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| author | Rask Ingemann Lambertsen <rask@sygehus.dk> | 2007-09-09 21:21:59 +0200 |
|---|---|---|
| committer | Rask Ingemann Lambertsen <rask@gcc.gnu.org> | 2007-09-09 19:21:59 +0000 |
| commit | 921c44189aae73ef85ea7ac4712e54f667fdd4f6 (patch) | |
| tree | 9cf93feb394109316dfdca4d1a5926ddbe2320f6 /gcc/doc/md.texi | |
| parent | 0098d8068657d4d1aa61585993a0a3e5ef6be2c8 (diff) | |
| download | gcc-921c44189aae73ef85ea7ac4712e54f667fdd4f6.zip gcc-921c44189aae73ef85ea7ac4712e54f667fdd4f6.tar.gz gcc-921c44189aae73ef85ea7ac4712e54f667fdd4f6.tar.bz2 | |
re PR target/30315 (optimize unsigned-add overflow test on x86 to use cpu flags from addl)
PR target/30315
* config/i386/i386.h (CANONICALIZE_COMPARISON): Delete.
* simplify-rtx.c (simplify_relational_operation_1): Add the
canonicalization from i386.h.
* doc/md.texi (Canonicalization of Instructions): Document it.
From-SVN: r128305
Diffstat (limited to 'gcc/doc/md.texi')
| -rw-r--r-- | gcc/doc/md.texi | 7 |
1 files changed, 6 insertions, 1 deletions
diff --git a/gcc/doc/md.texi b/gcc/doc/md.texi index 1b0d766..c75b983 100644 --- a/gcc/doc/md.texi +++ b/gcc/doc/md.texi @@ -1,5 +1,5 @@ @c Copyright (C) 1988, 1989, 1992, 1993, 1994, 1996, 1998, 1999, 2000, 2001, -@c 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc. +@c 2002, 2003, 2004, 2005, 2006, 2007 Free Software Foundation, Inc. @c This is part of the GCC manual. @c For copying conditions, see the file gcc.texi. @@ -5514,6 +5514,11 @@ An operand of @code{neg}, @code{not}, @code{mult}, @code{plus}, or above. @item +@code{(ltu (plus @var{a} @var{b}) @var{b})} is converted to +@code{(ltu (plus @var{a} @var{b}) @var{a})}. Likewise with @code{geu} instead +of @code{ltu}. + +@item @code{(minus @var{x} (const_int @var{n}))} is converted to @code{(plus @var{x} (const_int @var{-n}))}. |