2 * Copyright (C) 2018-2019 Alyssa Rosenzweig <alyssa@rosenzweig.io>
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:
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
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
24 #include <sys/types.h>
33 #include "main/mtypes.h"
34 #include "compiler/glsl/glsl_to_nir.h"
35 #include "compiler/nir_types.h"
36 #include "main/imports.h"
37 #include "compiler/nir/nir_builder.h"
38 #include "util/half_float.h"
39 #include "util/u_debug.h"
40 #include "util/u_dynarray.h"
41 #include "util/list.h"
42 #include "main/mtypes.h"
45 #include "midgard_nir.h"
46 #include "midgard_compile.h"
47 #include "midgard_ops.h"
51 #include "disassemble.h"
53 static const struct debug_named_value debug_options
[] = {
54 {"msgs", MIDGARD_DBG_MSGS
, "Print debug messages"},
55 {"shaders", MIDGARD_DBG_SHADERS
, "Dump shaders in NIR and MIR"},
59 DEBUG_GET_ONCE_FLAGS_OPTION(midgard_debug
, "MIDGARD_MESA_DEBUG", debug_options
, 0)
61 int midgard_debug
= 0;
63 #define DBG(fmt, ...) \
64 do { if (midgard_debug & MIDGARD_DBG_MSGS) \
65 fprintf(stderr, "%s:%d: "fmt, \
66 __FUNCTION__, __LINE__, ##__VA_ARGS__); } while (0)
69 midgard_is_branch_unit(unsigned unit
)
71 return (unit
== ALU_ENAB_BRANCH
) || (unit
== ALU_ENAB_BR_COMPACT
);
75 midgard_block_add_successor(midgard_block
*block
, midgard_block
*successor
)
77 block
->successors
[block
->nr_successors
++] = successor
;
78 assert(block
->nr_successors
<= ARRAY_SIZE(block
->successors
));
81 /* Helpers to generate midgard_instruction's using macro magic, since every
82 * driver seems to do it that way */
84 #define EMIT(op, ...) emit_mir_instruction(ctx, v_##op(__VA_ARGS__));
85 #define SWIZZLE_XXXX SWIZZLE(COMPONENT_X, COMPONENT_X, COMPONENT_X, COMPONENT_X)
86 #define SWIZZLE_XYXX SWIZZLE(COMPONENT_X, COMPONENT_Y, COMPONENT_X, COMPONENT_X)
87 #define SWIZZLE_XYZX SWIZZLE(COMPONENT_X, COMPONENT_Y, COMPONENT_Z, COMPONENT_X)
88 #define SWIZZLE_XYZW SWIZZLE(COMPONENT_X, COMPONENT_Y, COMPONENT_Z, COMPONENT_W)
89 #define SWIZZLE_XYXZ SWIZZLE(COMPONENT_X, COMPONENT_Y, COMPONENT_X, COMPONENT_Z)
90 #define SWIZZLE_WWWW SWIZZLE(COMPONENT_W, COMPONENT_W, COMPONENT_W, COMPONENT_W)
92 static inline unsigned
93 swizzle_of(unsigned comp
)
105 unreachable("Invalid component count");
109 static inline unsigned
110 mask_of(unsigned nr_comp
)
112 return (1 << nr_comp
) - 1;
115 #define M_LOAD_STORE(name, rname, uname) \
116 static midgard_instruction m_##name(unsigned ssa, unsigned address) { \
117 midgard_instruction i = { \
118 .type = TAG_LOAD_STORE_4, \
125 .op = midgard_op_##name, \
127 .swizzle = SWIZZLE_XYZW, \
135 #define M_LOAD(name) M_LOAD_STORE(name, dest, src0)
136 #define M_STORE(name) M_LOAD_STORE(name, src0, dest)
138 /* Inputs a NIR ALU source, with modifiers attached if necessary, and outputs
139 * the corresponding Midgard source */
141 static midgard_vector_alu_src
142 vector_alu_modifiers(nir_alu_src
*src
, bool is_int
)
144 if (!src
) return blank_alu_src
;
146 midgard_vector_alu_src alu_src
= {
149 .half
= 0, /* TODO */
150 .swizzle
= SWIZZLE_FROM_ARRAY(src
->swizzle
)
154 /* TODO: sign-extend/zero-extend */
155 alu_src
.mod
= midgard_int_normal
;
157 /* These should have been lowered away */
158 assert(!(src
->abs
|| src
->negate
));
160 alu_src
.mod
= (src
->abs
<< 0) | (src
->negate
<< 1);
166 /* load/store instructions have both 32-bit and 16-bit variants, depending on
167 * whether we are using vectors composed of highp or mediump. At the moment, we
168 * don't support half-floats -- this requires changes in other parts of the
169 * compiler -- therefore the 16-bit versions are commented out. */
171 //M_LOAD(ld_attr_16);
173 //M_LOAD(ld_vary_16);
175 //M_LOAD(ld_uniform_16);
176 M_LOAD(ld_uniform_32
);
177 M_LOAD(ld_color_buffer_8
);
178 //M_STORE(st_vary_16);
180 M_STORE(st_cubemap_coords
);
182 static midgard_instruction
183 v_alu_br_compact_cond(midgard_jmp_writeout_op op
, unsigned tag
, signed offset
, unsigned cond
)
185 midgard_branch_cond branch
= {
193 memcpy(&compact
, &branch
, sizeof(branch
));
195 midgard_instruction ins
= {
197 .unit
= ALU_ENAB_BR_COMPACT
,
198 .prepacked_branch
= true,
199 .compact_branch
= true,
200 .br_compact
= compact
203 if (op
== midgard_jmp_writeout_op_writeout
)
209 static midgard_instruction
210 v_branch(bool conditional
, bool invert
)
212 midgard_instruction ins
= {
214 .unit
= ALU_ENAB_BRANCH
,
215 .compact_branch
= true,
217 .conditional
= conditional
,
218 .invert_conditional
= invert
225 static midgard_branch_extended
226 midgard_create_branch_extended( midgard_condition cond
,
227 midgard_jmp_writeout_op op
,
229 signed quadword_offset
)
231 /* For unclear reasons, the condition code is repeated 8 times */
232 uint16_t duplicated_cond
=
242 midgard_branch_extended branch
= {
244 .dest_tag
= dest_tag
,
245 .offset
= quadword_offset
,
246 .cond
= duplicated_cond
253 attach_constants(compiler_context
*ctx
, midgard_instruction
*ins
, void *constants
, int name
)
255 ins
->has_constants
= true;
256 memcpy(&ins
->constants
, constants
, 16);
260 glsl_type_size(const struct glsl_type
*type
, bool bindless
)
262 return glsl_count_attribute_slots(type
, false);
265 /* Lower fdot2 to a vector multiplication followed by channel addition */
267 midgard_nir_lower_fdot2_body(nir_builder
*b
, nir_alu_instr
*alu
)
269 if (alu
->op
!= nir_op_fdot2
)
272 b
->cursor
= nir_before_instr(&alu
->instr
);
274 nir_ssa_def
*src0
= nir_ssa_for_alu_src(b
, alu
, 0);
275 nir_ssa_def
*src1
= nir_ssa_for_alu_src(b
, alu
, 1);
277 nir_ssa_def
*product
= nir_fmul(b
, src0
, src1
);
279 nir_ssa_def
*sum
= nir_fadd(b
,
280 nir_channel(b
, product
, 0),
281 nir_channel(b
, product
, 1));
283 /* Replace the fdot2 with this sum */
284 nir_ssa_def_rewrite_uses(&alu
->dest
.dest
.ssa
, nir_src_for_ssa(sum
));
288 midgard_nir_sysval_for_intrinsic(nir_intrinsic_instr
*instr
)
290 switch (instr
->intrinsic
) {
291 case nir_intrinsic_load_viewport_scale
:
292 return PAN_SYSVAL_VIEWPORT_SCALE
;
293 case nir_intrinsic_load_viewport_offset
:
294 return PAN_SYSVAL_VIEWPORT_OFFSET
;
301 midgard_nir_assign_sysval_body(compiler_context
*ctx
, nir_instr
*instr
)
305 if (instr
->type
== nir_instr_type_intrinsic
) {
306 nir_intrinsic_instr
*intr
= nir_instr_as_intrinsic(instr
);
307 sysval
= midgard_nir_sysval_for_intrinsic(intr
);
313 /* We have a sysval load; check if it's already been assigned */
315 if (_mesa_hash_table_u64_search(ctx
->sysval_to_id
, sysval
))
318 /* It hasn't -- so assign it now! */
320 unsigned id
= ctx
->sysval_count
++;
321 _mesa_hash_table_u64_insert(ctx
->sysval_to_id
, sysval
, (void *) ((uintptr_t) id
+ 1));
322 ctx
->sysvals
[id
] = sysval
;
326 midgard_nir_assign_sysvals(compiler_context
*ctx
, nir_shader
*shader
)
328 ctx
->sysval_count
= 0;
330 nir_foreach_function(function
, shader
) {
331 if (!function
->impl
) continue;
333 nir_foreach_block(block
, function
->impl
) {
334 nir_foreach_instr_safe(instr
, block
) {
335 midgard_nir_assign_sysval_body(ctx
, instr
);
342 midgard_nir_lower_fdot2(nir_shader
*shader
)
344 bool progress
= false;
346 nir_foreach_function(function
, shader
) {
347 if (!function
->impl
) continue;
350 nir_builder
*b
= &_b
;
351 nir_builder_init(b
, function
->impl
);
353 nir_foreach_block(block
, function
->impl
) {
354 nir_foreach_instr_safe(instr
, block
) {
355 if (instr
->type
!= nir_instr_type_alu
) continue;
357 nir_alu_instr
*alu
= nir_instr_as_alu(instr
);
358 midgard_nir_lower_fdot2_body(b
, alu
);
364 nir_metadata_preserve(function
->impl
, nir_metadata_block_index
| nir_metadata_dominance
);
372 optimise_nir(nir_shader
*nir
)
375 unsigned lower_flrp
=
376 (nir
->options
->lower_flrp16
? 16 : 0) |
377 (nir
->options
->lower_flrp32
? 32 : 0) |
378 (nir
->options
->lower_flrp64
? 64 : 0);
380 NIR_PASS(progress
, nir
, nir_lower_regs_to_ssa
);
381 NIR_PASS(progress
, nir
, midgard_nir_lower_fdot2
);
382 NIR_PASS(progress
, nir
, nir_lower_idiv
);
384 nir_lower_tex_options lower_tex_options
= {
389 NIR_PASS(progress
, nir
, nir_lower_tex
, &lower_tex_options
);
394 NIR_PASS(progress
, nir
, nir_lower_var_copies
);
395 NIR_PASS(progress
, nir
, nir_lower_vars_to_ssa
);
397 NIR_PASS(progress
, nir
, nir_copy_prop
);
398 NIR_PASS(progress
, nir
, nir_opt_dce
);
399 NIR_PASS(progress
, nir
, nir_opt_dead_cf
);
400 NIR_PASS(progress
, nir
, nir_opt_cse
);
401 NIR_PASS(progress
, nir
, nir_opt_peephole_select
, 64, false, true);
402 NIR_PASS(progress
, nir
, nir_opt_algebraic
);
403 NIR_PASS(progress
, nir
, nir_opt_constant_folding
);
405 if (lower_flrp
!= 0) {
406 bool lower_flrp_progress
= false;
407 NIR_PASS(lower_flrp_progress
,
411 false /* always_precise */,
412 nir
->options
->lower_ffma
);
413 if (lower_flrp_progress
) {
414 NIR_PASS(progress
, nir
,
415 nir_opt_constant_folding
);
419 /* Nothing should rematerialize any flrps, so we only
420 * need to do this lowering once.
