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Diffstat (limited to 'src/compiler/spirv/vtn_cfg.c')
| -rw-r--r-- | src/compiler/spirv/vtn_cfg.c | 778 |
1 files changed, 778 insertions, 0 deletions
diff --git a/src/compiler/spirv/vtn_cfg.c b/src/compiler/spirv/vtn_cfg.c new file mode 100644 index 00000000000..6a43ef8b2dd --- /dev/null +++ b/src/compiler/spirv/vtn_cfg.c @@ -0,0 +1,778 @@ +/* + * Copyright © 2015 Intel Corporation + * + * Permission is hereby granted, free of charge, to any person obtaining a + * copy of this software and associated documentation files (the "Software"), + * to deal in the Software without restriction, including without limitation + * the rights to use, copy, modify, merge, publish, distribute, sublicense, + * and/or sell copies of the Software, and to permit persons to whom the + * Software is furnished to do so, subject to the following conditions: + * + * The above copyright notice and this permission notice (including the next + * paragraph) shall be included in all copies or substantial portions of the + * Software. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR + * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, + * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL + * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER + * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING + * FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS + * IN THE SOFTWARE. + */ + +#include "vtn_private.h" +#include "nir/nir_vla.h" + +static bool +vtn_cfg_handle_prepass_instruction(struct vtn_builder *b, SpvOp opcode, + const uint32_t *w, unsigned count) +{ + switch (opcode) { + case SpvOpFunction: { + assert(b->func == NULL); + b->func = rzalloc(b, struct vtn_function); + + list_inithead(&b->func->body); + b->func->control = w[3]; + + const struct glsl_type *result_type = + vtn_value(b, w[1], vtn_value_type_type)->type->type; + struct vtn_value *val = vtn_push_value(b, w[2], vtn_value_type_function); + val->func = b->func; + + const struct glsl_type *func_type = + vtn_value(b, w[4], vtn_value_type_type)->type->type; + + assert(glsl_get_function_return_type(func_type) == result_type); + + nir_function *func = + nir_function_create(b->shader, ralloc_strdup(b->shader, val->name)); + + func->num_params = glsl_get_length(func_type); + func->params = ralloc_array(b->shader, nir_parameter, func->num_params); + for (unsigned i = 0; i < func->num_params; i++) { + const struct glsl_function_param *param = + glsl_get_function_param(func_type, i); + func->params[i].type = param->type; + if (param->in) { + if (param->out) { + func->params[i].param_type = nir_parameter_inout; + } else { + func->params[i].param_type = nir_parameter_in; + } + } else { + if (param->out) { + func->params[i].param_type = nir_parameter_out; + } else { + assert(!"Parameter is neither in nor out"); + } + } + } + + func->return_type = glsl_get_function_return_type(func_type); + + b->func->impl = nir_function_impl_create(func); + + b->func_param_idx = 0; + break; + } + + case SpvOpFunctionEnd: + b->func->end = w; + b->func = NULL; + break; + + case SpvOpFunctionParameter: { + struct vtn_value *val = + vtn_push_value(b, w[2], vtn_value_type_access_chain); + + struct vtn_type *type = vtn_value(b, w[1], vtn_value_type_type)->type; + + assert(b->func_param_idx < b->func->impl->num_params); + nir_variable *param = b->func->impl->params[b->func_param_idx++]; + + assert(param->type == type->type); + + /* Name the parameter so it shows up nicely in NIR */ + param->name = ralloc_strdup(param, val->name); + + struct vtn_variable *vtn_var = rzalloc(b, struct vtn_variable); + vtn_var->type = type; + vtn_var->var = param; + vtn_var->chain.var = vtn_var; + vtn_var->chain.length = 0; + + struct vtn_type *without_array = type; + while(glsl_type_is_array(without_array->type)) + without_array = without_array->array_element; + + if (glsl_type_is_image(without_array->type)) { + vtn_var->mode = vtn_variable_mode_image; + param->interface_type = without_array->type; + } else if (glsl_type_is_sampler(without_array->type)) { + vtn_var->mode = vtn_variable_mode_sampler; + param->interface_type = without_array->type; + } else { + vtn_var->mode = vtn_variable_mode_param; + } + + val->access_chain = &vtn_var->chain; + break; + } + + case SpvOpLabel: { + assert(b->block == NULL); + b->block = rzalloc(b, struct vtn_block); + b->block->node.type = vtn_cf_node_type_block; + b->block->label = w; + vtn_push_value(b, w[1], vtn_value_type_block)->block = b->block; + + if (b->func->start_block == NULL) { + /* This is the first block encountered for this function. In this + * case, we set the start block and add it to the list of + * implemented functions that we'll walk later. + */ + b->func->start_block = b->block; + exec_list_push_tail(&b->functions, &b->func->node); + } + break; + } + + case SpvOpSelectionMerge: + case SpvOpLoopMerge: + assert(b->block && b->block->merge == NULL); + b->block->merge = w; + break; + + case SpvOpBranch: + case SpvOpBranchConditional: + case SpvOpSwitch: + case SpvOpKill: + case SpvOpReturn: + case SpvOpReturnValue: + case SpvOpUnreachable: + assert(b->block && b->block->branch == NULL); + b->block->branch = w; + b->block = NULL; + break; + + default: + /* Continue on as per normal */ + return true; + } + + return true; +} + +static void +vtn_add_case(struct vtn_builder *b, struct vtn_switch *swtch, + struct vtn_block *break_block, + uint32_t block_id, uint32_t val, bool is_default) +{ + struct vtn_block *case_block = + vtn_value(b, block_id, vtn_value_type_block)->block; + + /* Don't create dummy cases that just break */ + if (case_block == break_block) + return; + + if (case_block->switch_case == NULL) { + struct vtn_case *c = ralloc(b, struct vtn_case); + + list_inithead(&c->body); + c->start_block = case_block; + c->fallthrough = NULL; + nir_array_init(&c->values, b); + c->is_default = false; + c->visited = false; + + list_addtail(&c->link, &swtch->cases); + + case_block->switch_case = c; + } + + if (is_default) { + case_block->switch_case->is_default = true; + } else { + nir_array_add(&case_block->switch_case->values, uint32_t, val); + } +} + +/* This function performs a depth-first search of the cases and puts them + * in fall-through order. + */ +static void +vtn_order_case(struct vtn_switch *swtch, struct vtn_case *cse) +{ + if (cse->visited) + return; + + cse->visited = true; + + list_del(&cse->link); + + if (cse->fallthrough) { + vtn_order_case(swtch, cse->fallthrough); + + /* If we have a fall-through, place this case right before the case it + * falls through to. This ensures that fallthroughs come one after + * the other. These two can never get separated because that would + * imply something else falling through to the same case. Also, this + * can't break ordering because the DFS ensures that this case is + * visited before anything that falls through to it. + */ + list_addtail(&cse->link, &cse->fallthrough->link); + } else { + list_add(&cse->link, &swtch->cases); + } +} + +static enum vtn_branch_type +vtn_get_branch_type(struct vtn_block *block, + struct vtn_case *swcase, struct vtn_block *switch_break, + struct vtn_block *loop_break, struct vtn_block *loop_cont) +{ + if (block->switch_case) { + /* This branch is actually a fallthrough */ + assert(swcase->fallthrough == NULL || + swcase->fallthrough == block->switch_case); + swcase->fallthrough = block->switch_case; + return vtn_branch_type_switch_fallthrough; + } else if (block == switch_break) { + return vtn_branch_type_switch_break; + } else if (block == loop_break) { + return vtn_branch_type_loop_break; + } else if (block == loop_cont) { + return vtn_branch_type_loop_continue; + } else { + return vtn_branch_type_none; + } +} + +static void +vtn_cfg_walk_blocks(struct vtn_builder *b, struct list_head *cf_list, + struct vtn_block *start, struct vtn_case *switch_case, + struct vtn_block *switch_break, + struct vtn_block *loop_break, struct vtn_block *loop_cont, + struct vtn_block *end) +{ + struct vtn_block *block = start; + while (block != end) { + if (block->merge && (*block->merge & SpvOpCodeMask) == SpvOpLoopMerge && + !block->loop) { + struct vtn_loop *loop = ralloc(b, struct vtn_loop); + + loop->node.type = vtn_cf_node_type_loop; + list_inithead(&loop->body); + list_inithead(&loop->cont_body); + loop->control = block->merge[3]; + + list_addtail(&loop->node.link, cf_list); + block->loop = loop; + + struct vtn_block *new_loop_break = + vtn_value(b, block->merge[1], vtn_value_type_block)->block; + struct vtn_block *new_loop_cont = + vtn_value(b, block->merge[2], vtn_value_type_block)->block; + + /* Note: This recursive call will start with the current block as + * its start block. If we weren't careful, we would get here + * again and end up in infinite recursion. This is why we set + * block->loop above and check for it before creating one. This + * way, we only create the loop once and the second call that + * tries to handle this loop goes to the cases below and gets + * handled as a regular block. + * + * Note: When we make the recursive walk calls, we pass NULL for + * the switch break since you have to break out of the loop first. + * We do, however, still pass the current switch case because it's + * possible that the merge block for the loop is the start of + * another case. + */ + vtn_cfg_walk_blocks(b, &loop->body, block, switch_case, NULL, + new_loop_break, new_loop_cont, NULL ); + vtn_cfg_walk_blocks(b, &loop->cont_body, new_loop_cont, NULL, NULL, + new_loop_break, NULL, block); + + block = new_loop_break; + continue; + } + + assert(block->node.link.next == NULL); + list_addtail(&block->node.link, cf_list); + + switch (*block->branch & SpvOpCodeMask) { + case SpvOpBranch: { + struct vtn_block *branch_block = + vtn_value(b, block->branch[1], vtn_value_type_block)->block; + + block->branch_type = vtn_get_branch_type(branch_block, + switch_case, switch_break, + loop_break, loop_cont); + + if (block->branch_type != vtn_branch_type_none) + return; + + block = branch_block; + continue; + } + + case SpvOpReturn: + case SpvOpReturnValue: + block->branch_type = vtn_branch_type_return; + return; + + case SpvOpKill: + block->branch_type = vtn_branch_type_discard; + return; + + case SpvOpBranchConditional: { + struct vtn_block *then_block = + vtn_value(b, block->branch[2], vtn_value_type_block)->block; + struct vtn_block *else_block = + vtn_value(b, block->branch[3], vtn_value_type_block)->block; + + struct vtn_if *if_stmt = ralloc(b, struct vtn_if); + + if_stmt->node.type = vtn_cf_node_type_if; + if_stmt->condition = block->branch[1]; + list_inithead(&if_stmt->then_body); + list_inithead(&if_stmt->else_body); + + list_addtail(&if_stmt->node.link, cf_list); + + if (block->merge && + (*block->merge & SpvOpCodeMask) == SpvOpSelectionMerge) { + if_stmt->control = block->merge[2]; + } + + if_stmt->then_type = vtn_get_branch_type(then_block, + switch_case, switch_break, + loop_break, loop_cont); + if_stmt->else_type = vtn_get_branch_type(else_block, + switch_case, switch_break, + loop_break, loop_cont); + + if (if_stmt->then_type == vtn_branch_type_none && + if_stmt->else_type == vtn_branch_type_none) { + /* Neither side of the if is something we can short-circuit. */ + assert((*block->merge & SpvOpCodeMask) == SpvOpSelectionMerge); + struct vtn_block *merge_block = + vtn_value(b, block->merge[1], vtn_value_type_block)->block; + + vtn_cfg_walk_blocks(b, &if_stmt->then_body, then_block, + switch_case, switch_break, + loop_break, loop_cont, merge_block); + vtn_cfg_walk_blocks(b, &if_stmt->else_body, else_block, + switch_case, switch_break, + loop_break, loop_cont, merge_block); + + enum vtn_branch_type merge_type = + vtn_get_branch_type(merge_block, switch_case, switch_break, + loop_break, loop_cont); + if (merge_type == vtn_branch_type_none) { + block = merge_block; + continue; + } else { + return; + } + } else if (if_stmt->then_type != vtn_branch_type_none && + if_stmt->else_type != vtn_branch_type_none) { + /* Both sides were short-circuited. We're done here. */ + return; + } else { + /* Exeactly one side of the branch could be