[freetype2] master 3ea0d2c: * src/base/ftcalc.c (FT_MulFix) [FT_LONG64]: Improve.

[Alexei Podtelezhnikov]

branch: master
commit 3ea0d2c65a931e721aaf732c17765968bfe755d2
Author: Alexei Podtelezhnikov <address@hidden>
Commit: Alexei Podtelezhnikov <address@hidden>

    * src/base/ftcalc.c (FT_MulFix) [FT_LONG64]: Improve.
---
 ChangeLog         |    4 ++++
 src/base/ftcalc.c |   18 +++---------------
 2 files changed, 7 insertions(+), 15 deletions(-)

diff --git a/ChangeLog b/ChangeLog
index be16ae0..cd4fe58 100644
--- a/ChangeLog
+++ b/ChangeLog
@@ -1,3 +1,7 @@
+2015-09-14  Alexei Podtelezhnikov  <address@hidden>
+
+       * src/base/ftcalc.c (FT_MulFix) [FT_LONG64]: Improve.
+
 2015-09-14  Werner Lemberg  <address@hidden>
 
        [type1] Fix another potential buffer overflow (#45955).
diff --git a/src/base/ftcalc.c b/src/base/ftcalc.c
index dbddeda..619a08b 100644
--- a/src/base/ftcalc.c
+++ b/src/base/ftcalc.c
@@ -237,22 +237,10 @@
 
 #else
 
-    FT_Int     s = 1;
-    FT_UInt64  a, b, c;
-    FT_Long    c_;
-
-
-    FT_MOVE_SIGN( a_, s );
-    FT_MOVE_SIGN( b_, s );
-
-    a = (FT_UInt64)a_;
-    b = (FT_UInt64)b_;
-
-    c = ( a * b + 0x8000UL ) >> 16;
-
-    c_ = (FT_Long)c;
+    FT_Int64  ab = (FT_Int64)a_ * (FT_Int64)b_;
 
-    return s < 0 ? -c_ : c_;
+    /* this requires arithmetic right shift of signed numbers */
+    return (FT_Long)( ( ab + 0x8000L - ( ab < 0 ) ) >> 16 );
 
 #endif /* FT_MULFIX_ASSEMBLER */
   }