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_XYZW SWIZZLE(COMPONENT_X, COMPONENT_Y, COMPONENT_Z, COMPONENT_W)
87 #define M_LOAD_STORE(name, rname, uname) \
88 static midgard_instruction m_##name(unsigned ssa, unsigned address) { \
89 midgard_instruction i = { \
90 .type = TAG_LOAD_STORE_4, \
97 .op = midgard_op_##name, \
99 .swizzle = SWIZZLE_XYZW, \
107 #define M_LOAD(name) M_LOAD_STORE(name, dest, src0)
108 #define M_STORE(name) M_LOAD_STORE(name, src0, dest)
110 const midgard_vector_alu_src blank_alu_src
= {
111 .swizzle
= SWIZZLE(COMPONENT_X
, COMPONENT_Y
, COMPONENT_Z
, COMPONENT_W
),
114 const midgard_vector_alu_src blank_alu_src_xxxx
= {
115 .swizzle
= SWIZZLE(COMPONENT_X
, COMPONENT_X
, COMPONENT_X
, COMPONENT_X
),
118 const midgard_scalar_alu_src blank_scalar_alu_src
= {
122 /* Used for encoding the unused source of 1-op instructions */
123 const midgard_vector_alu_src zero_alu_src
= { 0 };
125 /* Inputs a NIR ALU source, with modifiers attached if necessary, and outputs
126 * the corresponding Midgard source */
128 static midgard_vector_alu_src
129 vector_alu_modifiers(nir_alu_src
*src
, bool is_int
)
131 if (!src
) return blank_alu_src
;
133 midgard_vector_alu_src alu_src
= {
136 .half
= 0, /* TODO */
137 .swizzle
= SWIZZLE_FROM_ARRAY(src
->swizzle
)
141 /* TODO: sign-extend/zero-extend */
142 alu_src
.mod
= midgard_int_normal
;
144 /* These should have been lowered away */
145 assert(!(src
->abs
|| src
->negate
));
147 alu_src
.mod
= (src
->abs
<< 0) | (src
->negate
<< 1);
153 /* 'Intrinsic' move for misc aliasing uses independent of actual NIR ALU code */
155 static midgard_instruction
156 v_fmov(unsigned src
, midgard_vector_alu_src mod
, unsigned dest
)
158 midgard_instruction ins
= {
161 .src0
= SSA_UNUSED_1
,
166 .op
= midgard_alu_op_fmov
,
167 .reg_mode
= midgard_reg_mode_32
,
168 .dest_override
= midgard_dest_override_none
,
170 .src1
= vector_alu_srco_unsigned(zero_alu_src
),
171 .src2
= vector_alu_srco_unsigned(mod
)
178 /* load/store instructions have both 32-bit and 16-bit variants, depending on
179 * whether we are using vectors composed of highp or mediump. At the moment, we
180 * don't support half-floats -- this requires changes in other parts of the
181 * compiler -- therefore the 16-bit versions are commented out. */
183 //M_LOAD(ld_attr_16);
185 //M_LOAD(ld_vary_16);
187 //M_LOAD(ld_uniform_16);
188 M_LOAD(ld_uniform_32
);
189 M_LOAD(ld_color_buffer_8
);
190 //M_STORE(st_vary_16);
192 M_STORE(st_cubemap_coords
);
194 static midgard_instruction
195 v_alu_br_compact_cond(midgard_jmp_writeout_op op
, unsigned tag
, signed offset
, unsigned cond
)
197 midgard_branch_cond branch
= {
205 memcpy(&compact
, &branch
, sizeof(branch
));
207 midgard_instruction ins
= {
209 .unit
= ALU_ENAB_BR_COMPACT
,
210 .prepacked_branch
= true,
211 .compact_branch
= true,
212 .br_compact
= compact
215 if (op
== midgard_jmp_writeout_op_writeout
)
221 static midgard_instruction
222 v_branch(bool conditional
, bool invert
)
224 midgard_instruction ins
= {
226 .unit
= ALU_ENAB_BRANCH
,
227 .compact_branch
= true,
229 .conditional
= conditional
,
230 .invert_conditional
= invert
237 static midgard_branch_extended
238 midgard_create_branch_extended( midgard_condition cond
,
239 midgard_jmp_writeout_op op
,
241 signed quadword_offset
)
243 /* For unclear reasons, the condition code is repeated 8 times */
244 uint16_t duplicated_cond
=
254 midgard_branch_extended branch
= {
256 .dest_tag
= dest_tag
,
257 .offset
= quadword_offset
,
258 .cond
= duplicated_cond
265 attach_constants(compiler_context
*ctx
, midgard_instruction
*ins
, void *constants
, int name
)
267 ins
->has_constants
= true;
268 memcpy(&ins
->constants
, constants
, 16);
272 glsl_type_size(const struct glsl_type
*type
, bool bindless
)
274 return glsl_count_attribute_slots(type
, false);
277 /* Lower fdot2 to a vector multiplication followed by channel addition */
279 midgard_nir_lower_fdot2_body(nir_builder
*b
, nir_alu_instr
*alu
)
281 if (alu
->op
!= nir_op_fdot2
)
284 b
->cursor
= nir_before_instr(&alu
->instr
);
286 nir_ssa_def
*src0
= nir_ssa_for_alu_src(b
, alu
, 0);
287 nir_ssa_def
*src1
= nir_ssa_for_alu_src(b
, alu
, 1);
289 nir_ssa_def
*product
= nir_fmul(b
, src0
, src1
);
291 nir_ssa_def
*sum
= nir_fadd(b
,
292 nir_channel(b
, product
, 0),
293 nir_channel(b
, product
, 1));
295 /* Replace the fdot2 with this sum */
296 nir_ssa_def_rewrite_uses(&alu
->dest
.dest
.ssa
, nir_src_for_ssa(sum
));
300 midgard_nir_sysval_for_intrinsic(nir_intrinsic_instr
*instr
)
302 switch (instr
->intrinsic
) {
303 case nir_intrinsic_load_viewport_scale
:
304 return PAN_SYSVAL_VIEWPORT_SCALE
;
305 case nir_intrinsic_load_viewport_offset
:
306 return PAN_SYSVAL_VIEWPORT_OFFSET
;
313 midgard_nir_assign_sysval_body(compiler_context
*ctx
, nir_instr
*instr
)
317 if (instr
->type
== nir_instr_type_intrinsic
) {
318 nir_intrinsic_instr
*intr
= nir_instr_as_intrinsic(instr
);
319 sysval
= midgard_nir_sysval_for_intrinsic(intr
);
325 /* We have a sysval load; check if it's already been assigned */
327 if (_mesa_hash_table_u64_search(ctx
->sysval_to_id
, sysval
))
330 /* It hasn't -- so assign it now! */
332 unsigned id
= ctx
->sysval_count
++;
333 _mesa_hash_table_u64_insert(ctx
->sysval_to_id
, sysval
, (void *) ((uintptr_t) id
+ 1));
334 ctx
->sysvals
[id
] = sysval
;
338 midgard_nir_assign_sysvals(compiler_context
*ctx
, nir_shader
*shader
)
340 ctx
->sysval_count
= 0;
342 nir_foreach_function(function
, shader
) {
343 if (!function
->impl
) continue;
345 nir_foreach_block(block
, function
->impl
) {
346 nir_foreach_instr_safe(instr
, block
) {
347 midgard_nir_assign_sysval_body(ctx
, instr
);
354 midgard_nir_lower_fdot2(nir_shader
*shader
)
356 bool progress
= false;
358 nir_foreach_function(function
, shader
) {
359 if (!function
->impl
) continue;
362 nir_builder
*b
= &_b
;
363 nir_builder_init(b
, function
->impl
);
365 nir_foreach_block(block
, function
->impl
) {
366 nir_foreach_instr_safe(instr
, block
) {
367 if (instr
->type
!= nir_instr_type_alu
) continue;
369 nir_alu_instr
*alu
= nir_instr_as_alu(instr
);
370 midgard_nir_lower_fdot2_body(b
, alu
);
376 nir_metadata_preserve(function
->impl
, nir_metadata_block_index
| nir_metadata_dominance
);
384 optimise_nir(nir_shader
*nir
)
387 unsigned lower_flrp
=
388 (nir
->options
->lower_flrp16
? 16 : 0) |
389 (nir
->options
->lower_flrp32
? 32 : 0) |
390 (nir
->options
->lower_flrp64
? 64 : 0);
392 NIR_PASS(progress
, nir
, nir_lower_regs_to_ssa
);
393 NIR_PASS(progress
, nir
, midgard_nir_lower_fdot2
);
395 nir_lower_tex_options lower_tex_options
= {
399 NIR_PASS(progress
, nir
, nir_lower_tex
, &lower_tex_options
);
404 NIR_PASS(progress
, nir
, nir_lower_var_copies
);
405 NIR_PASS(progress
, nir
, nir_lower_vars_to_ssa
);
407 NIR_PASS(progress
, nir
, nir_copy_prop
);
408 NIR_PASS(progress
, nir
, nir_opt_dce
);
409 NIR_PASS(progress
, nir
, nir_opt_dead_cf
);
410 NIR_PASS(progress
, nir
, nir_opt_cse
);
411 NIR_PASS(progress
, nir
, nir_opt_peephole_select
, 64, false, true);
412 NIR_PASS(progress
, nir
, nir_opt_algebraic
);
413 NIR_PASS(progress
, nir
, nir_opt_constant_folding
);
415 if (lower_flrp
!= 0) {
416 bool lower_flrp_progress
= false;
417 NIR_PASS(lower_flrp_progress
,
421 false /* always_precise */,
422 nir
->options
->lower_ffma
);
423 if (lower_flrp_progress
) {
424 NIR_PASS(progress
, nir
,
425 nir_opt_constant_folding
);
429 /* Nothing should rematerialize any flrps, so we only
430 * need to do this lowering once.
