From f3bd82bdae3ebce5289b1a1bed9105c5bf04fdbe Mon Sep 17 00:00:00 2001 From: Cliff Click Date: Sun, 29 Oct 2023 10:45:20 -0700 Subject: Fix div-by-0, some javadoc higher level parsers can return null, but their return is ignored anycase. div-by-0 is defined to be 0, backported to ch2,3,4,5 --- chapter04/src/main/java/com/seaofnodes/simple/node/DivNode.java | 9 ++++----- .../src/main/java/com/seaofnodes/simple/type/TypeInteger.java | 1 + 2 files changed, 5 insertions(+), 5 deletions(-) (limited to 'chapter04/src') diff --git a/chapter04/src/main/java/com/seaofnodes/simple/node/DivNode.java b/chapter04/src/main/java/com/seaofnodes/simple/node/DivNode.java index 22167a87..1f562378 100644 --- a/chapter04/src/main/java/com/seaofnodes/simple/node/DivNode.java +++ b/chapter04/src/main/java/com/seaofnodes/simple/node/DivNode.java @@ -23,11 +23,10 @@ public class DivNode extends Node { public Type compute() { if (in(1)._type instanceof TypeInteger i0 && in(2)._type instanceof TypeInteger i1) { - if (i0.isConstant() && i1.isConstant()) { - if (i1.value() == 0) - throw new IllegalArgumentException("Divide by zero"); - return TypeInteger.constant(i0.value()/i1.value()); - } + if (i0.isConstant() && i1.isConstant()) + return i1.value() == 0 + ? TypeInteger.ZERO + : TypeInteger.constant(i0.value()/i1.value()); return i0.meet(i1); } return TypeBot.BOTTOM; diff --git a/chapter04/src/main/java/com/seaofnodes/simple/type/TypeInteger.java b/chapter04/src/main/java/com/seaofnodes/simple/type/TypeInteger.java index e23840e0..b53b1b29 100644 --- a/chapter04/src/main/java/com/seaofnodes/simple/type/TypeInteger.java +++ b/chapter04/src/main/java/com/seaofnodes/simple/type/TypeInteger.java @@ -7,6 +7,7 @@ public class TypeInteger extends Type { public final static TypeInteger TOP = new TypeInteger(false, 0); public final static TypeInteger BOT = new TypeInteger(false, 1); + public final static TypeInteger ZERO= new TypeInteger(true, 0); private final boolean _is_con; -- cgit v1.2.3