425 NIR_PASS(progress
, nir
, nir_opt_undef
);
426 NIR_PASS(progress
, nir
, nir_opt_loop_unroll
,
429 nir_var_function_temp
);
431 /* TODO: Enable vectorize when merged upstream */
432 // NIR_PASS(progress, nir, nir_opt_vectorize);
435 /* Must be run at the end to prevent creation of fsin/fcos ops */
436 NIR_PASS(progress
, nir
, midgard_nir_scale_trig
);
441 NIR_PASS(progress
, nir
, nir_opt_dce
);
442 NIR_PASS(progress
, nir
, nir_opt_algebraic
);
443 NIR_PASS(progress
, nir
, nir_opt_constant_folding
);
444 NIR_PASS(progress
, nir
, nir_copy_prop
);
447 NIR_PASS(progress
, nir
, nir_opt_algebraic_late
);
449 /* We implement booleans as 32-bit 0/~0 */
450 NIR_PASS(progress
, nir
, nir_lower_bool_to_int32
);
452 /* Now that booleans are lowered, we can run out late opts */
453 NIR_PASS(progress
, nir
, midgard_nir_lower_algebraic_late
);
455 /* Lower mods for float ops only. Integer ops don't support modifiers
456 * (saturate doesn't make sense on integers, neg/abs require dedicated
459 NIR_PASS(progress
, nir
, nir_lower_to_source_mods
, nir_lower_float_source_mods
);
460 NIR_PASS(progress
, nir
, nir_copy_prop
);
461 NIR_PASS(progress
, nir
, nir_opt_dce
);
463 /* Take us out of SSA */
464 NIR_PASS(progress
, nir
, nir_lower_locals_to_regs
);
465 NIR_PASS(progress
, nir
, nir_convert_from_ssa
, true);
467 /* We are a vector architecture; write combine where possible */
468 NIR_PASS(progress
, nir
, nir_move_vec_src_uses_to_dest
);
469 NIR_PASS(progress
, nir
, nir_lower_vec_to_movs
);
471 NIR_PASS(progress
, nir
, nir_opt_dce
);
474 /* Front-half of aliasing the SSA slots, merely by inserting the flag in the
475 * appropriate hash table. Intentional off-by-one to avoid confusing NULL with
476 * r0. See the comments in compiler_context */
479 alias_ssa(compiler_context
*ctx
, int dest
, int src
)
481 _mesa_hash_table_u64_insert(ctx
->ssa_to_alias
, dest
+ 1, (void *) ((uintptr_t) src
+ 1));
482 _mesa_set_add(ctx
->leftover_ssa_to_alias
, (void *) (uintptr_t) (dest
+ 1));
485 /* ...or undo it, after which the original index will be used (dummy move should be emitted alongside this) */
488 unalias_ssa(compiler_context
*ctx
, int dest
)
490 _mesa_hash_table_u64_remove(ctx
->ssa_to_alias
, dest
+ 1);
491 /* TODO: Remove from leftover or no? */
494 /* Do not actually emit a load; instead, cache the constant for inlining */
497 emit_load_const(compiler_context
*ctx
, nir_load_const_instr
*instr
)
499 nir_ssa_def def
= instr
->def
;
501 float *v
= rzalloc_array(NULL
, float, 4);
502 nir_const_load_to_arr(v
, instr
, f32
);
503 _mesa_hash_table_u64_insert(ctx
->ssa_constants
, def
.index
+ 1, v
);
507 nir_src_index(compiler_context
*ctx
, nir_src
*src
)
510 return src
->ssa
->index
;
512 assert(!src
->reg
.indirect
);
513 return ctx
->func
->impl
->ssa_alloc
+ src
->reg
.reg
->index
;
518 nir_dest_index(compiler_context
*ctx
, nir_dest
*dst
)
521 return dst
->ssa
.index
;
523 assert(!dst
->reg
.indirect
);
524 return ctx
->func
->impl
->ssa_alloc
+ dst
->reg
.reg
->index
;
529 nir_alu_src_index(compiler_context
*ctx
, nir_alu_src
*src
)
531 return nir_src_index(ctx
, &src
->src
);
535 nir_is_non_scalar_swizzle(nir_alu_src
*src
, unsigned nr_components
)
537 unsigned comp
= src
->swizzle
[0];
539 for (unsigned c
= 1; c
< nr_components
; ++c
) {
540 if (src
->swizzle
[c
] != comp
)
547 /* Midgard puts scalar conditionals in r31.w; move an arbitrary source (the
548 * output of a conditional test) into that register */
551 emit_condition(compiler_context
*ctx
, nir_src
*src
, bool for_branch
, unsigned component
)
553 int condition
= nir_src_index(ctx
, src
);
555 /* Source to swizzle the desired component into w */
557 const midgard_vector_alu_src alu_src
= {
558 .swizzle
= SWIZZLE(component
, component
, component
, component
),
561 /* There is no boolean move instruction. Instead, we simulate a move by
562 * ANDing the condition with itself to get it into r31.w */
564 midgard_instruction ins
= {
567 /* We need to set the conditional as close as possible */
568 .precede_break
= true,
569 .unit
= for_branch
? UNIT_SMUL
: UNIT_SADD
,
574 .dest
= SSA_FIXED_REGISTER(31),
578 .op
= midgard_alu_op_iand
,
579 .outmod
= midgard_outmod_int_wrap
,
580 .reg_mode
= midgard_reg_mode_32
,
581 .dest_override
= midgard_dest_override_none
,
582 .mask
= (0x3 << 6), /* w */
583 .src1
= vector_alu_srco_unsigned(alu_src
),
584 .src2
= vector_alu_srco_unsigned(alu_src
)
588 emit_mir_instruction(ctx
, ins
);
591 /* Or, for mixed conditions (with csel_v), here's a vector version using all of
595 emit_condition_mixed(compiler_context
*ctx
, nir_alu_src
*src
, unsigned nr_comp
)
597 int condition
= nir_src_index(ctx
, &src
->src
);
599 /* Source to swizzle the desired component into w */
601 const midgard_vector_alu_src alu_src
= {
602 .swizzle
= SWIZZLE_FROM_ARRAY(src
->swizzle
),
605 /* There is no boolean move instruction. Instead, we simulate a move by
606 * ANDing the condition with itself to get it into r31.w */
608 midgard_instruction ins
= {
610 .precede_break
= true,
614 .dest
= SSA_FIXED_REGISTER(31),
617 .op
= midgard_alu_op_iand
,
618 .outmod
= midgard_outmod_int_wrap
,
619 .reg_mode
= midgard_reg_mode_32
,
620 .dest_override
= midgard_dest_override_none
,
621 .mask
= expand_writemask(mask_of(nr_comp
)),
622 .src1
= vector_alu_srco_unsigned(alu_src
),
623 .src2
= vector_alu_srco_unsigned(alu_src
)
627 emit_mir_instruction(ctx
, ins
);
632 /* Likewise, indirect offsets are put in r27.w. TODO: Allow componentwise
633 * pinning to eliminate this move in all known cases */
636 emit_indirect_offset(compiler_context
*ctx
, nir_src
*src
)
638 int offset
= nir_src_index(ctx
, src
);
640 midgard_instruction ins
= {
643 .src0
= SSA_UNUSED_1
,
645 .dest
= SSA_FIXED_REGISTER(REGISTER_OFFSET
),
648 .op
= midgard_alu_op_imov
,
649 .outmod
= midgard_outmod_int_wrap
,
650 .reg_mode
= midgard_reg_mode_32
,
651 .dest_override
= midgard_dest_override_none
,
652 .mask
= (0x3 << 6), /* w */
653 .src1
= vector_alu_srco_unsigned(zero_alu_src
),
654 .src2
= vector_alu_srco_unsigned(blank_alu_src_xxxx
)
658 emit_mir_instruction(ctx
, ins
);
661 #define ALU_CASE(nir, _op) \
663 op = midgard_alu_op_##_op; \
666 nir_is_fzero_constant(nir_src src
)
668 if (!nir_src_is_const(src
))
671 for (unsigned c
= 0; c
< nir_src_num_components(src
); ++c
) {
672 if (nir_src_comp_as_float(src
, c
) != 0.0)
680 emit_alu(compiler_context
*ctx
, nir_alu_instr
*instr
)
682 bool is_ssa
= instr
->dest
.dest
.is_ssa
;
684 unsigned dest
= nir_dest_index(ctx
, &instr
->dest
.dest
);
685 unsigned nr_components
= is_ssa
? instr
->dest
.dest
.ssa
.num_components
: instr
->dest
.dest
.reg
.reg
->num_components
;
686 unsigned nr_inputs
= nir_op_infos
[instr
->op
].num_inputs
;
688 /* Most Midgard ALU ops have a 1:1 correspondance to NIR ops; these are
689 * supported. A few do not and are commented for now. Also, there are a
690 * number of NIR ops which Midgard does not support and need to be
691 * lowered, also TODO. This switch block emits the opcode and calling
692 * convention of the Midgard instruction; actual packing is done in
698 ALU_CASE(fadd
, fadd
);
699 ALU_CASE(fmul
, fmul
);
700 ALU_CASE(fmin
, fmin
);
701 ALU_CASE(fmax
, fmax
);
702 ALU_CASE(imin
, imin
);
703 ALU_CASE(imax
, imax
);
704 ALU_CASE(umin
, umin
);
705 ALU_CASE(umax
, umax
);
706 ALU_CASE(ffloor
, ffloor
);
707 ALU_CASE(fround_even
, froundeven
);
708 ALU_CASE(ftrunc
, ftrunc
);
709 ALU_CASE(fceil
, fceil
);
710 ALU_CASE(fdot3
, fdot3
);
711 ALU_CASE(fdot4
, fdot4
);
712 ALU_CASE(iadd
, iadd
);
713 ALU_CASE(isub
, isub
);
714 ALU_CASE(imul
, imul
);
716 /* Zero shoved as second-arg */
717 ALU_CASE(iabs
, iabsdiff
);
721 ALU_CASE(feq32
, feq
);
722 ALU_CASE(fne32
, fne
);
723 ALU_CASE(flt32
, flt
);
724 ALU_CASE(ieq32
, ieq
);
725 ALU_CASE(ine32
, ine
);
726 ALU_CASE(ilt32
, ilt
);
727 ALU_CASE(ult32
, ult
);
729 /* We don't have a native b2f32 instruction. Instead, like many
730 * GPUs, we exploit booleans as 0/~0 for false/true, and
731 * correspondingly AND
732 * by 1.0 to do the type conversion. For the moment, prime us
735 * iand [whatever], #0
737 * At the end of emit_alu (as MIR), we'll fix-up the constant
740 ALU_CASE(b2f32
, iand
);
741 ALU_CASE(b2i32
, iand
);
743 /* Likewise, we don't have a dedicated f2b32 instruction, but
744 * we can do a "not equal to 0.0" test. */
746 ALU_CASE(f2b32
, fne
);
747 ALU_CASE(i2b32
, ine
);
749 ALU_CASE(frcp
, frcp
);
750 ALU_CASE(frsq
, frsqrt
);
751 ALU_CASE(fsqrt
, fsqrt
);
752 ALU_CASE(fexp2
, fexp2
);
753 ALU_CASE(flog2
, flog2
);
755 ALU_CASE(f2i32
, f2i_rtz
);
756 ALU_CASE(f2u32
, f2u_rtz
);
757 ALU_CASE(i2f32
, i2f_rtz
);
758 ALU_CASE(u2f32
, u2f_rtz
);
760 ALU_CASE(fsin
, fsin
);
761 ALU_CASE(fcos
, fcos
);
