[CodeGen] Generate RISC-V macro fusion rules

1 files changed, 100 insertions, 0 deletions

diff --git a/backend/utils/TableGen/MacroFusionEmitter.cpp b/backend/utils/TableGen/MacroFusionEmitter.cpp
new file mode 100644
index 0000000..2018a43
--- /dev/null
+++ b/backend/utils/TableGen/MacroFusionEmitter.cpp
@@ -0,0 +1,100 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "TableGenBackends.h"
+
+#include <cstddef>
+#include <cstdint>
+#include <ostream>
+#include <sstream>
+#include <string>
+#include <string_view>
+
+namespace rcc::targetgen {
+namespace {
+
+[[nodiscard]] std::string_view
+instructionSide(NormalizedMacroFusionInstruction Instruction) noexcept {
+  return Instruction == NormalizedMacroFusionInstruction::First ? "First" : "Second";
+}
+
+void emitOpcodes(std::ostream &Output, const NormalizedMacroFusionRule &Rule,
+                 std::string_view Suffix, const std::vector<std::uint32_t> &Opcodes) {
+  Output << "constexpr std::array<Opcode, " << Opcodes.size() << "> " << Rule.Symbol << Suffix
+         << " = {{\n";
+  for (const std::uint32_t Opcode : Opcodes)
+    Output << "    Opcode::fromValue(" << Opcode << "),\n";
+  Output << "}};\n";
+}
+
+} // namespace
+
+std::string emitMacroFusion(const NormalizedTargetModel &Model, std::string_view SourceName) {
+  std::ostringstream Output;
+  Output << "// SPDX-License-Identifier: GPL-3.0-or-later\n\n";
+  Output << "// This file is generated by rcc-tblgen from ";
+  appendQuoted(Output, SourceName);
+  Output << ". Do not edit it manually.\n\n";
+  Output << "#ifdef GET_MACRO_FUSION_RULES\n\n";
+  for (const NormalizedMacroFusionRule &Rule : Model.MacroFusionRules) {
+    emitOpcodes(Output, Rule, "FirstOpcodes", Rule.FirstOpcodes);
+    emitOpcodes(Output, Rule, "SecondOpcodes", Rule.SecondOpcodes);
+    Output << "constexpr std::array<MacroFusionOpcodePair, " << Rule.OpcodePairs.size() << "> "
+           << Rule.Symbol << "OpcodePairs = {{\n";
+    for (const NormalizedMacroFusionOpcodePair &Pair : Rule.OpcodePairs) {
+      Output << "    {Opcode::fromValue(" << Pair.FirstOpcode << "), Opcode::fromValue("
+             << Pair.SecondOpcode << ")},\n";
+    }
+    Output << "}};\n";
+    Output << "constexpr std::array<MacroFusionImmediatePredicate, "
+           << Rule.ImmediatePredicates.size() << "> " << Rule.Symbol
+           << "ImmediatePredicates = {{\n";
+    for (const NormalizedMacroFusionImmediatePredicate &Predicate : Rule.ImmediatePredicates) {
+      Output << "    {MacroFusionInstruction::" << instructionSide(Predicate.Instruction) << ", "
+             << Predicate.OperandIndex << ", " << Predicate.Minimum << ", " << Predicate.Maximum
+             << "},\n";
+    }
+    Output << "}};\n";
+    Output << "constexpr std::array<MacroFusionRegisterInequality, "
+           << Rule.RegisterInequalities.size() << "> " << Rule.Symbol
+           << "RegisterInequalities = {{\n";
+    for (const NormalizedMacroFusionRegisterInequality &Predicate : Rule.RegisterInequalities) {
+      Output << "    {MacroFusionInstruction::" << instructionSide(Predicate.Instruction) << ", "
+             << Predicate.LeftOperand << ", " << Predicate.RightOperand << "},\n";
+    }
+    Output << "}};\n";
+    Output << "constexpr std::array<MacroFusionImmediateRelation, "
+           << Rule.ImmediateRelations.size() << "> " << Rule.Symbol << "ImmediateRelations = {{\n";
+    for (const NormalizedMacroFusionImmediateRelation &Relation : Rule.ImmediateRelations)
+      Output << "    {" << Relation.FirstOperand << ", " << Relation.SecondOperand << "},\n";
+    Output << "}};\n\n";
+  }
+
+  Output << "constexpr std::array<MacroFusionRule, " << Model.MacroFusionRules.size()
+         << "> GeneratedMacroFusionRules = {{\n";
+  for (const NormalizedMacroFusionRule &Rule : Model.MacroFusionRules) {
+    Output << "    {";
+    appendQuoted(Output, Rule.Symbol);
+    Output << ", ";
+    appendQuoted(Output, Rule.Feature);
+    Output << ", " << Rule.Symbol << "FirstOpcodes, " << Rule.Symbol << "SecondOpcodes, "
+           << Rule.Symbol << "OpcodePairs, " << Rule.Symbol << "ImmediatePredicates, "
+           << Rule.Symbol << "RegisterInequalities, " << Rule.Symbol << "ImmediateRelations, "
+           << Rule.FirstDefinitionOperand << ", " << Rule.SecondUseOperand << ", "
+           << Rule.SecondDefinitionOperand << ", ";
+    if (Rule.CommutableSecondUseOperand)
+      Output << *Rule.CommutableSecondUseOperand;
+    else
+      Output << "MacroFusionRule::NoOperand";
+    Output << ", " << (Rule.RequireSingleNonDebugUse ? "true" : "false") << ", "
+           << (Rule.RequireSecondDestinationTie ? "true" : "false") << "},\n";
+  }
+  Output << "}};\n\n";
+  Output << "[[nodiscard]] constexpr std::span<const MacroFusionRule> "
+            "generatedMacroFusionRules() noexcept {\n"
+            "  return GeneratedMacroFusionRules;\n"
+            "}\n\n";
+  Output << "#endif // GET_MACRO_FUSION_RULES\n";
+  return Output.str();
+}
+
+} // namespace rcc::targetgen