From 2459518bdd903203fce4bb408d0bf09be8b648c2 Mon Sep 17 00:00:00 2001
From: nickysn <nickysn@gmail.com>
Date: Sat, 18 Jan 2014 03:36:15 +0000
Subject: [PATCH] * use IMUL even for unsigned multiplication on x86_64, when
 overflow checking is   off

git-svn-id: trunk@26499 -
---
 compiler/x86_64/nx64add.pas | 4 +++-
 1 file changed, 3 insertions(+), 1 deletion(-)

diff --git a/compiler/x86_64/nx64add.pas b/compiler/x86_64/nx64add.pas
index b3317ac1f0..ecac934de9 100644
--- a/compiler/x86_64/nx64add.pas
+++ b/compiler/x86_64/nx64add.pas
@@ -49,8 +49,10 @@ interface
 
     procedure tx8664addnode.second_addordinal;
     begin
-      { filter unsigned MUL opcode, which requires special handling }
+      { filter unsigned MUL opcode, which requires special handling.
+        Note that when overflow checking is off, we can use IMUL instead. }
       if (nodetype=muln) and
+        (cs_check_overflow in current_settings.localswitches) and
         (not(is_signed(left.resultdef)) or
          not(is_signed(right.resultdef))) then
       begin