763 /* Second op implicit #0 */
764 ALU_CASE(inot
, inor
);
765 ALU_CASE(iand
, iand
);
767 ALU_CASE(ixor
, ixor
);
768 ALU_CASE(ishl
, ishl
);
769 ALU_CASE(ishr
, iasr
);
770 ALU_CASE(ushr
, ilsr
);
772 ALU_CASE(b32all_fequal2
, fball_eq
);
773 ALU_CASE(b32all_fequal3
, fball_eq
);
774 ALU_CASE(b32all_fequal4
, fball_eq
);
776 ALU_CASE(b32any_fnequal2
, fbany_neq
);
777 ALU_CASE(b32any_fnequal3
, fbany_neq
);
778 ALU_CASE(b32any_fnequal4
, fbany_neq
);
780 ALU_CASE(b32all_iequal2
, iball_eq
);
781 ALU_CASE(b32all_iequal3
, iball_eq
);
782 ALU_CASE(b32all_iequal4
, iball_eq
);
784 ALU_CASE(b32any_inequal2
, ibany_neq
);
785 ALU_CASE(b32any_inequal3
, ibany_neq
);
786 ALU_CASE(b32any_inequal4
, ibany_neq
);
788 /* Source mods will be shoved in later */
789 ALU_CASE(fabs
, fmov
);
790 ALU_CASE(fneg
, fmov
);
791 ALU_CASE(fsat
, fmov
);
793 /* For greater-or-equal, we lower to less-or-equal and flip the
801 instr
->op
== nir_op_fge
? midgard_alu_op_fle
:
802 instr
->op
== nir_op_fge32
? midgard_alu_op_fle
:
803 instr
->op
== nir_op_ige32
? midgard_alu_op_ile
:
804 instr
->op
== nir_op_uge32
? midgard_alu_op_ule
:
807 /* Swap via temporary */
808 nir_alu_src temp
= instr
->src
[1];
809 instr
->src
[1] = instr
->src
[0];
810 instr
->src
[0] = temp
;
815 case nir_op_b32csel
: {
816 /* Midgard features both fcsel and icsel, depending on
817 * the type of the arguments/output. However, as long
818 * as we're careful we can _always_ use icsel and
819 * _never_ need fcsel, since the latter does additional
820 * floating-point-specific processing whereas the
821 * former just moves bits on the wire. It's not obvious
822 * why these are separate opcodes, save for the ability
823 * to do things like sat/pos/abs/neg for free */
825 bool mixed
= nir_is_non_scalar_swizzle(&instr
->src
[0], nr_components
);
826 op
= mixed
? midgard_alu_op_icsel_v
: midgard_alu_op_icsel
;
828 /* csel works as a two-arg in Midgard, since the condition is hardcoded in r31.w */
831 /* Emit the condition into r31 */
834 emit_condition_mixed(ctx
, &instr
->src
[0], nr_components
);
836 emit_condition(ctx
, &instr
->src
[0].src
, false, instr
->src
[0].swizzle
[0]);
838 /* The condition is the first argument; move the other
839 * arguments up one to be a binary instruction for
842 memmove(instr
->src
, instr
->src
+ 1, 2 * sizeof(nir_alu_src
));
847 DBG("Unhandled ALU op %s\n", nir_op_infos
[instr
->op
].name
);
852 /* Midgard can perform certain modifiers on output of an ALU op */
855 if (midgard_is_integer_out_op(op
)) {
856 outmod
= midgard_outmod_int_wrap
;
858 bool sat
= instr
->dest
.saturate
|| instr
->op
== nir_op_fsat
;
859 outmod
= sat
? midgard_outmod_sat
: midgard_outmod_none
;
862 /* fmax(a, 0.0) can turn into a .pos modifier as an optimization */
864 if (instr
->op
== nir_op_fmax
) {
865 if (nir_is_fzero_constant(instr
->src
[0].src
)) {
866 op
= midgard_alu_op_fmov
;
868 outmod
= midgard_outmod_pos
;
869 instr
->src
[0] = instr
->src
[1];
870 } else if (nir_is_fzero_constant(instr
->src
[1].src
)) {
871 op
= midgard_alu_op_fmov
;
873 outmod
= midgard_outmod_pos
;
877 /* Fetch unit, quirks, etc information */
878 unsigned opcode_props
= alu_opcode_props
[op
].props
;
879 bool quirk_flipped_r24
= opcode_props
& QUIRK_FLIPPED_R24
;
881 /* src0 will always exist afaik, but src1 will not for 1-argument
882 * instructions. The latter can only be fetched if the instruction
883 * needs it, or else we may segfault. */
885 unsigned src0
= nir_alu_src_index(ctx
, &instr
->src
[0]);
886 unsigned src1
= nr_inputs
== 2 ? nir_alu_src_index(ctx
, &instr
->src
[1]) : SSA_UNUSED_0
;
888 /* Rather than use the instruction generation helpers, we do it
889 * ourselves here to avoid the mess */
891 midgard_instruction ins
= {
894 .src0
= quirk_flipped_r24
? SSA_UNUSED_1
: src0
,
895 .src1
= quirk_flipped_r24
? src0
: src1
,
900 nir_alu_src
*nirmods
[2] = { NULL
};
902 if (nr_inputs
== 2) {
903 nirmods
[0] = &instr
->src
[0];
904 nirmods
[1] = &instr
->src
[1];
905 } else if (nr_inputs
== 1) {
906 nirmods
[quirk_flipped_r24
] = &instr
->src
[0];
911 /* These were lowered to a move, so apply the corresponding mod */
913 if (instr
->op
== nir_op_fneg
|| instr
->op
== nir_op_fabs
) {
914 nir_alu_src
*s
= nirmods
[quirk_flipped_r24
];
916 if (instr
->op
== nir_op_fneg
)
917 s
->negate
= !s
->negate
;
919 if (instr
->op
== nir_op_fabs
)
923 bool is_int
= midgard_is_integer_op(op
);
925 midgard_vector_alu alu
= {
927 .reg_mode
= midgard_reg_mode_32
,
928 .dest_override
= midgard_dest_override_none
,
931 /* Writemask only valid for non-SSA NIR */
932 .mask
= expand_writemask(mask_of(nr_components
)),
934 .src1
= vector_alu_srco_unsigned(vector_alu_modifiers(nirmods
[0], is_int
)),
935 .src2
= vector_alu_srco_unsigned(vector_alu_modifiers(nirmods
[1], is_int
)),
938 /* Apply writemask if non-SSA, keeping in mind that we can't write to components that don't exist */
941 alu
.mask
&= expand_writemask(instr
->dest
.write_mask
);
945 /* Late fixup for emulated instructions */
947 if (instr
->op
== nir_op_b2f32
|| instr
->op
== nir_op_b2i32
) {
948 /* Presently, our second argument is an inline #0 constant.
949 * Switch over to an embedded 1.0 constant (that can't fit
950 * inline, since we're 32-bit, not 16-bit like the inline
953 ins
.ssa_args
.inline_constant
= false;
954 ins
.ssa_args
.src1
= SSA_FIXED_REGISTER(REGISTER_CONSTANT
);
955 ins
.has_constants
= true;
957 if (instr
->op
== nir_op_b2f32
) {
958 ins
.constants
[0] = 1.0f
;
960 /* Type pun it into place */
962 memcpy(&ins
.constants
[0], &one
, sizeof(uint32_t));
965 ins
.alu
.src2
= vector_alu_srco_unsigned(blank_alu_src_xxxx
);
966 } else if (nr_inputs
== 1 && !quirk_flipped_r24
) {
967 /* Lots of instructions need a 0 plonked in */
968 ins
.ssa_args
.inline_constant
= false;
969 ins
.ssa_args
.src1
= SSA_FIXED_REGISTER(REGISTER_CONSTANT
);
970 ins
.has_constants
= true;
971 ins
.constants
[0] = 0.0f
;
972 ins
.alu
.src2
= vector_alu_srco_unsigned(blank_alu_src_xxxx
);
973 } else if (instr
->op
== nir_op_inot
) {
974 /* ~b = ~(b & b), so duplicate the source */
975 ins
.ssa_args
.src1
= ins
.ssa_args
.src0
;
976 ins
.alu
.src2
= ins
.alu
.src1
;
979 if ((opcode_props
& UNITS_ALL
) == UNIT_VLUT
) {
980 /* To avoid duplicating the lookup tables (probably), true LUT
981 * instructions can only operate as if they were scalars. Lower
982 * them here by changing the component. */
984 uint8_t original_swizzle
[4];
985 memcpy(original_swizzle
, nirmods
[0]->swizzle
, sizeof(nirmods
[0]->swizzle
));
987 for (int i
= 0; i
< nr_components
; ++i
) {
988 /* Mask the associated component, dropping the
989 * instruction if needed */
991 ins
.alu
.mask
= (0x3) << (2 * i
);
992 ins
.alu
.mask
&= alu
.mask
;
997 for (int j
= 0; j
< 4; ++j
)
998 nirmods
[0]->swizzle
[j
] = original_swizzle
[i
]; /* Pull from the correct component */
1000 ins
.alu
.src1
= vector_alu_srco_unsigned(vector_alu_modifiers(nirmods
[0], is_int
));
1001 emit_mir_instruction(ctx
, ins
);
1004 emit_mir_instruction(ctx
, ins
);
1011 emit_uniform_read(compiler_context
*ctx
, unsigned dest
, unsigned offset
, nir_src
*indirect_offset
)
1013 /* TODO: half-floats */
1015 if (!indirect_offset
&& offset
< ctx
->uniform_cutoff
) {
1016 /* Fast path: For the first 16 uniforms, direct accesses are
1017 * 0-cycle, since they're just a register fetch in the usual
1018 * case. So, we alias the registers while we're still in
1021 int reg_slot
= 23 - offset
;
1022 alias_ssa(ctx
, dest
, SSA_FIXED_REGISTER(reg_slot
));
1024 /* Otherwise, read from the 'special' UBO to access
1025 * higher-indexed uniforms, at a performance cost. More
1026 * generally, we're emitting a UBO read instruction. */
1028 midgard_instruction ins
= m_ld_uniform_32(dest
, offset
);
1030 /* TODO: Don't split */
1031 ins
.load_store
.varying_parameters
= (offset
& 7) << 7;
1032 ins
.load_store
.address
= offset
>> 3;
1034 if (indirect_offset
) {
1035 emit_indirect_offset(ctx
, indirect_offset
);
1036 ins
.load_store
.unknown
= 0x8700; /* xxx: what is this? */
1038 ins
.load_store
.unknown
= 0x1E00; /* xxx: what is this? */
1041 emit_mir_instruction(ctx
, ins
);
1047 compiler_context
*ctx
,
1048 unsigned dest
, unsigned offset
,
1049 unsigned nr_comp
, unsigned component
,
1050 nir_src
*indirect_offset
)
1052 /* XXX: Half-floats? */
1053 /* TODO: swizzle, mask */
1055 midgard_instruction ins
= m_ld_vary_32(dest
, offset
);
1056 ins
.load_store
.mask
= mask_of(nr_comp
);
1057 ins
.load_store
.swizzle
= SWIZZLE_XYZW
>> (2 * component
);
1059 midgard_varying_parameter p
= {
1061 .interpolation
= midgard_interp_default
,
1062 .flat
= /*var->data.interpolation == INTERP_MODE_FLAT*/ 0
1066 memcpy(&u
, &p
, sizeof(p
));
1067 ins
.load_store
.varying_parameters
= u
;