435 NIR_PASS(progress
, nir
, nir_opt_undef
);
436 NIR_PASS(progress
, nir
, nir_opt_loop_unroll
,
439 nir_var_function_temp
);
441 /* TODO: Enable vectorize when merged upstream */
442 // NIR_PASS(progress, nir, nir_opt_vectorize);
445 /* Must be run at the end to prevent creation of fsin/fcos ops */
446 NIR_PASS(progress
, nir
, midgard_nir_scale_trig
);
451 NIR_PASS(progress
, nir
, nir_opt_dce
);
452 NIR_PASS(progress
, nir
, nir_opt_algebraic
);
453 NIR_PASS(progress
, nir
, nir_opt_constant_folding
);
454 NIR_PASS(progress
, nir
, nir_copy_prop
);
457 NIR_PASS(progress
, nir
, nir_opt_algebraic_late
);
459 /* We implement booleans as 32-bit 0/~0 */
460 NIR_PASS(progress
, nir
, nir_lower_bool_to_int32
);
462 /* Now that booleans are lowered, we can run out late opts */
463 NIR_PASS(progress
, nir
, midgard_nir_lower_algebraic_late
);
465 /* Lower mods for float ops only. Integer ops don't support modifiers
466 * (saturate doesn't make sense on integers, neg/abs require dedicated
469 NIR_PASS(progress
, nir
, nir_lower_to_source_mods
, nir_lower_float_source_mods
);
470 NIR_PASS(progress
, nir
, nir_copy_prop
);
471 NIR_PASS(progress
, nir
, nir_opt_dce
);
473 /* Take us out of SSA */
474 NIR_PASS(progress
, nir
, nir_lower_locals_to_regs
);
475 NIR_PASS(progress
, nir
, nir_convert_from_ssa
, true);
477 /* We are a vector architecture; write combine where possible */
478 NIR_PASS(progress
, nir
, nir_move_vec_src_uses_to_dest
);
479 NIR_PASS(progress
, nir
, nir_lower_vec_to_movs
);
481 NIR_PASS(progress
, nir
, nir_opt_dce
);
484 /* Front-half of aliasing the SSA slots, merely by inserting the flag in the
485 * appropriate hash table. Intentional off-by-one to avoid confusing NULL with
486 * r0. See the comments in compiler_context */
489 alias_ssa(compiler_context
*ctx
, int dest
, int src
)
491 _mesa_hash_table_u64_insert(ctx
->ssa_to_alias
, dest
+ 1, (void *) ((uintptr_t) src
+ 1));
492 _mesa_set_add(ctx
->leftover_ssa_to_alias
, (void *) (uintptr_t) (dest
+ 1));
495 /* ...or undo it, after which the original index will be used (dummy move should be emitted alongside this) */
498 unalias_ssa(compiler_context
*ctx
, int dest
)
500 _mesa_hash_table_u64_remove(ctx
->ssa_to_alias
, dest
+ 1);
501 /* TODO: Remove from leftover or no? */
504 /* Do not actually emit a load; instead, cache the constant for inlining */
507 emit_load_const(compiler_context
*ctx
, nir_load_const_instr
*instr
)
509 nir_ssa_def def
= instr
->def
;
511 float *v
= rzalloc_array(NULL
, float, 4);
512 nir_const_load_to_arr(v
, instr
, f32
);
513 _mesa_hash_table_u64_insert(ctx
->ssa_constants
, def
.index
+ 1, v
);
517 nir_src_index(compiler_context
*ctx
, nir_src
*src
)
520 return src
->ssa
->index
;
522 assert(!src
->reg
.indirect
);
523 return ctx
->func
->impl
->ssa_alloc
+ src
->reg
.reg
->index
;
528 nir_dest_index(compiler_context
*ctx
, nir_dest
*dst
)
531 return dst
->ssa
.index
;
533 assert(!dst
->reg
.indirect
);
534 return ctx
->func
->impl
->ssa_alloc
+ dst
->reg
.reg
->index
;
539 nir_alu_src_index(compiler_context
*ctx
, nir_alu_src
*src
)
541 return nir_src_index(ctx
, &src
->src
);
545 nir_is_non_scalar_swizzle(nir_alu_src
*src
, unsigned nr_components
)
547 unsigned comp
= src
->swizzle
[0];
549 for (unsigned c
= 1; c
< nr_components
; ++c
) {
550 if (src
->swizzle
[c
] != comp
)
557 /* Midgard puts scalar conditionals in r31.w; move an arbitrary source (the
558 * output of a conditional test) into that register */
561 emit_condition(compiler_context
*ctx
, nir_src
*src
, bool for_branch
, unsigned component
)
563 int condition
= nir_src_index(ctx
, src
);
565 /* Source to swizzle the desired component into w */
567 const midgard_vector_alu_src alu_src
= {
568 .swizzle
= SWIZZLE(component
, component
, component
, component
),
571 /* There is no boolean move instruction. Instead, we simulate a move by
572 * ANDing the condition with itself to get it into r31.w */
574 midgard_instruction ins
= {
577 /* We need to set the conditional as close as possible */
578 .precede_break
= true,
579 .unit
= for_branch
? UNIT_SMUL
: UNIT_SADD
,
585 .dest
= SSA_FIXED_REGISTER(31),
588 .op
= midgard_alu_op_iand
,
589 .outmod
= midgard_outmod_int
,
590 .reg_mode
= midgard_reg_mode_32
,
591 .dest_override
= midgard_dest_override_none
,
592 .mask
= (0x3 << 6), /* w */
593 .src1
= vector_alu_srco_unsigned(alu_src
),
594 .src2
= vector_alu_srco_unsigned(alu_src
)
598 emit_mir_instruction(ctx
, ins
);
601 /* Or, for mixed conditions (with csel_v), here's a vector version using all of
605 emit_condition_mixed(compiler_context
*ctx
, nir_alu_src
*src
, unsigned nr_comp
)
607 int condition
= nir_src_index(ctx
, &src
->src
);
609 /* Source to swizzle the desired component into w */
611 const midgard_vector_alu_src alu_src
= {
612 .swizzle
= SWIZZLE_FROM_ARRAY(src
->swizzle
),
615 /* There is no boolean move instruction. Instead, we simulate a move by
616 * ANDing the condition with itself to get it into r31.w */
618 midgard_instruction ins
= {
620 .precede_break
= true,
624 .dest
= SSA_FIXED_REGISTER(31),
627 .op
= midgard_alu_op_iand
,
628 .outmod
= midgard_outmod_int
,
629 .reg_mode
= midgard_reg_mode_32
,
630 .dest_override
= midgard_dest_override_none
,
631 .mask
= expand_writemask((1 << nr_comp
) - 1),
632 .src1
= vector_alu_srco_unsigned(alu_src
),
633 .src2
= vector_alu_srco_unsigned(alu_src
)
637 emit_mir_instruction(ctx
, ins
);
642 /* Likewise, indirect offsets are put in r27.w. TODO: Allow componentwise
643 * pinning to eliminate this move in all known cases */
646 emit_indirect_offset(compiler_context
*ctx
, nir_src
*src
)
648 int offset
= nir_src_index(ctx
, src
);
650 midgard_instruction ins
= {
653 .src0
= SSA_UNUSED_1
,
655 .dest
= SSA_FIXED_REGISTER(REGISTER_OFFSET
),
658 .op
= midgard_alu_op_imov
,
659 .outmod
= midgard_outmod_int
,
660 .reg_mode
= midgard_reg_mode_32
,
661 .dest_override
= midgard_dest_override_none
,
662 .mask
= (0x3 << 6), /* w */
663 .src1
= vector_alu_srco_unsigned(zero_alu_src
),
664 .src2
= vector_alu_srco_unsigned(blank_alu_src_xxxx
)
668 emit_mir_instruction(ctx
, ins
);
671 #define ALU_CASE(nir, _op) \
673 op = midgard_alu_op_##_op; \
676 nir_is_fzero_constant(nir_src src
)
678 if (!nir_src_is_const(src
))
681 for (unsigned c
= 0; c
< nir_src_num_components(src
); ++c
) {
682 if (nir_src_comp_as_float(src
, c
) != 0.0)
690 emit_alu(compiler_context
*ctx
, nir_alu_instr
*instr
)
692 bool is_ssa
= instr
->dest
.dest
.is_ssa
;
694 unsigned dest
= nir_dest_index(ctx
, &instr
->dest
.dest
);
695 unsigned nr_components
= is_ssa
? instr
->dest
.dest
.ssa
.num_components
: instr
->dest
.dest
.reg
.reg
->num_components
;
696 unsigned nr_inputs
= nir_op_infos
[instr
->op
].num_inputs
;
698 /* Most Midgard ALU ops have a 1:1 correspondance to NIR ops; these are
699 * supported. A few do not and are commented for now. Also, there are a
700 * number of NIR ops which Midgard does not support and need to be
701 * lowered, also TODO. This switch block emits the opcode and calling
702 * convention of the Midgard instruction; actual packing is done in
708 ALU_CASE(fadd
, fadd
);
709 ALU_CASE(fmul
, fmul
);
710 ALU_CASE(fmin
, fmin
);
711 ALU_CASE(fmax
, fmax
);
712 ALU_CASE(imin
, imin
);
713 ALU_CASE(imax
, imax
);
714 ALU_CASE(umin
, umin
);
715 ALU_CASE(umax
, umax
);
716 ALU_CASE(ffloor
, ffloor
);
717 ALU_CASE(fround_even
, froundeven
);
718 ALU_CASE(ftrunc
, ftrunc
);
719 ALU_CASE(fceil
, fceil
);
720 ALU_CASE(fdot3
, fdot3
);
721 ALU_CASE(fdot4
, fdot4
);
722 ALU_CASE(iadd
, iadd
);
723 ALU_CASE(isub
, isub
);
724 ALU_CASE(imul
, imul
);
725 ALU_CASE(iabs
, iabs
);
728 ALU_CASE(feq32
, feq
);
729 ALU_CASE(fne32
, fne
);
730 ALU_CASE(flt32
, flt
);
731 ALU_CASE(ieq32
, ieq
);
732 ALU_CASE(ine32
, ine
);
733 ALU_CASE(ilt32
, ilt
);
734 ALU_CASE(ult32
, ult
);
736 /* We don't have a native b2f32 instruction. Instead, like many
737 * GPUs, we exploit booleans as 0/~0 for false/true, and
738 * correspondingly AND
739 * by 1.0 to do the type conversion. For the moment, prime us
742 * iand [whatever], #0
744 * At the end of emit_alu (as MIR), we'll fix-up the constant
747 ALU_CASE(b2f32
, iand
);
748 ALU_CASE(b2i32
, iand
);
750 /* Likewise, we don't have a dedicated f2b32 instruction, but
751 * we can do a "not equal to 0.0" test. */
753 ALU_CASE(f2b32
, fne
);
754 ALU_CASE(i2b32
, ine
);
756 ALU_CASE(frcp
, frcp
);
757 ALU_CASE(frsq
, frsqrt
);
758 ALU_CASE(fsqrt
, fsqrt
);
759 ALU_CASE(fexp2
, fexp2
);
760 ALU_CASE(flog2
, flog2
);
762 ALU_CASE(f2i32
, f2i
);
763 ALU_CASE(f2u32
, f2u
);
764 ALU_CASE(i2f32
, i2f
);
765 ALU_CASE(u2f32
, u2f
);
767 ALU_CASE(fsin
, fsin
);
768 ALU_CASE(fcos
, fcos
);
770 ALU_CASE(iand
, iand
);
772 ALU_CASE(ixor
, ixor
);
773 ALU_CASE(inot
, inand
);
774 ALU_CASE(ishl
, ishl
);
775 ALU_CASE(ishr
, iasr
);
776 ALU_CASE(ushr
, ilsr
);
778 ALU_CASE(b32all_fequal2
, fball_eq
);
779 ALU_CASE(b32all_fequal3
, fball_eq
);
780 ALU_CASE(b32all_fequal4
, fball_eq
);
782 ALU_CASE(b32any_fnequal2
, fbany_neq
);
783 ALU_CASE(b32any_fnequal3
, fbany_neq
);
784 ALU_CASE(b32any_fnequal4
, fbany_neq
);
786 ALU_CASE(b32all_iequal2
, iball_eq
);
787 ALU_CASE(b32all_iequal3
, iball_eq
);
788 ALU_CASE(b32all_iequal4
, iball_eq
);
790 ALU_CASE(b32any_inequal2
, ibany_neq
);
791 ALU_CASE(b32any_inequal3
, ibany_neq
);
792 ALU_CASE(b32any_inequal4
, ibany_neq
);
794 /* Source mods will be shoved in later */
795 ALU_CASE(fabs
, fmov
);
796 ALU_CASE(fneg
, fmov
);
797 ALU_CASE(fsat
, fmov
);
799 /* For greater-or-equal, we lower to less-or-equal and flip the
807 instr
->op
== nir_op_fge
? midgard_alu_op_fle
:
808 instr
->op
== nir_op_fge32
? midgard_alu_op_fle
:
809 instr
->op
== nir_op_ige32
? midgard_alu_op_ile
:
810 instr
->op
== nir_op_uge32
? midgard_alu_op_ule
:
813 /* Swap via temporary */
814 nir_alu_src temp
= instr
->src
[1];
815 instr
->src
[1] = instr
->src
[0];
816 instr
->src
[0] = temp
;
821 case nir_op_b32csel
: {
822 /* Midgard features both fcsel and icsel, depending on
823 * the type of the arguments/output. However, as long
824 * as we're careful we can _always_ use icsel and
825 * _never_ need fcsel, since the latter does additional
826 * floating-point-specific processing whereas the
827 * former just moves bits on the wire. It's not obvious
828 * why these are separate opcodes, save for the ability
829 * to do things like sat/pos/abs/neg for free */
831 bool mixed
= nir_is_non_scalar_swizzle(&instr
->src
[0], nr_components
);
832 op
= mixed
? midgard_alu_op_icsel_v
: midgard_alu_op_icsel
;
834 /* csel works as a two-arg in Midgard, since the condition is hardcoded in r31.w */
837 /* Emit the condition into r31 */
840 emit_condition_mixed(ctx
, &instr
->src
[0], nr_components
);
842 emit_condition(ctx
, &instr
->src
[0].src
, false, instr
->src
[0].swizzle
[0]);
844 /* The condition is the first argument; move the other
845 * arguments up one to be a binary instruction for
848 memmove(instr
->src
, instr
->src
+ 1, 2 * sizeof(nir_alu_src
));
853 DBG("Unhandled ALU op %s\n", nir_op_infos
[instr
->op
].name
);
858 /* Midgard can perform certain modifiers on output of an ALU op */
859 midgard_outmod outmod
=
860 midgard_is_integer_out_op(op
) ? midgard_outmod_int
:
861 instr
->dest
.saturate
? midgard_outmod_sat
: midgard_outmod_none
;
863 if (instr
->op
== nir_op_fsat
)
864 outmod
= midgard_outmod_sat
;
866 /* fmax(a, 0.0) can turn into a .pos modifier as an optimization */
868 if (instr
->op
== nir_op_fmax
) {
869 if (nir_is_fzero_constant(instr
->src
[0].src
)) {
870 op
= midgard_alu_op_fmov
;
872 outmod
= midgard_outmod_pos
;
873 instr
->src
[0] = instr
->src
[1];
874 } else if (nir_is_fzero_constant(instr
->src
[1].src
)) {
875 op
= midgard_alu_op_fmov
;
877 outmod
= midgard_outmod_pos
;
881 /* Fetch unit, quirks, etc information */
882 unsigned opcode_props
= alu_opcode_props
[op
].props
;
883 bool quirk_flipped_r24
= opcode_props
& QUIRK_FLIPPED_R24
;
885 /* src0 will always exist afaik, but src1 will not for 1-argument
886 * instructions. The latter can only be fetched if the instruction
887 * needs it, or else we may segfault. */
889 unsigned src0
= nir_alu_src_index(ctx
, &instr
->src
[0]);
890 unsigned src1
= nr_inputs
== 2 ? nir_alu_src_index(ctx
, &instr
->src
[1]) : SSA_UNUSED_0
;
892 /* Rather than use the instruction generation helpers, we do it
893 * ourselves here to avoid the mess */
895 midgard_instruction ins
= {
898 .src0
= quirk_flipped_r24
? SSA_UNUSED_1
: src0
,
899 .src1
= quirk_flipped_r24
? src0
: src1
,
904 nir_alu_src
*nirmods
[2] = { NULL
};
906 if (nr_inputs
== 2) {
907 nirmods
[0] = &instr
->src
[0];
908 nirmods
[1] = &instr
->src
[1];
909 } else if (nr_inputs
== 1) {
910 nirmods
[quirk_flipped_r24
] = &instr
->src
[0];
915 /* These were lowered to a move, so apply the corresponding mod */
917 if (instr
->op
== nir_op_fneg
|| instr
->op
== nir_op_fabs
) {
918 nir_alu_src
*s
= nirmods
[quirk_flipped_r24
];
920 if (instr
->op
== nir_op_fneg
)
921 s
->negate
= !s
->negate
;
923 if (instr
->op
== nir_op_fabs
)
927 bool is_int
= midgard_is_integer_op(op
);
929 midgard_vector_alu alu
= {
931 .reg_mode
= midgard_reg_mode_32
,
932 .dest_override
= midgard_dest_override_none
,
935 /* Writemask only valid for non-SSA NIR */
936 .mask
= expand_writemask((1 << nr_components
) - 1),
938 .src1
= vector_alu_srco_unsigned(vector_alu_modifiers(nirmods
[0], is_int
)),
939 .src2
= vector_alu_srco_unsigned(vector_alu_modifiers(nirmods
[1], is_int
)),
942 /* Apply writemask if non-SSA, keeping in mind that we can't write to components that don't exist */
945 alu
.mask
&= expand_writemask(instr
->dest
.write_mask
);
949 /* Late fixup for emulated instructions */
951 if (instr
->op
== nir_op_b2f32
|| instr
->op
== nir_op_b2i32
) {
952 /* Presently, our second argument is an inline #0 constant.
