);
874 
875    unsigned c = src->component;
876 
877    if (src->full) {
878       assert((c & 1) == 0);
879       c >>= 1;
880    }
881 
882    fprintf(fp, ".%c", components[c]);
883 
884    print_srcmod(fp, is_int, !src->full, src->mod, true);
885 }
886 
887 static uint16_t
decode_scalar_imm(unsigned src2_reg,unsigned imm)888 decode_scalar_imm(unsigned src2_reg, unsigned imm)
889 {
890    uint16_t ret;
891    ret = src2_reg << 11;
892    ret |= (imm & 3) << 9;
893    ret |= (imm & 4) << 6;
894    ret |= (imm & 0x38) << 2;
895    ret |= imm >> 6;
896    return ret;
897 }
898 
899 static void
print_scalar_field(disassemble_context * ctx,FILE * fp,const char * name,uint16_t * words,uint16_t reg_word,const midgard_constants * consts,unsigned tabs,bool verbose)900 print_scalar_field(disassemble_context *ctx, FILE *fp, const char *name,
901                    uint16_t *words, uint16_t reg_word,
902                    const midgard_constants *consts, unsigned tabs, bool verbose)
903 {
904    midgard_reg_info *reg_info = (midgard_reg_info *)&reg_word;
905    midgard_scalar_alu *alu_field = (midgard_scalar_alu *)words;
906    bool is_int = midgard_is_integer_op(alu_field->op);
907    bool is_int_out = midgard_is_integer_out_op(alu_field->op);
908    bool full = alu_field->output_full;
909 
910    if (alu_field->reserved)
911       fprintf(fp, "scalar ALU reserved bit set\n");
912 
913    if (verbose)
914       fprintf(fp, "%s.", name);
915 
916    bool is_instruction_int = print_alu_opcode(fp, alu_field->op);
917 
918    /* Print lane width, in this case the lane width is always 32-bit, but
919     * we print it anyway to make it consistent with the other instructions. */
920    fprintf(fp, ".%c32", is_int_out ? 'i' : 'f');
921 
922    fprintf(fp, " ");
923 
924    print_dest(ctx, fp, reg_info->out_reg);
925    unsigned c = alu_field->output_component;
926 
927    if (full) {
928       assert((c & 1) == 0);
929       c >>= 1;
930    }
931 
932    fprintf(fp, ".%c", components[c]);
933 
934    print_alu_outmod(fp, alu_field->outmod, is_int_out, !full);
935 
936    fprintf(fp, ", ");
937 
938    if (reg_info->src1_reg == REGISTER_CONSTANT)
939       print_scalar_constant(fp, alu_field->src1, consts, alu_field);
940    else
941       print_scalar_src(ctx, fp, is_int, alu_field->src1, reg_info->src1_reg);
942 
943    fprintf(fp, ", ");
944 
945    if (reg_info->src2_imm) {
946       uint16_t imm = decode_scalar_imm(reg_info->src2_reg, alu_field->src2);
947       print_immediate(fp, imm, is_instruction_int);
948    } else if (reg_info->src2_reg == REGISTER_CONSTANT) {
949       print_scalar_constant(fp, alu_field->src2, consts, alu_field);
950    } else
951       print_scalar_src(ctx, fp, is_int, alu_field->src2, reg_info->src2_reg);
952 
953    fprintf(fp, "\n");
954 }
955 
956 static void
print_branch_op(FILE * fp,unsigned op)957 print_branch_op(FILE *fp, unsigned op)
958 {
959    switch (op) {
960    case midgard_jmp_writeout_op_branch_uncond:
961       fprintf(fp, "uncond.");
962       break;
963 
964    case midgard_jmp_writeout_op_branch_cond:
965       fprintf(fp, "cond.");
966       break;
967 
968    case midgard_jmp_writeout_op_writeout:
969       fprintf(fp, "write.");
970       break;
971 
972    case midgard_jmp_writeout_op_tilebuffer_pending:
973       fprintf(fp, "tilebuffer.");
974       break;
975 
976    case midgard_jmp_writeout_op_discard:
977       fprintf(fp, "discard.");
978       break;
979 
980    default:
981       fprintf(fp, "unk%u.", op);
982       break;
983    }
984 }
985 
986 static void
print_branch_cond(FILE * fp,int cond)987 print_branch_cond(FILE *fp, int cond)
988 {
989    switch (cond) {
990    case midgard_condition_write0:
991       fprintf(fp, "write0");
992       break;
993 
994    case midgard_condition_false:
995       fprintf(fp, "false");
996       break;
997 
998    case midgard_condition_true:
999       fprintf(fp, "true");
1000       break;
1001 
1002    case midgard_condition_always:
1003       fprintf(fp, "always");
1004       break;
1005 
1006    default:
1007       fprintf(fp, "unk%X", cond);
1008       break;
1009    }
1010 }
1011 
1012 static const char *
function_call_mode(enum midgard_call_mode mode)1013 function_call_mode(enum midgard_call_mode mode)
1014 {
1015    switch (mode) {
1016    case midgard_call_mode_default:
1017       return "";
1018    case midgard_call_mode_call:
1019       return ".call";
1020    case midgard_call_mode_return:
1021       return ".return";
1022    default:
1023       return ".reserved";
1024    }
1025 }
1026 
1027 static bool
print_compact_branch_writeout_field(disassemble_context * ctx,FILE * fp,uint16_t word)1028 print_compact_branch_writeout_field(disassemble_context *ctx, FILE *fp,
1029                                     uint16_t word)
1030 {
