1/*
2 * Copyright © 2015 Intel Corporation
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a
5 * copy of this software and associated documentation files (the "Software"),
6 * to deal in the Software without restriction, including without limitation
7 * the rights to use, copy, modify, merge, publish, distribute, sublicense,
8 * and/or sell copies of the Software, and to permit persons to whom the
9 * Software is furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice (including the next
12 * paragraph) shall be included in all copies or substantial portions of the
13 * Software.
14 *
15 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT.  IN NO EVENT SHALL
18 * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20 * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21 * IN THE SOFTWARE.
22 *
23 * Authors:
24 *    Jason Ekstrand (jason@jlekstrand.net)
25 *
26 */
27
28#include <math.h>
29
30#include "nir/nir_builtin_builder.h"
31
32#include "vtn_private.h"
33#include "GLSL.std.450.h"
34
35#define M_PIf   ((float) M_PI)
36#define M_PI_2f ((float) M_PI_2)
37#define M_PI_4f ((float) M_PI_4)
38
39static nir_ssa_def *
40build_mat2_det(nir_builder *b, nir_ssa_def *col[2])
41{
42   unsigned swiz[2] = {1, 0 };
43   nir_ssa_def *p = nir_fmul(b, col[0], nir_swizzle(b, col[1], swiz, 2));
44   return nir_fsub(b, nir_channel(b, p, 0), nir_channel(b, p, 1));
45}
46
47static nir_ssa_def *
48build_mat3_det(nir_builder *b, nir_ssa_def *col[3])
49{
50   unsigned yzx[3] = {1, 2, 0 };
51   unsigned zxy[3] = {2, 0, 1 };
52
53   nir_ssa_def *prod0 =
54      nir_fmul(b, col[0],
55               nir_fmul(b, nir_swizzle(b, col[1], yzx, 3),
56                           nir_swizzle(b, col[2], zxy, 3)));
57   nir_ssa_def *prod1 =
58      nir_fmul(b, col[0],
59               nir_fmul(b, nir_swizzle(b, col[1], zxy, 3),
60                           nir_swizzle(b, col[2], yzx, 3)));
61
62   nir_ssa_def *diff = nir_fsub(b, prod0, prod1);
63
64   return nir_fadd(b, nir_channel(b, diff, 0),
65                      nir_fadd(b, nir_channel(b, diff, 1),
66                                  nir_channel(b, diff, 2)));
67}
68
69static nir_ssa_def *
70build_mat4_det(nir_builder *b, nir_ssa_def **col)
71{
72   nir_ssa_def *subdet[4];
73   for (unsigned i = 0; i < 4; i++) {
74      unsigned swiz[3];
75      for (unsigned j = 0; j < 3; j++)
76         swiz[j] = j + (j >= i);
77
78      nir_ssa_def *subcol[3];
79      subcol[0] = nir_swizzle(b, col[1], swiz, 3);
80      subcol[1] = nir_swizzle(b, col[2], swiz, 3);
81      subcol[2] = nir_swizzle(b, col[3], swiz, 3);
82
83      subdet[i] = build_mat3_det(b, subcol);
84   }
85
86   nir_ssa_def *prod = nir_fmul(b, col[0], nir_vec(b, subdet, 4));
87
88   return nir_fadd(b, nir_fsub(b, nir_channel(b, prod, 0),
89                                  nir_channel(b, prod, 1)),
90                      nir_fsub(b, nir_channel(b, prod, 2),
91                                  nir_channel(b, prod, 3)));
92}
93
94static nir_ssa_def *
95build_mat_det(struct vtn_builder *b, struct vtn_ssa_value *src)
96{
97   unsigned size = glsl_get_vector_elements(src->type);
98
99   nir_ssa_def *cols[4];
100   for (unsigned i = 0; i < size; i++)
101      cols[i] = src->elems[i]->def;
102
103   switch(size) {
104   case 2: return build_mat2_det(&b->nb, cols);
105   case 3: return build_mat3_det(&b->nb, cols);
106   case 4: return build_mat4_det(&b->nb, cols);
107   default:
108      vtn_fail("Invalid matrix size");
109   }
110}
111
112/* Computes the determinate of the submatrix given by taking src and
113 * removing the specified row and column.