953 * Switch over to an embedded 1.0 constant (that can't fit
954 * inline, since we're 32-bit, not 16-bit like the inline
957 ins
.ssa_args
.inline_constant
= false;
958 ins
.ssa_args
.src1
= SSA_FIXED_REGISTER(REGISTER_CONSTANT
);
959 ins
.has_constants
= true;
961 if (instr
->op
== nir_op_b2f32
) {
962 ins
.constants
[0] = 1.0f
;
964 /* Type pun it into place */
966 memcpy(&ins
.constants
[0], &one
, sizeof(uint32_t));
969 ins
.alu
.src2
= vector_alu_srco_unsigned(blank_alu_src_xxxx
);
970 } else if (instr
->op
== nir_op_f2b32
|| instr
->op
== nir_op_i2b32
) {
971 ins
.ssa_args
.inline_constant
= false;
972 ins
.ssa_args
.src1
= SSA_FIXED_REGISTER(REGISTER_CONSTANT
);
973 ins
.has_constants
= true;
974 ins
.constants
[0] = 0.0f
;
975 ins
.alu
.src2
= vector_alu_srco_unsigned(blank_alu_src_xxxx
);
976 } else if (instr
->op
== nir_op_inot
) {
977 /* ~b = ~(b & b), so duplicate the source */
978 ins
.ssa_args
.src1
= ins
.ssa_args
.src0
;
979 ins
.alu
.src2
= ins
.alu
.src1
;
982 if ((opcode_props
& UNITS_ALL
) == UNIT_VLUT
) {
983 /* To avoid duplicating the lookup tables (probably), true LUT
984 * instructions can only operate as if they were scalars. Lower
985 * them here by changing the component. */
987 uint8_t original_swizzle
[4];
988 memcpy(original_swizzle
, nirmods
[0]->swizzle
, sizeof(nirmods
[0]->swizzle
));
990 for (int i
= 0; i
< nr_components
; ++i
) {
991 ins
.alu
.mask
= (0x3) << (2 * i
); /* Mask the associated component */
993 for (int j
= 0; j
< 4; ++j
)
994 nirmods
[0]->swizzle
[j
] = original_swizzle
[i
]; /* Pull from the correct component */
996 ins
.alu
.src1
= vector_alu_srco_unsigned(vector_alu_modifiers(nirmods
[0], is_int
));
997 emit_mir_instruction(ctx
, ins
);
1000 emit_mir_instruction(ctx
, ins
);
1007 emit_uniform_read(compiler_context
*ctx
, unsigned dest
, unsigned offset
, nir_src
*indirect_offset
)
1009 /* TODO: half-floats */
1011 if (!indirect_offset
&& offset
< ctx
->uniform_cutoff
) {
1012 /* Fast path: For the first 16 uniforms, direct accesses are
1013 * 0-cycle, since they're just a register fetch in the usual
1014 * case. So, we alias the registers while we're still in
1017 int reg_slot
= 23 - offset
;
1018 alias_ssa(ctx
, dest
, SSA_FIXED_REGISTER(reg_slot
));
1020 /* Otherwise, read from the 'special' UBO to access
1021 * higher-indexed uniforms, at a performance cost. More
1022 * generally, we're emitting a UBO read instruction. */
1024 midgard_instruction ins
= m_ld_uniform_32(dest
, offset
);
1026 /* TODO: Don't split */
1027 ins
.load_store
.varying_parameters
= (offset
& 7) << 7;
1028 ins
.load_store
.address
= offset
>> 3;
1030 if (indirect_offset
) {
1031 emit_indirect_offset(ctx
, indirect_offset
);
1032 ins
.load_store
.unknown
= 0x8700; /* xxx: what is this? */
1034 ins
.load_store
.unknown
= 0x1E00; /* xxx: what is this? */
1037 emit_mir_instruction(ctx
, ins
);
1042 emit_sysval_read(compiler_context
*ctx
, nir_intrinsic_instr
*instr
)
1044 /* First, pull out the destination */
1045 unsigned dest
= nir_dest_index(ctx
, &instr
->dest
);
1047 /* Now, figure out which uniform this is */
1048 int sysval
= midgard_nir_sysval_for_intrinsic(instr
);
1049 void *val
= _mesa_hash_table_u64_search(ctx
->sysval_to_id
, sysval
);
1051 /* Sysvals are prefix uniforms */
1052 unsigned uniform
= ((uintptr_t) val
) - 1;
1054 /* Emit the read itself -- this is never indirect */
1055 emit_uniform_read(ctx
, dest
, uniform
, NULL
);
1058 /* Reads RGBA8888 value from the tilebuffer and converts to a RGBA32F register,
1059 * using scalar ops functional on earlier Midgard generations. Newer Midgard
1060 * generations have faster vectorized reads. This operation is for blend
1061 * shaders in particular; reading the tilebuffer from the fragment shader
1062 * remains an open problem. */
1065 emit_fb_read_blend_scalar(compiler_context
*ctx
, unsigned reg
)
1067 midgard_instruction ins
= m_ld_color_buffer_8(reg
, 0);
1068 ins
.load_store
.swizzle
= 0; /* xxxx */
1070 /* Read each component sequentially */
1072 for (unsigned c
= 0; c
< 4; ++c
) {
1073 ins
.load_store
.mask
= (1 << c
);
1074 ins
.load_store
.unknown
= c
;
1075 emit_mir_instruction(ctx
, ins
);
1078 /* vadd.u2f hr2, zext(hr2), #0 */
1080 midgard_vector_alu_src alu_src
= blank_alu_src
;
1081 alu_src
.mod
= midgard_int_zero_extend
;
1082 alu_src
.half
= true;
1084 midgard_instruction u2f
= {
1088 .src1
= SSA_UNUSED_0
,
1090 .inline_constant
= true
1093 .op
= midgard_alu_op_u2f
,
1094 .reg_mode
= midgard_reg_mode_16
,
1095 .dest_override
= midgard_dest_override_none
,
1097 .src1
= vector_alu_srco_unsigned(alu_src
),
1098 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
1102 emit_mir_instruction(ctx
, u2f
);
1104 /* vmul.fmul.sat r1, hr2, #0.00392151 */
1108 midgard_instruction fmul
= {
1110 .inline_constant
= _mesa_float_to_half(1.0 / 255.0),
1114 .src1
= SSA_UNUSED_0
,
1115 .inline_constant
= true
1118 .op
= midgard_alu_op_fmul
,
1119 .reg_mode
= midgard_reg_mode_32
,
1120 .dest_override
= midgard_dest_override_none
,
1121 .outmod
= midgard_outmod_sat
,
1123 .src1
= vector_alu_srco_unsigned(alu_src
),
1124 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
1128 emit_mir_instruction(ctx
, fmul
);
1132 emit_intrinsic(compiler_context
*ctx
, nir_intrinsic_instr
*instr
)
1134 unsigned offset
, reg
;
1136 switch (instr
->intrinsic
) {
1137 case nir_intrinsic_discard_if
:
1138 emit_condition(ctx
, &instr
->src
[0], true, COMPONENT_X
);
1142 case nir_intrinsic_discard
: {
1143 bool conditional
= instr
->intrinsic
== nir_intrinsic_discard_if
;
1144 struct midgard_instruction discard
= v_branch(conditional
, false);
1145 discard
.branch
.target_type
= TARGET_DISCARD
;
1146 emit_mir_instruction(ctx
, discard
);
1148 ctx
->can_discard
= true;
1152 case nir_intrinsic_load_uniform
:
1153 case nir_intrinsic_load_input
:
1154 offset
= nir_intrinsic_base(instr
);
1156 bool direct
= nir_src_is_const(instr
->src
[0]);
1159 offset
+= nir_src_as_uint(instr
->src
[0]);
1162 reg
= nir_dest_index(ctx
, &instr
->dest
);
1164 if (instr
->intrinsic
== nir_intrinsic_load_uniform
&& !ctx
->is_blend
) {
1165 emit_uniform_read(ctx
, reg
, ctx
->sysval_count
+ offset
, !direct
? &instr
->src
[0] : NULL
);
1166 } else if (ctx
->stage
== MESA_SHADER_FRAGMENT
&& !ctx
->is_blend
) {
1167 /* XXX: Half-floats? */
1168 /* TODO: swizzle, mask */
1170 midgard_instruction ins
= m_ld_vary_32(reg
, offset
);
1172 midgard_varying_parameter p
= {
1174 .interpolation
= midgard_interp_default
,
1175 .flat
= /*var->data.interpolation == INTERP_MODE_FLAT*/ 0
1179 memcpy(&u
, &p
, sizeof(p
));
1180 ins
.load_store
.varying_parameters
= u
;
1183 /* We have the offset totally ready */
1184 ins
.load_store
.unknown
= 0x1e9e; /* xxx: what is this? */
1186 /* We have it partially ready, but we need to
1187 * add in the dynamic index, moved to r27.w */
1188 emit_indirect_offset(ctx
, &instr
->src
[0]);
1189 ins
.load_store
.unknown
= 0x79e; /* xxx: what is this? */
1192 emit_mir_instruction(ctx
, ins
);
1193 } else if (ctx
->is_blend
) {
1194 /* For blend shaders, load the input color, which is
1195 * preloaded to r0 */
1197 midgard_instruction move
= v_fmov(reg
, blank_alu_src
, SSA_FIXED_REGISTER(0));
1198 emit_mir_instruction(ctx
, move
);
1199 } else if (ctx
->stage
== MESA_SHADER_VERTEX
) {
1200 midgard_instruction ins
= m_ld_attr_32(reg
, offset
);
1201 ins
.load_store
.unknown
= 0x1E1E; /* XXX: What is this? */
1202 ins
.load_store
.mask
= (1 << instr
->num_components
) - 1;
1203 emit_mir_instruction(ctx
, ins
);
1205 DBG("Unknown load\n");
1211 case nir_intrinsic_load_output
:
1212 assert(nir_src_is_const(instr
->src
[0]));
1213 reg
= nir_dest_index(ctx
, &instr
->dest
);
1215 if (ctx
->is_blend
) {
1217 emit_fb_read_blend_scalar(ctx
, reg
);
1219 DBG("Unknown output load\n");
1225 case nir_intrinsic_load_blend_const_color_rgba
: {
1226 assert(ctx
->is_blend
);
1227 reg
= nir_dest_index(ctx
, &instr
->dest
);
1229 /* Blend constants are embedded directly in the shader and
1230 * patched in, so we use some magic routing */
1232 midgard_instruction ins
= v_fmov(SSA_FIXED_REGISTER(REGISTER_CONSTANT
), blank_alu_src
, reg
);
1233 ins
.has_constants
= true;
1234 ins
.has_blend_constant
= true;
1235 emit_mir_instruction(ctx
, ins
);
1239 case nir_intrinsic_store_output
:
1240 assert(nir_src_is_const(instr
->src
[1]) && "no indirect outputs");
1242 offset
= nir_intrinsic_base(instr
) + nir_src_as_uint(instr
->src
[1]);
1244 reg
= nir_src_index(ctx
, &instr
->src
[0]);
1246 if (ctx
->stage
== MESA_SHADER_FRAGMENT
) {
1247 /* gl_FragColor is not emitted with load/store
1248 * instructions. Instead, it gets plonked into
1249 * r0 at the end of the shader and we do the
1250 * framebuffer writeout dance. TODO: Defer
1253 midgard_instruction move
= v_fmov(reg
, blank_alu_src
, SSA_FIXED_REGISTER(0));
1254 emit_mir_instruction(ctx
, move
);
1256 /* Save the index we're writing to for later reference
1257 * in the epilogue */
1259 ctx
->fragment_output
= reg
;
1260 } else if (ctx
->stage
== MESA_SHADER_VERTEX
) {
1261 /* Varyings are written into one of two special
1262 * varying register, r26 or r27. The register itself is selected as the register
1263 * in the st_vary instruction, minus the base of 26. E.g. write into r27 and then call st_vary(1)
1265 * Normally emitting fmov's is frowned upon,
1266 * but due to unique constraints of
1267 * REGISTER_VARYING, fmov emission + a
1268 * dedicated cleanup pass is the only way to
1269 * guarantee correctness when considering some
1270 * (common) edge cases XXX: FIXME */
1272 /* If this varying corresponds to a constant (why?!),
1273 * emit that now since it won't get picked up by
1274 * hoisting (since there is no corresponding move
1275 * emitted otherwise) */
1277 void *constant_value
= _mesa_hash_table_u64_search(ctx
->ssa_constants
, reg
+ 1);
1279 if (constant_value
) {
1280 /* Special case: emit the varying write
1281 * directly to r26 (looks funny in asm but it's
1282 * fine) and emit the store _now_. Possibly
1283 * slightly slower, but this is a really stupid
1284 * special case anyway (why on earth would you
1285 * have a constant varying? Your own fault for
1286 * slightly worse perf :P) */
1288 midgard_instruction ins
= v_fmov(SSA_FIXED_REGISTER(REGISTER_CONSTANT
), blank_alu_src
, SSA_FIXED_REGISTER(26));
1289 attach_constants(ctx
, &ins
, constant_value
, reg
+ 1);
1290 emit_mir_instruction(ctx
, ins
);
1292 midgard_instruction st
= m_st_vary_32(SSA_FIXED_REGISTER(0), offset
);
1293 st
.load_store
.unknown
= 0x1E9E; /* XXX: What is this? */
1294 emit_mir_instruction(ctx
, st
);
1296 /* Do not emit the varying yet -- instead, just mark down that we need to later */
1298 _mesa_hash_table_u64_insert(ctx
->ssa_varyings
, reg
+ 1, (void *) ((uintptr_t) (offset
+ 1)));
1301 DBG("Unknown store\n");
1307 case nir_intrinsic_load_alpha_ref_float
:
1308 assert(instr
->dest
.is_ssa
);
1310 float ref_value
= ctx
->alpha_ref
;
1312 float *v
= ralloc_array(NULL
, float, 4);
1313 memcpy(v
, &ref_value
, sizeof(float));
1314 _mesa_hash_table_u64_insert(ctx
->ssa_constants
, instr
->dest
.ssa
.index
+ 1, v
);