1031    midgard_jmp_writeout_op op = word & 0x7;
1032 
1033    switch (op) {
1034    case midgard_jmp_writeout_op_branch_uncond: {
1035       midgard_branch_uncond br_uncond;
1036       memcpy((char *)&br_uncond, (char *)&word, sizeof(br_uncond));
1037       fprintf(fp, "br.uncond%s ", function_call_mode(br_uncond.call_mode));
1038 
1039       if (br_uncond.offset >= 0)
1040          fprintf(fp, "+");
1041 
1042       fprintf(fp, "%d -> %s", br_uncond.offset,
1043               midgard_tag_props[br_uncond.dest_tag].name);
1044       fprintf(fp, "\n");
1045 
1046       return br_uncond.offset >= 0;
1047    }
1048 
1049    case midgard_jmp_writeout_op_branch_cond:
1050    case midgard_jmp_writeout_op_writeout:
1051    case midgard_jmp_writeout_op_discard:
1052    default: {
1053       midgard_branch_cond br_cond;
1054       memcpy((char *)&br_cond, (char *)&word, sizeof(br_cond));
1055 
1056       fprintf(fp, "br.");
1057 
1058       print_branch_op(fp, br_cond.op);
1059       print_branch_cond(fp, br_cond.cond);
1060 
1061       fprintf(fp, " ");
1062 
1063       if (br_cond.offset >= 0)
1064          fprintf(fp, "+");
1065 
1066       fprintf(fp, "%d -> %s", br_cond.offset,
1067               midgard_tag_props[br_cond.dest_tag].name);
1068       fprintf(fp, "\n");
1069 
1070       return br_cond.offset >= 0;
1071    }
1072    }
1073 
1074    return false;
1075 }
1076 
1077 static bool
print_extended_branch_writeout_field(disassemble_context * ctx,FILE * fp,uint8_t * words,unsigned next)1078 print_extended_branch_writeout_field(disassemble_context *ctx, FILE *fp,
1079                                      uint8_t *words, unsigned next)
1080 {
1081    midgard_branch_extended br;
1082    memcpy((char *)&br, (char *)words, sizeof(br));
1083 
1084    fprintf(fp, "brx%s.", function_call_mode(br.call_mode));
1085 
1086    print_branch_op(fp, br.op);
1087 
1088    /* Condition codes are a LUT in the general case, but simply repeated 8 times
1089     * for single-channel conditions.. Check this. */
1090 
1091    bool single_channel = true;
1092 
1093    for (unsigned i = 0; i < 16; i += 2) {
1094       single_channel &= (((br.cond >> i) & 0x3) == (br.cond & 0x3));
1095    }
1096 
1097    if (single_channel)
1098       print_branch_cond(fp, br.cond & 0x3);
1099    else
1100       fprintf(fp, "lut%X", br.cond);
1101 
1102    fprintf(fp, " ");
1103 
1104    if (br.offset >= 0)
1105       fprintf(fp, "+");
1106 
1107    fprintf(fp, "%d -> %s\n", br.offset, midgard_tag_props[br.dest_tag].name);
1108 
1109    unsigned I = next + br.offset * 4;
1110 
1111    if (ctx->midg_tags[I] && ctx->midg_tags[I] != br.dest_tag) {
1112       fprintf(fp, "\t/* XXX TAG ERROR: jumping to %s but tagged %s \n",
1113               midgard_tag_props[br.dest_tag].name,
1114               midgard_tag_props[ctx->midg_tags[I]].name);
1115    }
1116 
1117    ctx->midg_tags[I] = br.dest_tag;
1118 
1119    return br.offset >= 0;
1120 }
1121 
1122 static unsigned
num_alu_fields_enabled(uint32_t control_word)1123 num_alu_fields_enabled(uint32_t control_word)
1124 {
1125    unsigned ret = 0;
1126 
1127    if ((control_word >> 17) & 1)
1128       ret++;
1129 
1130    if ((control_word >> 19) & 1)
1131       ret++;
1132 
1133    if ((control_word >> 21) & 1)
1134       ret++;
1135 
1136    if ((control_word >> 23) & 1)
1137       ret++;
1138 
1139    if ((control_word >> 25) & 1)
1140       ret++;
1141 
1142    return ret;
1143 }
1144 
1145 static bool
print_alu_word(disassemble_context * ctx,FILE * fp,const uint32_t * words,unsigned num_quad_words,unsigned tabs,unsigned next,bool verbose)1146 print_alu_word(disassemble_context *ctx, FILE *fp, const uint32_t *words,
1147                unsigned num_quad_words, unsigned tabs, unsigned next,
1148                bool verbose)
1149 {
1150    uint32_t control_word = words[0];
1151    uint16_t *beginning_ptr = (uint16_t *)(words + 1);
1152    unsigned num_fields = num_alu_fields_enabled(control_word);
1153    uint16_t *word_ptr = beginning_ptr + num_fields;
1154    unsigned num_words = 2 + num_fields;
1155    const midgard_constants *consts = NULL;
1156    bool branch_forward = false;
1157 
1158    if ((control_word >> 17) & 1)
1159       num_words += 3;
1160 
1161    if ((control_word >> 19) & 1)
1162       num_words += 2;
1163 
1164    if ((control_word >> 21) & 1)
1165       num_words += 3;
1166 
1167    if ((control_word >> 23) & 1)
1168       num_words += 2;
1169 
1170    if ((control_word >> 25) & 1)
1171       num_words += 3;
1172 
1173    if ((control_word >> 26) & 1)
1174       num_words += 1;
1175 
1176    if ((control_word >> 27) & 1)
1177       num_words += 3;
1178 
1179    if (num_quad_words > (num_words + 7) / 8) {
1180       assert(num_quad_words == (num_words + 15) / 8);
1181       // Assume that the extra quadword is constants
