From 74489a68095f5acbe3f8df3cee5c8832eb868a0b Mon Sep 17 00:00:00 2001
From: Francis Russell <francis@unchartedbackwaters.co.uk>
Date: Thu, 3 May 2012 17:31:51 +0100
Subject: [PATCH] Add min and max intrinsics to code generator.

---
 src/ofc/codegen/FortranGenerator.scala |  8 +++++++-
 src/ofc/codegen/Intrinsic.scala        | 24 ++++++++++++++++++++++++
 2 files changed, 31 insertions(+), 1 deletion(-)
 create mode 100644 src/ofc/codegen/Intrinsic.scala

diff --git a/src/ofc/codegen/FortranGenerator.scala b/src/ofc/codegen/FortranGenerator.scala
index 9f0ecd4..059e668 100644
--- a/src/ofc/codegen/FortranGenerator.scala
+++ b/src/ofc/codegen/FortranGenerator.scala
@@ -176,6 +176,7 @@ class FortranGenerator {
       case (c: NumericComparison[_]) => buildNumericComparison(c)
       case (c: NumericOperator[_]) => buildNumericOperator(c)
       case (c: Conversion[_,_]) => buildConversion(c)
+      case (i: Intrinsic[_]) => buildIntrinsic(i)
       case x => throw new UnimplementedException("Unknown expression type in FORTRAN generator: " + x.toString)
     }
   }
@@ -222,7 +223,12 @@ class FortranGenerator {
     case (_: ComplexType) => ExpHolder(maxPrec, "cmplx(%s)".format(buildExpression(c.getExpression)))
     case _ => throw new UnimplementedException("Fortran generator cannot handle conversion.")
   }
-    
+
+  private def buildIntrinsic(i: Intrinsic[_]) : ExpHolder = i match {
+    case (m: Min[_]) => ExpHolder(maxPrec, "min(%s, %s)".format(buildExpression(m.getLeft), buildExpression(m.getRight)))
+    case (m: Max[_]) => ExpHolder(maxPrec, "max(%s, %s)".format(buildExpression(m.getLeft), buildExpression(m.getRight)))
+    case _ => throw new UnimplementedException("Unknown intrinsic in Fortran generator: "+i)
+  } 
 
   private def buildNumericComparison(c: NumericComparison[_]) : ExpHolder =
     buildBinaryOperation(getBinaryOpInfo(c.getOperation), buildExpression(c.getLeft), buildExpression(c.getRight))
diff --git a/src/ofc/codegen/Intrinsic.scala b/src/ofc/codegen/Intrinsic.scala
new file mode 100644
index 0000000..a73c7ea
--- /dev/null
+++ b/src/ofc/codegen/Intrinsic.scala
@@ -0,0 +1,24 @@
+package ofc.codegen
+import ofc.LogicError
+
+abstract class Intrinsic[T <: Type] extends Expression[T]
+
+class Min[T <: Type](a: Expression[T], b: Expression[T])(implicit isNumeric: HasProperty[T, Numeric]) extends Intrinsic[T] {
+  if (a.getType != b.getType)
+    throw new LogicError("Parameters to min must have matching types.")
+
+  def getType = a.getType
+  def foreach[U](f: Expression[_] => U) = List(a, b).foreach(f)
+  def getLeft = a
+  def getRight = b
+}
+
+class Max[T <: Type](a: Expression[T], b: Expression[T])(implicit isNumeric: HasProperty[T, Numeric]) extends Intrinsic[T] {
+  if (a.getType != b.getType)
+    throw new LogicError("Parameters to max must have matching types.")
+
+  def getType = a.getType
+  def foreach[U](f: Expression[_] => U) = List(a, b).foreach(f)
+  def getLeft = a
+  def getRight = b
+}
-- 
2.47.3