[TableGen] Split the target description generator

1 files changed, 202 insertions, 0 deletions

diff --git a/backend/unittests/Target/TableGenTest.cpp b/backend/unittests/Target/TableGenTest.cpp
new file mode 100644
index 0000000..af4d718
--- /dev/null
+++ b/backend/unittests/Target/TableGenTest.cpp
@@ -0,0 +1,202 @@
+// SPDX-License-Identifier: GPL-3.0-or-later
+
+#include "TableGenBackends.h"
+
+#include <cstddef>
+#include <iostream>
+#include <string>
+#include <string_view>
+
+namespace {
+
+class TestContext final {
+public:
+  void expect(bool Condition, std::string_view Message) {
+    if (Condition)
+      return;
+    std::cerr << Message << '\n';
+    ++FailureCount;
+  }
+
+  [[nodiscard]] int result() const noexcept {
+    return FailureCount == 0 ? 0 : 1;
+  }
+
+private:
+  int FailureCount = 0;
+};
+
+[[nodiscard]] std::string validDescription(std::string_view Aliases = "[acc]") {
+  return std::string(R"(schema: rcc-target-description-v2
+target:
+  namespace: tiny
+  name: Tiny
+  triple: tiny-unknown-none
+  cpu: tiny-cpu
+  abi: tiny-abi
+  data_layout: e-p:64:64
+  features: [base]
+register_units:
+  - { id: 1, symbol: U_R1, name: r1.unit }
+registers:
+  - { id: 1, symbol: R1, name: r1, encoding: 0, dwarf_register: 0, units: [{ unit: U_R1, lanes: 1 }], aliases: )") +
+         std::string(Aliases) + R"( }
+register_banks:
+  - { id: 1, symbol: GPR, name: GPR, maximum_size_bits: 64 }
+register_classes:
+  - { id: 1, symbol: GPR64, name: GPR64, bank: GPR, size_bits: 64, spill_size_bits: 64, spill_alignment_bits: 64, lanes: 1, registers: [R1], allocation_order: [R1] }
+register_masks:
+  - { name: CSR_TINY, preserved: [R1] }
+mir_operand_flags:
+  direct_mask: 31
+  direct: [{ name: tiny-call, value: 1 }]
+  bitmask: [{ name: tiny-relax, value: 32 }]
+calling_conventions:
+  - { id: 1, symbol: TINY, name: tiny, integer_register_class: GPR64, floating_register_class: GPR64, integer_argument_registers: [R1], floating_argument_registers: [R1], integer_return_registers: [R1], floating_return_registers: [R1], preserved_mask: CSR_TINY, stack_alignment_bytes: 8, stack_argument_alignment_bytes: 8, shadow_space_bytes: 0, supports_varargs: true, supports_tail_calls: true }
+named_operands:
+  - { id: 1, symbol: RD, name: rd }
+  - { id: 2, symbol: IMM, name: imm }
+immediate_predicates:
+  - { id: 1, symbol: SIMM8, name: simm8, kind: signed, bits: 8 }
+scheduling_classes:
+  - { id: 1, symbol: ALU, name: alu, micro_ops: 1, latency: 1 }
+encoding_categories:
+  - { id: 1, symbol: I, name: i, size_bytes: 4 }
+assembly_formats:
+  - { id: 1, symbol: RD_IMM, name: rd-imm }
+instructions:
+  - { id: 1024, symbol: LOAD_IMM, name: LOAD_IMM, assembly_mnemonic: load.imm, encoding: 19, operands: [{ kinds: [register], role: def, register_class: GPR64, register_bank: GPR, name: RD }, { kinds: [immediate, global_symbol], immediate_predicate: SIMM8, name: IMM, allowed_target_flags: 33 }], num_explicit_defs: 1, flags: [produces_code], scheduling_class: ALU, encoding_category: I, assembly_format: RD_IMM }
+)";
+}
+
+void testGeneration(TestContext &Context) {
+  const auto First = rcc::targetgen::generateDescription("tiny.rccdesc", validDescription());
+  const auto Second = rcc::targetgen::generateDescription("tiny.rccdesc", validDescription());
+  if (!First.succeeded()) {
+    for (const rcc::TextDiagnostic &Diagnostic : First.Diagnostics)
+      std::cerr << Diagnostic.Message << '\n';
+  }
+  Context.expect(First.succeeded() && Second.succeeded(),
+                 "a complete restricted target description must generate successfully");