1069 if (indirect_offset
) {
1070 /* We need to add in the dynamic index, moved to r27.w */
1071 emit_indirect_offset(ctx
, indirect_offset
);
1072 ins
.load_store
.unknown
= 0x79e; /* xxx: what is this? */
1074 /* Just a direct load */
1075 ins
.load_store
.unknown
= 0x1e9e; /* xxx: what is this? */
1078 emit_mir_instruction(ctx
, ins
);
1082 emit_sysval_read(compiler_context
*ctx
, nir_intrinsic_instr
*instr
)
1084 /* First, pull out the destination */
1085 unsigned dest
= nir_dest_index(ctx
, &instr
->dest
);
1087 /* Now, figure out which uniform this is */
1088 int sysval
= midgard_nir_sysval_for_intrinsic(instr
);
1089 void *val
= _mesa_hash_table_u64_search(ctx
->sysval_to_id
, sysval
);
1091 /* Sysvals are prefix uniforms */
1092 unsigned uniform
= ((uintptr_t) val
) - 1;
1094 /* Emit the read itself -- this is never indirect */
1095 emit_uniform_read(ctx
, dest
, uniform
, NULL
);
1098 /* Reads RGBA8888 value from the tilebuffer and converts to a RGBA32F register,
1099 * using scalar ops functional on earlier Midgard generations. Newer Midgard
1100 * generations have faster vectorized reads. This operation is for blend
1101 * shaders in particular; reading the tilebuffer from the fragment shader
1102 * remains an open problem. */
1105 emit_fb_read_blend_scalar(compiler_context
*ctx
, unsigned reg
)
1107 midgard_instruction ins
= m_ld_color_buffer_8(reg
, 0);
1108 ins
.load_store
.swizzle
= 0; /* xxxx */
1110 /* Read each component sequentially */
1112 for (unsigned c
= 0; c
< 4; ++c
) {
1113 ins
.load_store
.mask
= (1 << c
);
1114 ins
.load_store
.unknown
= c
;
1115 emit_mir_instruction(ctx
, ins
);
1118 /* vadd.u2f hr2, zext(hr2), #0 */
1120 midgard_vector_alu_src alu_src
= blank_alu_src
;
1121 alu_src
.mod
= midgard_int_zero_extend
;
1122 alu_src
.half
= true;
1124 midgard_instruction u2f
= {
1128 .src1
= SSA_UNUSED_0
,
1130 .inline_constant
= true
1133 .op
= midgard_alu_op_u2f_rtz
,
1134 .reg_mode
= midgard_reg_mode_16
,
1135 .dest_override
= midgard_dest_override_none
,
1137 .src1
= vector_alu_srco_unsigned(alu_src
),
1138 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
1142 emit_mir_instruction(ctx
, u2f
);
1144 /* vmul.fmul.sat r1, hr2, #0.00392151 */
1148 midgard_instruction fmul
= {
1150 .inline_constant
= _mesa_float_to_half(1.0 / 255.0),
1154 .src1
= SSA_UNUSED_0
,
1155 .inline_constant
= true
1158 .op
= midgard_alu_op_fmul
,
1159 .reg_mode
= midgard_reg_mode_32
,
1160 .dest_override
= midgard_dest_override_none
,
1161 .outmod
= midgard_outmod_sat
,
1163 .src1
= vector_alu_srco_unsigned(alu_src
),
1164 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
1168 emit_mir_instruction(ctx
, fmul
);
1172 emit_intrinsic(compiler_context
*ctx
, nir_intrinsic_instr
*instr
)
1174 unsigned offset
, reg
;
1176 switch (instr
->intrinsic
) {
1177 case nir_intrinsic_discard_if
:
1178 emit_condition(ctx
, &instr
->src
[0], true, COMPONENT_X
);
1182 case nir_intrinsic_discard
: {
1183 bool conditional
= instr
->intrinsic
== nir_intrinsic_discard_if
;
1184 struct midgard_instruction discard
= v_branch(conditional
, false);
1185 discard
.branch
.target_type
= TARGET_DISCARD
;
1186 emit_mir_instruction(ctx
, discard
);
1188 ctx
->can_discard
= true;
1192 case nir_intrinsic_load_uniform
:
1193 case nir_intrinsic_load_input
:
1194 offset
= nir_intrinsic_base(instr
);
1196 unsigned nr_comp
= nir_intrinsic_dest_components(instr
);
1197 bool direct
= nir_src_is_const(instr
->src
[0]);
1200 offset
+= nir_src_as_uint(instr
->src
[0]);
1203 /* We may need to apply a fractional offset */
1204 int component
= instr
->intrinsic
== nir_intrinsic_load_input
?
1205 nir_intrinsic_component(instr
) : 0;
1206 reg
= nir_dest_index(ctx
, &instr
->dest
);
1208 if (instr
->intrinsic
== nir_intrinsic_load_uniform
&& !ctx
->is_blend
) {
1209 emit_uniform_read(ctx
, reg
, ctx
->sysval_count
+ offset
, !direct
? &instr
->src
[0] : NULL
);
1210 } else if (ctx
->stage
== MESA_SHADER_FRAGMENT
&& !ctx
->is_blend
) {
1211 emit_varying_read(ctx
, reg
, offset
, nr_comp
, component
, !direct
? &instr
->src
[0] : NULL
);
1212 } else if (ctx
->is_blend
) {
1213 /* For blend shaders, load the input color, which is
1214 * preloaded to r0 */
1216 midgard_instruction move
= v_mov(reg
, blank_alu_src
, SSA_FIXED_REGISTER(0));
1217 emit_mir_instruction(ctx
, move
);
1218 } else if (ctx
->stage
== MESA_SHADER_VERTEX
) {
1219 midgard_instruction ins
= m_ld_attr_32(reg
, offset
);
1220 ins
.load_store
.unknown
= 0x1E1E; /* XXX: What is this? */
1221 ins
.load_store
.mask
= mask_of(nr_comp
);
1222 emit_mir_instruction(ctx
, ins
);
1224 DBG("Unknown load\n");
1230 case nir_intrinsic_load_output
:
1231 assert(nir_src_is_const(instr
->src
[0]));
1232 reg
= nir_dest_index(ctx
, &instr
->dest
);
1234 if (ctx
->is_blend
) {
1236 emit_fb_read_blend_scalar(ctx
, reg
);
1238 DBG("Unknown output load\n");
1244 case nir_intrinsic_load_blend_const_color_rgba
: {
1245 assert(ctx
->is_blend
);
1246 reg
= nir_dest_index(ctx
, &instr
->dest
);
1248 /* Blend constants are embedded directly in the shader and
1249 * patched in, so we use some magic routing */
1251 midgard_instruction ins
= v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT
), blank_alu_src
, reg
);
1252 ins
.has_constants
= true;
1253 ins
.has_blend_constant
= true;
1254 emit_mir_instruction(ctx
, ins
);
1258 case nir_intrinsic_store_output
:
1259 assert(nir_src_is_const(instr
->src
[1]) && "no indirect outputs");
1261 offset
= nir_intrinsic_base(instr
) + nir_src_as_uint(instr
->src
[1]);
1263 reg
= nir_src_index(ctx
, &instr
->src
[0]);
1265 if (ctx
->stage
== MESA_SHADER_FRAGMENT
) {
1266 /* gl_FragColor is not emitted with load/store
1267 * instructions. Instead, it gets plonked into
1268 * r0 at the end of the shader and we do the
1269 * framebuffer writeout dance. TODO: Defer
1272 midgard_instruction move
= v_mov(reg
, blank_alu_src
, SSA_FIXED_REGISTER(0));
1273 emit_mir_instruction(ctx
, move
);
1275 /* Save the index we're writing to for later reference
1276 * in the epilogue */
1278 ctx
->fragment_output
= reg
;
1279 } else if (ctx
->stage
== MESA_SHADER_VERTEX
) {
1280 /* Varyings are written into one of two special
1281 * varying register, r26 or r27. The register itself is
1282 * selected as the register in the st_vary instruction,
1283 * minus the base of 26. E.g. write into r27 and then
1284 * call st_vary(1) */
1286 midgard_instruction ins
= v_mov(reg
, blank_alu_src
, SSA_FIXED_REGISTER(26));
1287 emit_mir_instruction(ctx
, ins
);
1289 /* We should have been vectorized. That also lets us
1290 * ignore the mask. because the mask component on
1291 * st_vary is (as far as I can tell) ignored [the blob
1292 * sets it to zero] */
1293 assert(nir_intrinsic_component(instr
) == 0);
1295 midgard_instruction st
= m_st_vary_32(SSA_FIXED_REGISTER(0), offset
);
1296 st
.load_store
.unknown
= 0x1E9E; /* XXX: What is this? */
1297 emit_mir_instruction(ctx
, st
);
1299 DBG("Unknown store\n");
1305 case nir_intrinsic_load_alpha_ref_float
:
1306 assert(instr
->dest
.is_ssa
);
1308 float ref_value
= ctx
->alpha_ref
;
1310 float *v
= ralloc_array(NULL
, float, 4);
1311 memcpy(v
, &ref_value
, sizeof(float));
1312 _mesa_hash_table_u64_insert(ctx
->ssa_constants
, instr
->dest
.ssa
.index
+ 1, v
);
1315 case nir_intrinsic_load_viewport_scale
:
1316 case nir_intrinsic_load_viewport_offset
:
1317 emit_sysval_read(ctx
, instr
);
1321 printf ("Unhandled intrinsic\n");
1328 midgard_tex_format(enum glsl_sampler_dim dim
)
1331 case GLSL_SAMPLER_DIM_2D
:
1332 case GLSL_SAMPLER_DIM_EXTERNAL
:
1335 case GLSL_SAMPLER_DIM_3D
:
1338 case GLSL_SAMPLER_DIM_CUBE
:
1339 return TEXTURE_CUBE
;
1342 DBG("Unknown sampler dim type\n");
1349 midgard_tex_op(nir_texop op
)
1354 return TEXTURE_OP_NORMAL
;
1356 return TEXTURE_OP_LOD
;
1358 unreachable("Unhanlded texture op");
1363 emit_tex(compiler_context
*ctx
, nir_tex_instr
*instr
)
1366 //assert (!instr->sampler);
1367 //assert (!instr->texture_array_size);
1369 /* Allocate registers via a round robin scheme to alternate between the two registers */
1370 int reg
= ctx
->texture_op_count
& 1;
1371 int in_reg
= reg
, out_reg
= reg
;
1373 /* Make room for the reg */
1375 if (ctx
->texture_index
[reg
] > -1)
1376 unalias_ssa(ctx
, ctx
->texture_index
[reg
]);
1378 int texture_index
= instr
->texture_index
;
1379 int sampler_index
= texture_index
;
1381 unsigned position_swizzle
= 0;
1383 for (unsigned i
= 0; i
< instr
->num_srcs
; ++i
) {
1384 int reg
= SSA_FIXED_REGISTER(REGISTER_TEXTURE_BASE
+ in_reg
);
1385 int index
= nir_src_index(ctx
, &instr
->src
[i
].src
);
1386 int nr_comp
= nir_src_num_components(instr
->src
[i
].src
);
1387 midgard_vector_alu_src alu_src
= blank_alu_src
;
1389 switch (instr
->src
[i
].src_type
) {
1390 case nir_tex_src_coord