1182       consts = (midgard_constants *)(words + (4 * num_quad_words - 4));
1183    }
1184 
1185    if ((control_word >> 16) & 1)
1186       fprintf(fp, "unknown bit 16 enabled\n");
1187 
1188    if ((control_word >> 17) & 1) {
1189       print_vector_field(ctx, fp, "vmul", word_ptr, *beginning_ptr, consts,
1190                          tabs, verbose);
1191       beginning_ptr += 1;
1192       word_ptr += 3;
1193    }
1194 
1195    if ((control_word >> 18) & 1)
1196       fprintf(fp, "unknown bit 18 enabled\n");
1197 
1198    if ((control_word >> 19) & 1) {
1199       print_scalar_field(ctx, fp, "sadd", word_ptr, *beginning_ptr, consts,
1200                          tabs, verbose);
1201       beginning_ptr += 1;
1202       word_ptr += 2;
1203    }
1204 
1205    if ((control_word >> 20) & 1)
1206       fprintf(fp, "unknown bit 20 enabled\n");
1207 
1208    if ((control_word >> 21) & 1) {
1209       print_vector_field(ctx, fp, "vadd", word_ptr, *beginning_ptr, consts,
1210                          tabs, verbose);
1211       beginning_ptr += 1;
1212       word_ptr += 3;
1213    }
1214 
1215    if ((control_word >> 22) & 1)
1216       fprintf(fp, "unknown bit 22 enabled\n");
1217 
1218    if ((control_word >> 23) & 1) {
1219       print_scalar_field(ctx, fp, "smul", word_ptr, *beginning_ptr, consts,
1220                          tabs, verbose);
1221       beginning_ptr += 1;
1222       word_ptr += 2;
1223    }
1224 
1225    if ((control_word >> 24) & 1)
1226       fprintf(fp, "unknown bit 24 enabled\n");
1227 
1228    if ((control_word >> 25) & 1) {
1229       print_vector_field(ctx, fp, "lut", word_ptr, *beginning_ptr, consts, tabs,
1230                          verbose);
1231       word_ptr += 3;
1232    }
1233 
1234    if ((control_word >> 26) & 1) {
1235       branch_forward |= print_compact_branch_writeout_field(ctx, fp, *word_ptr);
1236       word_ptr += 1;
1237    }
1238 
1239    if ((control_word >> 27) & 1) {
1240       branch_forward |= print_extended_branch_writeout_field(
1241          ctx, fp, (uint8_t *)word_ptr, next);
1242       word_ptr += 3;
1243    }
1244 
1245    if (consts)
1246       fprintf(fp, "uconstants 0x%X, 0x%X, 0x%X, 0x%X\n", consts->u32[0],
1247               consts->u32[1], consts->u32[2], consts->u32[3]);
1248 
1249    return branch_forward;
1250 }
1251 
1252 /* TODO: how can we use this now that we know that these params can't be known
1253  * before run time in every single case? Maybe just use it in the cases we can? */
1254 UNUSED static void
print_varying_parameters(FILE * fp,midgard_load_store_word * word)1255 print_varying_parameters(FILE *fp, midgard_load_store_word *word)
1256 {
1257    midgard_varying_params p = midgard_unpack_varying_params(*word);
1258 
1259    /* If a varying, there are qualifiers */
1260    if (p.flat_shading)
1261       fprintf(fp, ".flat");
1262 
1263    if (p.perspective_correction)
1264       fprintf(fp, ".correction");
1265 
1266    if (p.centroid_mapping)
1267       fprintf(fp, ".centroid");
1268 
1269    if (p.interpolate_sample)
1270       fprintf(fp, ".sample");
1271 
1272    switch (p.modifier) {
1273    case midgard_varying_mod_perspective_y:
1274       fprintf(fp, ".perspectivey");
1275       break;
1276    case midgard_varying_mod_perspective_z:
1277       fprintf(fp, ".perspectivez");
1278       break;
1279    case midgard_varying_mod_perspective_w:
1280       fprintf(fp, ".perspectivew");
1281       break;
1282    default:
1283       unreachable("invalid varying modifier");
1284       break;
1285    }
1286 }
1287 
1288 /* Helper to print integer well-formatted, but only when non-zero. */
1289 static void
midgard_print_sint(FILE * fp,int n)1290 midgard_print_sint(FILE *fp, int n)
1291 {
1292    if (n > 0)
1293       fprintf(fp, " + 0x%X", n);
1294    else if (n < 0)
1295       fprintf(fp, " - 0x%X", -n);
1296 }
1297 
1298 static void
print_load_store_instr(disassemble_context * ctx,FILE * fp,uint64_t data,bool verbose)1299 print_load_store_instr(disassemble_context *ctx, FILE *fp, uint64_t data,
1300                        bool verbose)
1301 {
1302    midgard_load_store_word *word = (midgard_load_store_word *)&data;
1303 
1304    print_ld_st_opcode(fp, word->op);
1305 
1306    if (word->op == midgard_op_trap) {
1307       fprintf(fp, " 0x%X\n", word->signed_offset);
1308       return;
1309    }
1310 
1311    /* Print opcode modifiers */
1312 
1313    if (OP_USES_ATTRIB(word->op)) {
1314       /* Print non-default attribute tables */
1315       bool default_secondary = (word->op == midgard_op_st_vary_32) ||
1316                                (word->op == midgard_op_st_vary_16) ||
1317                                (word->op == midgard_op_st_vary_32u) ||
1318                                (word->op == midgard_op_st_vary_32i) ||
