shader_recompiler: add SSA

src/graphics/shader/recompiler/ir/Block.cpp

@@ -0,0 +1,84 @@
+#include "graphics/shader/recompiler/ir/Block.h"
+
+#include <algorithm>
+#include <limits>
+
+namespace Libs::Graphics::ShaderRecompiler::IR {
+
+Block::~Block() {
+	// Instructions own reverse-use links. Unlink every argument while all definitions are still
+	// alive, then let the list destroy the detached instructions.
+	for (auto& inst: instructions) {
+		inst.Invalidate();
+	}
+}
+
+Inst& Block::AppendNewInst(ValueOpcode opcode, std::initializer_list<Value> args, uint64_t flags) {
+	return *PrependNewInst(end(), opcode, args, flags);
+}
+
+Block::iterator Block::PrependNewInst(iterator insertion_point, ValueOpcode opcode,
+                                      std::initializer_list<Value> args, uint64_t flags) {
+	const auto expected = NumArgsOf(opcode);
+	EXIT_IF(expected != std::numeric_limits<size_t>::max() && expected != args.size());
+	const auto inst = instructions.emplace(insertion_point, opcode, flags);
+	inst->SetParent(this);
+	size_t index = 0;
+	for (const auto arg: args) {
+		inst->SetArg(index++, arg);
+	}
+	return inst;
+}
+
+void Block::AddBranch(Block* block) {
+	EXIT_IF(block == nullptr || std::ranges::find(successors, block) != successors.end());
+	EXIT_IF(std::ranges::find(block->predecessors, this) != block->predecessors.end());
+	successors.push_back(block);
+	block->predecessors.push_back(this);
+}
+
+Block::InstructionList& Block::Instructions() {
+	return instructions;
+}
+
+const Block::InstructionList& Block::Instructions() const {
+	return instructions;
+}
+
+std::span<Block* const> Block::ImmPredecessors() const {
+	return predecessors;
+}
+
+std::span<Block* const> Block::ImmSuccessors() const {
+	return successors;
+}
+
+void Block::SsaSeal() {
+	ssa_sealed = true;
+}
+
+bool Block::IsSsaSealed() const {
+	return ssa_sealed;
+}
+
+Block::iterator Block::begin() {
+	return instructions.begin();
+}
+
+Block::const_iterator Block::begin() const {
+	return instructions.begin();
+}
+
+Block::iterator Block::end() {
+	return instructions.end();
+}
+
+Block::const_iterator Block::end() const {
+	return instructions.end();
+}
+
+bool Block::empty() const {
+	return instructions.empty();
+}
+
+} // namespace Libs::Graphics::ShaderRecompiler::IR