: {
1391 if (instr
->sampler_dim
== GLSL_SAMPLER_DIM_CUBE
) {
1392 /* For cubemaps, we need to load coords into
1393 * special r27, and then use a special ld/st op
1394 * to select the face and copy the xy into the
1395 * texture register */
1397 alu_src
.swizzle
= SWIZZLE(COMPONENT_X
, COMPONENT_Y
, COMPONENT_Z
, COMPONENT_X
);
1399 midgard_instruction move
= v_mov(index
, alu_src
, SSA_FIXED_REGISTER(27));
1400 emit_mir_instruction(ctx
, move
);
1402 midgard_instruction st
= m_st_cubemap_coords(reg
, 0);
1403 st
.load_store
.unknown
= 0x24; /* XXX: What is this? */
1404 st
.load_store
.mask
= 0x3; /* xy */
1405 st
.load_store
.swizzle
= alu_src
.swizzle
;
1406 emit_mir_instruction(ctx
, st
);
1408 position_swizzle
= swizzle_of(2);
1410 position_swizzle
= alu_src
.swizzle
= swizzle_of(nr_comp
);
1412 midgard_instruction ins
= v_mov(index
, alu_src
, reg
);
1413 ins
.alu
.mask
= expand_writemask(mask_of(nr_comp
));
1414 emit_mir_instruction(ctx
, ins
);
1416 /* To the hardware, z is depth, w is array
1417 * layer. To NIR, z is array layer for a 2D
1420 bool has_array
= instr
->texture_array_size
> 0;
1421 bool is_2d
= instr
->sampler_dim
== GLSL_SAMPLER_DIM_2D
;
1423 if (is_2d
&& has_array
)
1424 position_swizzle
= SWIZZLE_XYXZ
;
1430 case nir_tex_src_bias
:
1431 case nir_tex_src_lod
: {
1432 /* To keep RA simple, we put the bias/LOD into the w
1433 * component of the input source, which is otherwise in xy */
1435 alu_src
.swizzle
= SWIZZLE_XXXX
;
1437 midgard_instruction ins
= v_mov(index
, alu_src
, reg
);
1438 ins
.alu
.mask
= expand_writemask(1 << COMPONENT_W
);
1439 emit_mir_instruction(ctx
, ins
);
1444 unreachable("Unknown texture source type\n");
1448 /* No helper to build texture words -- we do it all here */
1449 midgard_instruction ins
= {
1450 .type
= TAG_TEXTURE_4
,
1452 .op
= midgard_tex_op(instr
->op
),
1453 .format
= midgard_tex_format(instr
->sampler_dim
),
1454 .texture_handle
= texture_index
,
1455 .sampler_handle
= sampler_index
,
1457 /* TODO: Regalloc it in */
1458 .swizzle
= SWIZZLE_XYZW
,
1463 .in_reg_swizzle
= position_swizzle
,
1471 /* Set registers to read and write from the same place */
1472 ins
.texture
.in_reg_select
= in_reg
;
1473 ins
.texture
.out_reg_select
= out_reg
;
1475 /* Setup bias/LOD if necessary. Only register mode support right now.
1476 * TODO: Immediate mode for performance gains */
1478 if (instr
->op
== nir_texop_txb
|| instr
->op
== nir_texop_txl
) {
1479 ins
.texture
.lod_register
= true;
1481 midgard_tex_register_select sel
= {
1491 memcpy(&packed
, &sel
, sizeof(packed
));
1492 ins
.texture
.bias
= packed
;
1495 emit_mir_instruction(ctx
, ins
);
1497 /* Simultaneously alias the destination and emit a move for it. The move will be eliminated if possible */
1499 int o_reg
= REGISTER_TEXTURE_BASE
+ out_reg
, o_index
= nir_dest_index(ctx
, &instr
->dest
);
1500 alias_ssa(ctx
, o_index
, SSA_FIXED_REGISTER(o_reg
));
1501 ctx
->texture_index
[reg
] = o_index
;
1503 midgard_instruction ins2
= v_mov(SSA_FIXED_REGISTER(o_reg
), blank_alu_src
, o_index
);
1504 emit_mir_instruction(ctx
, ins2
);
1506 /* Used for .cont and .last hinting */
1507 ctx
->texture_op_count
++;
1511 emit_jump(compiler_context
*ctx
, nir_jump_instr
*instr
)
1513 switch (instr
->type
) {
1514 case nir_jump_break
: {
1515 /* Emit a branch out of the loop */
1516 struct midgard_instruction br
= v_branch(false, false);
1517 br
.branch
.target_type
= TARGET_BREAK
;
1518 br
.branch
.target_break
= ctx
->current_loop_depth
;
1519 emit_mir_instruction(ctx
, br
);
1526 DBG("Unknown jump type %d\n", instr
->type
);
1532 emit_instr(compiler_context
*ctx
, struct nir_instr
*instr
)
1534 switch (instr
->type
) {
1535 case nir_instr_type_load_const
:
1536 emit_load_const(ctx
, nir_instr_as_load_const(instr
));
1539 case nir_instr_type_intrinsic
:
1540 emit_intrinsic(ctx
, nir_instr_as_intrinsic(instr
));
1543 case nir_instr_type_alu
:
1544 emit_alu(ctx
, nir_instr_as_alu(instr
));
1547 case nir_instr_type_tex
:
1548 emit_tex(ctx
, nir_instr_as_tex(instr
));
1551 case nir_instr_type_jump
:
1552 emit_jump(ctx
, nir_instr_as_jump(instr
));
1555 case nir_instr_type_ssa_undef
:
1560 DBG("Unhandled instruction type\n");
1566 /* ALU instructions can inline or embed constants, which decreases register
1567 * pressure and saves space. */
1569 #define CONDITIONAL_ATTACH(src) { \
1570 void *entry = _mesa_hash_table_u64_search(ctx->ssa_constants, alu->ssa_args.src + 1); \
1573 attach_constants(ctx, alu, entry, alu->ssa_args.src + 1); \
1574 alu->ssa_args.src = SSA_FIXED_REGISTER(REGISTER_CONSTANT); \
1579 inline_alu_constants(compiler_context
*ctx
)
1581 mir_foreach_instr(ctx
, alu
) {
1582 /* Other instructions cannot inline constants */
1583 if (alu
->type
!= TAG_ALU_4
) continue;
1585 /* If there is already a constant here, we can do nothing */
1586 if (alu
->has_constants
) continue;
1588 /* It makes no sense to inline constants on a branch */
1589 if (alu
->compact_branch
|| alu
->prepacked_branch
) continue;
1591 CONDITIONAL_ATTACH(src0
);
1593 if (!alu
->has_constants
) {
1594 CONDITIONAL_ATTACH(src1
)
1595 } else if (!alu
->inline_constant
) {
1596 /* Corner case: _two_ vec4 constants, for instance with a
1597 * csel. For this case, we can only use a constant
1598 * register for one, we'll have to emit a move for the
1599 * other. Note, if both arguments are constants, then
1600 * necessarily neither argument depends on the value of
1601 * any particular register. As the destination register
1602 * will be wiped, that means we can spill the constant
1603 * to the destination register.
1606 void *entry
= _mesa_hash_table_u64_search(ctx
->ssa_constants
, alu
->ssa_args
.src1
+ 1);
1607 unsigned scratch
= alu
->ssa_args
.dest
;
1610 midgard_instruction ins
= v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT
), blank_alu_src
, scratch
);
1611 attach_constants(ctx
, &ins
, entry
, alu
->ssa_args
.src1
+ 1);
1613 /* Force a break XXX Defer r31 writes */
1614 ins
.unit
= UNIT_VLUT
;
1616 /* Set the source */
1617 alu
->ssa_args
.src1
= scratch
;
1619 /* Inject us -before- the last instruction which set r31 */
1620 mir_insert_instruction_before(mir_prev_op(alu
), ins
);
1626 /* Midgard supports two types of constants, embedded constants (128-bit) and
1627 * inline constants (16-bit). Sometimes, especially with scalar ops, embedded
1628 * constants can be demoted to inline constants, for space savings and
1629 * sometimes a performance boost */
1632 embedded_to_inline_constant(compiler_context
*ctx
)
1634 mir_foreach_instr(ctx
, ins
) {
1635 if (!ins
->has_constants
) continue;
1637 if (ins
->ssa_args
.inline_constant
) continue;
1639 /* Blend constants must not be inlined by definition */
1640 if (ins
->has_blend_constant
) continue;
1642 /* src1 cannot be an inline constant due to encoding
1643 * restrictions. So, if possible we try to flip the arguments
1646 int op
= ins
->alu
.op
;
1648 if (ins
->ssa_args
.src0
== SSA_FIXED_REGISTER(REGISTER_CONSTANT
)) {
1650 /* These ops require an operational change to flip
1651 * their arguments TODO */
1652 case midgard_alu_op_flt
:
1653 case midgard_alu_op_fle
:
1654 case midgard_alu_op_ilt
:
1655 case midgard_alu_op_ile
:
1656 case midgard_alu_op_fcsel
:
1657 case midgard_alu_op_icsel
:
1658 DBG("Missed non-commutative flip (%s)\n", alu_opcode_props
[op
].name
);
1663 if (alu_opcode_props
[op
].props
& OP_COMMUTES
) {
1664 /* Flip the SSA numbers */
1665 ins
->ssa_args
.src0
= ins
->ssa_args
.src1
;
1666 ins
->ssa_args
.src1
= SSA_FIXED_REGISTER(REGISTER_CONSTANT
);
1668 /* And flip the modifiers */
1672 src_temp
= ins
->alu
.src2
;
1673 ins
->alu
.src2
= ins
->alu
.src1
;
1674 ins
->alu
.src1
= src_temp
;
1678 if (ins
->ssa_args
.src1
== SSA_FIXED_REGISTER(REGISTER_CONSTANT
)) {
1679 /* Extract the source information */
1681 midgard_vector_alu_src
*src
;
1682 int q
= ins
->alu
.src2
;
1683 midgard_vector_alu_src
*m
= (midgard_vector_alu_src
*) &q
;
1686 /* Component is from the swizzle, e.g. r26.w -> w component. TODO: What if x is masked out? */
1687 int component
= src
->swizzle
& 3;
1689 /* Scale constant appropriately, if we can legally */
1690 uint16_t scaled_constant
= 0;
1692 if (midgard_is_integer_op(op
)) {
1693 unsigned int *iconstants
= (unsigned int *) ins
->constants
;
1694 scaled_constant
= (uint16_t) iconstants
[component
];
1696 /* Constant overflow after resize */
1697 if (scaled_constant
!= iconstants
[component
])
1700 float original
= (float) ins
->constants
[component
];
1701 scaled_constant
= _mesa_float_to_half(original
);
1703 /* Check for loss of precision. If this is
1704 * mediump, we don't care, but for a highp
1705 * shader, we need to pay attention. NIR
1706 * doesn't yet tell us which mode we're in!