1317 case nir_intrinsic_load_viewport_scale
:
1318 case nir_intrinsic_load_viewport_offset
:
1319 emit_sysval_read(ctx
, instr
);
1323 printf ("Unhandled intrinsic\n");
1330 midgard_tex_format(enum glsl_sampler_dim dim
)
1333 case GLSL_SAMPLER_DIM_2D
:
1334 case GLSL_SAMPLER_DIM_EXTERNAL
:
1337 case GLSL_SAMPLER_DIM_3D
:
1340 case GLSL_SAMPLER_DIM_CUBE
:
1341 return TEXTURE_CUBE
;
1344 DBG("Unknown sampler dim type\n");
1351 emit_tex(compiler_context
*ctx
, nir_tex_instr
*instr
)
1354 //assert (!instr->sampler);
1355 //assert (!instr->texture_array_size);
1356 assert (instr
->op
== nir_texop_tex
);
1358 /* Allocate registers via a round robin scheme to alternate between the two registers */
1359 int reg
= ctx
->texture_op_count
& 1;
1360 int in_reg
= reg
, out_reg
= reg
;
1362 /* Make room for the reg */
1364 if (ctx
->texture_index
[reg
] > -1)
1365 unalias_ssa(ctx
, ctx
->texture_index
[reg
]);
1367 int texture_index
= instr
->texture_index
;
1368 int sampler_index
= texture_index
;
1370 for (unsigned i
= 0; i
< instr
->num_srcs
; ++i
) {
1371 switch (instr
->src
[i
].src_type
) {
1372 case nir_tex_src_coord
: {
1373 int index
= nir_src_index(ctx
, &instr
->src
[i
].src
);
1375 midgard_vector_alu_src alu_src
= blank_alu_src
;
1377 int reg
= SSA_FIXED_REGISTER(REGISTER_TEXTURE_BASE
+ in_reg
);
1379 if (instr
->sampler_dim
== GLSL_SAMPLER_DIM_CUBE
) {
1380 /* For cubemaps, we need to load coords into
1381 * special r27, and then use a special ld/st op
1382 * to copy into the texture register */
1384 alu_src
.swizzle
= SWIZZLE(COMPONENT_X
, COMPONENT_Y
, COMPONENT_Z
, COMPONENT_X
);
1386 midgard_instruction move
= v_fmov(index
, alu_src
, SSA_FIXED_REGISTER(27));
1387 emit_mir_instruction(ctx
, move
);
1389 midgard_instruction st
= m_st_cubemap_coords(reg
, 0);
1390 st
.load_store
.unknown
= 0x24; /* XXX: What is this? */
1391 st
.load_store
.mask
= 0x3; /* xy? */
1392 st
.load_store
.swizzle
= alu_src
.swizzle
;
1393 emit_mir_instruction(ctx
, st
);
1396 alu_src
.swizzle
= SWIZZLE(COMPONENT_X
, COMPONENT_Y
, COMPONENT_X
, COMPONENT_X
);
1398 midgard_instruction ins
= v_fmov(index
, alu_src
, reg
);
1399 emit_mir_instruction(ctx
, ins
);
1406 DBG("Unknown source type\n");
1413 /* No helper to build texture words -- we do it all here */
1414 midgard_instruction ins
= {
1415 .type
= TAG_TEXTURE_4
,
1417 .op
= TEXTURE_OP_NORMAL
,
1418 .format
= midgard_tex_format(instr
->sampler_dim
),
1419 .texture_handle
= texture_index
,
1420 .sampler_handle
= sampler_index
,
1422 /* TODO: Don't force xyzw */
1423 .swizzle
= SWIZZLE(COMPONENT_X
, COMPONENT_Y
, COMPONENT_Z
, COMPONENT_W
),
1435 /* Assume we can continue; hint it out later */
1440 /* Set registers to read and write from the same place */
1441 ins
.texture
.in_reg_select
= in_reg
;
1442 ins
.texture
.out_reg_select
= out_reg
;
1444 /* TODO: Dynamic swizzle input selection, half-swizzles? */
1445 if (instr
->sampler_dim
== GLSL_SAMPLER_DIM_3D
) {
1446 ins
.texture
.in_reg_swizzle_right
= COMPONENT_X
;
1447 ins
.texture
.in_reg_swizzle_left
= COMPONENT_Y
;
1448 //ins.texture.in_reg_swizzle_third = COMPONENT_Z;
1450 ins
.texture
.in_reg_swizzle_left
= COMPONENT_X
;
1451 ins
.texture
.in_reg_swizzle_right
= COMPONENT_Y
;
1452 //ins.texture.in_reg_swizzle_third = COMPONENT_X;
1455 emit_mir_instruction(ctx
, ins
);
1457 /* Simultaneously alias the destination and emit a move for it. The move will be eliminated if possible */
1459 int o_reg
= REGISTER_TEXTURE_BASE
+ out_reg
, o_index
= nir_dest_index(ctx
, &instr
->dest
);
1460 alias_ssa(ctx
, o_index
, SSA_FIXED_REGISTER(o_reg
));
1461 ctx
->texture_index
[reg
] = o_index
;
1463 midgard_instruction ins2
= v_fmov(SSA_FIXED_REGISTER(o_reg
), blank_alu_src
, o_index
);
1464 emit_mir_instruction(ctx
, ins2
);
1466 /* Used for .cont and .last hinting */
1467 ctx
->texture_op_count
++;
1471 emit_jump(compiler_context
*ctx
, nir_jump_instr
*instr
)
1473 switch (instr
->type
) {
1474 case nir_jump_break
: {
1475 /* Emit a branch out of the loop */
1476 struct midgard_instruction br
= v_branch(false, false);
1477 br
.branch
.target_type
= TARGET_BREAK
;
1478 br
.branch
.target_break
= ctx
->current_loop_depth
;
1479 emit_mir_instruction(ctx
, br
);
1486 DBG("Unknown jump type %d\n", instr
->type
);
1492 emit_instr(compiler_context
*ctx
, struct nir_instr
*instr
)
1494 switch (instr
->type
) {
1495 case nir_instr_type_load_const
:
1496 emit_load_const(ctx
, nir_instr_as_load_const(instr
));
1499 case nir_instr_type_intrinsic
:
1500 emit_intrinsic(ctx
, nir_instr_as_intrinsic(instr
));
1503 case nir_instr_type_alu
:
1504 emit_alu(ctx
, nir_instr_as_alu(instr
));
1507 case nir_instr_type_tex
:
1508 emit_tex(ctx
, nir_instr_as_tex(instr
));
1511 case nir_instr_type_jump
:
1512 emit_jump(ctx
, nir_instr_as_jump(instr
));
1515 case nir_instr_type_ssa_undef
:
1520 DBG("Unhandled instruction type\n");
1525 /* Midgard IR only knows vector ALU types, but we sometimes need to actually
1526 * use scalar ALU instructions, for functional or performance reasons. To do
1527 * this, we just demote vector ALU payloads to scalar. */
1530 component_from_mask(unsigned mask
)
1532 for (int c
= 0; c
< 4; ++c
) {
1533 if (mask
& (3 << (2 * c
)))
1542 is_single_component_mask(unsigned mask
)
1546 for (int c
= 0; c
< 4; ++c
)
1547 if (mask
& (3 << (2 * c
)))
1550 return components
== 1;
1553 /* Create a mask of accessed components from a swizzle to figure out vector
1557 swizzle_to_access_mask(unsigned swizzle
)
1559 unsigned component_mask
= 0;
1561 for (int i
= 0; i
< 4; ++i
) {
1562 unsigned c
= (swizzle
>> (2 * i
)) & 3;
1563 component_mask
|= (1 << c
);
1566 return component_mask
;
1570 vector_to_scalar_source(unsigned u
, bool is_int
)
1572 midgard_vector_alu_src v
;
1573 memcpy(&v
, &u
, sizeof(v
));
1575 /* TODO: Integers */
1577 midgard_scalar_alu_src s
= {
1579 .component
= (v
.swizzle
& 3) << 1
1585 s
.abs
= v
.mod
& MIDGARD_FLOAT_MOD_ABS
;
1586 s
.negate
= v
.mod
& MIDGARD_FLOAT_MOD_NEG
;
1590 memcpy(&o
, &s
, sizeof(s
));
1592 return o
& ((1 << 6) - 1);
1595 static midgard_scalar_alu
1596 vector_to_scalar_alu(midgard_vector_alu v
, midgard_instruction
*ins
)
1598 bool is_int
= midgard_is_integer_op(v
.op
);
1600 /* The output component is from the mask */
1601 midgard_scalar_alu s
= {
1603 .src1
= vector_to_scalar_source(v
.src1
, is_int
),
1604 .src2
= vector_to_scalar_source(v
.src2
, is_int
),
1607 .output_full
= 1, /* TODO: Half */
1608 .output_component
= component_from_mask(v
.mask
) << 1,
1611 /* Inline constant is passed along rather than trying to extract it
1614 if (ins
->ssa_args
.inline_constant
) {
1616 int lower_11
= ins
->inline_constant
& ((1 << 12) - 1);
1617 imm
|= (lower_11
>> 9) & 3;
1618 imm
|= (lower_11
>> 6) & 4;
1619 imm
|= (lower_11
>> 2) & 0x38;
1620 imm
|= (lower_11
& 63) << 6;
1628 /* Midgard prefetches instruction types, so during emission we need to
1629 * lookahead too. Unless this is the last instruction, in which we return 1. Or
1630 * if this is the second to last and the last is an ALU, then it's also 1... */
1632 #define IS_ALU(tag) (tag == TAG_ALU_4 || tag == TAG_ALU_8 || \
1633 tag == TAG_ALU_12 || tag == TAG_ALU_16)
1635 #define EMIT_AND_COUNT(type, val) util_dynarray_append(emission, type, val); \
1636 bytes_emitted += sizeof(type)
1639 emit_binary_vector_instruction(midgard_instruction
*ains
,
1640 uint16_t *register_words
, int *register_words_count
,
1641 uint64_t *body_words
, size_t *body_size
, int *body_words_count
,
1642 size_t *bytes_emitted
)
1644 memcpy(®ister_words
[(*register_words_count
)++], &ains
->registers
, sizeof(ains
->registers
));
1645 *bytes_emitted
+= sizeof(midgard_reg_info
);
1647 body_size
[*body_words_count
] = sizeof(midgard_vector_alu
);
1648 memcpy(&body_words
[(*body_words_count
)++], &ains
->alu
, sizeof(ains
->alu
));
1649 *bytes_emitted
+= sizeof(midgard_vector_alu
);
1652 /* Checks for an SSA data hazard between two adjacent instructions, keeping in
1653 * mind that we are a vector architecture and we can write to different
1654 * components simultaneously */
1657 can_run_concurrent_ssa(midgard_instruction
*first
, midgard_instruction
*second
)
1659 /* Each instruction reads some registers and writes to a register. See
1660 * where the first writes */
1662 /* Figure out where exactly we wrote to */
1663 int source
= first
->ssa_args
.dest
;
1664 int source_mask
= first
->type
== TAG_ALU_4
? squeeze_writemask(first
->alu
.mask
) : 0xF;
1666 /* As long as the second doesn't read from the first, we're okay */
1667 if (second
->ssa_args
.src0
== source
) {
1668 if (first
->type
== TAG_ALU_4
) {
1669 /* Figure out which components we just read from */
1671 int q
= second
->alu
.src1
;
1672 midgard_vector_alu_src
*m
= (midgard_vector_alu_src
*) &q
;
1674 /* Check if there are components in common, and fail if so */
1675 if (swizzle_to_access_mask(m
->swizzle
) & source_mask
)
1682 if (second
->ssa_args
.src1
== source
)
1685 /* Otherwise, it's safe in that regard. Another data hazard is both
1686 * writing to the same place, of course */
1688 if (second
->ssa_args
.dest
== source
) {
1689 /* ...but only if the components overlap */
1690 int dest_mask
= second
->type
== TAG_ALU_4
? squeeze_writemask(second
->alu
.mask
) : 0xF;
1692 if (dest_mask
& source_mask
)
1702 midgard_instruction
**segment
, unsigned segment_size
,
1703 midgard_instruction
*ains
)
1705 for (int s
= 0; s
< segment_size
; ++s
)
1706 if (!can_run_concurrent_ssa(segment
[s
], ains
))
1714 /* Schedules, but does not emit, a single basic block. After scheduling, the
1715 * final tag and size of the block are known, which are necessary for branching
1718 static midgard_bundle
1719 schedule_bundle(compiler_context
*ctx
, midgard_block
*block
, midgard_instruction
*ins
, int *skip
)
1721 int instructions_emitted
= 0, instructions_consumed
= -1;
1722 midgard_bundle bundle
= { 0 };
1724 uint8_t tag
= ins
->type
;
1726 /* Default to the instruction's tag */
1729 switch (ins
->type
) {
1731 uint32_t control
= 0;
1732 size_t bytes_emitted
= sizeof(control
);
1734 /* TODO: Constant combining */
1735 int index
= 0, last_unit
= 0;
1737 /* Previous instructions, for the purpose of parallelism */
1738 midgard_instruction
*segment
[4] = {0};
1739 int segment_size
= 0;
1741 instructions_emitted
= -1;
1742 midgard_instruction
*pins
= ins
;
1745 midgard_instruction
*ains
= pins
;
1747 /* Advance instruction pointer */
1749 ains
= mir_next_op(pins
);
1753 /* Out-of-work condition */
1754 if ((struct list_head
*) ains
== &block
->instructions
)
1757 /* Ensure that the chain can continue */
1758 if (ains
->type
!= TAG_ALU_4
) break;
1760 /* If there's already something in the bundle and we
1761 * have weird scheduler constraints, break now */
1762 if (ains
->precede_break
&& index
) break;
1764 /* According to the presentation "The ARM
1765 * Mali-T880 Mobile GPU" from HotChips 27,
1766 * there are two pipeline stages. Branching
1767 * position determined experimentally. Lines
1768 * are executed in parallel:
1771 * [ VADD ] [ SMUL ] [ LUT ] [ BRANCH ]
1773 * Verify that there are no ordering dependencies here.