114 */
115static nir_ssa_def *
116build_mat_subdet(struct nir_builder *b, struct vtn_ssa_value *src,
117                 unsigned size, unsigned row, unsigned col)
118{
119   assert(row < size && col < size);
120   if (size == 2) {
121      return nir_channel(b, src->elems[1 - col]->def, 1 - row);
122   } else {
123      /* Swizzle to get all but the specified row */
124      unsigned swiz[NIR_MAX_VEC_COMPONENTS] = {0};
125      for (unsigned j = 0; j < 3; j++)
126         swiz[j] = j + (j >= row);
127
128      /* Grab all but the specified column */
129      nir_ssa_def *subcol[3];
130      for (unsigned j = 0; j < size; j++) {
131         if (j != col) {
132            subcol[j - (j > col)] = nir_swizzle(b, src->elems[j]->def,
133                                                swiz, size - 1);
134         }
135      }
136
137      if (size == 3) {
138         return build_mat2_det(b, subcol);
139      } else {
140         assert(size == 4);
141         return build_mat3_det(b, subcol);
142      }
143   }
144}
145
146static struct vtn_ssa_value *
147matrix_inverse(struct vtn_builder *b, struct vtn_ssa_value *src)
148{
149   nir_ssa_def *adj_col[4];
150   unsigned size = glsl_get_vector_elements(src->type);
151
152   /* Build up an adjugate matrix */
153   for (unsigned c = 0; c < size; c++) {
154      nir_ssa_def *elem[4];
155      for (unsigned r = 0; r < size; r++) {
156         elem[r] = build_mat_subdet(&b->nb, src, size, c, r);
157
158         if ((r + c) % 2)
159            elem[r] = nir_fneg(&b->nb, elem[r]);
160      }
161
162      adj_col[c] = nir_vec(&b->nb, elem, size);
163   }
164
165   nir_ssa_def *det_inv = nir_frcp(&b->nb, build_mat_det(b, src));
166
167   struct vtn_ssa_value *val = vtn_create_ssa_value(b, src->type);
168   for (unsigned i = 0; i < size; i++)
169      val->elems[i]->def = nir_fmul(&b->nb, adj_col[i], det_inv);
170
171   return val;
172}
173
174/**
175 * Approximate asin(x) by the piecewise formula:
176 * for |x| < 0.5, asin~(x) = x * (1 + x²(pS0 + x²(pS1 + x²*pS2)) / (1 + x²*qS1))
177 * for |x| ≥ 0.5, asin~(x) = sign(x) * (π/2 - sqrt(1 - |x|) * (π/2 + |x|(π/4 - 1 + |x|(p0 + |x|p1))))
178 *
179 * The latter is correct to first order at x=0 and x=±1 regardless of the p
180 * coefficients but can be made second-order correct at both ends by selecting
181 * the fit coefficients appropriately.  Different p coefficients can be used
182 * in the asin and acos implementation to minimize some relative error metric
183 * in each case.
184 */
185static nir_ssa_def *
186build_asin(nir_builder *b, nir_ssa_def *x, float p0, float p1, bool piecewise)
187{
188   if (x->bit_size == 16) {
189      /* The polynomial approximation isn't precise enough to meet half-float
190       * precision requirements. Alternatively, we could implement this using
191       * the formula:
192       *
193       * asin(x) = atan2(x, sqrt(1 - x*x))
194       *
195       * But that is very expensive, so instead we just do the polynomial
196       * approximation in 32-bit math and then we convert the result back to
197       * 16-bit.
