Add rcp_instruction

4 files changed, 57 insertions, 0 deletions

diff --git a/evaluator.cpp b/evaluator.cpp
index c61b116..f554a0a 100644
--- a/evaluator.cpp
+++ b/evaluator.cpp
@@ -1,5 +1,6 @@
 #include <math.h>
 
+#include <stdio.h>
 #include "evaluator.h"
 
 #include "value.h"
@@ -167,3 +168,41 @@ sat_evaluator::evaluate(
 	}
 	return new float_value(val);
 }
+
+rcp_evaluator::rcp_evaluator() :
+	evaluator("RCP")
+	{ }
+
+value *
+rcp_evaluator::evaluate(
+	float_value * l,
+	float_value * r)
+{
+	float val;
+	int float_type;
+	fprintf(stderr, "RCP\n");
+	if (!l || !l->m_has_value) {
+		return default_evaluate(l, r);
+	}
+	/* XXX: This should be configurable via virtual functions. */
+	float_type = fpclassify(l->m_value);
+	switch(float_type) {
+	case FP_NAN:
+		val = NAN;
+		break;
+	case FP_INFINITE:
+		val = 0.0f;
+		break;
+	default:
+		/* XXX: fpclassify should be used to test for zero once I
+		 * figure out if FP_ZERO is portable. */
+		if (l->m_value == 0.0f) {
+			val = INFINITY;
+		} else {
+			val = 1.0f / l->m_value;
+		}
+		break;
+	}
+	fprintf(stderr, "val=%f\n", val);
+	return new float_value(val);
+}
diff --git a/evaluator.h b/evaluator.h
index cd90765..3786950 100644
--- a/evaluator.h
+++ b/evaluator.h
@@ -72,4 +72,13 @@ public:
 		float_value * l,
 		float_value * r);
 };
+
+class rcp_evaluator : public evaluator {
+public:
+	rcp_evaluator();
+	value * evaluate(
+		float_value * l,
+		float_value * r);
+};
+
 #endif //EVALUATOR_H_
diff --git a/instruction.cpp b/instruction.cpp
index 5787c21..0b703d0 100644
--- a/instruction.cpp
+++ b/instruction.cpp
@@ -127,3 +127,7 @@ sub_instruction::sub_instruction(std::vector<register_address> dst) :
 sat_instruction::sat_instruction(std::vector<register_address> dst) :
 	instruction("SAT", new sat_evaluator(), dst, 1)
 	{ }
+
+rcp_instruction::rcp_instruction(std::vector<register_address> dst) :
+	instruction("RCP", new rcp_evaluator(), dst, 1)
+	{ }
diff --git a/instruction.h b/instruction.h
index cded5ca..4e88aaa 100644
--- a/instruction.h
+++ b/instruction.h
@@ -78,4 +78,9 @@ public:
 	sat_instruction(std::vector<register_address> dst);
 };
 
+class rcp_instruction : public instruction {
+public:
+	rcp_instruction(std::vector<register_address> dst);
+};
+
 #endif //INSTRUCTION_H_