1775 * TODO: Allow for parallelism!!!
1778 /* Pick a unit for it if it doesn't force a particular unit */
1780 int unit
= ains
->unit
;
1783 int op
= ains
->alu
.op
;
1784 int units
= alu_opcode_props
[op
].props
;
1786 /* TODO: Promotion of scalars to vectors */
1787 int vector
= ((!is_single_component_mask(ains
->alu
.mask
)) || ((units
& UNITS_SCALAR
) == 0)) && (units
& UNITS_ANY_VECTOR
);
1790 assert(units
& UNITS_SCALAR
);
1793 if (last_unit
>= UNIT_VADD
) {
1794 if (units
& UNIT_VLUT
)
1799 if ((units
& UNIT_VMUL
) && !(control
& UNIT_VMUL
))
1801 else if ((units
& UNIT_VADD
) && !(control
& UNIT_VADD
))
1803 else if (units
& UNIT_VLUT
)
1809 if (last_unit
>= UNIT_VADD
) {
1810 if ((units
& UNIT_SMUL
) && !(control
& UNIT_SMUL
))
1812 else if (units
& UNIT_VLUT
)
1817 if ((units
& UNIT_SADD
) && !(control
& UNIT_SADD
) && !midgard_has_hazard(segment
, segment_size
, ains
))
1819 else if (units
& UNIT_SMUL
)
1820 unit
= ((units
& UNIT_VMUL
) && !(control
& UNIT_VMUL
)) ? UNIT_VMUL
: UNIT_SMUL
;
1821 else if ((units
& UNIT_VADD
) && !(control
& UNIT_VADD
))
1828 assert(unit
& units
);
1831 /* Late unit check, this time for encoding (not parallelism) */
1832 if (unit
<= last_unit
) break;
1834 /* Clear the segment */
1835 if (last_unit
< UNIT_VADD
&& unit
>= UNIT_VADD
)
1838 if (midgard_has_hazard(segment
, segment_size
, ains
))
1841 /* We're good to go -- emit the instruction */
1844 segment
[segment_size
++] = ains
;
1846 /* Only one set of embedded constants per
1847 * bundle possible; if we have more, we must
1848 * break the chain early, unfortunately */
1850 if (ains
->has_constants
) {
1851 if (bundle
.has_embedded_constants
) {
1852 /* The blend constant needs to be
1853 * alone, since it conflicts with
1854 * everything by definition*/
1856 if (ains
->has_blend_constant
|| bundle
.has_blend_constant
)
1859 /* ...but if there are already
1860 * constants but these are the
1861 * *same* constants, we let it
1864 if (memcmp(bundle
.constants
, ains
->constants
, sizeof(bundle
.constants
)))
1867 bundle
.has_embedded_constants
= true;
1868 memcpy(bundle
.constants
, ains
->constants
, sizeof(bundle
.constants
));
1870 /* If this is a blend shader special constant, track it for patching */
1871 bundle
.has_blend_constant
|= ains
->has_blend_constant
;
1875 if (ains
->unit
& UNITS_ANY_VECTOR
) {
1876 emit_binary_vector_instruction(ains
, bundle
.register_words
,
1877 &bundle
.register_words_count
, bundle
.body_words
,
1878 bundle
.body_size
, &bundle
.body_words_count
, &bytes_emitted
);
1879 } else if (ains
->compact_branch
) {
1880 /* All of r0 has to be written out
1881 * along with the branch writeout.
1884 if (ains
->writeout
) {
1886 midgard_instruction ins
= v_fmov(0, blank_alu_src
, SSA_FIXED_REGISTER(0));
1887 ins
.unit
= UNIT_VMUL
;
1889 control
|= ins
.unit
;
1891 emit_binary_vector_instruction(&ins
, bundle
.register_words
,
1892 &bundle
.register_words_count
, bundle
.body_words
,
1893 bundle
.body_size
, &bundle
.body_words_count
, &bytes_emitted
);
1895 /* Analyse the group to see if r0 is written in full, on-time, without hanging dependencies*/
1896 bool written_late
= false;
1897 bool components
[4] = { 0 };
1898 uint16_t register_dep_mask
= 0;
1899 uint16_t written_mask
= 0;
1901 midgard_instruction
*qins
= ins
;
1902 for (int t
= 0; t
< index
; ++t
) {
1903 if (qins
->registers
.out_reg
!= 0) {
1904 /* Mark down writes */
1906 written_mask
|= (1 << qins
->registers
.out_reg
);
1908 /* Mark down the register dependencies for errata check */
1910 if (qins
->registers
.src1_reg
< 16)
1911 register_dep_mask
|= (1 << qins
->registers
.src1_reg
);
1913 if (qins
->registers
.src2_reg
< 16)
1914 register_dep_mask
|= (1 << qins
->registers
.src2_reg
);
1916 int mask
= qins
->alu
.mask
;
1918 for (int c
= 0; c
< 4; ++c
)
1919 if (mask
& (0x3 << (2 * c
)))
1920 components
[c
] = true;
1922 /* ..but if the writeout is too late, we have to break up anyway... for some reason */
1924 if (qins
->unit
== UNIT_VLUT
)
1925 written_late
= true;
1928 /* Advance instruction pointer */
1929 qins
= mir_next_op(qins
);
1933 /* ERRATA (?): In a bundle ending in a fragment writeout, the register dependencies of r0 cannot be written within this bundle (discovered in -bshading:shading=phong) */
1934 if (register_dep_mask
& written_mask
) {
1935 DBG("ERRATA WORKAROUND: Breakup for writeout dependency masks %X vs %X (common %X)\n", register_dep_mask
, written_mask
, register_dep_mask
& written_mask
);
1942 /* If even a single component is not written, break it up (conservative check). */
1943 bool breakup
= false;
1945 for (int c
= 0; c
< 4; ++c
)
1952 /* Otherwise, we're free to proceed */
1956 if (ains
->unit
== ALU_ENAB_BRANCH
) {
1957 bundle
.body_size
[bundle
.body_words_count
] = sizeof(midgard_branch_extended
);
1958 memcpy(&bundle
.body_words
[bundle
.body_words_count
++], &ains
->branch_extended
, sizeof(midgard_branch_extended
));
1959 bytes_emitted
+= sizeof(midgard_branch_extended
);
1961 bundle
.body_size
[bundle
.body_words_count
] = sizeof(ains
->br_compact
);
1962 memcpy(&bundle
.body_words
[bundle
.body_words_count
++], &ains
->br_compact
, sizeof(ains
->br_compact
));
1963 bytes_emitted
+= sizeof(ains
->br_compact
);
1966 memcpy(&bundle
.register_words
[bundle
.register_words_count
++], &ains
->registers
, sizeof(ains
->registers
));
1967 bytes_emitted
+= sizeof(midgard_reg_info
);
1969 bundle
.body_size
[bundle
.body_words_count
] = sizeof(midgard_scalar_alu
);
1970 bundle
.body_words_count
++;
1971 bytes_emitted
+= sizeof(midgard_scalar_alu
);
1974 /* Defer marking until after writing to allow for break */
1975 control
|= ains
->unit
;
1976 last_unit
= ains
->unit
;
1977 ++instructions_emitted
;
1981 /* Bubble up the number of instructions for skipping */
1982 instructions_consumed
= index
- 1;
1986 /* Pad ALU op to nearest word */
1988 if (bytes_emitted
& 15) {
1989 padding
= 16 - (bytes_emitted
& 15);
1990 bytes_emitted
+= padding
;
1993 /* Constants must always be quadwords */
1994 if (bundle
.has_embedded_constants
)
1995 bytes_emitted
+= 16;
1997 /* Size ALU instruction for tag */
1998 bundle
.tag
= (TAG_ALU_4
) + (bytes_emitted
/ 16) - 1;
1999 bundle
.padding
= padding
;
2000 bundle
.control
= bundle
.tag
| control
;
2005 case TAG_LOAD_STORE_4
: {
2006 /* Load store instructions have two words at once. If
2007 * we only have one queued up, we need to NOP pad.
2008 * Otherwise, we store both in succession to save space
2009 * and cycles -- letting them go in parallel -- skip
2010 * the next. The usefulness of this optimisation is
2011 * greatly dependent on the quality of the instruction
2015 midgard_instruction
*next_op
= mir_next_op(ins
);
2017 if ((struct list_head
*) next_op
!= &block
->instructions
&& next_op
->type
== TAG_LOAD_STORE_4
) {
2018 /* As the two operate concurrently, make sure
2019 * they are not dependent */
2021 if (can_run_concurrent_ssa(ins
, next_op
) || true) {
2022 /* Skip ahead, since it's redundant with the pair */
2023 instructions_consumed
= 1 + (instructions_emitted
++);
2031 /* Texture ops default to single-op-per-bundle scheduling */
2035 /* Copy the instructions into the bundle */
2036 bundle
.instruction_count
= instructions_emitted
+ 1;
2040 midgard_instruction
*uins
= ins
;
2041 for (int i
= 0; used_idx
< bundle
.instruction_count
; ++i
) {
2042 bundle
.instructions
[used_idx
++] = *uins
;
2043 uins
= mir_next_op(uins
);
2046 *skip
= (instructions_consumed
== -1) ? instructions_emitted
: instructions_consumed
;
2052 quadword_size(int tag
)
2067 case TAG_LOAD_STORE_4
:
2079 /* Schedule a single block by iterating its instruction to create bundles.