198       */
199      return nir_f2f16(b, build_asin(b, nir_f2f32(b, x), p0, p1, piecewise));
200   }
201   nir_ssa_def *one = nir_imm_floatN_t(b, 1.0f, x->bit_size);
202   nir_ssa_def *half = nir_imm_floatN_t(b, 0.5f, x->bit_size);
203   nir_ssa_def *abs_x = nir_fabs(b, x);
204
205   nir_ssa_def *p0_plus_xp1 = nir_ffma_imm12(b, abs_x, p1, p0);
206
207   nir_ssa_def *expr_tail =
208      nir_ffma_imm2(b, abs_x,
209                       nir_ffma_imm2(b, abs_x, p0_plus_xp1, M_PI_4f - 1.0f),
210                       M_PI_2f);
211
212   nir_ssa_def *result0 = nir_fmul(b, nir_fsign(b, x),
213                      nir_a_minus_bc(b, nir_imm_floatN_t(b, M_PI_2f, x->bit_size),
214                                        nir_fsqrt(b, nir_fsub(b, one, abs_x)),
215                                        expr_tail));
216   if (piecewise) {
217      /* approximation for |x| < 0.5 */
218      const float pS0 =  1.6666586697e-01f;
219      const float pS1 = -4.2743422091e-02f;
220      const float pS2 = -8.6563630030e-03f;
221      const float qS1 = -7.0662963390e-01f;
222
223      nir_ssa_def *x2 = nir_fmul(b, x, x);
224      nir_ssa_def *p = nir_fmul(b,
225                                x2,
226                                nir_ffma_imm2(b, x2,
227                                                 nir_ffma_imm12(b, x2, pS2, pS1),
228                                                 pS0));
229
230      nir_ssa_def *q = nir_ffma_imm1(b, x2, qS1, one);
231      nir_ssa_def *result1 = nir_ffma(b, x, nir_fdiv(b, p, q), x);
232      return nir_bcsel(b, nir_flt(b, abs_x, half), result1, result0);
233   } else {
234      return result0;
235   }
236}
237
238static nir_op
239vtn_nir_alu_op_for_spirv_glsl_opcode(struct vtn_builder *b,
240                                     enum GLSLstd450 opcode,
241                                     unsigned execution_mode,
242                                     bool *exact)
243{
244   *exact = false;
245   switch (opcode) {
246   case GLSLstd450Round:         return nir_op_fround_even;
247   case GLSLstd450RoundEven:     return nir_op_fround_even;
248   case GLSLstd450Trunc:         return nir_op_ftrunc;
249   case GLSLstd450FAbs:          return nir_op_fabs;
250   case GLSLstd450SAbs:          return nir_op_iabs;
251   case GLSLstd450FSign:         return nir_op_fsign;
252   case GLSLstd450SSign:         return nir_op_isign;
253   case GLSLstd450Floor:         return nir_op_ffloor;
254   case GLSLstd450Ceil:          return nir_op_fceil;
255   case GLSLstd450Fract:         return nir_op_ffract;
256   case GLSLstd450Sin:           return nir_op_fsin;
257   case GLSLstd450Cos:           return nir_op_fcos;
258   case GLSLstd450Pow:           return nir_op_fpow;
259   case GLSLstd450Exp2:          return nir_op_fexp2;
260   case GLSLstd450Log2:          return nir_op_flog2;
261   case GLSLstd450Sqrt:          return nir_op_fsqrt;
262   case GLSLstd450InverseSqrt:   return nir_op_frsq;
263   case GLSLstd450NMin:          *exact = true; return nir_op_fmin;
264   case GLSLstd450FMin:          return nir_op_fmin;
265   case GLSLstd450UMin:          return nir_op_umin;
266   case GLSLstd450SMin:          return nir_op_imin;
267   case GLSLstd450NMax:          *exact = true; return nir_op_fmax;
268   case GLSLstd450FMax:          return nir_op_fmax;
269   case GLSLstd450UMax:          return nir_op_umax;