1319                                (word->op == midgard_op_ld_vary_32) ||
1320                                (word->op == midgard_op_ld_vary_16) ||
1321                                (word->op == midgard_op_ld_vary_32u) ||
1322                                (word->op == midgard_op_ld_vary_32i);
1323 
1324       bool default_primary = (word->op == midgard_op_ld_attr_32) ||
1325                              (word->op == midgard_op_ld_attr_16) ||
1326                              (word->op == midgard_op_ld_attr_32u) ||
1327                              (word->op == midgard_op_ld_attr_32i);
1328 
1329       bool has_default = (default_secondary || default_primary);
1330       bool auto32 = (word->index_format >> 0) & 1;
1331       bool is_secondary = (word->index_format >> 1) & 1;
1332 
1333       if (auto32)
1334          fprintf(fp, ".a32");
1335 
1336       if (has_default && (is_secondary != default_secondary))
1337          fprintf(fp, ".%s", is_secondary ? "secondary" : "primary");
1338    } else if (word->op == midgard_op_ld_cubemap_coords ||
1339               OP_IS_PROJECTION(word->op))
1340       fprintf(fp, ".%s", word->bitsize_toggle ? "f32" : "f16");
1341 
1342    fprintf(fp, " ");
1343 
1344    /* src/dest register */
1345 
1346    if (!OP_IS_STORE(word->op)) {
1347       print_ldst_write_reg(fp, word->reg);
1348 
1349       /* Some opcodes don't have a swizzable src register, and
1350        * instead the swizzle is applied before the result is written
1351        * to the dest reg. For these ops, we combine the writemask
1352        * with the swizzle to display them in the disasm compactly. */
1353       unsigned swizzle = word->swizzle;
1354       if ((OP_IS_REG2REG_LDST(word->op) && word->op != midgard_op_lea &&
1355            word->op != midgard_op_lea_image) ||
1356           OP_IS_ATOMIC(word->op))
1357          swizzle = 0xE4;
1358       print_ldst_mask(fp, word->mask, swizzle);
1359    } else {
1360       uint8_t mask = (word->mask & 0x1) | ((word->mask & 0x2) << 1) |
1361                      ((word->mask & 0x4) << 2) | ((word->mask & 0x8) << 3);
1362       mask |= mask << 1;
1363       print_ldst_read_reg(fp, word->reg);
1364       print_vec_swizzle(fp, word->swizzle, midgard_src_passthrough,
1365                         midgard_reg_mode_32, mask);
1366    }
1367 
1368    /* ld_ubo args */
1369    if (OP_IS_UBO_READ(word->op)) {
1370       if (word->signed_offset & 1) { /* buffer index imm */
1371          unsigned imm = midgard_unpack_ubo_index_imm(*word);
1372          fprintf(fp, ", %u", imm);
1373       } else { /* buffer index from reg */
1374          fprintf(fp, ", ");
1375          print_ldst_read_reg(fp, word->arg_reg);
1376          fprintf(fp, ".%c", components[word->arg_comp]);
1377       }
1378 
1379       fprintf(fp, ", ");
1380       print_ldst_read_reg(fp, word->index_reg);
1381       fprintf(fp, ".%c", components[word->index_comp]);
1382       if (word->index_shift)
1383          fprintf(fp, " << %u", word->index_shift);
1384       midgard_print_sint(fp, UNPACK_LDST_UBO_OFS(word->signed_offset));
1385    }
1386 
1387    /* mem addr expression */
1388    if (OP_HAS_ADDRESS(word->op)) {
1389       fprintf(fp, ", ");
1390       bool first = true;
1391 
1392       /* Skip printing zero */
1393       if (word->arg_reg != 7 || verbose) {
1394          print_ldst_read_reg(fp, word->arg_reg);
1395          fprintf(fp, ".u%d.%c", word->bitsize_toggle ? 64 : 32,
1396                  components[word->arg_comp]);
1397          first = false;
1398       }
1399 
1400       if ((word->op < midgard_op_atomic_cmpxchg ||
1401            word->op > midgard_op_atomic_cmpxchg64_be) &&
1402           word->index_reg != 0x7) {
1403          if (!first)
1404             fprintf(fp, " + ");
1405 
1406          print_ldst_read_reg(fp, word->index_reg);
1407          fprintf(fp, "%s.%c", index_format_names[word->index_format],
1408                  components[word->index_comp]);
1409          if (word->index_shift)
1410             fprintf(fp, " << %u", word->index_shift);
1411       }
1412 
1413       midgard_print_sint(fp, word->signed_offset);
1414    }
1415 
1416    /* src reg for reg2reg ldst opcodes */
1417    if (OP_IS_REG2REG_LDST(word->op)) {
1418       fprintf(fp, ", ");
1419       print_ldst_read_reg(fp, word->arg_reg);
1420       print_vec_swizzle(fp, word->swizzle, midgard_src_passthrough,
1421                         midgard_reg_mode_32, 0xFF);
1422    }
1423 
1424    /* atomic ops encode the source arg where the ldst swizzle would be. */
1425    if (OP_IS_ATOMIC(word->op)) {
1426       unsigned src = (word->swizzle >> 2) & 0x7;
1427       unsigned src_comp = word->swizzle & 0x3;
1428       fprintf(fp, ", ");
1429       print_ldst_read_reg(fp, src);
1430       fprintf(fp, ".%c", components[src_comp]);
1431    }
1432 