2080 * While we go, tally about the bundle sizes to compute the block size. */
2083 schedule_block(compiler_context
*ctx
, midgard_block
*block
)
2085 util_dynarray_init(&block
->bundles
, NULL
);
2087 block
->quadword_count
= 0;
2089 mir_foreach_instr_in_block(block
, ins
) {
2091 midgard_bundle bundle
= schedule_bundle(ctx
, block
, ins
, &skip
);
2092 util_dynarray_append(&block
->bundles
, midgard_bundle
, bundle
);
2094 if (bundle
.has_blend_constant
) {
2095 /* TODO: Multiblock? */
2096 int quadwords_within_block
= block
->quadword_count
+ quadword_size(bundle
.tag
) - 1;
2097 ctx
->blend_constant_offset
= quadwords_within_block
* 0x10;
2101 ins
= mir_next_op(ins
);
2103 block
->quadword_count
+= quadword_size(bundle
.tag
);
2106 block
->is_scheduled
= true;
2110 schedule_program(compiler_context
*ctx
)
2112 /* We run RA prior to scheduling */
2113 struct ra_graph
*g
= allocate_registers(ctx
);
2114 install_registers(ctx
, g
);
2116 mir_foreach_block(ctx
, block
) {
2117 schedule_block(ctx
, block
);
2121 /* After everything is scheduled, emit whole bundles at a time */
2124 emit_binary_bundle(compiler_context
*ctx
, midgard_bundle
*bundle
, struct util_dynarray
*emission
, int next_tag
)
2126 int lookahead
= next_tag
<< 4;
2128 switch (bundle
->tag
) {
2133 /* Actually emit each component */
2134 util_dynarray_append(emission
, uint32_t, bundle
->control
| lookahead
);
2136 for (int i
= 0; i
< bundle
->register_words_count
; ++i
)
2137 util_dynarray_append(emission
, uint16_t, bundle
->register_words
[i
]);
2139 /* Emit body words based on the instructions bundled */
2140 for (int i
= 0; i
< bundle
->instruction_count
; ++i
) {
2141 midgard_instruction
*ins
= &bundle
->instructions
[i
];
2143 if (ins
->unit
& UNITS_ANY_VECTOR
) {
2144 memcpy(util_dynarray_grow(emission
, sizeof(midgard_vector_alu
)), &ins
->alu
, sizeof(midgard_vector_alu
));
2145 } else if (ins
->compact_branch
) {
2146 /* Dummy move, XXX DRY */
2147 if ((i
== 0) && ins
->writeout
) {
2148 midgard_instruction ins
= v_fmov(0, blank_alu_src
, SSA_FIXED_REGISTER(0));
2149 memcpy(util_dynarray_grow(emission
, sizeof(midgard_vector_alu
)), &ins
.alu
, sizeof(midgard_vector_alu
));
2152 if (ins
->unit
== ALU_ENAB_BR_COMPACT
) {
2153 memcpy(util_dynarray_grow(emission
, sizeof(ins
->br_compact
)), &ins
->br_compact
, sizeof(ins
->br_compact
));
2155 memcpy(util_dynarray_grow(emission
, sizeof(ins
->branch_extended
)), &ins
->branch_extended
, sizeof(ins
->branch_extended
));
2159 midgard_scalar_alu scalarised
= vector_to_scalar_alu(ins
->alu
, ins
);
2160 memcpy(util_dynarray_grow(emission
, sizeof(scalarised
)), &scalarised
, sizeof(scalarised
));
2164 /* Emit padding (all zero) */
2165 memset(util_dynarray_grow(emission
, bundle
->padding
), 0, bundle
->padding
);
2167 /* Tack on constants */
2169 if (bundle
->has_embedded_constants
) {
2170 util_dynarray_append(emission
, float, bundle
->constants
[0]);
2171 util_dynarray_append(emission
, float, bundle
->constants
[1]);
2172 util_dynarray_append(emission
, float, bundle
->constants
[2]);
2173 util_dynarray_append(emission
, float, bundle
->constants
[3]);
2179 case TAG_LOAD_STORE_4
: {
2180 /* One or two composing instructions */
2182 uint64_t current64
, next64
= LDST_NOP
;
2184 memcpy(¤t64
, &bundle
->instructions
[0].load_store
, sizeof(current64
));
2186 if (bundle
->instruction_count
== 2)
2187 memcpy(&next64
, &bundle
->instructions
[1].load_store
, sizeof(next64
));
2189 midgard_load_store instruction
= {
2190 .type
= bundle
->tag
,
2191 .next_type
= next_tag
,
2196 util_dynarray_append(emission
, midgard_load_store
, instruction
);
2201 case TAG_TEXTURE_4
: {
2202 /* Texture instructions are easy, since there is no
2203 * pipelining nor VLIW to worry about. We may need to set the .last flag */
2205 midgard_instruction
*ins
= &bundle
->instructions
[0];
2207 ins
->texture
.type
= TAG_TEXTURE_4
;
2208 ins
->texture
.next_type
= next_tag
;
2210 ctx
->texture_op_count
--;
2212 if (!ctx
->texture_op_count
) {
2213 ins
->texture
.cont
= 0;
2214 ins
->texture
.last
= 1;
2217 util_dynarray_append(emission
, midgard_texture_word
, ins
->texture
);
2222 DBG("Unknown midgard instruction type\n");
2229 /* ALU instructions can inline or embed constants, which decreases register
2230 * pressure and saves space. */
2232 #define CONDITIONAL_ATTACH(src) { \
2233 void *entry = _mesa_hash_table_u64_search(ctx->ssa_constants, alu->ssa_args.src + 1); \
2236 attach_constants(ctx, alu, entry, alu->ssa_args.src + 1); \
2237 alu->ssa_args.src = SSA_FIXED_REGISTER(REGISTER_CONSTANT); \
2242 inline_alu_constants(compiler_context
*ctx
)
2244 mir_foreach_instr(ctx
, alu
) {
2245 /* Other instructions cannot inline constants */
2246 if (alu
->type
!= TAG_ALU_4
) continue;
2248 /* If there is already a constant here, we can do nothing */
2249 if (alu
->has_constants
) continue;
2251 /* It makes no sense to inline constants on a branch */
2252 if (alu
->compact_branch
|| alu
->prepacked_branch
) continue;
2254 CONDITIONAL_ATTACH(src0
);
2256 if (!alu
->has_constants
) {
2257 CONDITIONAL_ATTACH(src1
)
2258 } else if (!alu
->inline_constant
) {
2259 /* Corner case: _two_ vec4 constants, for instance with a
2260 * csel. For this case, we can only use a constant
2261 * register for one, we'll have to emit a move for the
2262 * other. Note, if both arguments are constants, then
2263 * necessarily neither argument depends on the value of
2264 * any particular register. As the destination register
2265 * will be wiped, that means we can spill the constant
2266 * to the destination register.
2269 void *entry
= _mesa_hash_table_u64_search(ctx
->ssa_constants
, alu
->ssa_args
.src1
+ 1);
2270 unsigned scratch
= alu
->ssa_args
.dest
;
2273 midgard_instruction ins
= v_fmov(SSA_FIXED_REGISTER(REGISTER_CONSTANT
), blank_alu_src
, scratch
);
2274 attach_constants(ctx
, &ins
, entry
, alu
->ssa_args
.src1
+ 1);
2276 /* Force a break XXX Defer r31 writes */
2277 ins
.unit
= UNIT_VLUT
;
2279 /* Set the source */
2280 alu
->ssa_args
.src1
= scratch
;
2282 /* Inject us -before- the last instruction which set r31 */
2283 mir_insert_instruction_before(mir_prev_op(alu
), ins
);
2289 /* Midgard supports two types of constants, embedded constants (128-bit) and
2290 * inline constants (16-bit). Sometimes, especially with scalar ops, embedded
2291 * constants can be demoted to inline constants, for space savings and
2292 * sometimes a performance boost */
2295 embedded_to_inline_constant(compiler_context
*ctx
)
2297 mir_foreach_instr(ctx
, ins
) {
2298 if (!ins
->has_constants
) continue;
2300 if (ins
->ssa_args
.inline_constant
) continue;
2302 /* Blend constants must not be inlined by definition */
2303 if (ins
->has_blend_constant
) continue;
2305 /* src1 cannot be an inline constant due to encoding
2306 * restrictions. So, if possible we try to flip the arguments
2309 int op
= ins
->alu
.op
;
2311 if (ins
->ssa_args
.src0
== SSA_FIXED_REGISTER(REGISTER_CONSTANT
)) {
2313 /* These ops require an operational change to flip
2314 * their arguments TODO */
2315 case midgard_alu_op_flt
:
2316 case midgard_alu_op_fle
:
2317 case midgard_alu_op_ilt
:
2318 case midgard_alu_op_ile
:
2319 case midgard_alu_op_fcsel
:
2320 case midgard_alu_op_icsel
:
2321 DBG("Missed non-commutative flip (%s)\n", alu_opcode_props
[op
].name
);
2326 if (alu_opcode_props
[op
].props
& OP_COMMUTES
) {
2327 /* Flip the SSA numbers */
2328 ins
->ssa_args
.src0
= ins
->ssa_args
.src1
;
2329 ins
->ssa_args
.src1
= SSA_FIXED_REGISTER(REGISTER_CONSTANT
);
2331 /* And flip the modifiers */
2335 src_temp
= ins
->alu
.src2
;
2336 ins
->alu
.src2
= ins
->alu
.src1
;
2337 ins
->alu
.src1
= src_temp
;
2341 if (ins
->ssa_args
.src1
== SSA_FIXED_REGISTER(REGISTER_CONSTANT
)) {
2342 /* Extract the source information */
2344 midgard_vector_alu_src
*src
;
2345 int q
= ins
->alu
.src2
;
2346 midgard_vector_alu_src
*m
= (midgard_vector_alu_src
*) &q
;
2349 /* Component is from the swizzle, e.g. r26.w -> w component. TODO: What if x is masked out? */
2350 int component
= src
->swizzle
& 3;
2352 /* Scale constant appropriately, if we can legally */
2353 uint16_t scaled_constant
= 0;
2355 if (midgard_is_integer_op(op
)) {
2356 unsigned int *iconstants
= (unsigned int *) ins
->constants
;
2357 scaled_constant
= (uint16_t) iconstants
[component
];
2359 /* Constant overflow after resize */
2360 if (scaled_constant
!= iconstants
[component
])
2363 float original
= (float) ins
->constants
[component
];
2364 scaled_constant
= _mesa_float_to_half(original
);
2366 /* Check for loss of precision. If this is
2367 * mediump, we don't care, but for a highp
2368 * shader, we need to pay attention. NIR
2369 * doesn't yet tell us which mode we're in!
2370 * Practically this prevents most constants
2371 * from being inlined, sadly. */
2373 float fp32
= _mesa_half_to_float(scaled_constant
);
2375 if (fp32
!= original
)
2379 /* We don't know how to handle these with a constant */
2381 if (src
->mod
|| src
->half
|| src
->rep_low
|| src
->rep_high
) {
2382 DBG("Bailing inline constant...\n");
2386 /* Make sure that the constant is not itself a
2387 * vector by checking if all accessed values
2388 * (by the swizzle) are the same. */
2390 uint32_t *cons
= (uint32_t *) ins
->constants
;
2391 uint32_t value
= cons
[component
];
2393 bool is_vector
= false;
2394 unsigned mask
= effective_writemask(&ins
->alu
);
2396 for (int c
= 1; c
< 4; ++c
) {
2397 /* We only care if this component is actually used */
2398 if (!(mask
& (1 << c
)))
2401 uint32_t test
= cons
[(src
->swizzle
>> (2 * c
)) & 3];
2403 if (test
!= value
) {
2412 /* Get rid of the embedded constant */
2413 ins
->has_constants
= false;
2414 ins
->ssa_args
.src1
= SSA_UNUSED_0
;
2415 ins
->ssa_args
.inline_constant
= true;
2416 ins
->inline_constant
= scaled_constant
;
2421 /* Map normal SSA sources to other SSA sources / fixed registers (like
2425 map_ssa_to_alias(compiler_context
*ctx
, int *ref
)
2427 unsigned int alias
= (uintptr_t) _mesa_hash_table_u64_search(ctx
->ssa_to_alias
, *ref
+ 1);
2430 /* Remove entry in leftovers to avoid a redunant fmov */
2432 struct set_entry
*leftover
= _mesa_set_search(ctx
->leftover_ssa_to_alias
, ((void *) (uintptr_t) (*ref
+ 1)));
2435 _mesa_set_remove(ctx
->leftover_ssa_to_alias
, leftover
);
2437 /* Assign the alias map */
2443 /* Basic dead code elimination on the MIR itself, which cleans up e.g. the
2444 * texture pipeline */
2447 midgard_opt_dead_code_eliminate(compiler_context
*ctx
, midgard_block
*block
)
2449 bool progress
= false;
2451 mir_foreach_instr_in_block_safe(block
, ins
) {
2452 if (ins
->type
!= TAG_ALU_4
) continue;
2453 if (ins
->compact_branch
) continue;
2455 if (ins
->ssa_args
.dest
>= SSA_FIXED_MINIMUM
) continue;
2456 if (mir_is_live_after(ctx
, block
, ins
, ins
->ssa_args
.dest
)) continue;
2458 mir_remove_instruction(ins
);
2466 mir_nontrivial_mod(midgard_vector_alu_src src
, bool is_int
, unsigned mask
)
2469 if (!is_int
&& src
.mod
) return true;
2472 for (unsigned c
= 0; c
< 4; ++c
) {
2473 if (!(mask
& (1 << c
))) continue;
2474 if (((src
.swizzle
>> (2*c
)) & 3) != c
) return true;
2481 midgard_opt_copy_prop(compiler_context
*ctx
, midgard_block
*block
)
2483 bool progress
= false;
2485 mir_foreach_instr_in_block_safe(block
, ins
) {
2486 if (ins
->type
!= TAG_ALU_4
) continue;
2487 if (!OP_IS_MOVE(ins
->alu
.op
)) continue;
2489 unsigned from
= ins
->ssa_args
.src1
;
2490 unsigned to
= ins
->ssa_args
.dest
;
2492 /* We only work on pure SSA */
2494 if (to
>= SSA_FIXED_MINIMUM
) continue;
2495 if (from
>= SSA_FIXED_MINIMUM
) continue;
2496 if (to
>= ctx
->func
->impl
->ssa_alloc
) continue;
2497 if (from
>= ctx
->func
->impl
->ssa_alloc
) continue;
2499 /* Constant propagation is not handled here, either */
2500 if (ins
->ssa_args
.inline_constant
) continue;
2501 if (ins
->has_constants
) continue;
2503 /* Also, if the move has side effects, we're helpless */
2505 midgard_vector_alu_src src
=
2506 vector_alu_from_unsigned(ins
->alu
.src2
);
2507 unsigned mask
= squeeze_writemask(ins
->alu
.mask
);
2508 bool is_int
= midgard_is_integer_op(ins
->alu
.op
);
2510 if (mir_nontrivial_mod(src
, is_int
, mask
)) continue;
2511 if (ins
->alu
.outmod
!= midgard_outmod_none
) continue;
2513 mir_foreach_instr_in_block_from(block
, v
, mir_next_op(ins
)) {
2514 if (v
->ssa_args
.src0
== to
) {
2515 v
->ssa_args
.src0
= from
;
2519 if (v
->ssa_args
.src1
== to
&& !v
->ssa_args
.inline_constant
) {
2520 v
->ssa_args
.src1
= from
;
2530 midgard_opt_copy_prop_tex(compiler_context
*ctx
, midgard_block
*block
)
2532 bool progress
= false;
2534 mir_foreach_instr_in_block_safe(block
, ins
) {
2535 if (ins
->type
!= TAG_ALU_4
) continue;
2536 if (!OP_IS_MOVE(ins
->alu
.op
)) continue;
2538 unsigned from
= ins
->ssa_args
.src1
;
2539 unsigned to
= ins
->ssa_args
.dest
;
2541 /* Make sure it's simple enough for us to handle */
2543 if (from
>= SSA_FIXED_MINIMUM
) continue;
2544 if (from
>= ctx
->func
->impl
->ssa_alloc
) continue;
2545 if (to
< SSA_FIXED_REGISTER(REGISTER_TEXTURE_BASE
)) continue;
2546 if (to
> SSA_FIXED_REGISTER(REGISTER_TEXTURE_BASE
+ 1)) continue;
2548 bool eliminated
= false;
2550 mir_foreach_instr_in_block_from_rev(block
, v
, mir_prev_op(ins
)) {
2551 /* The texture registers are not SSA so be careful.