270   case GLSLstd450SMax:          return nir_op_imax;
271   case GLSLstd450FMix:          return nir_op_flrp;
272   case GLSLstd450Fma:           return nir_op_ffma;
273   case GLSLstd450Ldexp:         return nir_op_ldexp;
274   case GLSLstd450FindILsb:      return nir_op_find_lsb;
275   case GLSLstd450FindSMsb:      return nir_op_ifind_msb;
276   case GLSLstd450FindUMsb:      return nir_op_ufind_msb;
277
278   /* Packing/Unpacking functions */
279   case GLSLstd450PackSnorm4x8:     return nir_op_pack_snorm_4x8;
280   case GLSLstd450PackUnorm4x8:     return nir_op_pack_unorm_4x8;
281   case GLSLstd450PackSnorm2x16:    return nir_op_pack_snorm_2x16;
282   case GLSLstd450PackUnorm2x16:    return nir_op_pack_unorm_2x16;
283   case GLSLstd450PackHalf2x16:     return nir_op_pack_half_2x16;
284   case GLSLstd450PackDouble2x32:   return nir_op_pack_64_2x32;
285   case GLSLstd450UnpackSnorm4x8:   return nir_op_unpack_snorm_4x8;
286   case GLSLstd450UnpackUnorm4x8:   return nir_op_unpack_unorm_4x8;
287   case GLSLstd450UnpackSnorm2x16:  return nir_op_unpack_snorm_2x16;
288   case GLSLstd450UnpackUnorm2x16:  return nir_op_unpack_unorm_2x16;
289   case GLSLstd450UnpackHalf2x16:
290      if (execution_mode & FLOAT_CONTROLS_DENORM_FLUSH_TO_ZERO_FP16)
291         return nir_op_unpack_half_2x16_flush_to_zero;
292      else
293         return nir_op_unpack_half_2x16;
294   case GLSLstd450UnpackDouble2x32: return nir_op_unpack_64_2x32;
295
296   default:
297      vtn_fail("No NIR equivalent");
298   }
299}
300
301#define NIR_IMM_FP(n, v) (nir_imm_floatN_t(n, v, src[0]->bit_size))
302
303static void
304handle_glsl450_alu(struct vtn_builder *b, enum GLSLstd450 entrypoint,
305                   const uint32_t *w, unsigned count)
306{
307   struct nir_builder *nb = &b->nb;
308   const struct glsl_type *dest_type = vtn_get_type(b, w[1])->type;
309
310   /* Collect the various SSA sources */
311   unsigned num_inputs = count - 5;
312   nir_ssa_def *src[3] = { NULL, };
313   for (unsigned i = 0; i < num_inputs; i++) {
314      /* These are handled specially below */
315      if (vtn_untyped_value(b, w[i + 5])->value_type == vtn_value_type_pointer)
316         continue;
317
318      src[i] = vtn_get_nir_ssa(b, w[i + 5]);
319   }
320
321   struct vtn_ssa_value *dest = vtn_create_ssa_value(b, dest_type);
322   vtn_handle_no_contraction(b, vtn_untyped_value(b, w[2]));
323   switch (entrypoint) {
324   case GLSLstd450Radians:
325      dest->def = nir_radians(nb, src[0]);
326      break;
327   case GLSLstd450Degrees:
328      dest->def = nir_degrees(nb, src[0]);
329      break;
330   case GLSLstd450Tan:
331      dest->def = nir_ftan(nb, src[0]);
332      break;
333
334   case GLSLstd450Modf: {
335      nir_ssa_def *inf = nir_imm_floatN_t(&b->nb, INFINITY, src[0]->bit_size);
336      nir_ssa_def *sign_bit =
337         nir_imm_intN_t(&b->nb, (uint64_t)1 << (src[0]->bit_size - 1),
338                        src[0]->bit_size);
339      nir_ssa_def *sign = nir_fsign(nb, src[0]);
340      nir_ssa_def *abs = nir_fabs(nb, src[0]);
341
342      /* NaN input should produce a NaN results, and ±Inf input should provide
343       * ±0 result.  The fmul(sign(x), ffract(x)) calculation will already
344       * produce the expected NaN.  To get ±0, directly compare for equality
345       * with Inf instead of using fisfinite (which is false for NaN).