short-circuited. + * We set the branch up as a predicated break/continue and we + * continue on with the other side as if it were what comes + * after the if. + */ + if (if_stmt->then_type == vtn_branch_type_none) { + block = then_block; + } else { + block = else_block; + } + continue; + } + unreachable("Should have returned or continued"); + } + + case SpvOpSwitch: { + assert((*block->merge & SpvOpCodeMask) == SpvOpSelectionMerge); + struct vtn_block *break_block = + vtn_value(b, block->merge[1], vtn_value_type_block)->block; + + struct vtn_switch *swtch = ralloc(b, struct vtn_switch); + + swtch->node.type = vtn_cf_node_type_switch; + swtch->selector = block->branch[1]; + list_inithead(&swtch->cases); + + list_addtail(&swtch->node.link, cf_list); + + /* First, we go through and record all of the cases. */ + const uint32_t *branch_end = + block->branch + (block->branch[0] >> SpvWordCountShift); + + vtn_add_case(b, swtch, break_block, block->branch[2], 0, true); + for (const uint32_t *w = block->branch + 3; w < branch_end; w += 2) + vtn_add_case(b, swtch, break_block, w[1], w[0], false); + + /* Now, we go through and walk the blocks. While we walk through + * the blocks, we also gather the much-needed fall-through + * information. + */ + list_for_each_entry(struct vtn_case, cse, &swtch->cases, link) { + assert(cse->start_block != break_block); + vtn_cfg_walk_blocks(b, &cse->body, cse->start_block, cse, + break_block, NULL, loop_cont, NULL); + } + + /* Finally, we walk over all of the cases one more time and put + * them in fall-through order. + */ + for (const uint32_t *w = block->branch + 2; w < branch_end; w += 2) { + struct vtn_block *case_block = + vtn_value(b, *w, vtn_value_type_block)->block; + + if (case_block == break_block) + continue; + + assert(case_block->switch_case); + + vtn_order_case(swtch, case_block->switch_case); + } + + block = break_block; + continue; + } + + case SpvOpUnreachable: + return; + + default: + unreachable("Unhandled opcode"); + } + } +} + +void +vtn_build_cfg(struct vtn_builder *b, const uint32_t *words, const uint32_t *end) +{ + vtn_foreach_instruction(b, words, end, + vtn_cfg_handle_prepass_instruction); + + foreach_list_typed(struct vtn_function, func, node, &b->functions) { + vtn_cfg_walk_blocks(b, &func->body, func->start_block, + NULL, NULL, NULL, NULL, NULL); + } +} + +static bool +vtn_handle_phis_first_pass(struct vtn_builder *b, SpvOp opcode, + const uint32_t *w, unsigned count) +{ + if (opcode == SpvOpLabel) + return true; /* Nothing to do */ + + /* If this isn't a phi node, stop. */ + if (opcode != SpvOpPhi) + return false; + + /* For handling phi nodes, we do a poor-man's out-of-ssa on the spot. + * For each phi, we create a variable with the appropreate type and + * do a load from that variable. Then, in a second pass, we add + * stores to that variable to each of the predecessor blocks. + * + * We could do something more intelligent here. However, in order to + * handle loops and things properly, we really need dominance + * information. It would end up basically being the into-SSA + * algorithm all over again. It's easier if we just let + * lower_vars_to_ssa do that for us instead of repeating it here. + */ + struct vtn_value *val = vtn_push_value(b, w[2], vtn_value_type_ssa); + + struct vtn_type *type = vtn_value(b, w[1], vtn_value_type_type)->type; + nir_variable *phi_var = + nir_local_variable_create(b->nb.impl, type->type, "phi"); + _mesa_hash_table_insert(b->phi_table, w, phi_var); + + val->ssa = vtn_local_load(b, nir_deref_var_create(b, phi_var)); + + return true; +} + +static bool +vtn_handle_phi_second_pass(struct vtn_builder *b, SpvOp opcode, + const uint32_t *w, unsigned count) +{ + if (opcode != SpvOpPhi) + return true; + + struct hash_entry *phi_entry = _mesa_hash_table_search(b->phi_table, w); + assert(phi_entry); + nir_variable *phi_var = phi_entry->data; + + for (unsigned i = 3; i < count; i += 2) { + struct vtn_ssa_value *src = vtn_ssa_value(b, w[i]); + struct vtn_block *pred = + vtn_value(b, w[i + 