2552 * Conservatively, just stop if we hit a texture op
2553 * (even if it may not write) to where we are */
2555 if (v
->type
!= TAG_ALU_4
)
2558 if (v
->ssa_args
.dest
== from
) {
2559 /* We don't want to track partial writes ... */
2560 if (v
->alu
.mask
== 0xF) {
2561 v
->ssa_args
.dest
= to
;
2570 mir_remove_instruction(ins
);
2572 progress
|= eliminated
;
2578 /* The following passes reorder MIR instructions to enable better scheduling */
2581 midgard_pair_load_store(compiler_context
*ctx
, midgard_block
*block
)
2583 mir_foreach_instr_in_block_safe(block
, ins
) {
2584 if (ins
->type
!= TAG_LOAD_STORE_4
) continue;
2586 /* We've found a load/store op. Check if next is also load/store. */
2587 midgard_instruction
*next_op
= mir_next_op(ins
);
2588 if (&next_op
->link
!= &block
->instructions
) {
2589 if (next_op
->type
== TAG_LOAD_STORE_4
) {
2590 /* If so, we're done since we're a pair */
2591 ins
= mir_next_op(ins
);
2595 /* Maximum search distance to pair, to avoid register pressure disasters */
2596 int search_distance
= 8;
2598 /* Otherwise, we have an orphaned load/store -- search for another load */
2599 mir_foreach_instr_in_block_from(block
, c
, mir_next_op(ins
)) {
2600 /* Terminate search if necessary */
2601 if (!(search_distance
--)) break;
2603 if (c
->type
!= TAG_LOAD_STORE_4
) continue;
2605 /* Stores cannot be reordered, since they have
2606 * dependencies. For the same reason, indirect
2607 * loads cannot be reordered as their index is
2608 * loaded in r27.w */
2610 if (OP_IS_STORE(c
->load_store
.op
)) continue;
2612 /* It appears the 0x800 bit is set whenever a
2613 * load is direct, unset when it is indirect.
2614 * Skip indirect loads. */
2616 if (!(c
->load_store
.unknown
& 0x800)) continue;
2618 /* We found one! Move it up to pair and remove it from the old location */
2620 mir_insert_instruction_before(ins
, *c
);
2621 mir_remove_instruction(c
);
2629 /* Emit varying stores late */
2632 midgard_emit_store(compiler_context
*ctx
, midgard_block
*block
) {
2633 /* Iterate in reverse to get the final write, rather than the first */
2635 mir_foreach_instr_in_block_safe_rev(block
, ins
) {
2636 /* Check if what we just wrote needs a store */
2637 int idx
= ins
->ssa_args
.dest
;
2638 uintptr_t varying
= ((uintptr_t) _mesa_hash_table_u64_search(ctx
->ssa_varyings
, idx
+ 1));
2640 if (!varying
) continue;
2644 /* We need to store to the appropriate varying, so emit the
2647 /* TODO: Integrate with special purpose RA (and scheduler?) */
2648 bool high_varying_register
= false;
2650 midgard_instruction mov
= v_fmov(idx
, blank_alu_src
, SSA_FIXED_REGISTER(REGISTER_VARYING_BASE
+ high_varying_register
));
2652 midgard_instruction st
= m_st_vary_32(SSA_FIXED_REGISTER(high_varying_register
), varying
);
2653 st
.load_store
.unknown
= 0x1E9E; /* XXX: What is this? */
2655 mir_insert_instruction_before(mir_next_op(ins
), st
);
2656 mir_insert_instruction_before(mir_next_op(ins
), mov
);
2658 /* We no longer need to store this varying */
2659 _mesa_hash_table_u64_remove(ctx
->ssa_varyings
, idx
+ 1);
2663 /* If there are leftovers after the below pass, emit actual fmov
2664 * instructions for the slow-but-correct path */
2667 emit_leftover_move(compiler_context
*ctx
)
2669 set_foreach(ctx
->leftover_ssa_to_alias
, leftover
) {
2670 int base
= ((uintptr_t) leftover
->key
) - 1;
2673 map_ssa_to_alias(ctx
, &mapped
);
2674 EMIT(fmov
, mapped
, blank_alu_src
, base
);
2679 actualise_ssa_to_alias(compiler_context
*ctx
)
2681 mir_foreach_instr(ctx
, ins
) {
2682 map_ssa_to_alias(ctx
, &ins
->ssa_args
.src0
);
2683 map_ssa_to_alias(ctx
, &ins
->ssa_args
.src1
);
2686 emit_leftover_move(ctx
);
2690 emit_fragment_epilogue(compiler_context
*ctx
)
2692 /* Special case: writing out constants requires us to include the move
2693 * explicitly now, so shove it into r0 */
2695 void *constant_value
= _mesa_hash_table_u64_search(ctx
->ssa_constants
, ctx
->fragment_output
+ 1);
2697 if (constant_value
) {
2698 midgard_instruction ins
= v_fmov(SSA_FIXED_REGISTER(REGISTER_CONSTANT
), blank_alu_src
, SSA_FIXED_REGISTER(0));
2699 attach_constants(ctx
, &ins
, constant_value
, ctx
->fragment_output
+ 1);
2700 emit_mir_instruction(ctx
, ins
);
2703 /* Perform the actual fragment writeout. We have two writeout/branch
2704 * instructions, forming a loop until writeout is successful as per the
2705 * docs. TODO: gl_FragDepth */
2707 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, 0, midgard_condition_always
);
2708 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, -1, midgard_condition_always
);
2711 /* For the blend epilogue, we need to convert the blended fragment vec4 (stored
2712 * in r0) to a RGBA8888 value by scaling and type converting. We then output it
2713 * with the int8 analogue to the fragment epilogue */
2716 emit_blend_epilogue(compiler_context
*ctx
)
2718 /* vmul.fmul.none.fulllow hr48, r0, #255 */
2720 midgard_instruction scale
= {
2723 .inline_constant
= _mesa_float_to_half(255.0),
2725 .src0
= SSA_FIXED_REGISTER(0),
2726 .src1
= SSA_UNUSED_0
,
2727 .dest
= SSA_FIXED_REGISTER(24),
2728 .inline_constant
= true
2731 .op
= midgard_alu_op_fmul
,
2732 .reg_mode
= midgard_reg_mode_32
,
2733 .dest_override
= midgard_dest_override_lower
,
2735 .src1
= vector_alu_srco_unsigned(blank_alu_src
),
2736 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
2740 emit_mir_instruction(ctx
, scale
);
2742 /* vadd.f2u8.pos.low hr0, hr48, #0 */
2744 midgard_vector_alu_src alu_src
= blank_alu_src
;
2745 alu_src
.half
= true;
2747 midgard_instruction f2u8
= {
2750 .src0
= SSA_FIXED_REGISTER(24),
2751 .src1
= SSA_UNUSED_0
,
2752 .dest
= SSA_FIXED_REGISTER(0),
2753 .inline_constant
= true
2756 .op
= midgard_alu_op_f2u8
,
2757 .reg_mode
= midgard_reg_mode_16
,
2758 .dest_override
= midgard_dest_override_lower
,
2759 .outmod
= midgard_outmod_pos
,
2761 .src1
= vector_alu_srco_unsigned(alu_src
),
2762 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
2766 emit_mir_instruction(ctx
, f2u8
);
2768 /* vmul.imov.quarter r0, r0, r0 */
2770 midgard_instruction imov_8
= {
2773 .src0
= SSA_UNUSED_1
,
2774 .src1
= SSA_FIXED_REGISTER(0),
2775 .dest
= SSA_FIXED_REGISTER(0),
2778 .op
= midgard_alu_op_imov
,
2779 .reg_mode
= midgard_reg_mode_8
,
2780 .dest_override
= midgard_dest_override_none
,
2781 .outmod
= midgard_outmod_int
,
2783 .src1
= vector_alu_srco_unsigned(blank_alu_src
),
2784 .src2
= vector_alu_srco_unsigned(blank_alu_src
),
2788 /* Emit branch epilogue with the 8-bit move as the source */
2790 emit_mir_instruction(ctx
, imov_8
);
2791 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, 0, midgard_condition_always
);
2793 emit_mir_instruction(ctx
, imov_8
);
2794 EMIT(alu_br_compact_cond
, midgard_jmp_writeout_op_writeout
, TAG_ALU_4
, -1, midgard_condition_always
);
2797 static midgard_block
*
2798 emit_block(compiler_context
*ctx
, nir_block
*block
)
2800 midgard_block
*this_block
= calloc(sizeof(midgard_block
), 1);
2801 list_addtail(&this_block
->link
, &ctx
->blocks
);
2803 this_block
->is_scheduled
= false;
2806 ctx
->texture_index
[0] = -1;
2807 ctx
->texture_index
[1] = -1;
2809 /* Add us as a successor to the block we are following */
2810 if (ctx
->current_block
)
2811 midgard_block_add_successor(ctx
->current_block
, this_block
);
2813 /* Set up current block */
2814 list_inithead(&this_block
->instructions
);
2815 ctx
->current_block
= this_block
;
2817 nir_foreach_instr(instr
, block
) {
2818 emit_instr(ctx
, instr
);
2819 ++ctx
->instruction_count
;
2822 inline_alu_constants(ctx
);
2823 embedded_to_inline_constant(ctx
);
2825 /* Perform heavylifting for aliasing */
2826 actualise_ssa_to_alias(ctx
);
2828 midgard_emit_store(ctx
, this_block
);
2829 midgard_pair_load_store(ctx
, this_block
);
2831 /* Append fragment shader epilogue (value writeout) */
2832 if (ctx
->stage
== MESA_SHADER_FRAGMENT
) {
2833 if (block
== nir_impl_last_block(ctx
->func
->impl
)) {
2835 emit_blend_epilogue(ctx
);
2837 emit_fragment_epilogue(ctx
);
2841 if (block
== nir_start_block(ctx
->func
->impl
))
2842 ctx
->initial_block
= this_block
;
2844 if (block
== nir_impl_last_block(ctx
->func
->impl
))
2845 ctx
->final_block
= this_block
;
2847 /* Allow the next control flow to access us retroactively, for
2849 ctx
->current_block
= this_block
;
2851 /* Document the fallthrough chain */
2852 ctx
->previous_source_block
= this_block
;
2857 static midgard_block
*emit_cf_list(struct compiler_context
*ctx
, struct exec_list
*list
);
2860 emit_if(struct compiler_context
*ctx
, nir_if
*nif
)
2862 /* Conditional branches expect the condition in r31.w; emit a move for
2863 * that in the _previous_ block (which is the current block). */
2864 emit_condition(ctx
, &nif
->condition
, true, COMPONENT_X
);
2866 /* Speculatively emit the branch, but we can't fill it in until later */
2867 EMIT(branch
, true, true);
2868 midgard_instruction
*then_branch
= mir_last_in_block(ctx
->current_block
);
2870 /* Emit the two subblocks */
2871 midgard_block
*then_block
= emit_cf_list(ctx
, &nif
->then_list
);
2873 /* Emit a jump from the end of the then block to the end of the else */
2874 EMIT(branch
, false, false);
2875 midgard_instruction
*then_exit
= mir_last_in_block(ctx
->current_block
);
2877 /* Emit second block, and check if it's empty */
2879 int else_idx
= ctx
->block_count
;
2880 int count_in
= ctx
->instruction_count
;
2881 midgard_block
*else_block
= emit_cf_list(ctx
, &nif
->else_list
);
2882 int after_else_idx
= ctx
->block_count
;
2884 /* Now that we have the subblocks emitted, fix up the branches */
2889 if (ctx
->instruction_count
== count_in
) {
2890 /* The else block is empty, so don't emit an exit jump */
2891 mir_remove_instruction(then_exit
);
2892 then_branch
->branch
.target_block
= after_else_idx
;
2894 then_branch
->branch
.target_block
= else_idx
;
2895 then_exit
->branch
.target_block
= after_else_idx
;
2900 emit_loop(struct compiler_context
*ctx
, nir_loop
*nloop
)
2902 /* Remember where we are */
2903 midgard_block
*start_block
= ctx
->current_block
;
2905 /* Allocate a loop number, growing the current inner loop depth */
2906 int loop_idx
= ++ctx
->current_loop_depth
;
2908 /* Get index from before the body so we can loop back later */
2909 int start_idx
= ctx
->block_count
;
2911 /* Emit the body itself */
2912 emit_cf_list(ctx
, &nloop
->body
);
2914 /* Branch back to loop back */
2915 struct midgard_instruction br_back
= v_branch(false, false);
2916 br_back
.branch
.target_block
= start_idx
;
2917 emit_mir_instruction(ctx
, br_back
);
2919 /* Mark down that branch in the graph. Note that we're really branching
2920 * to the block *after* we started in. TODO: Why doesn't the branch
2921 * itself have an off-by-one then...? */
2922 midgard_block_add_successor(ctx
->current_block
, start_block
->successors
[0]);
2924 /* Find the index of the block about to follow us (note: we don't add
2925 * one; blocks are 0-indexed so we get a fencepost problem) */
2926 int break_block_idx
= ctx
->block_count
;
2928 /* Fix up the break statements we emitted to point to the right place,
2929 * now that we can allocate a block number for them */
2931 list_for_each_entry_from(struct midgard_block
, block
, start_block
, &ctx
->blocks
, link
) {
2932 mir_foreach_instr_in_block(block
, ins
) {
2933 if (ins
->type
!= TAG_ALU_4
) continue;
2934 if (!ins
->compact_branch
) continue;
2935 if (ins
->prepacked_branch
) continue;
2937 /* We found a branch -- check the type to see if we need to do anything */
2938 if (ins
->branch
.target_type
!= TARGET_BREAK
) continue;
2940 /* It's a break! Check if it's our break */
2941 if (ins
->branch
.target_break
!= loop_idx
) continue;
2943 /* Okay, cool, we're breaking out of this loop.