346       */
347      dest->def = nir_bcsel(nb,
348                            nir_ieq(nb, abs, inf),
349                            nir_iand(nb, src[0], sign_bit),
350                            nir_fmul(nb, sign, nir_ffract(nb, abs)));
351
352      struct vtn_pointer *i_ptr = vtn_value(b, w[6], vtn_value_type_pointer)->pointer;
353      struct vtn_ssa_value *whole = vtn_create_ssa_value(b, i_ptr->type->type);
354      whole->def = nir_fmul(nb, sign, nir_ffloor(nb, abs));
355      vtn_variable_store(b, whole, i_ptr, 0);
356      break;
357   }
358
359   case GLSLstd450ModfStruct: {
360      nir_ssa_def *inf = nir_imm_floatN_t(&b->nb, INFINITY, src[0]->bit_size);
361      nir_ssa_def *sign_bit =
362         nir_imm_intN_t(&b->nb, (uint64_t)1 << (src[0]->bit_size - 1),
363                        src[0]->bit_size);
364      nir_ssa_def *sign = nir_fsign(nb, src[0]);
365      nir_ssa_def *abs = nir_fabs(nb, src[0]);
366      vtn_assert(glsl_type_is_struct_or_ifc(dest_type));
367
368      /* See GLSLstd450Modf for explanation of the Inf and NaN handling. */
369      dest->elems[0]->def = nir_bcsel(nb,
370                                      nir_ieq(nb, abs, inf),
371                                      nir_iand(nb, src[0], sign_bit),
372                                      nir_fmul(nb, sign, nir_ffract(nb, abs)));
373      dest->elems[1]->def = nir_fmul(nb, sign, nir_ffloor(nb, abs));
374      break;
375   }
376
377   case GLSLstd450Step: {
378      /* The SPIR-V Extended Instructions for GLSL spec says:
379       *
380       *    Result is 0.0 if x < edge; otherwise result is 1.0.
381       *
382       * Here src[1] is x, and src[0] is edge.  The direct implementation is
383       *
384       *    bcsel(src[1] < src[0], 0.0, 1.0)
385       *
386       * This is effectively b2f(!(src1 < src0)).  Previously this was
387       * implemented using sge(src1, src0), but that produces incorrect
388       * results for NaN.  Instead, we use the identity b2f(!x) = 1 - b2f(x).
389       */
390      const bool exact = nb->exact;
391      nb->exact = true;
392
393      nir_ssa_def *cmp = nir_slt(nb, src[1], src[0]);
394
395      nb->exact = exact;
396      dest->def = nir_fsub(nb, nir_imm_floatN_t(nb, 1.0f, cmp->bit_size), cmp);
397      break;
398   }
399
400   case GLSLstd450Length:
401      dest->def = nir_fast_length(nb, src[0]);
402      break;
403   case GLSLstd450Distance:
404      dest->def = nir_fast_distance(nb, src[0], src[1]);
405      break;
406   case GLSLstd450Normalize:
407      dest->def = nir_fast_normalize(nb, src[0]);
408      break;
409
410   case GLSLstd450Exp:
411      dest->def = nir_fexp(nb, src[0]);
412      break;
413
414   case GLSLstd450Log:
415      dest->def = nir_flog(nb, src[0]);
416      break;
417
418   case GLSLstd450FClamp:
419      dest->def = nir_fclamp(nb, src[0], src[1], src[2]);
420      break;
421   case GLSLstd450NClamp:
422      nb->exact = true;
423      dest->def = nir_fclamp(nb, src[0], src[1], src[2]);
424      nb->exact = false;
425      break;
426   case GLSLstd450UClamp:
427      dest->def = nir_uclamp(nb, src[0], src[1], src[2]);
428      break;
429   case GLSLstd450SClamp:
430      dest->def = nir_iclamp(nb, src[0], src[1], src[2]);
431      break;
432
433   case GLSLstd450Cross: {
434      dest->def = nir_cross3(nb, src[0], src[1]);
435      break;
436   }
437
438   case GLSLstd450SmoothStep: {
439      dest->def = nir_smoothstep(nb, src[0], src[1], src[2]);
440      break;
441   }
442
443   case GLSLstd450FaceForward:
444      dest->def =