1], vtn_value_type_block)->block; + + b->nb.cursor = nir_after_block_before_jump(pred->end_block); + + vtn_local_store(b, src, nir_deref_var_create(b, phi_var)); + } + + return true; +} + +static void +vtn_emit_branch(struct vtn_builder *b, enum vtn_branch_type branch_type, + nir_variable *switch_fall_var, bool *has_switch_break) +{ + switch (branch_type) { + case vtn_branch_type_switch_break: + nir_store_var(&b->nb, switch_fall_var, nir_imm_int(&b->nb, NIR_FALSE), 1); + *has_switch_break = true; + break; + case vtn_branch_type_switch_fallthrough: + break; /* Nothing to do */ + case vtn_branch_type_loop_break: + nir_jump(&b->nb, nir_jump_break); + break; + case vtn_branch_type_loop_continue: + nir_jump(&b->nb, nir_jump_continue); + break; + case vtn_branch_type_return: + nir_jump(&b->nb, nir_jump_return); + break; + case vtn_branch_type_discard: { + nir_intrinsic_instr *discard = + nir_intrinsic_instr_create(b->nb.shader, nir_intrinsic_discard); + nir_builder_instr_insert(&b->nb, &discard->instr); + break; + } + default: + unreachable("Invalid branch type"); + } +} + +static void +vtn_emit_cf_list(struct vtn_builder *b, struct list_head *cf_list, + nir_variable *switch_fall_var, bool *has_switch_break, + vtn_instruction_handler handler) +{ + list_for_each_entry(struct vtn_cf_node, node, cf_list, link) { + switch (node->type) { + case vtn_cf_node_type_block: { + struct vtn_block *block = (struct vtn_block *)node; + + const uint32_t *block_start = block->label; + const uint32_t *block_end = block->merge ? block->merge : + block->branch; + + block_start = vtn_foreach_instruction(b, block_start, block_end, + vtn_handle_phis_first_pass); + + vtn_foreach_instruction(b, block_start, block_end, handler); + + block->end_block = nir_cursor_current_block(b->nb.cursor); + + if ((*block->branch & SpvOpCodeMask) == SpvOpReturnValue) { + struct vtn_ssa_value *src = vtn_ssa_value(b, block->branch[1]); + vtn_local_store(b, src, + nir_deref_var_create(b, b->impl->return_var)); + } + + if (block->branch_type != vtn_branch_type_none) { + vtn_emit_branch(b, block->branch_type, + switch_fall_var, has_switch_break); + } + + break; + } + + case vtn_cf_node_type_if: { + struct vtn_if *vtn_if = (struct vtn_if *)node; + + nir_if *if_stmt = nir_if_create(b->shader); + if_stmt->condition = + nir_src_for_ssa(vtn_ssa_value(b, vtn_if->condition)->def); + nir_cf_node_insert(b->nb.cursor, &if_stmt->cf_node); + + bool sw_break = false; + + b->nb.cursor = nir_after_cf_list(&if_stmt->then_list); + if (vtn_if->then_type == vtn_branch_type_none) { + vtn_emit_cf_list(b, &vtn_if->then_body, + switch_fall_var, &sw_break, handler); + } else { + vtn_emit_branch(b, vtn_if->then_type, switch_fall_var, &sw_break); + } + + b->nb.cursor = nir_after_cf_list(&if_stmt->else_list); + if (vtn_if->else_type == vtn_branch_type_none) { + vtn_emit_cf_list(b, &vtn_if->else_body, + switch_fall_var, &sw_break, handler); + } else { + vtn_emit_branch(b, vtn_if->else_type, switch_fall_var, &sw_break); + } + + b->nb.cursor = nir_after_cf_node(&if_stmt->cf_node); + + /* If we encountered a switch break somewhere inside of the if, + * then it would have been handled correctly by calling + * emit_cf_list or emit_branch for the interrior. However, we + * need to predicate everything following on wether or not we're + * still going. + */ + if (sw_break) { + *has_switch_break = true; + + nir_if *switch_if = nir_if_create(b->shader); + switch_if->condition = + nir_src_for_ssa(nir_load_var(&b->nb, switch_fall_var)); + nir_cf_node_insert(b->nb.cursor, &switch_if->cf_node); + + b->nb.cursor = nir_after_cf_list(&if_stmt->then_list); + } + break; + } + + case vtn_cf_node_type_loop: { + struct vtn_loop *vtn_loop = (struct vtn_loop *)node; + + nir_loop *loop = nir_loop_create(b->shader); + nir_cf_node_insert(b->nb.cursor, &loop->cf_node); + + b->nb.cursor = nir_after_cf_list(&loop->body); + vtn_emit_cf_list(b, &vtn_loop->body, NULL, NULL, handler); + + if (!list_empty(&vtn_loop->cont_body)) { + /* If we have a non-trivial continue body then we need to put + * it at the