From 134b5a7047f97fbf2537c5e4f31fa08264e1c130 Mon Sep 17 00:00:00 2001 From: Caio Marcelo de Oliveira Filho Date: Wed, 27 Jun 2018 14:39:54 -0700 Subject: [PATCH] glsl: teach copy_propagation_elements to deal with whole variables Keep information in acp_entry whether the entry is full or not, and use the ACP in more nodes when visiting the instructions: - add_copy: write whole variables to the ACP state (regardless the type). - visit(ir_dereference_variable *): perform the propagation here if we have a full candidate. Element-wise here doesn't apply because the mask isn't available at this point. - visit_leave(ir_assignment *): process beyond scalar and vector, as the full variables might have other types. Also import an improvement from opt_copy_propagation.cpp: if ir_call is an intrinsic, we know the variables affected, so keep going. v2: (all from Eric Anholt) Describe how acp_entry attributes are used. Don't do book-keeping to avoid adding repeated element to the dsts in write_elements(). v3: Use _mesa_set_remove_key. (Thomas Helland) Reviewed-by: Eric Anholt Reviewed-by: Thomas Helland --- .../glsl/opt_copy_propagation_elements.cpp | 147 ++++++++++++++---- 1 file changed, 118 insertions(+), 29 deletions(-) diff --git a/src/compiler/glsl/opt_copy_propagation_elements.cpp b/src/compiler/glsl/opt_copy_propagation_elements.cpp index 4c6ca790394..cd55c54ec0e 100644 --- a/src/compiler/glsl/opt_copy_propagation_elements.cpp +++ b/src/compiler/glsl/opt_copy_propagation_elements.cpp @@ -27,18 +27,9 @@ * Replaces usage of recently-copied components of variables with the * previous copy of the variable. * - * This pass can be compared with opt_copy_propagation, which operands - * on arbitrary whole-variable copies. However, in order to handle - * the copy propagation of swizzled variables or writemasked writes, - * we want to track things on a channel-wise basis. I found that - * trying to mix the swizzled/writemasked support here with the - * whole-variable stuff in opt_copy_propagation.cpp just made a mess, - * so this is separate despite the ACP handling being somewhat - * similar. - * * This should reduce the number of MOV instructions in the generated - * programs unless copy propagation is also done on the LIR, and may - * help anyway by triggering other optimizations that live in the HIR. + * programs and help triggering other optimizations that live in GLSL + * level. */ #include "ir.h" @@ -58,9 +49,22 @@ class acp_entry public: DECLARE_LINEAR_ZALLOC_CXX_OPERATORS(acp_entry) + /* If set, rhs_full indicates that this ACP entry represents a + * whole-variable copy. The rhs_element[] array will still be filled, + * to allow the swizzling from its components in case the variable + * was a vector (and to simplify some of the erase() and write_vector() + * logic). + */ + + ir_variable *rhs_full; ir_variable *rhs_element[4]; unsigned rhs_channel[4]; + /* Set of variables that use the variable associated with this acp_entry as + * RHS. This has the "reverse references" of rhs_full/rhs_element. It is + * used to speed up invalidating those references when the acp_entry + * changes. + */ set *dsts; }; @@ -91,6 +95,7 @@ public: void erase(ir_variable *var, unsigned write_mask) { acp_entry *entry = pull_acp(var); + entry->rhs_full = NULL; for (int i = 0; i < 4; i++) { if (!entry->rhs_element[i]) @@ -114,6 +119,8 @@ public: if (dst_entry->rhs_element[i] == var) dst_entry->rhs_element[i] = NULL; } + if (dst_entry->rhs_full == var) + dst_entry->rhs_full = NULL; _mesa_set_remove(entry->dsts, set_entry); } } @@ -128,9 +135,10 @@ public: return NULL; } - void write(ir_variable *lhs, ir_variable *rhs, unsigned write_mask, int swizzle[4]) + void write_elements(ir_variable *lhs, ir_variable *rhs, unsigned write_mask, int swizzle[4]) { acp_entry *lhs_entry = pull_acp(lhs); + lhs_entry->rhs_full = NULL; for (int i = 0; i < 4; i++) { if ((write_mask & (1 << i)) == 0) @@ -146,6 +154,33 @@ public: _mesa_set_add(rhs_entry->dsts, lhs); } + void write_full(ir_variable *lhs, ir_variable *rhs) + { + acp_entry *lhs_entry = pull_acp(lhs); + if (lhs_entry->rhs_full == rhs) + return; + + if (lhs_entry->rhs_full) { + remove_from_dsts(lhs_entry->rhs_full, lhs); + } else if (lhs->type->is_vector()) { + for (int i = 0; i < 4; i++) { + if (lhs_entry->rhs_element[i]) + remove_from_dsts(lhs_entry->rhs_element[i], lhs); + } + } + + lhs_entry->rhs_full = rhs; + acp_entry *rhs_entry = pull_acp(rhs); + _mesa_set_add(rhs_entry->dsts, lhs); + + if (lhs->type->is_vector()) { + for (int i = 0; i < 4; i++) { + lhs_entry->rhs_element[i] = rhs; + lhs_entry->rhs_channel[i] = i; + } + } + } + void remove_unused_var_from_dsts(acp_entry *lhs_entry, ir_variable *lhs, ir_variable *var) { if (!var) @@ -204,6 +239,14 @@ private: return entry; } + void + remove_from_dsts(ir_variable *var, ir_variable *to_remove) + { + acp_entry *entry = pull_acp(var); + assert(entry); + _mesa_set_remove_key(entry->dsts, to_remove); + } + /** Available Copy to Propagate table, from variable to the entry * containing the current sources that can be used. */ hash_table *acp; @@ -247,6 +290,8 @@ public: ralloc_free(mem_ctx); } + virtual ir_visitor_status visit(ir_dereference_variable *); + void handle_loop(ir_loop *, bool keep_acp); virtual ir_visitor_status visit_enter(class ir_loop *); virtual ir_visitor_status visit_enter(class ir_function_signature *); @@ -282,6 +327,21 @@ public: } /* unnamed namespace */ +ir_visitor_status +ir_copy_propagation_elements_visitor::visit(ir_dereference_variable *ir) +{ + if (this->in_assignee) + return visit_continue; + + const acp_entry *entry = state->read(ir->var); + if (entry && entry->rhs_full) { + ir->var = (ir_variable *) entry->rhs_full; + progress = true; + } + + return visit_continue; +} + ir_visitor_status ir_copy_propagation_elements_visitor::visit_enter(ir_function_signature *ir) { @@ -316,16 +376,14 @@ ir_copy_propagation_elements_visitor::visit_leave(ir_assignment *ir) ir_dereference_variable *lhs = ir->lhs->as_dereference_variable(); ir_variable *var = ir->lhs->variable_referenced(); - if (var->type->is_scalar() || var->type->is_vector()) { - kill_entry *k; + kill_entry *k; - if (lhs) - k = new(this->lin_ctx) kill_entry(var, ir->write_mask); - else - k = new(this->lin_ctx) kill_entry(var, ~0); + if (lhs && var->type->is_vector()) + k = new(this->lin_ctx) kill_entry(var, ir->write_mask); + else + k = new(this->lin_ctx) kill_entry(var, ~0); - kill(k); - } + kill(k); add_copy(ir); @@ -460,11 +518,25 @@ ir_copy_propagation_elements_visitor::visit_enter(ir_call *ir) } } - /* Since we're unlinked, we don't (necessarily) know the side effects of - * this call. So kill all copies. - */ - this->state->erase_all(); - this->killed_all = true; + if (!ir->callee->is_intrinsic()) { + state->erase_all(); + this->killed_all = true; + } else { + if (ir->return_deref) { + kill(new(this->lin_ctx) kill_entry(ir->return_deref->var, ~0)); + } + + foreach_two_lists(formal_node, &ir->callee->parameters, + actual_node, &ir->actual_parameters) { + ir_variable *sig_param = (ir_variable *) formal_node; + if (sig_param->data.mode == ir_var_function_out || + sig_param->data.mode == ir_var_function_inout) { + ir_rvalue *ir = (ir_rvalue *) actual_node; + ir_variable *var = ir->variable_referenced(); + kill(new(this->lin_ctx) kill_entry(var, ~0)); + } + } + } return visit_continue_with_parent; } @@ -585,12 +657,29 @@ ir_copy_propagation_elements_visitor::kill(kill_entry *k) void ir_copy_propagation_elements_visitor::add_copy(ir_assignment *ir) { - int orig_swizzle[4] = {0, 1, 2, 3}; - int swizzle[4]; - if (ir->condition) return; + { + ir_variable *lhs_var = ir->whole_variable_written(); + ir_dereference_variable *rhs = ir->rhs->as_dereference_variable(); + + if (lhs_var != NULL && rhs && rhs->var != NULL && lhs_var != rhs->var) { + if (lhs_var->data.mode == ir_var_shader_storage || + lhs_var->data.mode == ir_var_shader_shared || + rhs->var->data.mode == ir_var_shader_storage || + rhs->var->data.mode == ir_var_shader_shared || + lhs_var->data.precise != rhs->var->data.precise) { + return; + } + state->write_full(lhs_var, rhs->var); + return; + } + } + + int orig_swizzle[4] = {0, 1, 2, 3}; + int swizzle[4]; + ir_dereference_variable *lhs = ir->lhs->as_dereference_variable(); if (!lhs || !(lhs->type->is_scalar() || lhs->type->is_vector())) return; @@ -645,7 +734,7 @@ ir_copy_propagation_elements_visitor::add_copy(ir_assignment *ir) if (lhs->var->data.precise != rhs->var->data.precise) return; - state->write(lhs->var, rhs->var, write_mask, swizzle); + state->write_elements(lhs->var, rhs->var, write_mask, swizzle); } bool -- 2.30.2