+  if (!First.succeeded() || !Second.succeeded() || !First.Output || !Second.Output)
+    return;
+  const auto &FirstOutput = First.Output.value();
+  const auto &SecondOutput = Second.Output.value();
+
+  Context.expect(FirstOutput.RegisterHeader == SecondOutput.RegisterHeader &&
+                     FirstOutput.InstructionHeader == SecondOutput.InstructionHeader &&
+                     FirstOutput.TargetTables == SecondOutput.TargetTables,
+                 "target description generation must be deterministic");
+  Context.expect(
+      FirstOutput.RegisterHeader.find("enum class PhysicalRegisterID") != std::string::npos &&
+          FirstOutput.RegisterHeader.find("R1 = 1") != std::string::npos &&
+          FirstOutput.InstructionHeader.find("enum class InstructionOpcode") != std::string::npos &&
+          FirstOutput.InstructionHeader.find("LOAD_IMM = 1024") != std::string::npos &&
+          FirstOutput.TargetTables.find("appendGeneratedRegisterInfo") != std::string::npos &&
+          FirstOutput.TargetTables.find("appendGeneratedInstructionInfo") != std::string::npos &&
+          FirstOutput.TargetTables.find("GeneratedAssemblyInstructions") != std::string::npos &&
+          FirstOutput.TargetTables.find("Description.DirectOperandFlagMask = 31") !=
+              std::string::npos &&
+          FirstOutput.TargetTables.find("\"tiny-call\", 1") != std::string::npos &&
+          FirstOutput.TargetTables.find("\"load.imm\"") != std::string::npos &&
+          FirstOutput.TargetTables.find("makePreservedMask") != std::string::npos,
+      "generated output must contain typed target IDs, assembly mnemonics, and static target "
+      "tables");
+}
+
+void testSemanticRejection(TestContext &Context) {
+  const auto CollidingAlias =
+      rcc::targetgen::generateDescription("bad-alias.rccdesc", validDescription("[r1]"));
+  if (CollidingAlias.succeeded())
+    std::cerr << "colliding alias description unexpectedly generated\n";
+  Context.expect(!CollidingAlias.succeeded() && !CollidingAlias.Diagnostics.empty() &&
+                     CollidingAlias.Diagnostics.front().Message.find("aliases") !=
+                         std::string::npos,
+                 "an ABI alias that collides with a canonical name must be rejected");
+
+  std::string UnknownUnit = validDescription();
+  constexpr std::string_view UnitReference = "unit: U_R1";
+  const std::size_t UnitPosition = UnknownUnit.find(UnitReference);
+  if (UnitPosition != std::string::npos)
+    UnknownUnit.replace(UnitPosition, UnitReference.size(), "unit: U_MISSING");
+  const auto BadUnit = rcc::targetgen::generateDescription("bad-unit.rccdesc", UnknownUnit);
+  Context.expect(!BadUnit.succeeded() && !BadUnit.Diagnostics.empty() &&
+                     BadUnit.Diagnostics.front().Message.find("declared units") !=
+                         std::string::npos,
+                 "a register unit reference must resolve during semantic validation");
+
+  std::string UnknownClass = validDescription();
+  constexpr std::string_view ClassReference = "register_class: GPR64";
+  const std::size_t ClassPosition = UnknownClass.find(ClassReference);
+  if (ClassPosition != std::string::npos)
+    UnknownClass.replace(ClassPosition, ClassReference.size(), "register_class: MISSING");
+  const auto BadClass =
+      rcc::targetgen::generateDescription("bad-instruction-class.rccdesc", UnknownClass);
+  Context.expect(!BadClass.succeeded() && !BadClass.Diagnostics.empty() &&
+                     BadClass.Diagnostics.front().Message.find("register class") !=