1707 * Practically this prevents most constants
1708 * from being inlined, sadly. */
1710 float fp32
= _mesa_half_to_float(scaled_constant
);
1712 if (fp32
!= original
)
1716 /* We don't know how to handle these with a constant */
1718 if (src
->mod
|| src
->half
|| src
->rep_low
|| src
->rep_high
) {
1719 DBG("Bailing inline constant...\n");
1723 /* Make sure that the constant is not itself a
1724 * vector by checking if all accessed values
1725 * (by the swizzle) are the same. */
1727 uint32_t *cons
= (uint32_t *) ins
->constants
;
1728 uint32_t value
= cons
[component
];
1730 bool is_vector
= false;
1731 unsigned mask
= effective_writemask(&ins
->alu
);
1733 for (int c
= 1; c
< 4; ++c
) {
1734 /* We only care if this component is actually used */
1735 if (!(mask
& (1 << c
)))
1738 uint32_t test
= cons
[(src
->swizzle
>> (2 * c
)) & 3];
1740 if (test
!= value
) {
1749 /* Get rid of the embedded constant */
1750 ins
->has_constants
= false;
1751 ins
->ssa_args
.src1
= SSA_UNUSED_0
;
1752 ins
->ssa_args
.inline_constant
= true;
1753 ins
->inline_constant
= scaled_constant
;
1758 /* Map normal SSA sources to other SSA sources / fixed registers (like
1762 map_ssa_to_alias(compiler_context
*ctx
, int *ref
)
1764 /* Sign is used quite deliberately for unused */
1768 unsigned int alias
= (uintptr_t) _mesa_hash_table_u64_search(ctx
->ssa_to_alias
, *ref
+ 1);
1771 /* Remove entry in leftovers to avoid a redunant fmov */
1773 struct set_entry
*leftover
= _mesa_set_search(ctx
->leftover_ssa_to_alias
, ((void *) (uintptr_t) (*ref
+ 1)));
1776 _mesa_set_remove(ctx
->leftover_ssa_to_alias
, leftover
);
1778 /* Assign the alias map */
1784 /* Basic dead code elimination on the MIR itself, which cleans up e.g. the
1785 * texture pipeline */
1788 midgard_opt_dead_code_eliminate(compiler_context
*ctx
, midgard_block
*block
)
1790 bool progress
= false;
1792 mir_foreach_instr_in_block_safe(block
, ins
) {
1793 if (ins
->type
!= TAG_ALU_4
) continue;
1794 if (ins
->compact_branch
) continue;
1796 if (ins
->ssa_args
.dest
>= SSA_FIXED_MINIMUM
) continue;
1797 if (mir_is_live_after(ctx
, block
, ins
, ins
->ssa_args
.dest
)) continue;
1799 mir_remove_instruction(ins
);
1806 /* Dead code elimination for branches at the end of a block - only one branch
1807 * per block is legal semantically */
1810 midgard_opt_cull_dead_branch(compiler_context
*ctx
, midgard_block
*block
)
1812 bool branched
= false;
1814 mir_foreach_instr_in_block_safe(block
, ins
) {
1815 if (!midgard_is_branch_unit(ins
->unit
)) continue;
1817 /* We ignore prepacked branches since the fragment epilogue is
1818 * just generally special */
1819 if (ins
->prepacked_branch
) continue;
1821 /* Discards are similarly special and may not correspond to the
1824 if (ins
->branch
.target_type
== TARGET_DISCARD
) continue;
1827 /* We already branched, so this is dead */
1828 mir_remove_instruction(ins
);
1836 mir_nontrivial_mod(midgard_vector_alu_src src
, bool is_int
, unsigned mask
)
1839 if (!is_int
&& src
.mod
) return true;
1842 for (unsigned c
= 0; c
< 4; ++c
) {
1843 if (!(mask
& (1 << c
))) continue;
1844 if (((src
.swizzle
>> (2*c
)) & 3) != c
) return true;
1851 mir_nontrivial_source2_mod(midgard_instruction
*ins
)
1853 unsigned mask
= squeeze_writemask(ins
->alu
.mask
);
1854 bool is_int
= midgard_is_integer_op(ins
->alu
.op
);
1856 midgard_vector_alu_src src2
=
1857 vector_alu_from_unsigned(ins
->alu
.src2
);
1859 return mir_nontrivial_mod(src2
, is_int
, mask
);
1863 mir_nontrivial_outmod(midgard_instruction
*ins
)
1865 bool is_int
= midgard_is_integer_op(ins
->alu
.op
);
1866 unsigned mod
= ins
->alu
.outmod
;
1869 return mod
!= midgard_outmod_int_wrap
;
1871 return mod
!= midgard_outmod_none
;
1875 midgard_opt_copy_prop(compiler_context
*ctx
, midgard_block
*block
)
1877 bool progress
= false;
1879 mir_foreach_instr_in_block_safe(block
, ins
) {
1880 if (ins
->type
!= TAG_ALU_4
) continue;
1881 if (!OP_IS_MOVE(ins
->alu
.op
)) continue;
1883 unsigned from
= ins
->ssa_args
.src1
;
1884 unsigned to
= ins
->ssa_args
.dest
;
1886 /* We only work on pure SSA */
1888 if (to
>= SSA_FIXED_MINIMUM
) continue;
1889 if (from
>= SSA_FIXED_MINIMUM
) continue;
1890 if (to
>= ctx
->func
->impl
->ssa_alloc
) continue;
1891 if (from
>= ctx
->func
->impl
->ssa_alloc
) continue;
1893 /* Constant propagation is not handled here, either */
1894 if (ins
->ssa_args
.inline_constant
) continue;
1895 if (ins
->has_constants
) continue;
1897 if (mir_nontrivial_source2_mod(ins
)) continue;
1898 if (mir_nontrivial_outmod(ins
)) continue;
1900 /* We're clear -- rewrite */
1901 mir_rewrite_index_src(ctx
, to
, from
);
1902 mir_remove_instruction(ins
);
1909 /* fmov.pos is an idiom for fpos. Propoagate the .pos up to the source, so then
1910 * the move can be propagated away entirely */
1913 mir_compose_float_outmod(midgard_outmod_float
*outmod
, midgard_outmod_float comp
)
1916 if (comp
== midgard_outmod_none
)
1919 if (*outmod
== midgard_outmod_none
) {
1924 /* TODO: Compose rules */
1929 midgard_opt_pos_propagate(compiler_context
*ctx
, midgard_block
*block
)
1931 bool progress
= false;
1933 mir_foreach_instr_in_block_safe(block
, ins
) {
1934 if (ins
->type
!= TAG_ALU_4
) continue;
1935 if (ins
->alu
.op
!= midgard_alu_op_fmov
) continue;
1936 if (ins
->alu
.outmod
!= midgard_outmod_pos
) continue;
1938 /* TODO: Registers? */
1939 unsigned src
= ins
->ssa_args
.src1
;
1940 if (src
>= ctx
->func
->impl
->ssa_alloc
) continue;
1941 assert(!mir_has_multiple_writes(ctx
, src
));
1943 /* There might be a source modifier, too */
1944 if (mir_nontrivial_source2_mod(ins
)) continue;
1946 /* Backpropagate the modifier */
1947 mir_foreach_instr_in_block_from_rev(block
, v
, mir_prev_op(ins
)) {
1948 if (v
->type
!= TAG_ALU_4
) continue;
1949 if (v
->ssa_args
.dest
!= src
) continue;
1951 /* Can we even take a float outmod? */
1952 if (midgard_is_integer_out_op(v
->alu
.op
)) continue;
1954 midgard_outmod_float temp
= v
->alu
.outmod
;
1955 progress
|= mir_compose_float_outmod(&temp
, ins
->alu
.outmod
);
1957 /* Throw in the towel.. */
1958 if (!progress
) break;
1960 /* Otherwise, transfer the modifier */
1961 v
->alu
.outmod
= temp
;
1962 ins
->alu
.outmod
= midgard_outmod_none
;
1972 midgard_opt_copy_prop_tex(compiler_context
*ctx
, midgard_block
*block
)
1974 bool progress
= false;
1976 mir_foreach_instr_in_block_safe(block
, ins
) {
1977 if (ins
->type
!= TAG_ALU_4
) continue;
1978 if (!OP_IS_MOVE(ins
->alu
.op
)) continue;
1980 unsigned from
= ins
->ssa_args
.src1
;
1981 unsigned to
= ins
->ssa_args
.dest
;
1983 /* Make sure it's simple enough for us to handle */
1985 if (from
>= SSA_FIXED_MINIMUM
) continue;
1986 if (from
>= ctx
->func
->impl
->ssa_alloc
) continue;
1987 if (to
< SSA_FIXED_REGISTER(REGISTER_TEXTURE_BASE
)) continue;
1988 if (to
> SSA_FIXED_REGISTER(REGISTER_TEXTURE_BASE
+ 1)) continue;
1990 bool eliminated
= false;
1992 mir_foreach_instr_in_block_from_rev(block
, v
, mir_prev_op(ins
)) {
1993 /* The texture registers are not SSA so be careful.
1994 * Conservatively, just stop if we hit a texture op
1995 * (even if it may not write) to where we are */
1997 if (v
->type
!= TAG_ALU_4
)
2000 if (v
->ssa_args
.dest
== from
) {
2001 /* We don't want to track partial writes ... */
2002 if (v
->alu
.mask
== 0xF) {
2003 v
->ssa_args
.dest
= to
;
2012 mir_remove_instruction(ins
);
2014 progress
|= eliminated
;
2020 /* The following passes reorder MIR instructions to enable better scheduling */
2023 midgard_pair_load_store(compiler_context
*ctx
, midgard_block
*block
)
2025 mir_foreach_instr_in_block_safe(block
, ins
) {
2026 if (ins
->type
!= TAG_LOAD_STORE_4
) continue;
2028 /* We've found a load/store op. Check if next is also load/store. */
2029 midgard_instruction
*next_op
= mir_next_op(ins
);
2030 if (&next_op
->link
!= &block
->instructions
) {
2031 if (next_op
->type
== TAG_LOAD_STORE_4
) {
2032 /* If so, we're done since we're a pair */
2033 ins
= mir_next_op(ins
);
2037 /* Maximum search distance to pair, to avoid register pressure disasters */
2038 int search_distance
= 8;
2040 /* Otherwise, we have an orphaned load/store -- search for another load */
2041 mir_foreach_instr_in_block_from(block
, c
, mir_next_op(ins
)) {
2042 /* Terminate search if necessary */
2043 if (!(search_distance
--)) break;
2045 if (c
->type
!= TAG_LOAD_STORE_4
) continue;
2047 /* Stores cannot be reordered, since they have
2048 * dependencies. For the same reason, indirect
2049 * loads cannot be reordered as their index is
2050 * loaded in r27.w */
2052 if (OP_IS_STORE(c
->load_store
.op
)) continue;
2054 /* It appears the 0x800 bit is set whenever a
2055 * load is direct, unset when it is indirect.