1433    /* CMPXCHG encodes the extra comparison arg where the index reg would be. */
1434    if (word->op >= midgard_op_atomic_cmpxchg &&
1435        word->op <= midgard_op_atomic_cmpxchg64_be) {
1436       fprintf(fp, ", ");
1437       print_ldst_read_reg(fp, word->index_reg);
1438       fprintf(fp, ".%c", components[word->index_comp]);
1439    }
1440 
1441    /* index reg for attr/vary/images, selector for ld/st_special */
1442    if (OP_IS_SPECIAL(word->op) || OP_USES_ATTRIB(word->op)) {
1443       fprintf(fp, ", ");
1444       print_ldst_read_reg(fp, word->index_reg);
1445       fprintf(fp, ".%c", components[word->index_comp]);
1446       if (word->index_shift)
1447          fprintf(fp, " << %u", word->index_shift);
1448       midgard_print_sint(fp, UNPACK_LDST_ATTRIB_OFS(word->signed_offset));
1449    }
1450 
1451    /* vertex reg for attrib/varying ops, coord reg for image ops */
1452    if (OP_USES_ATTRIB(word->op)) {
1453       fprintf(fp, ", ");
1454       print_ldst_read_reg(fp, word->arg_reg);
1455 
1456       if (OP_IS_IMAGE(word->op))
1457          fprintf(fp, ".u%d", word->bitsize_toggle ? 64 : 32);
1458 
1459       fprintf(fp, ".%c", components[word->arg_comp]);
1460 
1461       if (word->bitsize_toggle && !OP_IS_IMAGE(word->op))
1462          midgard_print_sint(fp, UNPACK_LDST_VERTEX_OFS(word->signed_offset));
1463    }
1464 
1465    /* TODO: properly decode format specifier for PACK/UNPACK ops */
1466    if (OP_IS_PACK_COLOUR(word->op) || OP_IS_UNPACK_COLOUR(word->op)) {
1467       fprintf(fp, ", ");
1468       unsigned format_specifier =
1469          (word->signed_offset << 4) | word->index_shift;
1470       fprintf(fp, "0x%X", format_specifier);
1471    }
1472 
1473    fprintf(fp, "\n");
1474 
1475    /* Debugging stuff */
1476 
1477    if (!OP_IS_STORE(word->op))
1478       update_dest(ctx, word->reg);
1479 }
1480 
1481 static void
print_load_store_word(disassemble_context * ctx,FILE * fp,const uint32_t * word,bool verbose)1482 print_load_store_word(disassemble_context *ctx, FILE *fp, const uint32_t *word,
1483                       bool verbose)
1484 {
1485    midgard_load_store *load_store = (midgard_load_store *)word;
1486 
1487    if (load_store->word1 != 3) {
1488       print_load_store_instr(ctx, fp, load_store->word1, verbose);
1489    }
1490 
1491    if (load_store->word2 != 3) {
1492       print_load_store_instr(ctx, fp, load_store->word2, verbose);
1493    }
1494 }
1495 
1496 static void
print_texture_reg_select(FILE * fp,uint8_t u,unsigned base)1497 print_texture_reg_select(FILE *fp, uint8_t u, unsigned base)
1498 {
1499    midgard_tex_register_select sel;
1500    memcpy(&sel, &u, sizeof(u));
1501 
1502    print_tex_reg(fp, base + sel.select, false);
1503 
1504    unsigned component = sel.component;
1505 
1506    /* Use the upper half in half-reg mode */
1507    if (sel.upper) {
1508       assert(!sel.full);
1509       component += 4;
1510    }
1511 
1512    fprintf(fp, ".%c.%d", components[component], sel.full ? 32 : 16);
1513 
1514    assert(sel.zero == 0);
1515 }
1516 
1517 static void
print_texture_format(FILE * fp,int format)1518 print_texture_format(FILE *fp, int format)
1519 {
1520    /* Act like a modifier */
1521    fprintf(fp, ".");
1522 
1523    switch (format) {
1524       DEFINE_CASE(1, "1d");
1525       DEFINE_CASE(2, "2d");
1526       DEFINE_CASE(3, "3d");
1527       DEFINE_CASE(0, "cube");
1528 
1529    default:
1530       unreachable("Bad format");
1531    }
1532 }
1533 
1534 static void
print_texture_op(FILE * fp,unsigned op)1535 print_texture_op(FILE *fp, unsigned op)
1536 {
1537    if (tex_opcode_props[op].name)
1538       fprintf(fp, "%s", tex_opcode_props[op].name);
1539    else
1540       fprintf(fp, "tex_op_%02X", op);
1541 }
1542 
1543 static bool
texture_op_takes_bias(unsigned op)1544 texture_op_takes_bias(unsigned op)
1545 {
1546    return op == midgard_tex_op_normal;
1547 }
1548 
1549 static char
sampler_type_name(enum mali_sampler_type t)1550 sampler_type_name(enum mali_sampler_type t)
1551 {
1552    switch (t) {
1553    case MALI_SAMPLER_FLOAT:
1554       return 'f';
1555    case MALI_SAMPLER_UNSIGNED:
1556       return 'u';
1557    case MALI_SAMPLER_SIGNED:
1558       return 'i';
1559    default:
1560       return '?';
1561    }
1562 }
1563 
1564 static void
print_texture_barrier(FILE * fp,const uint32_t * word)1565 print_texture_barrier(FILE *fp, const uint32_t *word)
1566 {
1567    midgard_texture_barrier_word *barrier = (midgard_texture_barrier_word *)word;
1568 
1569    if (barrier->type != TAG_TEXTURE_4_BARRIER)
1570       fprintf(fp, "/* barrier tag %X != tex/bar */ ", barrier->type);
1571 
1572    if (!barrier->cont)
1573       fprintf(fp, "/* cont missing? */");
1574 
1575    if (!barrier->last)
1576       fprintf(fp, "/* last missing? */");
1577 
1578    if (barrier->zero1)
