LLVMCodeBuilder: Implement lower than comparison

Author: adazem009

src/dev/engine/internal/icodebuilder.h

@@ -31,6 +31,8 @@ class ICodeBuilder
 
         virtual void createCmpEQ() = 0;
         virtual void createCmpGT() = 0;
+        virtual void createCmpLT() = 0;
+
         virtual void beginIfStatement() = 0;
         virtual void beginElseBranch() = 0;
         virtual void endIf() = 0;

src/dev/engine/internal/llvmcodebuilder.cpp

@@ -144,6 +144,14 @@ std::shared_ptr<ExecutableCode> LLVMCodeBuilder::finalize()
                 break;
             }
 
+            case Step::Type::CmpLT: {
+                assert(step.args.size() == 2);
+                const auto &arg1 = step.args[0].second;
+                const auto &arg2 = step.args[1].second;
+                step.functionReturnReg->value = createComparison(arg1, arg2, Comparison::LT);
+                break;
+            }
+
             case Step::Type::Yield:
                 if (!m_warp) {
                     freeHeap();
@@ -492,6 +500,11 @@ void LLVMCodeBuilder::createCmpGT()
     createOp(Step::Type::CmpGT, Compiler::StaticType::Bool, 2);
 }
 
+void LLVMCodeBuilder::createCmpLT()
+{
+    createOp(Step::Type::CmpLT, Compiler::StaticType::Bool, 2);
+}
+
 void LLVMCodeBuilder::beginIfStatement()
 {
     Step step(Step::Type::BeginIf);
@@ -1036,8 +1049,25 @@ llvm::Value *LLVMCodeBuilder::createComparison(std::shared_ptr<Register> arg1, s
                             return m_builder.CreateAnd(m_builder.CreateNot(bothNan), m_builder.CreateSelect(nan, nanCmp, cmp));
                         }
 
-                        case Comparison::LT:
-                            return m_builder.CreateFCmpOLT(value1, value2);
+                        case Comparison::LT: {
+                            llvm::Value *bothNan = m_builder.CreateAnd(isNaN(value1), isNaN(value2)); // NaN == NaN
+                            llvm::Value *cmp = m_builder.CreateFCmpOLT(value1, value2);
+                            llvm::Value *nan;
+                            llvm::Value *nanCmp;
+
+                            if (optNumberBool == 1) {
+                                nan = isNaN(value2);
+                                nanCmp = m_builder.CreateNot(castValue(arg1, Compiler::StaticType::Bool));
+                            } else if (optNumberBool == 2) {
+                                nan = isNaN(value1);
+                                nanCmp = castValue(arg2, Compiler::StaticType::Bool);
+                            } else {
+                                nan = isNaN(value2);
+                                nanCmp = m_builder.CreateFCmpULT(value1, value2);
+                            }
+
+                            return m_builder.CreateAnd(m_builder.CreateNot(bothNan), m_builder.CreateSelect(nan, nanCmp, cmp));
+                        }
 
                         default:
                             assert(false);
@@ -1056,7 +1086,8 @@ llvm::Value *LLVMCodeBuilder::createComparison(std::shared_ptr<Register> arg1, s
                             return m_builder.CreateAnd(value1, m_builder.CreateNot(value2));
 
                         case Comparison::LT:
-                            return m_builder.CreateICmpSLT(value1, value2);
+                            // value2 && !value1
+                            return m_builder.CreateAnd(value2, m_builder.CreateNot(value1));
 
                         default:
                             assert(false);

src/dev/engine/internal/llvmcodebuilder.h

@@ -33,6 +33,8 @@ class LLVMCodeBuilder : public ICodeBuilder
 
         void createCmpEQ() override;
         void createCmpGT() override;
+        void createCmpLT() override;
+
         void beginIfStatement() override;
         void beginElseBranch() override;
         void endIf() override;
@@ -71,6 +73,7 @@ class LLVMCodeBuilder : public ICodeBuilder
                     Div,
                     CmpEQ,
                     CmpGT,
+                    CmpLT,
                     Yield,
                     BeginIf,
                     BeginElse,

test/dev/llvm/llvmcodebuilder_test.cpp

@@ -595,9 +595,10 @@ TEST_F(LLVMCodeBuilderTest, EqualComparison)
     addOpTest(nan, "0");
 }
 
-TEST_F(LLVMCodeBuilderTest, GreaterThanComparison)
+TEST_F(LLVMCodeBuilderTest, GreaterAndLowerThanComparison)
 {
     auto addOpTest = [this](Value v1, Value v2) {
+        // GT
         createBuilder(true);
 
         m_builder->addConstValue(v1);
@@ -622,7 +623,32 @@ TEST_F(LLVMCodeBuilderTest, GreaterThanComparison)
         code->run(ctx.get());
         const std::string quotes1 = v1.isString() ? "\"" : "";
         const std::string quotes2 = v2.isString() ? "\"" : "";
-        ASSERT_THAT(testing::internal::GetCapturedStdout(), Eq(expected)) << quotes1 << v1.toString() << quotes1 << " " << quotes2 << v2.toString() << quotes2;
+        ASSERT_THAT(testing::internal::GetCapturedStdout(), Eq(expected)) << "GT: " << quotes1 << v1.toString() << quotes1 << " " << quotes2 << v2.toString() << quotes2;
+
+        // LT
+        createBuilder(true);
+
+        m_builder->addConstValue(v1);
+        m_builder->addConstValue(v2);
+        m_builder->createCmpLT();
+        m_builder->addFunctionCall("test_print_string", Compiler::StaticType::Void, { Compiler::StaticType::String });
+
+        m_builder->addConstValue(v1);
+        callConstFuncForType(v1.type());
+        m_builder->addConstValue(v2);
+        callConstFuncForType(v2.type());
+        m_builder->createCmpLT();
+        m_builder->addFunctionCall("test_print_string", Compiler::StaticType::Void, { Compiler::StaticType::String });
+
+        str = Value(v1 < v2).toString() + '\n';
+        expected = str + str;
+
+        code = m_builder->finalize();
+        ctx = code->createExecutionContext(&m_target);
+
+        testing::internal::CaptureStdout();
+        code->run(ctx.get());
+        ASSERT_THAT(testing::internal::GetCapturedStdout(), Eq(expected)) << "LT: " << quotes1 << v1.toString() << quotes1 << " " << quotes2 << v2.toString() << quotes2;
     };
 
     addOpTest(10, 10);

test/mocks/codebuildermock.h

@@ -21,6 +21,8 @@ class CodeBuilderMock : public ICodeBuilder
 
         MOCK_METHOD(void, createCmpEQ, (), (override));
         MOCK_METHOD(void, createCmpGT, (), (override));
+        MOCK_METHOD(void, createCmpLT, (), (override));
+
         MOCK_METHOD(void, beginIfStatement, (), (override));
         MOCK_METHOD(void, beginElseBranch, (), (override));
         MOCK_METHOD(void, endIf, (), (override));