2056 * Skip indirect loads. */
2058 if (!(c
->load_store
.unknown
& 0x800)) continue;
2060 /* We found one! Move it up to pair and remove it from the old location */
2062 mir_insert_instruction_before(ins
, *c
);
2063 mir_remove_instruction(c
);
2071 /* If there are leftovers after the below pass, emit actual fmov
2072 * instructions for the slow-but-correct path */
2075 emit_leftover_move(compiler_context
*ctx
)
2077 set_foreach(ctx
->leftover_ssa_to_alias
, leftover
) {
2078 int base
= ((uintptr_t) leftover
->key
) - 1;
2081 map_ssa_to_alias(ctx
, &mapped
);
2082 EMIT(mov
, mapped
, blank_alu_src
, base
);
2087 actualise_ssa_to_alias(compiler_context
*ctx
)
2089 mir_foreach_instr(ctx
, ins
) {
2090 map_ssa_to_alias(ctx
, &ins
->ssa_args
.src0
);
2091 map_ssa_to_alias(ctx
, &ins
->ssa_args
.src1
);
2094 emit_leftover_move(ctx
);
2098 emit_fragment_epilogue(compiler_context
*ctx
)
2100 /* Special case: writing out constants requires us to include the move
2101 * explicitly now, so shove it into r0 */
2103 void *constant_value
= _mesa_hash_table_u64_search(ctx
->ssa_constants
, ctx
->fragment_output
+ 1);
2105 if (constant_value
) {
2106 midgard_instruction ins
= v_mov(SSA_FIXED_REGISTER(REGISTER_CONSTANT
), blank_alu_src
, SSA_FIXED_REGISTER(0));
2107 attach_constants(ctx
, &ins
, constant_value
, ctx
->fragment_output
+ 1);
2108 emit_mir_instruction(ctx
, ins
);
2111 /* Perform the actual fragment writeout. We have two writeout/branch
2112 * instructions, forming a loop until writeout is successful as per the
2113 * docs. TODO: gl_FragDepth */
2115 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, 0, midgard_condition_always
);
2116 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, -1, midgard_condition_always
);
2119 /* For the blend epilogue, we need to convert the blended fragment vec4 (stored
2120 * in r0) to a RGBA8888 value by scaling and type converting. We then output it
2121 * with the int8 analogue to the fragment epilogue */
2124 emit_blend_epilogue(compiler_context
*ctx
)
2126 /* vmul.fmul.none.fulllow hr48, r0, #255 */
2128 midgard_instruction scale
= {
2131 .inline_constant
= _mesa_float_to_half(255.0),
2133 .src0
= SSA_FIXED_REGISTER(0),
2134 .src1
= SSA_UNUSED_0
,
2135 .dest
= SSA_FIXED_REGISTER(24),
2136 .inline_constant
= true
2139 .op
= midgard_alu_op_fmul
,
2140 .reg_mode
= midgard_reg_mode_32
,
2141 .dest_override
= midgard_dest_override_lower
,
2143 .src1
= vector_alu_srco_unsigned(blank_alu_src
),
2144 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
2148 emit_mir_instruction(ctx
, scale
);
2150 /* vadd.f2u_rte.pos.low hr0, hr48, #0 */
2152 midgard_vector_alu_src alu_src
= blank_alu_src
;
2153 alu_src
.half
= true;
2155 midgard_instruction f2u_rte
= {
2158 .src0
= SSA_FIXED_REGISTER(24),
2159 .src1
= SSA_UNUSED_0
,
2160 .dest
= SSA_FIXED_REGISTER(0),
2161 .inline_constant
= true
2164 .op
= midgard_alu_op_f2u_rte
,
2165 .reg_mode
= midgard_reg_mode_16
,
2166 .dest_override
= midgard_dest_override_lower
,
2167 .outmod
= midgard_outmod_pos
,
2169 .src1
= vector_alu_srco_unsigned(alu_src
),
2170 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
2174 emit_mir_instruction(ctx
, f2u_rte
);
2176 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, 0, midgard_condition_always
);
2177 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, -1, midgard_condition_always
);
2180 static midgard_block
*
2181 emit_block(compiler_context
*ctx
, nir_block
*block
)
2183 midgard_block
*this_block
= calloc(sizeof(midgard_block
), 1);
2184 list_addtail(&this_block
->link
, &ctx
->blocks
);
2186 this_block
->is_scheduled
= false;
2189 ctx
->texture_index
[0] = -1;
2190 ctx
->texture_index
[1] = -1;
2192 /* Add us as a successor to the block we are following */
2193 if (ctx
->current_block
)
2194 midgard_block_add_successor(ctx
->current_block
, this_block
);
2196 /* Set up current block */
2197 list_inithead(&this_block
->instructions
);
2198 ctx
->current_block
= this_block
;
2200 nir_foreach_instr(instr
, block
) {
2201 emit_instr(ctx
, instr
);
2202 ++ctx
->instruction_count
;
2205 inline_alu_constants(ctx
);
2206 embedded_to_inline_constant(ctx
);
2208 /* Perform heavylifting for aliasing */
2209 actualise_ssa_to_alias(ctx
);
2211 midgard_pair_load_store(ctx
, this_block
);
2213 /* Append fragment shader epilogue (value writeout) */
2214 if (ctx
->stage
== MESA_SHADER_FRAGMENT
) {
2215 if (block
== nir_impl_last_block(ctx
->func
->impl
)) {
2217 emit_blend_epilogue(ctx
);
2219 emit_fragment_epilogue(ctx
);
2223 if (block
== nir_start_block(ctx
->func
->impl
))
2224 ctx
->initial_block
= this_block
;
2226 if (block
== nir_impl_last_block(ctx
->func
->impl
))
2227 ctx
->final_block
= this_block
;
2229 /* Allow the next control flow to access us retroactively, for
2231 ctx
->current_block
= this_block
;
2233 /* Document the fallthrough chain */
2234 ctx
->previous_source_block
= this_block
;
2239 static midgard_block
*emit_cf_list(struct compiler_context
*ctx
, struct exec_list
*list
);
2242 emit_if(struct compiler_context
*ctx
, nir_if
*nif
)
2244 /* Conditional branches expect the condition in r31.w; emit a move for
2245 * that in the _previous_ block (which is the current block). */
2246 emit_condition(ctx
, &nif
->condition
, true, COMPONENT_X
);
2248 /* Speculatively emit the branch, but we can't fill it in until later */
2249 EMIT(branch
, true, true);
2250 midgard_instruction
*then_branch
= mir_last_in_block(ctx
->current_block
);
2252 /* Emit the two subblocks */
2253 midgard_block
*then_block
= emit_cf_list(ctx
, &nif
->then_list
);
2255 /* Emit a jump from the end of the then block to the end of the else */
2256 EMIT(branch
, false, false);
2257 midgard_instruction
*then_exit
= mir_last_in_block(ctx
->current_block
);
2259 /* Emit second block, and check if it's empty */
2261 int else_idx
= ctx
->block_count
;
2262 int count_in
= ctx
->instruction_count
;
2263 midgard_block
*else_block
= emit_cf_list(ctx
, &nif
->else_list
);
2264 int after_else_idx
= ctx
->block_count
;
2266 /* Now that we have the subblocks emitted, fix up the branches */
2271 if (ctx
->instruction_count
== count_in
) {
2272 /* The else block is empty, so don't emit an exit jump */
2273 mir_remove_instruction(then_exit
);
2274 then_branch
->branch
.target_block
= after_else_idx
;
2276 then_branch
->branch
.target_block
= else_idx
;
2277 then_exit
->branch
.target_block
= after_else_idx
;
2282 emit_loop(struct compiler_context
*ctx
, nir_loop
*nloop
)
2284 /* Remember where we are */
2285 midgard_block
*start_block
= ctx
->current_block
;
2287 /* Allocate a loop number, growing the current inner loop depth */
2288 int loop_idx
= ++ctx
->current_loop_depth
;
2290 /* Get index from before the body so we can loop back later */
2291 int start_idx
= ctx
->block_count
;
2293 /* Emit the body itself */
2294 emit_cf_list(ctx
, &nloop
->body
);
2296 /* Branch back to loop back */
2297 struct midgard_instruction br_back
= v_branch(false, false);
2298 br_back
.branch
.target_block
= start_idx
;
2299 emit_mir_instruction(ctx
, br_back
);
2301 /* Mark down that branch in the graph. Note that we're really branching
2302 * to the block *after* we started in. TODO: Why doesn't the branch
2303 * itself have an off-by-one then...? */
2304 midgard_block_add_successor(ctx
->current_block
, start_block
->successors
[0]);
2306 /* Find the index of the block about to follow us (note: we don't add
2307 * one; blocks are 0-indexed so we get a fencepost problem) */
2308 int break_block_idx
= ctx
->block_count
;
2310 /* Fix up the break statements we emitted to point to the right place,
2311 * now that we can allocate a block number for them */
2313 list_for_each_entry_from(struct midgard_block
, block
, start_block
, &ctx
->blocks
, link
) {
2314 mir_foreach_instr_in_block(block
, ins
) {
2315 if (ins
->type
!= TAG_ALU_4
) continue;
2316 if (!ins
->compact_branch
) continue;
2317 if (ins
->prepacked_branch
) continue;
2319 /* We found a branch -- check the type to see if we need to do anything */
2320 if (ins
->branch
.target_type
!= TARGET_BREAK
) continue;
2322 /* It's a break! Check if it's our break */
2323 if (ins
->branch
.target_break
!= loop_idx
) continue;
2325 /* Okay, cool, we're breaking out of this loop.
