diff options
Diffstat (limited to 'src')
| -rw-r--r-- | src/gallium/drivers/vc4/vc4_program.c | 92 |
1 files changed, 91 insertions, 1 deletions
diff --git a/src/gallium/drivers/vc4/vc4_program.c b/src/gallium/drivers/vc4/vc4_program.c index f87a9b21261..cb3ef6e45f3 100644 --- a/src/gallium/drivers/vc4/vc4_program.c +++ b/src/gallium/drivers/vc4/vc4_program.c @@ -43,6 +43,8 @@ static struct qreg ntq_get_src(struct vc4_compile *c, nir_src src, int i); +static void +ntq_emit_cf_list(struct vc4_compile *c, struct exec_list *list); static void resize_qreg_array(struct vc4_compile *c, @@ -1667,10 +1669,98 @@ ntq_emit_intrinsic(struct vc4_compile *c, nir_intrinsic_instr *instr) } } +/* Clears (activates) the execute flags for any channels whose jump target + * matches this block. + */ +static void +ntq_activate_execute_for_block(struct vc4_compile *c) +{ + qir_SF(c, qir_SUB(c, + c->execute, + qir_uniform_ui(c, c->cur_block->index))); + qir_MOV_cond(c, QPU_COND_ZS, c->execute, qir_uniform_ui(c, 0)); +} + static void ntq_emit_if(struct vc4_compile *c, nir_if *if_stmt) { - fprintf(stderr, "general IF statements not handled.\n"); + if (!c->vc4->screen->has_control_flow) { + fprintf(stderr, + "IF statement support requires updated kernel.\n"); + return; + } + + nir_cf_node *nir_first_else_node = nir_if_first_else_node(if_stmt); + nir_cf_node *nir_last_else_node = nir_if_last_else_node(if_stmt); + nir_block *nir_else_block = nir_cf_node_as_block(nir_first_else_node); + bool empty_else_block = + (nir_first_else_node == nir_last_else_node && + exec_list_is_empty(&nir_else_block->instr_list)); + + struct qblock *then_block = qir_new_block(c); + struct qblock *after_block = qir_new_block(c); + struct qblock *else_block; + if (empty_else_block) + else_block = after_block; + else + else_block = qir_new_block(c); + + bool was_top_level = false; + if (c->execute.file == QFILE_NULL) { + c->execute = qir_MOV(c, qir_uniform_ui(c, 0)); + was_top_level = true; + } + + /* Set ZS for executing (execute == 0) and jumping (if->condition == + * 0) channels, and then update execute flags for those to point to + * the ELSE block. + */ + qir_SF(c, qir_OR(c, + c->execute, + ntq_get_src(c, if_stmt->condition, 0))); + qir_MOV_cond(c, QPU_COND_ZS, c->execute, + qir_uniform_ui(c, else_block->index)); + + /* Jump to ELSE if nothing is active for THEN, otherwise fall + * through. + */ + qir_SF(c, c->execute); + qir_BRANCH(c, QPU_COND_BRANCH_ALL_ZC); + qir_link_blocks(c->cur_block, else_block); + qir_link_blocks(c->cur_block, then_block); + + /* Process the THEN block. */ + qir_set_emit_block(c, then_block); + ntq_emit_cf_list(c, &if_stmt->then_list); + + if (!empty_else_block) { + /* Handle the end of the THEN block. First, all currently + * active channels update their execute flags to point to + * ENDIF + */ + qir_SF(c, c->execute); + qir_MOV_cond(c, QPU_COND_ZS, c->execute, + qir_uniform_ui(c, after_block->index)); + + /* If everything points at ENDIF, then jump there immediately. */ + qir_SF(c, qir_SUB(c, c->execute, qir_uniform_ui(c, after_block->index))); + qir_BRANCH(c, QPU_COND_BRANCH_ALL_ZS); + qir_link_blocks(c->cur_block, after_block); + qir_link_blocks(c->cur_block, else_block); + + qir_set_emit_block(c, else_block); + ntq_activate_execute_for_block(c); + ntq_emit_cf_list(c, &if_stmt->else_list); + } + + qir_link_blocks(c->cur_block, after_block); + + qir_set_emit_block(c, after_block); + if (was_top_level) + c->execute = c->undef; + else + ntq_activate_execute_for_block(c); + } static void |