2944 * Rewrite from a break to a goto */
2946 ins
->branch
.target_type
= TARGET_GOTO
;
2947 ins
->branch
.target_block
= break_block_idx
;
2951 /* Now that we've finished emitting the loop, free up the depth again
2952 * so we play nice with recursion amid nested loops */
2953 --ctx
->current_loop_depth
;
2956 static midgard_block
*
2957 emit_cf_list(struct compiler_context
*ctx
, struct exec_list
*list
)
2959 midgard_block
*start_block
= NULL
;
2961 foreach_list_typed(nir_cf_node
, node
, node
, list
) {
2962 switch (node
->type
) {
2963 case nir_cf_node_block
: {
2964 midgard_block
*block
= emit_block(ctx
, nir_cf_node_as_block(node
));
2967 start_block
= block
;
2972 case nir_cf_node_if
:
2973 emit_if(ctx
, nir_cf_node_as_if(node
));
2976 case nir_cf_node_loop
:
2977 emit_loop(ctx
, nir_cf_node_as_loop(node
));
2980 case nir_cf_node_function
:
2989 /* Due to lookahead, we need to report the first tag executed in the command
2990 * stream and in branch targets. An initial block might be empty, so iterate
2991 * until we find one that 'works' */
2994 midgard_get_first_tag_from_block(compiler_context
*ctx
, unsigned block_idx
)
2996 midgard_block
*initial_block
= mir_get_block(ctx
, block_idx
);
2998 unsigned first_tag
= 0;
3001 midgard_bundle
*initial_bundle
= util_dynarray_element(&initial_block
->bundles
, midgard_bundle
, 0);
3003 if (initial_bundle
) {
3004 first_tag
= initial_bundle
->tag
;
3008 /* Initial block is empty, try the next block */
3009 initial_block
= list_first_entry(&(initial_block
->link
), midgard_block
, link
);
3010 } while(initial_block
!= NULL
);
3017 midgard_compile_shader_nir(nir_shader
*nir
, midgard_program
*program
, bool is_blend
)
3019 struct util_dynarray
*compiled
= &program
->compiled
;
3021 midgard_debug
= debug_get_option_midgard_debug();
3023 compiler_context ictx
= {
3025 .stage
= nir
->info
.stage
,
3027 .is_blend
= is_blend
,
3028 .blend_constant_offset
= -1,
3030 .alpha_ref
= program
->alpha_ref
3033 compiler_context
*ctx
= &ictx
;
3035 /* TODO: Decide this at runtime */
3036 ctx
->uniform_cutoff
= 8;
3038 /* Assign var locations early, so the epilogue can use them if necessary */
3040 nir_assign_var_locations(&nir
->outputs
, &nir
->num_outputs
, glsl_type_size
);
3041 nir_assign_var_locations(&nir
->inputs
, &nir
->num_inputs
, glsl_type_size
);
3042 nir_assign_var_locations(&nir
->uniforms
, &nir
->num_uniforms
, glsl_type_size
);
3044 /* Initialize at a global (not block) level hash tables */
3046 ctx
->ssa_constants
= _mesa_hash_table_u64_create(NULL
);
3047 ctx
->ssa_varyings
= _mesa_hash_table_u64_create(NULL
);
3048 ctx
->ssa_to_alias
= _mesa_hash_table_u64_create(NULL
);
3049 ctx
->hash_to_temp
= _mesa_hash_table_u64_create(NULL
);
3050 ctx
->sysval_to_id
= _mesa_hash_table_u64_create(NULL
);
3051 ctx
->leftover_ssa_to_alias
= _mesa_set_create(NULL
, _mesa_hash_pointer
, _mesa_key_pointer_equal
);
3053 /* Record the varying mapping for the command stream's bookkeeping */
3055 struct exec_list
*varyings
=
3056 ctx
->stage
== MESA_SHADER_VERTEX
? &nir
->outputs
: &nir
->inputs
;
3058 nir_foreach_variable(var
, varyings
) {
3059 unsigned loc
= var
->data
.driver_location
;
3060 unsigned sz
= glsl_type_size(var
->type
, FALSE
);
3062 for (int c
= 0; c
< sz
; ++c
) {
3063 program
->varyings
[loc
+ c
] = var
->data
.location
;
3067 /* Lower gl_Position pre-optimisation */
3069 if (ctx
->stage
== MESA_SHADER_VERTEX
)
3070 NIR_PASS_V(nir
, nir_lower_viewport_transform
);
3072 NIR_PASS_V(nir
, nir_lower_var_copies
);
3073 NIR_PASS_V(nir
, nir_lower_vars_to_ssa
);
3074 NIR_PASS_V(nir
, nir_split_var_copies
);
3075 NIR_PASS_V(nir
, nir_lower_var_copies
);
3076 NIR_PASS_V(nir
, nir_lower_global_vars_to_local
);
3077 NIR_PASS_V(nir
, nir_lower_var_copies
);
3078 NIR_PASS_V(nir
, nir_lower_vars_to_ssa
);
3080 NIR_PASS_V(nir
, nir_lower_io
, nir_var_all
, glsl_type_size
, 0);
3082 /* Optimisation passes */
3086 if (midgard_debug
& MIDGARD_DBG_SHADERS
) {
3087 nir_print_shader(nir
, stdout
);
3090 /* Assign sysvals and counts, now that we're sure
3091 * (post-optimisation) */
3093 midgard_nir_assign_sysvals(ctx
, nir
);
3095 program
->uniform_count
= nir
->num_uniforms
;
3096 program
->sysval_count
= ctx
->sysval_count
;
3097 memcpy(program
->sysvals
, ctx
->sysvals
, sizeof(ctx
->sysvals
[0]) * ctx
->sysval_count
);
3099 program
->attribute_count
= (ctx
->stage
== MESA_SHADER_VERTEX
) ? nir
->num_inputs
: 0;
3100 program
->varying_count
= (ctx
->stage
== MESA_SHADER_VERTEX
) ? nir
->num_outputs
: ((ctx
->stage
== MESA_SHADER_FRAGMENT
) ? nir
->num_inputs
: 0);
3102 nir_foreach_function(func
, nir
) {
3106 list_inithead(&ctx
->blocks
);
3107 ctx
->block_count
= 0;
3110 emit_cf_list(ctx
, &func
->impl
->body
);
3111 emit_block(ctx
, func
->impl
->end_block
);
3113 break; /* TODO: Multi-function shaders */
3116 util_dynarray_init(compiled
, NULL
);
3118 /* MIR-level optimizations */
3120 bool progress
= false;
3125 mir_foreach_block(ctx
, block
) {
3126 progress
|= midgard_opt_copy_prop(ctx
, block
);
3127 progress
|= midgard_opt_copy_prop_tex(ctx
, block
);
3128 progress
|= midgard_opt_dead_code_eliminate(ctx
, block
);
3133 schedule_program(ctx
);
3135 /* Now that all the bundles are scheduled and we can calculate block
3136 * sizes, emit actual branch instructions rather than placeholders */
3138 int br_block_idx
= 0;
3140 mir_foreach_block(ctx
, block
) {
3141 util_dynarray_foreach(&block
->bundles
, midgard_bundle
, bundle
) {
3142 for (int c
= 0; c
< bundle
->instruction_count
; ++c
) {
3143 midgard_instruction
*ins
= &bundle
->instructions
[c
];
3145 if (!midgard_is_branch_unit(ins
->unit
)) continue;
3147 if (ins
->prepacked_branch
) continue;
3149 /* Parse some basic branch info */
3150 bool is_compact
= ins
->unit
== ALU_ENAB_BR_COMPACT
;
3151 bool is_conditional
= ins
->branch
.conditional
;
3152 bool is_inverted
= ins
->branch
.invert_conditional
;
3153 bool is_discard
= ins
->branch
.target_type
== TARGET_DISCARD
;
3155 /* Determine the block we're jumping to */
3156 int target_number
= ins
->branch
.target_block
;
3158 /* Report the destination tag. Discards don't need this */
3159 int dest_tag
= is_discard
? 0 : midgard_get_first_tag_from_block(ctx
, target_number
);
3161 /* Count up the number of quadwords we're jumping over. That is, the number of quadwords in each of the blocks between (br_block_idx, target_number) */
3162 int quadword_offset
= 0;
3165 /* Jump to the end of the shader. We
3166 * need to include not only the
3167 * following blocks, but also the
3168 * contents of our current block (since
3169 * discard can come in the middle of
3172 midgard_block
*blk
= mir_get_block(ctx
, br_block_idx
+ 1);
3174 for (midgard_bundle
*bun
= bundle
+ 1; bun
< (midgard_bundle
*)((char*) block
->bundles
.data
+ block
->bundles
.size
); ++bun
) {
3175 quadword_offset
+= quadword_size(bun
->tag
);
3178 mir_foreach_block_from(ctx
, blk
, b
) {
3179 quadword_offset
+= b
->quadword_count
;
3182 } else if (target_number
> br_block_idx
) {
3185 for (int idx
= br_block_idx
+ 1; idx
< target_number
; ++idx
) {
3186 midgard_block
*blk
= mir_get_block(ctx
, idx
);
3189 quadword_offset
+= blk
->quadword_count
;
3192 /* Jump backwards */
3194 for (int idx
= br_block_idx
; idx
>= target_number
; --idx
) {
3195 midgard_block
*blk
= mir_get_block(ctx
, idx
);
3198 quadword_offset
-= blk
->quadword_count
;
3202 /* Unconditional extended branches (far jumps)
3203 * have issues, so we always use a conditional
3204 * branch, setting the condition to always for
3205 * unconditional. For compact unconditional
3206 * branches, cond isn't used so it doesn't
3207 * matter what we pick. */
3209 midgard_condition cond
=
3210 !is_conditional
? midgard_condition_always
:
3211 is_inverted
? midgard_condition_false
:
3212 midgard_condition_true
;
3214 midgard_jmp_writeout_op op
=
3215 is_discard
? midgard_jmp_writeout_op_discard
:
3216 (is_compact
&& !is_conditional
) ? midgard_jmp_writeout_op_branch_uncond
:
3217 midgard_jmp_writeout_op_branch_cond
;
3220 midgard_branch_extended branch
=
3221 midgard_create_branch_extended(
3226 memcpy(&ins
->branch_extended
, &branch
, sizeof(branch
));
3227 } else if (is_conditional
|| is_discard
) {
3228 midgard_branch_cond branch
= {
3230 .dest_tag
= dest_tag
,
3231 .offset
= quadword_offset
,
3235 assert(branch
.offset
== quadword_offset
);
3237 memcpy(&ins
->br_compact
, &branch
, sizeof(branch
));
3239 assert(op
== midgard_jmp_writeout_op_branch_uncond
);
3241 midgard_branch_uncond branch
= {
3243 .dest_tag
= dest_tag
,
3244 .offset
= quadword_offset
,
3248 assert(branch
.offset
== quadword_offset
);
3250 memcpy(&ins
->br_compact
, &branch
, sizeof(branch
));
3258 /* Emit flat binary from the instruction arrays. Iterate each block in
3259 * sequence. Save instruction boundaries such that lookahead tags can
3260 * be assigned easily */
3262 /* Cache _all_ bundles in source order for lookahead across failed branches */
3264 int bundle_count
= 0;
3265 mir_foreach_block(ctx
, block
) {
3266 bundle_count
+= block
->bundles
.size
/ sizeof(midgard_bundle
);
3268 midgard_bundle
**source_order_bundles
= malloc(sizeof(midgard_bundle
*) * bundle_count
);
3270 mir_foreach_block(ctx
, block
) {
3271 util_dynarray_foreach(&block
->bundles
, midgard_bundle
, bundle
) {
3272 source_order_bundles
[bundle_idx
++] = bundle
;
3276 int current_bundle
= 0;
3278 mir_foreach_block(ctx
, block
) {
3279 util_dynarray_foreach(&block
->bundles
, midgard_bundle
, bundle
) {
3282 if (current_bundle
+ 1 < bundle_count
) {
3283 uint8_t next
= source_order_bundles
[current_bundle
+ 1]->tag
;
3285 if (!(current_bundle
+ 2 < bundle_count
) && IS_ALU(next
)) {
3292 emit_binary_bundle(ctx
, bundle
, compiled
, lookahead
);
3296 /* TODO: Free deeper */
3297 //util_dynarray_fini(&block->instructions);
3300 free(source_order_bundles
);
3302 /* Report the very first tag executed */
3303 program
->first_tag
= midgard_get_first_tag_from_block(ctx
, 0);
3305 /* Deal with off-by-one related to the fencepost problem */
3306 program
->work_register_count
= ctx
->work_registers
+ 1;
3308 program
->can_discard
= ctx
->can_discard
;
3309 program
->uniform_cutoff
= ctx
->uniform_cutoff
;
3311 program
->blend_patch_offset
= ctx
->blend_constant_offset
;
3313 if (midgard_debug
& MIDGARD_DBG_SHADERS
)
3314 disassemble_midgard(program
->compiled
.data
, program
->compiled
.size
);