2326 * Rewrite from a break to a goto */
2328 ins
->branch
.target_type
= TARGET_GOTO
;
2329 ins
->branch
.target_block
= break_block_idx
;
2333 /* Now that we've finished emitting the loop, free up the depth again
2334 * so we play nice with recursion amid nested loops */
2335 --ctx
->current_loop_depth
;
2338 static midgard_block
*
2339 emit_cf_list(struct compiler_context
*ctx
, struct exec_list
*list
)
2341 midgard_block
*start_block
= NULL
;
2343 foreach_list_typed(nir_cf_node
, node
, node
, list
) {
2344 switch (node
->type
) {
2345 case nir_cf_node_block
: {
2346 midgard_block
*block
= emit_block(ctx
, nir_cf_node_as_block(node
));
2349 start_block
= block
;
2354 case nir_cf_node_if
:
2355 emit_if(ctx
, nir_cf_node_as_if(node
));
2358 case nir_cf_node_loop
:
2359 emit_loop(ctx
, nir_cf_node_as_loop(node
));
2362 case nir_cf_node_function
:
2371 /* Due to lookahead, we need to report the first tag executed in the command
2372 * stream and in branch targets. An initial block might be empty, so iterate
2373 * until we find one that 'works' */
2376 midgard_get_first_tag_from_block(compiler_context
*ctx
, unsigned block_idx
)
2378 midgard_block
*initial_block
= mir_get_block(ctx
, block_idx
);
2380 unsigned first_tag
= 0;
2383 midgard_bundle
*initial_bundle
= util_dynarray_element(&initial_block
->bundles
, midgard_bundle
, 0);
2385 if (initial_bundle
) {
2386 first_tag
= initial_bundle
->tag
;
2390 /* Initial block is empty, try the next block */
2391 initial_block
= list_first_entry(&(initial_block
->link
), midgard_block
, link
);
2392 } while(initial_block
!= NULL
);
2399 midgard_compile_shader_nir(nir_shader
*nir
, midgard_program
*program
, bool is_blend
)
2401 struct util_dynarray
*compiled
= &program
->compiled
;
2403 midgard_debug
= debug_get_option_midgard_debug();
2405 compiler_context ictx
= {
2407 .stage
= nir
->info
.stage
,
2409 .is_blend
= is_blend
,
2410 .blend_constant_offset
= -1,
2412 .alpha_ref
= program
->alpha_ref
2415 compiler_context
*ctx
= &ictx
;
2417 /* TODO: Decide this at runtime */
2418 ctx
->uniform_cutoff
= 8;
2420 /* Initialize at a global (not block) level hash tables */
2422 ctx
->ssa_constants
= _mesa_hash_table_u64_create(NULL
);
2423 ctx
->ssa_to_alias
= _mesa_hash_table_u64_create(NULL
);
2424 ctx
->hash_to_temp
= _mesa_hash_table_u64_create(NULL
);
2425 ctx
->sysval_to_id
= _mesa_hash_table_u64_create(NULL
);
2426 ctx
->leftover_ssa_to_alias
= _mesa_set_create(NULL
, _mesa_hash_pointer
, _mesa_key_pointer_equal
);
2428 /* Record the varying mapping for the command stream's bookkeeping */
2430 struct exec_list
*varyings
=
2431 ctx
->stage
== MESA_SHADER_VERTEX
? &nir
->outputs
: &nir
->inputs
;
2433 unsigned max_varying
= 0;
2434 nir_foreach_variable(var
, varyings
) {
2435 unsigned loc
= var
->data
.driver_location
;
2436 unsigned sz
= glsl_type_size(var
->type
, FALSE
);
2438 for (int c
= 0; c
< sz
; ++c
) {
2439 program
->varyings
[loc
+ c
] = var
->data
.location
+ c
;
2440 max_varying
= MAX2(max_varying
, loc
+ c
);
2444 /* Lower gl_Position pre-optimisation, but after lowering vars to ssa
2445 * (so we don't accidentally duplicate the epilogue since mesa/st has
2446 * messed with our I/O quite a bit already) */
2448 NIR_PASS_V(nir
, nir_lower_vars_to_ssa
);
2450 if (ctx
->stage
== MESA_SHADER_VERTEX
)
2451 NIR_PASS_V(nir
, nir_lower_viewport_transform
);
2453 NIR_PASS_V(nir
, nir_lower_var_copies
);
2454 NIR_PASS_V(nir
, nir_lower_vars_to_ssa
);
2455 NIR_PASS_V(nir
, nir_split_var_copies
);
2456 NIR_PASS_V(nir
, nir_lower_var_copies
);
2457 NIR_PASS_V(nir
, nir_lower_global_vars_to_local
);
2458 NIR_PASS_V(nir
, nir_lower_var_copies
);
2459 NIR_PASS_V(nir
, nir_lower_vars_to_ssa
);
2461 NIR_PASS_V(nir
, nir_lower_io
, nir_var_all
, glsl_type_size
, 0);
2463 /* Optimisation passes */
2467 if (midgard_debug
& MIDGARD_DBG_SHADERS
) {
2468 nir_print_shader(nir
, stdout
);
2471 /* Assign sysvals and counts, now that we're sure
2472 * (post-optimisation) */
2474 midgard_nir_assign_sysvals(ctx
, nir
);
2476 program
->uniform_count
= nir
->num_uniforms
;
2477 program
->sysval_count
= ctx
->sysval_count
;
2478 memcpy(program
->sysvals
, ctx
->sysvals
, sizeof(ctx
->sysvals
[0]) * ctx
->sysval_count
);
2480 program
->attribute_count
= (ctx
->stage
== MESA_SHADER_VERTEX
) ? nir
->num_inputs
: 0;
2481 program
->varying_count
= max_varying
+ 1; /* Fencepost off-by-one */
2483 nir_foreach_function(func
, nir
) {
2487 list_inithead(&ctx
->blocks
);
2488 ctx
->block_count
= 0;
2491 emit_cf_list(ctx
, &func
->impl
->body
);
2492 emit_block(ctx
, func
->impl
->end_block
);
2494 break; /* TODO: Multi-function shaders */
2497 util_dynarray_init(compiled
, NULL
);
2499 /* MIR-level optimizations */
2501 bool progress
= false;
2506 mir_foreach_block(ctx
, block
) {
2507 progress
|= midgard_opt_pos_propagate(ctx
, block
);
2508 progress
|= midgard_opt_copy_prop(ctx
, block
);
2509 progress
|= midgard_opt_copy_prop_tex(ctx
, block
);
2510 progress
|= midgard_opt_dead_code_eliminate(ctx
, block
);
2514 /* Nested control-flow can result in dead branches at the end of the
2515 * block. This messes with our analysis and is just dead code, so cull
2517 mir_foreach_block(ctx
, block
) {
2518 midgard_opt_cull_dead_branch(ctx
, block
);
2522 schedule_program(ctx
);
2524 /* Now that all the bundles are scheduled and we can calculate block
2525 * sizes, emit actual branch instructions rather than placeholders */
2527 int br_block_idx
= 0;
2529 mir_foreach_block(ctx
, block
) {
2530 util_dynarray_foreach(&block
->bundles
, midgard_bundle
, bundle
) {
2531 for (int c
= 0; c
< bundle
->instruction_count
; ++c
) {
2532 midgard_instruction
*ins
= bundle
->instructions
[c
];
2534 if (!midgard_is_branch_unit(ins
->unit
)) continue;
2536 if (ins
->prepacked_branch
) continue;
2538 /* Parse some basic branch info */
2539 bool is_compact
= ins
->unit
== ALU_ENAB_BR_COMPACT
;
2540 bool is_conditional
= ins
->branch
.conditional
;
2541 bool is_inverted
= ins
->branch
.invert_conditional
;
2542 bool is_discard
= ins
->branch
.target_type
== TARGET_DISCARD
;
2544 /* Determine the block we're jumping to */
2545 int target_number
= ins
->branch
.target_block
;
2547 /* Report the destination tag */
2548 int dest_tag
= is_discard
? 0 : midgard_get_first_tag_from_block(ctx
, target_number
);
2550 /* Count up the number of quadwords we're
2551 * jumping over = number of quadwords until
2552 * (br_block_idx, target_number) */
2554 int quadword_offset
= 0;
2557 /* Jump to the end of the shader. We
2558 * need to include not only the
2559 * following blocks, but also the
2560 * contents of our current block (since
2561 * discard can come in the middle of
2564 midgard_block
*blk
= mir_get_block(ctx
, br_block_idx
+ 1);
2566 for (midgard_bundle
*bun
= bundle
+ 1; bun
< (midgard_bundle
*)((char*) block
->bundles
.data
+ block
->bundles
.size
); ++bun
) {
2567 quadword_offset
+= quadword_size(bun
->tag
);
2570 mir_foreach_block_from(ctx
, blk
, b
) {
2571 quadword_offset
+= b
->quadword_count
;
2574 } else if (target_number
> br_block_idx
) {
2577 for (int idx
= br_block_idx
+ 1; idx
< target_number
; ++idx
) {
2578 midgard_block
*blk
= mir_get_block(ctx
, idx
);
2581 quadword_offset
+= blk
->quadword_count
;
2584 /* Jump backwards */
2586 for (int idx
= br_block_idx
; idx
>= target_number
; --idx
) {
2587 midgard_block
*blk
= mir_get_block(ctx
, idx
);
2590 quadword_offset
-= blk
->quadword_count
;
2594 /* Unconditional extended branches (far jumps)
2595 * have issues, so we always use a conditional
2596 * branch, setting the condition to always for
2597 * unconditional. For compact unconditional
2598 * branches, cond isn't used so it doesn't
2599 * matter what we pick. */
2601 midgard_condition cond
=
2602 !is_conditional
? midgard_condition_always
:
2603 is_inverted
? midgard_condition_false
:
2604 midgard_condition_true
;
2606 midgard_jmp_writeout_op op
=
2607 is_discard
? midgard_jmp_writeout_op_discard
:
2608 (is_compact
&& !is_conditional
) ? midgard_jmp_writeout_op_branch_uncond
:
2609 midgard_jmp_writeout_op_branch_cond
;
2612 midgard_branch_extended branch
=
2613 midgard_create_branch_extended(
2618 memcpy(&ins
->branch_extended
, &branch
, sizeof(branch
));
2619 } else if (is_conditional
|| is_discard
) {
2620 midgard_branch_cond branch
= {
2622 .dest_tag
= dest_tag
,
2623 .offset
= quadword_offset
,
2627 assert(branch
.offset
== quadword_offset
);
2629 memcpy(&ins
->br_compact
, &branch
, sizeof(branch
));
2631 assert(op
== midgard_jmp_writeout_op_branch_uncond
);
2633 midgard_branch_uncond branch
= {
2635 .dest_tag
= dest_tag
,
2636 .offset
= quadword_offset
,
2640 assert(branch
.offset
== quadword_offset
);
2642 memcpy(&ins
->br_compact
, &branch
, sizeof(branch
));
2650 /* Emit flat binary from the instruction arrays. Iterate each block in
2651 * sequence. Save instruction boundaries such that lookahead tags can
2652 * be assigned easily */
2654 /* Cache _all_ bundles in source order for lookahead across failed branches */
2656 int bundle_count
= 0;
2657 mir_foreach_block(ctx
, block
) {
2658 bundle_count
+= block
->bundles
.size
/ sizeof(midgard_bundle
);
2660 midgard_bundle
**source_order_bundles
= malloc(sizeof(midgard_bundle
*) * bundle_count
);
2662 mir_foreach_block(ctx
, block
) {
2663 util_dynarray_foreach(&block
->bundles
, midgard_bundle
, bundle
) {
2664 source_order_bundles
[bundle_idx
++] = bundle
;
2668 int current_bundle
= 0;
2670 /* Midgard prefetches instruction types, so during emission we
2671 * need to lookahead. Unless this is the last instruction, in
2672 * which we return 1. Or if this is the second to last and the
2673 * last is an ALU, then it's also 1... */
2675 mir_foreach_block(ctx
, block
) {
2676 mir_foreach_bundle_in_block(block
, bundle
) {
2679 if (current_bundle
+ 1 < bundle_count
) {
2680 uint8_t next
= source_order_bundles
[current_bundle
+ 1]->tag
;
2682 if (!(current_bundle
+ 2 < bundle_count
) && IS_ALU(next
)) {
2689 emit_binary_bundle(ctx
, bundle
, compiled
, lookahead
);
2693 /* TODO: Free deeper */
2694 //util_dynarray_fini(&block->instructions);
2697 free(source_order_bundles
);
2699 /* Report the very first tag executed */
2700 program
->first_tag
= midgard_get_first_tag_from_block(ctx
, 0);
2702 /* Deal with off-by-one related to the fencepost problem */
2703 program
->work_register_count
= ctx
->work_registers
+ 1;
2705 program
->can_discard
= ctx
->can_discard
;
2706 program
->uniform_cutoff
= ctx
->uniform_cutoff
;
2708 program
->blend_patch_offset
= ctx
->blend_constant_offset
;
2710 if (midgard_debug
& MIDGARD_DBG_SHADERS
)
2711 disassemble_midgard(program
->compiled
.data
, program
->compiled
.size
);