diff options
Diffstat (limited to 'src/shader_recompiler/frontend/maxwell/control_flow.cpp')
| -rw-r--r-- | src/shader_recompiler/frontend/maxwell/control_flow.cpp | 130 |
1 files changed, 124 insertions, 6 deletions
diff --git a/src/shader_recompiler/frontend/maxwell/control_flow.cpp b/src/shader_recompiler/frontend/maxwell/control_flow.cpp index fc4dba826..21ee98137 100644 --- a/src/shader_recompiler/frontend/maxwell/control_flow.cpp +++ b/src/shader_recompiler/frontend/maxwell/control_flow.cpp @@ -36,6 +36,7 @@ static std::array<Block, 2> Split(Block&& block, Location pc, BlockId new_id) { .cond{true}, .branch_true{new_id}, .branch_false{UNREACHABLE_BLOCK_ID}, + .imm_predecessors{}, }, Block{ .begin{pc}, @@ -46,6 +47,7 @@ static std::array<Block, 2> Split(Block&& block, Location pc, BlockId new_id) { .cond{block.cond}, .branch_true{block.branch_true}, .branch_false{block.branch_false}, + .imm_predecessors{}, }, }; } @@ -108,7 +110,7 @@ static bool HasFlowTest(Opcode opcode) { } } -static std::string Name(const Block& block) { +static std::string NameOf(const Block& block) { if (block.begin.IsVirtual()) { return fmt::format("\"Virtual {}\"", block.id); } else { @@ -154,13 +156,127 @@ bool Block::Contains(Location pc) const noexcept { } Function::Function(Location start_address) - : entrypoint{start_address}, labels{Label{ + : entrypoint{start_address}, labels{{ .address{start_address}, .block_id{0}, .stack{}, }} {} +void Function::BuildBlocksMap() { + const size_t num_blocks{NumBlocks()}; + blocks_map.resize(num_blocks); + for (size_t block_index = 0; block_index < num_blocks; ++block_index) { + Block& block{blocks_data[block_index]}; + blocks_map[block.id] = █ + } +} + +void Function::BuildImmediatePredecessors() { + for (const Block& block : blocks_data) { + if (block.branch_true != UNREACHABLE_BLOCK_ID) { + blocks_map[block.branch_true]->imm_predecessors.push_back(block.id); + } + if (block.branch_false != UNREACHABLE_BLOCK_ID) { + blocks_map[block.branch_false]->imm_predecessors.push_back(block.id); + } + } +} + +void Function::BuildPostOrder() { + boost::container::small_vector<BlockId, 0x110> block_stack; + post_order_map.resize(NumBlocks()); + + Block& first_block{blocks_data[blocks.front()]}; + first_block.post_order_visited = true; + block_stack.push_back(first_block.id); + + const auto visit_branch = [&](BlockId block_id, BlockId branch_id) { + if (branch_id == UNREACHABLE_BLOCK_ID) { + return false; + } + if (blocks_map[branch_id]->post_order_visited) { + return false; + } + blocks_map[branch_id]->post_order_visited = true; + + // Calling push_back twice is faster than insert on msvc + block_stack.push_back(block_id); + block_stack.push_back(branch_id); + return true; + }; + while (!block_stack.empty()) { + const Block* const block{blocks_map[block_stack.back()]}; + block_stack.pop_back(); + + if (!visit_branch(block->id, block->branch_true) && + !visit_branch(block->id, block->branch_false)) { + post_order_map[block->id] = static_cast<u32>(post_order_blocks.size()); + post_order_blocks.push_back(block->id); + } + } +} + +void Function::BuildImmediateDominators() { + auto transform_block_id{std::views::transform([this](BlockId id) { return blocks_map[id]; })}; + auto reverse_order_but_first{std::views::reverse | std::views::drop(1) | transform_block_id}; + auto has_idom{std::views::filter([](Block* block) { return block->imm_dominator; })}; + auto intersect{[this](Block* finger1, Block* finger2) { + while (finger1 != finger2) { + while (post_order_map[finger1->id] < post_order_map[finger2->id]) { + finger1 = finger1->imm_dominator; + } + while (post_order_map[finger2->id] < post_order_map[finger1->id]) { + finger2 = finger2->imm_dominator; + } + } + return finger1; + }}; + for (Block& block : blocks_data) { + block.imm_dominator = nullptr; + } + Block* const start_block{&blocks_data[blocks.front()]}; + start_block->imm_dominator = start_block; + + bool changed{true}; + while (changed) { + changed = false; + for (Block* const block : post_order_blocks | reverse_order_but_first) { + Block* new_idom{}; + for (Block* predecessor : block->imm_predecessors | transform_block_id | has_idom) { + new_idom = new_idom ? intersect(predecessor, new_idom) : predecessor; + } + changed |= block->imm_dominator != new_idom; + block->imm_dominator = new_idom; + } + } +} + +void Function::BuildDominanceFrontier() { + auto transform_block_id{std::views::transform([this](BlockId id) { return blocks_map[id]; })}; + auto has_enough_predecessors{[](Block& block) { return block.imm_predecessors.size() >= 2; }}; + for (Block& block : blocks_data | std::views::filter(has_enough_predecessors)) { + for (Block* current : block.imm_predecessors | transform_block_id) { + while (current != block.imm_dominator) { + current->dominance_frontiers.push_back(current->id); + current = current->imm_dominator; + } + } + } +} + CFG::CFG(Environment& env_, Location start_address) : env{env_} { + VisitFunctions(start_address); + + for (Function& function : functions) { + function.BuildBlocksMap(); + function.BuildImmediatePredecessors(); + function.BuildPostOrder(); + function.BuildImmediateDominators(); + function.BuildDominanceFrontier(); + } +} + +void CFG::VisitFunctions(Location start_address) { functions.emplace_back(start_address); for (FunctionId function_id = 0; function_id < functions.size(); ++function_id) { while (!functions[function_id].labels.empty()) { @@ -202,6 +318,7 @@ void CFG::AnalyzeLabel(FunctionId function_id, Label& label) { .cond{true}, .branch_true{UNREACHABLE_BLOCK_ID}, .branch_false{UNREACHABLE_BLOCK_ID}, + .imm_predecessors{}, }; // Analyze instructions until it reaches an already visited block or there's a branch bool is_branch{false}; @@ -310,7 +427,7 @@ CFG::AnalysisState CFG::AnalyzeInst(Block& block, FunctionId function_id, Locati // Technically CAL pushes into PRET, but that's implicit in the function call for us // Insert the function into the list if it doesn't exist if (std::ranges::find(functions, cal_pc, &Function::entrypoint) == functions.end()) { - functions.push_back(cal_pc); + functions.emplace_back(cal_pc); } // Handle CAL like a regular instruction break; @@ -352,6 +469,7 @@ void CFG::AnalyzeCondInst(Block& block, FunctionId function_id, Location pc, .cond{cond}, .branch_true{conditional_block_id}, .branch_false{UNREACHABLE_BLOCK_ID}, + .imm_predecessors{}, })}; // Set the end properties of the conditional instruction and give it a new identity Block& conditional_block{block}; @@ -465,14 +583,14 @@ std::string CFG::Dot() const { dot += fmt::format("\t\tnode [style=filled];\n"); for (const u32 block_index : function.blocks) { const Block& block{function.blocks_data[block_index]}; - const std::string name{Name(block)}; + const std::string name{NameOf(block)}; const auto add_branch = [&](BlockId branch_id, bool add_label) { const auto it{std::ranges::find(function.blocks_data, branch_id, &Block::id)}; dot += fmt::format("\t\t{}->", name); if (it == function.blocks_data.end()) { dot += fmt::format("\"Unknown label {}\"", branch_id); } else { - dot += Name(*it); + dot += NameOf(*it); }; if (add_label && block.cond != true && block.cond != false) { dot += fmt::format(" [label=\"{}\"]", block.cond); @@ -520,7 +638,7 @@ std::string CFG::Dot() const { if (functions.front().blocks.empty()) { dot += "Start;\n"; } else { - dot += fmt::format("\tStart -> {};\n", Name(functions.front().blocks_data.front())); + dot += fmt::format("\tStart -> {};\n", NameOf(functions.front().blocks_data.front())); } dot += fmt::format("\tStart [shape=diamond];\n"); } |