1579       fprintf(fp, "/* zero1 = 0x%X */ ", barrier->zero1);
1580 
1581    if (barrier->zero2)
1582       fprintf(fp, "/* zero2 = 0x%X */ ", barrier->zero2);
1583 
1584    if (barrier->zero3)
1585       fprintf(fp, "/* zero3 = 0x%X */ ", barrier->zero3);
1586 
1587    if (barrier->zero4)
1588       fprintf(fp, "/* zero4 = 0x%X */ ", barrier->zero4);
1589 
1590    if (barrier->zero5)
1591       fprintf(fp, "/* zero4 = 0x%" PRIx64 " */ ", barrier->zero5);
1592 
1593    if (barrier->out_of_order)
1594       fprintf(fp, ".ooo%u", barrier->out_of_order);
1595 
1596    fprintf(fp, "\n");
1597 }
1598 
1599 #undef DEFINE_CASE
1600 
1601 static const char *
texture_mode(enum mali_texture_mode mode)1602 texture_mode(enum mali_texture_mode mode)
1603 {
1604    switch (mode) {
1605    case TEXTURE_NORMAL:
1606       return "";
1607    case TEXTURE_SHADOW:
1608       return ".shadow";
1609    case TEXTURE_GATHER_SHADOW:
1610       return ".gather.shadow";
1611    case TEXTURE_GATHER_X:
1612       return ".gatherX";
1613    case TEXTURE_GATHER_Y:
1614       return ".gatherY";
1615    case TEXTURE_GATHER_Z:
1616       return ".gatherZ";
1617    case TEXTURE_GATHER_W:
1618       return ".gatherW";
1619    default:
1620       return "unk";
1621    }
1622 }
1623 
1624 static const char *
derivative_mode(enum mali_derivative_mode mode)1625 derivative_mode(enum mali_derivative_mode mode)
1626 {
1627    switch (mode) {
1628    case TEXTURE_DFDX:
1629       return ".x";
1630    case TEXTURE_DFDY:
1631       return ".y";
1632    default:
1633       return "unk";
1634    }
1635 }
1636 
1637 static const char *
partial_exection_mode(enum midgard_partial_execution mode)1638 partial_exection_mode(enum midgard_partial_execution mode)
1639 {
1640    switch (mode) {
1641    case MIDGARD_PARTIAL_EXECUTION_NONE:
1642       return "";
1643    case MIDGARD_PARTIAL_EXECUTION_SKIP:
1644       return ".skip";
1645    case MIDGARD_PARTIAL_EXECUTION_KILL:
1646       return ".kill";
1647    default:
1648       return ".reserved";
1649    }
1650 }
1651 
1652 static void
print_texture_word(disassemble_context * ctx,FILE * fp,const uint32_t * word,unsigned tabs,unsigned in_reg_base,unsigned out_reg_base)1653 print_texture_word(disassemble_context *ctx, FILE *fp, const uint32_t *word,
1654                    unsigned tabs, unsigned in_reg_base, unsigned out_reg_base)
1655 {
1656    midgard_texture_word *texture = (midgard_texture_word *)word;
1657    validate_sampler_type(texture->op, texture->sampler_type);
1658 
1659    /* Broad category of texture operation in question */
1660    print_texture_op(fp, texture->op);
1661 
1662    /* Barriers use a dramatically different code path */
1663    if (texture->op == midgard_tex_op_barrier) {
1664       print_texture_barrier(fp, word);
1665       return;
1666    } else if (texture->type == TAG_TEXTURE_4_BARRIER)
1667       fprintf(fp, "/* nonbarrier had tex/bar tag */ ");
1668    else if (texture->type == TAG_TEXTURE_4_VTX)
1669       fprintf(fp, ".vtx");
1670 
1671    if (texture->op == midgard_tex_op_derivative)
1672       fprintf(fp, "%s", derivative_mode(texture->mode));
1673    else
1674       fprintf(fp, "%s", texture_mode(texture->mode));
1675 
1676    /* Specific format in question */
1677    print_texture_format(fp, texture->format);
1678 
1679    /* Instruction "modifiers" parallel the ALU instructions. */
1680    fputs(partial_exection_mode(texture->exec), fp);
1681 
1682    if (texture->out_of_order)
1683       fprintf(fp, ".ooo%u", texture->out_of_order);
1684 
1685    fprintf(fp, " ");
1686    print_tex_reg(fp, out_reg_base + texture->out_reg_select, true);
1687    print_tex_mask(fp, texture->mask, texture->out_upper);
1688    fprintf(fp, ".%c%d", texture->sampler_type == MALI_SAMPLER_FLOAT ? 'f' : 'i',
1689            texture->out_full ? 32 : 16);
1690    assert(!(texture->out_full && texture->out_upper));
1691 
1692    /* Output modifiers are only valid for float texture operations */
1693    if (texture->sampler_type == MALI_SAMPLER_FLOAT)
1694       mir_print_outmod(fp, texture->outmod, false);
1695 
1696    fprintf(fp, ", ");
1697 
1698    /* Depending on whether we read from textures directly or indirectly,
1699     * we may be able to update our analysis */
1700 
1701    if (texture->texture_register) {
1702       fprintf(fp, "texture[");
1703       print_texture_reg_select(fp, texture->texture_handle, in_reg_base);
1704       fprintf(fp, "], ");
1705    } else {
1706       fprintf(fp, "texture%u, ", texture->texture_handle);
1707    }
1708 
1709    /* Print the type, GL style */
1710    fprintf(fp, "%csampler", sampler_type_name(texture->sampler_type));
1711 
1712    if (texture->sampler_register) {
1713       fprintf(fp, "[");
1714       print_texture_reg_select(fp, texture->sampler_handle, in_reg_base);