beginning of the loop with a flag to ensure that + * it doesn't get executed in the first iteration. + */ + nir_variable *do_cont = + nir_local_variable_create(b->nb.impl, glsl_bool_type(), "cont"); + + b->nb.cursor = nir_before_cf_node(&loop->cf_node); + nir_store_var(&b->nb, do_cont, nir_imm_int(&b->nb, NIR_FALSE), 1); + + b->nb.cursor = nir_before_cf_list(&loop->body); + nir_if *cont_if = nir_if_create(b->shader); + cont_if->condition = nir_src_for_ssa(nir_load_var(&b->nb, do_cont)); + nir_cf_node_insert(b->nb.cursor, &cont_if->cf_node); + + b->nb.cursor = nir_after_cf_list(&cont_if->then_list); + vtn_emit_cf_list(b, &vtn_loop->cont_body, NULL, NULL, handler); + + b->nb.cursor = nir_after_cf_node(&cont_if->cf_node); + nir_store_var(&b->nb, do_cont, nir_imm_int(&b->nb, NIR_TRUE), 1); + + b->has_loop_continue = true; + } + + b->nb.cursor = nir_after_cf_node(&loop->cf_node); + break; + } + + case vtn_cf_node_type_switch: { + struct vtn_switch *vtn_switch = (struct vtn_switch *)node; + + /* First, we create a variable to keep track of whether or not the + * switch is still going at any given point. Any switch breaks + * will set this variable to false. + */ + nir_variable *fall_var = + nir_local_variable_create(b->nb.impl, glsl_bool_type(), "fall"); + nir_store_var(&b->nb, fall_var, nir_imm_int(&b->nb, NIR_FALSE), 1); + + /* Next, we gather up all of the conditions. We have to do this + * up-front because we also need to build an "any" condition so + * that we can use !any for default. + */ + const int num_cases = list_length(&vtn_switch->cases); + NIR_VLA(nir_ssa_def *, conditions, num_cases); + + nir_ssa_def *sel = vtn_ssa_value(b, vtn_switch->selector)->def; + /* An accumulation of all conditions. Used for the default */ + nir_ssa_def *any = NULL; + + int i = 0; + list_for_each_entry(struct vtn_case, cse, &vtn_switch->cases, link) { + if (cse->is_default) { + conditions[i++] = NULL; + continue; + } + + nir_ssa_def *cond = NULL; + nir_array_foreach(&cse->values, uint32_t, val) { + nir_ssa_def *is_val = + nir_ieq(&b->nb, sel, nir_imm_int(&b->nb, *val)); + + cond = cond ? nir_ior(&b->nb, cond, is_val) : is_val; + } + + any = any ? nir_ior(&b->nb, any, cond) : cond; + conditions[i++] = cond; + } + assert(i == num_cases); + + /* Now we can walk the list of cases and actually emit code */ + i = 0; + list_for_each_entry(struct vtn_case, cse, &vtn_switch->cases, link) { + /* Figure out the condition */ + nir_ssa_def *cond = conditions[i++]; + if (cse->is_default) { + assert(cond == NULL); + cond = nir_inot(&b->nb, any); + } + /* Take fallthrough into account */ + cond = nir_ior(&b->nb, cond, nir_load_var(&b->nb, fall_var)); + + nir_if *case_if = nir_if_create(b->nb.shader); + case_if->condition = nir_src_for_ssa(cond); + nir_cf_node_insert(b->nb.cursor, &case_if->cf_node); + + bool has_break = false; + b->nb.cursor = nir_after_cf_list(&case_if->then_list); + nir_store_var(&b->nb, fall_var, nir_imm_int(&b->nb, NIR_TRUE), 1); + vtn_emit_cf_list(b, &cse->body, fall_var, &has_break, handler); + (void)has_break; /* We don't care */ + + b->nb.cursor = nir_after_cf_node(&case_if->cf_node); + } + assert(i == num_cases); + + break; + } + + default: + unreachable("Invalid CF node type"); + } + } +} + +void +vtn_function_emit(struct vtn_builder *b, struct vtn_function *func, + vtn_instruction_handler instruction_handler) +{ + nir_builder_init(&b->nb, func->impl); + b->nb.cursor = nir_after_cf_list(&func->impl->body); + b->has_loop_continue = false; + b->phi_table = _mesa_hash_table_create(b, _mesa_hash_pointer, + _mesa_key_pointer_equal); + + vtn_emit_cf_list(b, &func->body, NULL, NULL, instruction_handler); + + vtn_foreach_instruction(b, func->start_block->label, func->end, + vtn_handle_phi_second_pass); + + /* Continue blocks for loops get inserted before the body of the loop + * but instructions in the continue may use SSA defs in the loop body. + * Therefore, we need to repair SSA to insert the needed phi nodes. + */ + if (b->has_loop_continue) + nir_repair_ssa_impl(func->impl); +} |