Add sat_instruction

4 files changed, 40 insertions, 0 deletions

diff --git a/evaluator.cpp b/evaluator.cpp
index 2741d84..c61b116 100644
--- a/evaluator.cpp
+++ b/evaluator.cpp
@@ -144,3 +144,26 @@ sub_evaluator::evaluate(
 	}
 	return new float_value(l->m_value - r->m_value);
 }
+
+sat_evaluator::sat_evaluator() :
+	evaluator("SAT")
+	{ }
+
+value *
+sat_evaluator::evaluate(
+	float_value * l,
+	float_value * r)
+{
+	float val;
+	if (!l || !l->m_has_value) {
+		return default_evaluate(l, r);
+	}
+	val = l->m_value;
+	if (val < 0.0f) {
+		val = 0.0f;
+	}
+	if (val > 1.0f) {
+		val = 1.0f;
+	}
+	return new float_value(val);
+}
diff --git a/evaluator.h b/evaluator.h
index 2b3f682..cd90765 100644
--- a/evaluator.h
+++ b/evaluator.h
@@ -64,4 +64,12 @@ public:
 		float_value * l,
 		float_value * r);
 };
+
+class sat_evaluator : public evaluator {
+public:
+	sat_evaluator();
+	value * evaluate(
+		float_value * l,
+		float_value * r);
+};
 #endif //EVALUATOR_H_
diff --git a/instruction.cpp b/instruction.cpp
index 52dc8ba..5787c21 100644
--- a/instruction.cpp
+++ b/instruction.cpp
@@ -123,3 +123,7 @@ abs_instruction::abs_instruction(std::vector<register_address> dst) :
 sub_instruction::sub_instruction(std::vector<register_address> dst) :
 	instruction("SUB", new sub_evaluator(), dst, 2)
 	{ }
+
+sat_instruction::sat_instruction(std::vector<register_address> dst) :
+	instruction("SAT", new sat_evaluator(), dst, 1)
+	{ }
diff --git a/instruction.h b/instruction.h
index 13bf4de..cded5ca 100644
--- a/instruction.h
+++ b/instruction.h
@@ -73,4 +73,9 @@ public:
 	sub_instruction(std::vector<register_address> dst);
 };
 
+class sat_instruction : public instruction {
+public:
+	sat_instruction(std::vector<register_address> dst);
+};
+
 #endif //INSTRUCTION_H_