1715       fprintf(fp, "]");
1716    } else {
1717       fprintf(fp, "%u", texture->sampler_handle);
1718    }
1719 
1720    print_vec_swizzle(fp, texture->swizzle, midgard_src_passthrough,
1721                      midgard_reg_mode_32, 0xFF);
1722 
1723    fprintf(fp, ", ");
1724 
1725    midgard_src_expand_mode exp =
1726       texture->in_reg_upper ? midgard_src_expand_high : midgard_src_passthrough;
1727    print_tex_reg(fp, in_reg_base + texture->in_reg_select, false);
1728    print_vec_swizzle(fp, texture->in_reg_swizzle, exp, midgard_reg_mode_32,
1729                      0xFF);
1730    fprintf(fp, ".%d", texture->in_reg_full ? 32 : 16);
1731    assert(!(texture->in_reg_full && texture->in_reg_upper));
1732 
1733    /* There is *always* an offset attached. Of
1734     * course, that offset is just immediate #0 for a
1735     * GLES call that doesn't take an offset. If there
1736     * is a non-negative non-zero offset, this is
1737     * specified in immediate offset mode, with the
1738     * values in the offset_* fields as immediates. If
1739     * this is a negative offset, we instead switch to
1740     * a register offset mode, where the offset_*
1741     * fields become register triplets */
1742 
1743    if (texture->offset_register) {
1744       fprintf(fp, " + ");
1745 
1746       bool full = texture->offset & 1;
1747       bool select = texture->offset & 2;
1748       bool upper = texture->offset & 4;
1749       unsigned swizzle = texture->offset >> 3;
1750       midgard_src_expand_mode exp =
1751          upper ? midgard_src_expand_high : midgard_src_passthrough;
1752 
1753       print_tex_reg(fp, in_reg_base + select, false);
1754       print_vec_swizzle(fp, swizzle, exp, midgard_reg_mode_32, 0xFF);
1755       fprintf(fp, ".%d", full ? 32 : 16);
1756       assert(!(texture->out_full && texture->out_upper));
1757 
1758       fprintf(fp, ", ");
1759    } else if (texture->offset) {
1760       /* Only select ops allow negative immediate offsets, verify */
1761 
1762       signed offset_x = (texture->offset & 0xF);
1763       signed offset_y = ((texture->offset >> 4) & 0xF);
1764       signed offset_z = ((texture->offset >> 8) & 0xF);
1765 
1766       bool neg_x = offset_x < 0;
1767       bool neg_y = offset_y < 0;
1768       bool neg_z = offset_z < 0;
1769       bool any_neg = neg_x || neg_y || neg_z;
1770 
1771       if (any_neg && texture->op != midgard_tex_op_fetch)
1772          fprintf(fp, "/* invalid negative */ ");
1773 
1774       /* Regardless, just print the immediate offset */
1775 
1776       fprintf(fp, " + <%d, %d, %d>, ", offset_x, offset_y, offset_z);
1777    } else {
1778       fprintf(fp, ", ");
1779    }
1780 
1781    char lod_operand = texture_op_takes_bias(texture->op) ? '+' : '=';
1782 
1783    if (texture->lod_register) {
1784       fprintf(fp, "lod %c ", lod_operand);
1785       print_texture_reg_select(fp, texture->bias, in_reg_base);
1786       fprintf(fp, ", ");
1787 
1788       if (texture->bias_int)
1789          fprintf(fp, " /* bias_int = 0x%X */", texture->bias_int);
1790    } else if (texture->op == midgard_tex_op_fetch) {
1791       /* For texel fetch, the int LOD is in the fractional place and
1792        * there is no fraction. We *always* have an explicit LOD, even
1793        * if it's zero. */
1794 
1795       if (texture->bias_int)
1796          fprintf(fp, " /* bias_int = 0x%X */ ", texture->bias_int);
1797 
1798       fprintf(fp, "lod = %u, ", texture->bias);
1799    } else if (texture->bias || texture->bias_int) {
1800       signed bias_int = texture->bias_int;
1801       float bias_frac = texture->bias / 256.0f;
1802       float bias = bias_int + bias_frac;
1803 
1804       bool is_bias = texture_op_takes_bias(texture->op);
1805       char sign = (bias >= 0.0) ? '+' : '-';
1806       char operand = is_bias ? sign : '=';
1807 
1808       fprintf(fp, "lod %c %f, ", operand, fabsf(bias));
1809    }
1810 
1811    fprintf(fp, "\n");
1812 
1813    /* While not zero in general, for these simple instructions the
1814     * following unknowns are zero, so we don't include them */
1815 
1816    if (texture->unknown4 || texture->unknown8) {
1817       fprintf(fp, "// unknown4 = 0x%x\n", texture->unknown4);
1818       fprintf(fp, "// unknown8 = 0x%x\n", texture->unknown8);
1819    }
1820 }
1821 
1822 void
disassemble_midgard(FILE * fp,const void * code,size_t size,unsigned gpu_id,bool verbose)1823 disassemble_midgard(FILE *fp, const void *code, size_t size, unsigned gpu_id,
1824                     bool verbose)
1825 {
1826    const uint32_t *words = (const uint32_t *)code;
1827    unsigned num_words = size / 4;
1828    int tabs = 0;
1829 
1830    bool branch_forward = false;
1831 
1832    int last_next_tag = -1;
1833 
1834    unsigned i = 0;
1835 
1836    disassemble_context ctx = {
