4 files changed, 10 insertions, 0 deletions
diff --git a/ABC/Machine/BStack.dcl b/ABC/Machine/BStack.dcl
index 900e856..9d938ef 100644
--- a/ABC/Machine/BStack.dcl
+++ b/ABC/Machine/BStack.dcl
@@ -36,5 +36,6 @@ bs_eqIi   :: Int BSrc BStack -> BStack
 bs_gtI    :: BStack -> BStack
 bs_ltI    :: BStack -> BStack
 bs_mulI   :: BStack -> BStack
+bs_negI   :: BStack -> BStack
 bs_remI   :: BStack -> BStack
 bs_subI   :: BStack -> BStack
diff --git a/ABC/Machine/BStack.icl b/ABC/Machine/BStack.icl
index 70007fd..a9a2d0e 100644
--- a/ABC/Machine/BStack.icl
+++ b/ABC/Machine/BStack.icl
@@ -102,6 +102,10 @@ bs_mulI   :: BStack -> BStack
 bs_mulI [Int m:Int n:s] = bs_pushI (m * n) s
 bs_mulI _               = abortn "bs_mulI: no integers"
 
+bs_negI   :: BStack -> BStack
+bs_negI [Int n:s] = bs_pushI (~n) s
+bs_negI _         = abortn "bs_negI: no integer"
+
 bs_remI   :: BStack -> BStack
 bs_remI [Int m:Int n:s] = bs_pushI (m rem n) s
 bs_remI _               = abortn "bs_remI: no integers"
diff --git a/ABC/Machine/Instructions.dcl b/ABC/Machine/Instructions.dcl
index 5140c98..d5a37f9 100644
--- a/ABC/Machine/Instructions.dcl
+++ b/ABC/Machine/Instructions.dcl
@@ -62,5 +62,6 @@ gtI  :: State -> State
 incI :: State -> State
 ltI  :: State -> State
 mulI :: State -> State
+negI :: State -> State
 remI :: State -> State
 subI :: State -> State
diff --git a/ABC/Machine/Instructions.icl b/ABC/Machine/Instructions.icl
index 42dcb62..54e7ebd 100644
--- a/ABC/Machine/Instructions.icl
+++ b/ABC/Machine/Instructions.icl
@@ -385,6 +385,10 @@ mulI :: State -> State
 mulI st=:{bstack}
 	= {st & bstack=bs_mulI bstack}
 
+negI :: State -> State
+negI st=:{bstack}
+	= {st & bstack=bs_negI bstack}
+
 remI :: State -> State
 remI st=:{bstack}
 	= {st & bstack=bs_remI bstack}