445         nir_bcsel(nb, nir_flt(nb, nir_fdot(nb, src[2], src[1]),
446                                   NIR_IMM_FP(nb, 0.0)),
447                       src[0], nir_fneg(nb, src[0]));
448      break;
449
450   case GLSLstd450Reflect:
451      /* I - 2 * dot(N, I) * N */
452      dest->def =
453         nir_a_minus_bc(nb, src[0],
454                            src[1],
455                            nir_fmul(nb, nir_fdot(nb, src[0], src[1]),
456                                         NIR_IMM_FP(nb, 2.0)));
457      break;
458
459   case GLSLstd450Refract: {
460      nir_ssa_def *I = src[0];
461      nir_ssa_def *N = src[1];
462      nir_ssa_def *eta = src[2];
463      nir_ssa_def *n_dot_i = nir_fdot(nb, N, I);
464      nir_ssa_def *one = NIR_IMM_FP(nb, 1.0);
465      nir_ssa_def *zero = NIR_IMM_FP(nb, 0.0);
466      /* According to the SPIR-V and GLSL specs, eta is always a float
467       * regardless of the type of the other operands. However in practice it
468       * seems that if you try to pass it a float then glslang will just
469       * promote it to a double and generate invalid SPIR-V. In order to
470       * support a hypothetical fixed version of glslang we’ll promote eta to
471       * double if the other operands are double also.
472       */
473      if (I->bit_size != eta->bit_size) {
474         nir_op conversion_op =
475            nir_type_conversion_op(nir_type_float | eta->bit_size,
476                                   nir_type_float | I->bit_size,
477                                   nir_rounding_mode_undef);
478         eta = nir_build_alu(nb, conversion_op, eta, NULL, NULL, NULL);
479      }
480      /* k = 1.0 - eta * eta * (1.0 - dot(N, I) * dot(N, I)) */
481      nir_ssa_def *k =
482         nir_a_minus_bc(nb, one, eta,
483                            nir_fmul(nb, eta, nir_a_minus_bc(nb, one, n_dot_i, n_dot_i)));
484      nir_ssa_def *result =
485         nir_a_minus_bc(nb, nir_fmul(nb, eta, I),
486                            nir_ffma(nb, eta, n_dot_i, nir_fsqrt(nb, k)),
487                            N);
488      /* XXX: bcsel, or if statement? */
489      dest->def = nir_bcsel(nb, nir_flt(nb, k, zero), zero, result);
490      break;
491   }
492
493   case GLSLstd450Sinh:
494      /* 0.5 * (e^x - e^(-x)) */
495      dest->def =
496         nir_fmul_imm(nb, nir_fsub(nb, nir_fexp(nb, src[0]),
497                                       nir_fexp(nb, nir_fneg(nb, src[0]))),
498                          0.5f);
499      break;
500
501   case GLSLstd450Cosh:
502      /* 0.5 * (e^x + e^(-x)) */
503      dest->def =
504         nir_fmul_imm(nb, nir_fadd(nb, nir_fexp(nb, src[0]),
505                                       nir_fexp(nb, nir_fneg(nb, src[0]))),
506                          0.5f);
507      break;
508
509   case GLSLstd450Tanh: {
510      /* tanh(x) := (e^x - e^(-x)) / (e^x + e^(-x))
511       *
512       * We clamp x to [-10, +10] to avoid precision problems.  When x > 10,
513       * e^x dominates the sum, e^(-x) is lost and tanh(x) is 1.0 for 32 bit
514       * floating point.
515       *
516       * For 16-bit precision this we clamp x to [-4.2, +4.2].
517       */
518      const uint32_t bit_size = src[0]->bit_size;
519      const double clamped_x = bit_size > 16 ? 10.0 : 4.2;
520      nir_ssa_def *x = nir_fclamp(nb, src[0],
521                                  nir_imm_floatN_t(nb, -clamped_x, bit_size),
522                                  nir_imm_floatN_t(nb, clamped_x, bit_size));
523
524      /* The clamping will filter out NaN values causing an incorrect result.