1837       .midg_tags = calloc(sizeof(ctx.midg_tags[0]), num_words),
1838       .midg_ever_written = 0,
1839    };
1840 
1841    while (i < num_words) {
1842       unsigned tag = words[i] & 0xF;
1843       unsigned next_tag = (words[i] >> 4) & 0xF;
1844       unsigned num_quad_words = midgard_tag_props[tag].size;
1845 
1846       if (ctx.midg_tags[i] && ctx.midg_tags[i] != tag) {
1847          fprintf(fp, "\t/* XXX: TAG ERROR branch, got %s expected %s */\n",
1848                  midgard_tag_props[tag].name,
1849                  midgard_tag_props[ctx.midg_tags[i]].name);
1850       }
1851 
1852       ctx.midg_tags[i] = tag;
1853 
1854       /* Check the tag. The idea is to ensure that next_tag is
1855        * *always* recoverable from the disassembly, such that we may
1856        * safely omit printing next_tag. To show this, we first
1857        * consider that next tags are semantically off-byone -- we end
1858        * up parsing tag n during step n+1. So, we ensure after we're
1859        * done disassembling the next tag of the final bundle is BREAK
1860        * and warn otherwise. We also ensure that the next tag is
1861        * never INVALID. Beyond that, since the last tag is checked
1862        * outside the loop, we can check one tag prior. If equal to
1863        * the current tag (which is unique), we're done. Otherwise, we
1864        * print if that tag was > TAG_BREAK, which implies the tag was
1865        * not TAG_BREAK or TAG_INVALID. But we already checked for
1866        * TAG_INVALID, so it's just if the last tag was TAG_BREAK that
1867        * we're silent. So we throw in a print for break-next on at
1868        * the end of the bundle (if it's not the final bundle, which
1869        * we already check for above), disambiguating this case as
1870        * well.  Hence in all cases we are unambiguous, QED. */
1871 
1872       if (next_tag == TAG_INVALID)
1873          fprintf(fp, "\t/* XXX: invalid next tag */\n");
1874 
1875       if (last_next_tag > TAG_BREAK && last_next_tag != tag) {
1876          fprintf(fp, "\t/* XXX: TAG ERROR sequence, got %s expexted %s */\n",
1877                  midgard_tag_props[tag].name,
1878                  midgard_tag_props[last_next_tag].name);
1879       }
1880 
1881       last_next_tag = next_tag;
1882 
1883       /* Tags are unique in the following way:
1884        *
1885        * INVALID, BREAK, UNKNOWN_*: verbosely printed
1886        * TEXTURE_4_BARRIER: verified by barrier/!barrier op
1887        * TEXTURE_4_VTX: .vtx tag printed
1888        * TEXTURE_4: tetxure lack of barriers or .vtx
1889        * TAG_LOAD_STORE_4: only load/store
1890        * TAG_ALU_4/8/12/16: by number of instructions/constants
1891        * TAG_ALU_4_8/12/16_WRITEOUT: ^^ with .writeout tag
1892        */
1893 
1894       switch (tag) {
1895       case TAG_TEXTURE_4_VTX ... TAG_TEXTURE_4_BARRIER: {
1896          bool interpipe_aliasing =
1897             midgard_get_quirks(gpu_id) & MIDGARD_INTERPIPE_REG_ALIASING;
1898 
1899          print_texture_word(
1900             &ctx, fp, &words[i], tabs, interpipe_aliasing ? 0 : REG_TEX_BASE,
1901             interpipe_aliasing ? REGISTER_LDST_BASE : REG_TEX_BASE);
1902          break;
1903       }
1904 
1905       case TAG_LOAD_STORE_4:
1906          print_load_store_word(&ctx, fp, &words[i], verbose);
1907          break;
1908 
1909       case TAG_ALU_4 ... TAG_ALU_16_WRITEOUT:
1910          branch_forward = print_alu_word(&ctx, fp, &words[i], num_quad_words,
1911                                          tabs, i + 4 * num_quad_words, verbose);
1912 
1913          /* TODO: infer/verify me */
1914          if (tag >= TAG_ALU_4_WRITEOUT)
1915             fprintf(fp, "writeout\n");
1916 
1917          break;
1918 
1919       default:
1920          fprintf(fp, "Unknown word type %u:\n", words[i] & 0xF);
1921          num_quad_words = 1;
1922          print_quad_word(fp, &words[i], tabs);
1923          fprintf(fp, "\n");
1924          break;
1925       }
1926 
1927       /* Include a synthetic "break" instruction at the end of the
1928        * bundle to signify that if, absent a branch, the shader
1929        * execution will stop here. Stop disassembly at such a break
1930        * based on a heuristic */
1931 
1932       if (next_tag == TAG_BREAK) {
1933          if (branch_forward) {
1934             fprintf(fp, "break\n");
1935          } else {
1936             fprintf(fp, "\n");
1937             break;
1938          }
1939       }
1940 
1941       fprintf(fp, "\n");
1942 
1943       i += 4 * num_quad_words;
1944    }
1945 
1946    if (last_next_tag != TAG_BREAK) {
1947       fprintf(fp, "/* XXX: shader ended with tag %s */\n",
1948               midgard_tag_props[last_next_tag].name);
1949    }
1950 
1951    free(ctx.midg_tags);
1952 }
1953