From dd82ffe70eba58e87926dcf4de3fe6de84e4bc26 Mon Sep 17 00:00:00 2001
From: Jeff Bezanson <jeff.bezanson@gmail.com>
Date: Wed, 7 Aug 2013 01:14:24 -0400
Subject: [PATCH] add custom inliner for isbits(). fixes #3938

---
 base/inference.jl  | 29 ++++++++++++++++++-----------
 base/reflection.jl |  2 +-
 2 files changed, 19 insertions(+), 12 deletions(-)

diff --git a/base/inference.jl b/base/inference.jl
index 7cb8d5f41e52d..bd0dc43be7c79 100644
--- a/base/inference.jl
+++ b/base/inference.jl
@@ -1667,20 +1667,27 @@ function inlineable(f, e::Expr, sv, enclosing_ast)
             return (e.args[3],())
         end
     end
-    # special-case inliners for known pure functions that compute types
-    if (is(f,apply_type) || is(f,fieldtype) ||
-        (isdefined(Main.Base,:typejoin) && is(f,Main.Base.typejoin)) ||
-        (isdefined(Main.Base,:promote_type) && is(f,Main.Base.promote_type))) &&
-        isType(e.typ) && isleaftype(e.typ.parameters[1])
-        return (e.typ.parameters[1],())
-    end
     if length(atypes)==2 && is(f,unbox) && isa(atypes[2],DataType)
+        # remove redundant unbox
         return (e.args[3],())
     end
-    if is(f,Union) && isType(e.typ)
-        union = e.typ.parameters[1]
-        if isa(union,UnionType) && all(isleaftype, (union::UnionType).types)
-            return (union,())
+    # special-case inliners for known pure functions that compute types
+    if isType(e.typ)
+        if (is(f,apply_type) || is(f,fieldtype) ||
+            (isdefined(Main.Base,:typejoin) && is(f,Main.Base.typejoin)) ||
+            (isdefined(Main.Base,:promote_type) && is(f,Main.Base.promote_type))) &&
+            isleaftype(e.typ.parameters[1])
+            return (e.typ.parameters[1],())
+        end
+        if isdefined(Main.Base,:isbits) && is(f,Main.Base.isbits) &&
+            isleaftype(e.typ.parameters[1])
+            return (isbits(e.typ.parameters[1]),())
+        end
+        if is(f,Union)
+            union = e.typ.parameters[1]
+            if isa(union,UnionType) && all(isleaftype, (union::UnionType).types)
+                return (union,())
+            end
         end
     end
     if isa(f,IntrinsicFunction)
diff --git a/base/reflection.jl b/base/reflection.jl
index 0cc777f586929..8e310aee75b55 100644
--- a/base/reflection.jl
+++ b/base/reflection.jl
@@ -33,7 +33,7 @@ object_id(x::ANY) = ccall(:jl_object_id, Uint, (Any,), x)
 const isimmutable = x->(isa(x,Tuple) || !typeof(x).mutable)
 isstructtype(t::DataType) = t.names!=() || (t.size==0 && !t.abstract)
 isstructtype(x) = false
-isbits(t::DataType) = !t.mutable && t.pointerfree
+isbits(t::DataType) = !t.mutable & t.pointerfree
 isbits(t::Type) = false
 isbits(x) = isbits(typeof(x))
 isleaftype(t::ANY) = ccall(:jl_is_leaf_type, Int32, (Any,), t) != 0