test(furc/ssa): implement tests for SSA

furc/CMakeLists.txt

@@ -10,7 +10,6 @@ target_link_libraries(furc PRIVATE libfurc)
 
 include(GoogleTest)
 
-file(GLOB_RECURSE FURC_TESTS "test/**.cpp")
-add_executable(furc_tests ${FURC_TESTS})
+add_executable(furc_tests "test/ssa.cpp")
 target_link_libraries(furc_tests PRIVATE libfurc GTest::gtest_main)
-# gtest_discover_tests(furc_tests)
+gtest_discover_tests(furc_tests)

furc/test/ssa.cpp

@@ -0,0 +1,141 @@
+// NOLINTBEGIN(readability-identifier-naming)
+
+#include "gtest/gtest.h"
+#include <furc/middle/ir.hpp>
+#include <furc/middle/ssa.hpp>
+#include <unordered_set>
+#include <vector>
+
+namespace furc::test {
+
+class SsaCfg : public testing::Test {
+public:
+    SsaCfg()
+      : p_context(&p_function) {}
+protected:
+    void compute() { ssa::compute_cfg(p_function.blocks, p_cfgBlocks); }
+protected:
+    std::vector<ssa::cfg_block> p_cfgBlocks;
+
+    ir_function p_function;
+    ir_context  p_context;
+};
+
+TEST_F(SsaCfg, Diamond) {
+    ir_operand null = { ir_operand::Integer, static_cast<std::uint64_t>(0) };
+
+    // Entry
+    p_context.terminate(null, 1, 2);
+    p_context.new_next();
+    // A
+    p_context.terminate(3);
+    p_context.new_next();
+    // B
+    p_context.terminate(3);
+    p_context.new_next();
+    // C
+    p_context.terminate(4);
+    p_context.new_next();
+    // Exit
+    p_context.terminate();
+
+    compute();
+
+    EXPECT_EQ(p_cfgBlocks[0].sucs.size(), 2);
+    EXPECT_NE(p_cfgBlocks[0].sucs.find(1), p_cfgBlocks[0].sucs.end());
+    EXPECT_NE(p_cfgBlocks[0].sucs.find(2), p_cfgBlocks[0].sucs.end());
+    EXPECT_EQ(p_cfgBlocks[3].preds, p_cfgBlocks[0].sucs);
+    EXPECT_EQ(p_cfgBlocks[3].sucs.size(), 1);
+    EXPECT_NE(p_cfgBlocks[3].sucs.find(4), p_cfgBlocks[3].sucs.end());
+}
+
+class SsaDom : public testing::Test {
+public:
+    SsaDom()
+      : p_context(&p_function) {}
+protected:
+    void compute() {
+        ssa::compute_cfg(p_function.blocks, p_cfgBlocks);
+        p_ssaRegisters.resize(p_function.regCount);
+        ssa::collect_registers(p_function.blocks, p_ssaRegisters, p_ssaGlobals);
+
+        std::vector<std::uint64_t> order;
+        ssa::compute_rpo(p_cfgBlocks, p_ssaBlocks, order);
+
+        ssa::build_dtree(p_cfgBlocks, p_ssaBlocks, order);
+        ssa::compute_dfrontiers(p_cfgBlocks, p_ssaBlocks);
+
+        ssa::ssaification(p_function.blocks, p_cfgBlocks, p_ssaBlocks, p_ssaRegisters, p_ssaGlobals);
+        ssa::rename(p_function.blocks, p_function.regCount, p_cfgBlocks, p_ssaBlocks, order);
+    }
+protected:
+    std::vector<ssa::cfg_block>       p_cfgBlocks;
+    std::vector<ssa::ssa_block>       p_ssaBlocks;
+    std::vector<ssa::register_info>   p_ssaRegisters;
+    std::unordered_set<std::uint64_t> p_ssaGlobals;
+
+    ir_function p_function;
+    ir_context  p_context;
+};
+
+TEST_F(SsaDom, Diamond) {
+    ir_operand null = { ir_operand::Integer, static_cast<std::uint64_t>(0) };
+
+    // Entry
+    p_context.terminate(null, 1, 2);
+    p_context.new_next();
+    // A
+    p_context.add_instr(ir_instruction{ ir_instruction::Move,
+        ir_operand{ ir_operand::Register, static_cast<std::uint64_t>(0) },
+        { null } });
+    p_context.terminate(3);
+    p_context.new_next();
+    // B
+    p_context.add_instr(ir_instruction{ ir_instruction::Move,
+        ir_operand{ ir_operand::Register, static_cast<std::uint64_t>(0) },
+        { null } });
+    p_context.terminate(3);
+    p_context.new_next();
+    // C
+    p_context.add_instr(ir_instruction{ ir_instruction::Add,
+        ir_operand{ ir_operand::Register, static_cast<std::uint64_t>(0) },
+        { ir_operand{ ir_operand::Register, static_cast<std::uint64_t>(0) } } });
+    p_context.new_next();
+    // Exit
+    p_context.terminate();
+
+    p_function.regCount = 1;
+
+    compute();
+
+    EXPECT_TRUE(p_ssaBlocks[0].df.empty());
+
+    EXPECT_EQ(p_ssaBlocks[1].idom, 0);
+    EXPECT_EQ(p_ssaBlocks[1].df.size(), 1);
+    EXPECT_NE(p_ssaBlocks[1].df.find(3), p_ssaBlocks[1].df.end());
+
+    EXPECT_EQ(p_ssaBlocks[2].idom, 0);
+    EXPECT_EQ(p_ssaBlocks[2].df.size(), 1);
+    EXPECT_NE(p_ssaBlocks[2].df.find(3), p_ssaBlocks[2].df.end());
+
+    EXPECT_EQ(p_ssaBlocks[3].idom, 0);
+    EXPECT_TRUE(p_ssaBlocks[3].df.empty());
+
+    EXPECT_EQ(p_ssaBlocks[4].idom, 3);
+    EXPECT_TRUE(p_ssaBlocks[4].df.empty());
+
+    // Renaming
+    EXPECT_EQ(p_function.blocks[1].instructions.front(),
+        (ir_instruction{ ir_instruction::Move, ir_operand::reg(0, 3), { null } }));
+    EXPECT_EQ(p_function.blocks[2].instructions.front(),
+        (ir_instruction{ ir_instruction::Move, ir_operand::reg(0, 2), { null } }));
+    EXPECT_EQ(p_function.blocks[3].instructions.front(),
+        (ir_instruction{ ir_instruction::Phi,
+            ir_operand::reg(0, 0),
+            { ir_operand{ ir_operand::PhiPair, ir_operand::value_u::register_s{ 0, 2 }, 2 },
+                ir_operand{ ir_operand::PhiPair, ir_operand::value_u::register_s{ 0, 3 }, 1 } } }));
+}
+
+} // namespace furc::test
+
+// NOLINTEND(readability-identifier-naming)

furvm/CMakeLists.txt

@@ -13,4 +13,4 @@ include(GoogleTest)
 file(GLOB_RECURSE FURVM_TESTS "test/**.cpp")
 add_executable(furvm_tests ${FURVM_TESTS})
 target_link_libraries(furvm_tests PRIVATE libfurvm GTest::gtest_main)
-gtest_discover_tests(furvm_tests)
+gtest_discover_tests(furvm_tests)