525       * The comparison is carefully structured to get NaN result for NaN and
526       * get -0 for -0.
527       *
528       *    result = abs(s) > 0.0 ? ... : s;
529       */
530      const bool exact = nb->exact;
531
532      nb->exact = true;
533      nir_ssa_def *is_regular = nir_flt(nb,
534                                        nir_imm_floatN_t(nb, 0, bit_size),
535                                        nir_fabs(nb, src[0]));
536
537      /* The extra 1.0*s ensures that subnormal inputs are flushed to zero
538       * when that is selected by the shader.
539       */
540      nir_ssa_def *flushed = nir_fmul(nb,
541                                      src[0],
542                                      nir_imm_floatN_t(nb, 1.0, bit_size));
543      nb->exact = exact;
544
545      dest->def = nir_bcsel(nb,
546                            is_regular,
547                            nir_fdiv(nb, nir_fsub(nb, nir_fexp(nb, x),
548                                                  nir_fexp(nb, nir_fneg(nb, x))),
549                                     nir_fadd(nb, nir_fexp(nb, x),
550                                              nir_fexp(nb, nir_fneg(nb, x)))),
551                            flushed);
552      break;
553   }
554
555   case GLSLstd450Asinh:
556      dest->def = nir_fmul(nb, nir_fsign(nb, src[0]),
557         nir_flog(nb, nir_fadd(nb, nir_fabs(nb, src[0]),
558                      nir_fsqrt(nb, nir_ffma_imm2(nb, src[0], src[0], 1.0f)))));
559      break;
560   case GLSLstd450Acosh:
561      dest->def = nir_flog(nb, nir_fadd(nb, src[0],
562         nir_fsqrt(nb, nir_ffma_imm2(nb, src[0], src[0], -1.0f))));
563      break;
564   case GLSLstd450Atanh: {
565      nir_ssa_def *one = nir_imm_floatN_t(nb, 1.0, src[0]->bit_size);
566      dest->def =
567         nir_fmul_imm(nb, nir_flog(nb, nir_fdiv(nb, nir_fadd(nb, src[0], one),
568                                       nir_fsub(nb, one, src[0]))),
569                          0.5f);
570      break;
571   }
572
573   case GLSLstd450Asin:
574      dest->def = build_asin(nb, src[0], 0.086566724, -0.03102955, true);
575      break;
576
577   case GLSLstd450Acos:
578      dest->def =
579         nir_fsub(nb, nir_imm_floatN_t(nb, M_PI_2f, src[0]->bit_size),
580                      build_asin(nb, src[0], 0.08132463, -0.02363318, false));
581      break;
582
583   case GLSLstd450Atan:
584      dest->def = nir_atan(nb, src[0]);
585      break;
586
587   case GLSLstd450Atan2:
588      dest->def = nir_atan2(nb, src[0], src[1]);
589      break;
590
591   case GLSLstd450Frexp: {
592      dest->def = nir_frexp_sig(nb, src[0]);
593
594      struct vtn_pointer *i_ptr = vtn_value(b, w[6], vtn_value_type_pointer)->pointer;
595      struct vtn_ssa_value *exp = vtn_create_ssa_value(b, i_ptr->type->type);
596      exp->def = nir_frexp_exp(nb, src[0]);
597      vtn_variable_store(b, exp, i_ptr, 0);
598      break;
599   }
600
601   case GLSLstd450FrexpStruct: {
602      vtn_assert(glsl_type_is_struct_or_ifc(dest_type));
603      dest->elems[0]->def = nir_frexp_sig(nb, src[0]);
604      dest->elems[1]->def = nir_frexp_exp(nb, src[0]);
605      break;
606   }
607
608   default: {
609      unsigned execution_mode =
610         b->shader->info.float_controls_execution_mode;
611      bool exact;
612      nir_op op = vtn_nir_alu_op_for_spirv_glsl_opcode(b, entrypoint, execution_mode, &exact);
613      /* don't override explicit decoration */