+                         std::string::npos,
+                 "instruction register classes must resolve during semantic validation");
+
+  std::string BadAllowedValue = validDescription();
+  constexpr std::string_view Predicate = "kind: signed, bits: 8";
+  const std::size_t PredicatePosition = BadAllowedValue.find(Predicate);
+  if (PredicatePosition != std::string::npos) {
+    BadAllowedValue.replace(PredicatePosition, Predicate.size(),
+                            "kind: signed, bits: 8, allowed_values: [128]");
+  }
+  const auto InvalidAllowedValue =
+      rcc::targetgen::generateDescription("bad-allowed-value.rccdesc", BadAllowedValue);
+  Context.expect(!InvalidAllowedValue.succeeded() && !InvalidAllowedValue.Diagnostics.empty() &&
+                     InvalidAllowedValue.Diagnostics.front().Message.find("allowed_values") !=
+                         std::string::npos,
+                 "immediate predicates must reject allowed values outside their signed range");
+
+  std::string ContradictoryNonZero = validDescription();
+  if (PredicatePosition != std::string::npos) {
+    const std::size_t Position = ContradictoryNonZero.find(Predicate);
+    ContradictoryNonZero.replace(Position, Predicate.size(),
+                                 "kind: signed, bits: 8, nonzero: true, allowed_values: [0]");
+  }
+  const auto InvalidNonZero =
+      rcc::targetgen::generateDescription("bad-nonzero.rccdesc", ContradictoryNonZero);
+  Context.expect(!InvalidNonZero.succeeded() && !InvalidNonZero.Diagnostics.empty() &&
+                     InvalidNonZero.Diagnostics.front().Message.find("allowed_values") !=
+                         std::string::npos,
+                 "nonzero immediate predicates must reject an explicit zero value");
+
+  std::string BadStackAlignment = validDescription();
+  constexpr std::string_view StackAlignment =
+      "stack_alignment_bytes: 8, stack_argument_alignment_bytes: 8";
+  const std::size_t StackPosition = BadStackAlignment.find(StackAlignment);
+  if (StackPosition != std::string::npos) {
+    BadStackAlignment.replace(StackPosition, StackAlignment.size(),
+                              "stack_alignment_bytes: 8, stack_argument_alignment_bytes: 16");
+  }
+  const auto InvalidStackAlignment =
+      rcc::targetgen::generateDescription("bad-stack-alignment.rccdesc", BadStackAlignment);
+  Context.expect(!InvalidStackAlignment.succeeded() && !InvalidStackAlignment.Diagnostics.empty() &&
+                     InvalidStackAlignment.Diagnostics.front().Message.find("stack alignments") !=
+                         std::string::npos,
+                 "calling conventions must reject incompatible stack alignments");
+
+  std::string BadMnemonic = validDescription();
+  constexpr std::string_view Mnemonic = "assembly_mnemonic: load.imm";
+  const std::size_t MnemonicPosition = BadMnemonic.find(Mnemonic);
+  if (MnemonicPosition != std::string::npos)
+    BadMnemonic.replace(MnemonicPosition, Mnemonic.size(), "assembly_mnemonic: .load");
+  const auto InvalidMnemonic =
+      rcc::targetgen::generateDescription("bad-mnemonic.rccdesc", BadMnemonic);
+  Context.expect(!InvalidMnemonic.succeeded() && !InvalidMnemonic.Diagnostics.empty() &&
+                     InvalidMnemonic.Diagnostics.front().Message.find("assembly mnemonics") !=
+                         std::string::npos,
+                 "assembly mnemonics must use a canonical lowercase spelling");
+}
+
+} // namespace
+
+int main() {
+  TestContext Context;
+  testGeneration(Context);
+  testSemanticRejection(Context);
+  return Context.result();
+}