From 6907ed77452dcf409e0e3540cf7bd876e87b54b9 Mon Sep 17 00:00:00 2001
From: Kostis Sagonas <kostis@it.uu.se>
Date: Mon, 25 Feb 2013 16:56:58 +0100
Subject: Fix bug related to the handling of is_number/1 by the range analysis
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

The following module produced erroneous results when compiled with HiPE:

-module(a).
-export([foo/1]).

foo(X) when is_number(X) ->
    is_integer(X).

Running:

  1> c(a).
  2> a:foo(0).
  true
  3> hipe:c(a).
  4> a:foo(0).
  false      % *** WRONG ***

The problem was that the 'number' case for the `hipe_icode:type_test/1`
was going to the default case where the argument was determined as being
something other than an integer. Thanks to Sebastian Egner and Johannes
Weißl for bringing the bug into attention. Fixed on the day it was reported.
---
 lib/hipe/icode/hipe_icode_range.erl | 2 ++
 1 file changed, 2 insertions(+)

(limited to 'lib/hipe/icode/hipe_icode_range.erl')

diff --git a/lib/hipe/icode/hipe_icode_range.erl b/lib/hipe/icode/hipe_icode_range.erl
index c222e8a5d5..46c5a39f2c 100644
--- a/lib/hipe/icode/hipe_icode_range.erl
+++ b/lib/hipe/icode/hipe_icode_range.erl
@@ -784,6 +784,8 @@ analyse_type(Type, Info, Rewrite) ->
     integer ->
       TrueRange = inf(any_range(), OldVarRange),
       FalseRange = inf(none_range(), OldVarRange);
+    number ->
+      TrueRange = FalseRange = OldVarRange;
     _ ->
       TrueRange = inf(none_range(), OldVarRange),
       FalseRange = OldVarRange
-- 
cgit v1.2.3