614      b->nb.exact |= exact;
615      dest->def = nir_build_alu(&b->nb, op, src[0], src[1], src[2], NULL);
616      break;
617   }
618   }
619   b->nb.exact = false;
620
621   vtn_push_ssa_value(b, w[2], dest);
622}
623
624static void
625handle_glsl450_interpolation(struct vtn_builder *b, enum GLSLstd450 opcode,
626                             const uint32_t *w, unsigned count)
627{
628   nir_intrinsic_op op;
629   switch (opcode) {
630   case GLSLstd450InterpolateAtCentroid:
631      op = nir_intrinsic_interp_deref_at_centroid;
632      break;
633   case GLSLstd450InterpolateAtSample:
634      op = nir_intrinsic_interp_deref_at_sample;
635      break;
636   case GLSLstd450InterpolateAtOffset:
637      op = nir_intrinsic_interp_deref_at_offset;
638      break;
639   default:
640      vtn_fail("Invalid opcode");
641   }
642
643   nir_intrinsic_instr *intrin = nir_intrinsic_instr_create(b->nb.shader, op);
644
645   struct vtn_pointer *ptr =
646      vtn_value(b, w[5], vtn_value_type_pointer)->pointer;
647   nir_deref_instr *deref = vtn_pointer_to_deref(b, ptr);
648
649   /* If the value we are interpolating has an index into a vector then
650    * interpolate the vector and index the result of that instead. This is
651    * necessary because the index will get generated as a series of nir_bcsel
652    * instructions so it would no longer be an input variable.
653    */
654   const bool vec_array_deref = deref->deref_type == nir_deref_type_array &&
655      glsl_type_is_vector(nir_deref_instr_parent(deref)->type);
656
657   nir_deref_instr *vec_deref = NULL;
658   if (vec_array_deref) {
659      vec_deref = deref;
660      deref = nir_deref_instr_parent(deref);
661   }
662   intrin->src[0] = nir_src_for_ssa(&deref->dest.ssa);
663
664   switch (opcode) {
665   case GLSLstd450InterpolateAtCentroid:
666      break;
667   case GLSLstd450InterpolateAtSample:
668   case GLSLstd450InterpolateAtOffset:
669      intrin->src[1] = nir_src_for_ssa(vtn_get_nir_ssa(b, w[6]));
670      break;
671   default:
672      vtn_fail("Invalid opcode");
673   }
674
675   intrin->num_components = glsl_get_vector_elements(deref->type);
676   nir_ssa_dest_init(&intrin->instr, &intrin->dest,
677                     glsl_get_vector_elements(deref->type),
678                     glsl_get_bit_size(deref->type), NULL);
679
680   nir_builder_instr_insert(&b->nb, &intrin->instr);
681
682   nir_ssa_def *def = &intrin->dest.ssa;
683   if (vec_array_deref)
684      def = nir_vector_extract(&b->nb, def, vec_deref->arr.index.ssa);
685
686   vtn_push_nir_ssa(b, w[2], def);
687}
688
689bool
690vtn_handle_glsl450_instruction(struct vtn_builder *b, SpvOp ext_opcode,
691                               const uint32_t *w, unsigned count)
692{
693   switch ((enum GLSLstd450)ext_opcode) {
694   case GLSLstd450Determinant: {
695      vtn_push_nir_ssa(b, w[2], build_mat_det(b, vtn_ssa_value(b, w[5])));
696      break;
697   }
698
699   case GLSLstd450MatrixInverse: {
700      vtn_push_ssa_value(b, w[2], matrix_inverse(b, vtn_ssa_value(b, w[5])));
701      break;
702   }
703
704   case GLSLstd450InterpolateAtCentroid:
705   case GLSLstd450InterpolateAtSample:
706   case GLSLstd450InterpolateAtOffset:
707      handle_glsl450_interpolation(b, (enum GLSLstd450)ext_opcode, w, count);
708      break;
709
710   default:
711      handle_glsl450_alu(b, (enum GLSLstd450)ext_opcode, w, count);
712   }
713
714   return true;
715}
716