diff options
| author | Jim Wilson <wilson@cygnus.com> | 1999-08-02 23:53:14 +0000 |
|---|---|---|
| committer | Jim Wilson <wilson@gcc.gnu.org> | 1999-08-02 16:53:14 -0700 |
| commit | fae2db4744dd199c7aea8cf48b3ab7a1282e98cc (patch) | |
| tree | 9bf61dfd34ec2e53b7a7fbb4d336c46731585eeb /gcc | |
| parent | a47f48d8fc2ca345f52c851f0ce711d76fcc7a89 (diff) | |
| download | gcc-fae2db4744dd199c7aea8cf48b3ab7a1282e98cc.zip gcc-fae2db4744dd199c7aea8cf48b3ab7a1282e98cc.tar.gz gcc-fae2db4744dd199c7aea8cf48b3ab7a1282e98cc.tar.bz2 | |
Optimize duplicate zero_extend operations.
* combine.c (force_to_mode, case LSHIFTRT): Add goto shiftrt.
(force_to_mode, case ASHIFTRT): Add shiftrt label.
From-SVN: r28424
Diffstat (limited to 'gcc')
| -rw-r--r-- | gcc/ChangeLog | 5 | ||||
| -rw-r--r-- | gcc/combine.c | 7 |
2 files changed, 10 insertions, 2 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index fe7eec1..9592319 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,3 +1,8 @@ +Mon Aug 2 16:27:42 1999 Jim Wilson <wilson@cygnus.com> + + * combine.c (force_to_mode, case LSHIFTRT): Add goto shiftrt. + (force_to_mode, case ASHIFTRT): Add shiftrt label. + Tue Aug 3 00:45:02 1999 J"orn Rennecke <amylaar@cygnus.co.uk> * loop.c (strength_reduce): When doing biv->giv conversion, update diff --git a/gcc/combine.c b/gcc/combine.c index c9736e5..c922c86 100644 --- a/gcc/combine.c +++ b/gcc/combine.c @@ -6574,7 +6574,8 @@ force_to_mode (x, mode, mask, reg, just_select) x = gen_binary (LSHIFTRT, GET_MODE (x), XEXP (x, 0), GEN_INT (GET_MODE_BITSIZE (GET_MODE (x)) - exact_log2 (mask + 1))); - break; + + goto shiftrt; case ASHIFTRT: /* If we are just looking for the sign bit, we don't need this shift at @@ -6639,7 +6640,9 @@ force_to_mode (x, mode, mask, reg, just_select) if (mask == 1) x = gen_binary (LSHIFTRT, GET_MODE (x), XEXP (x, 0), XEXP (x, 1)); - /* If this is a sign-extension operation that just affects bits + shiftrt: + + /* If this is a zero- or sign-extension operation that just affects bits we don't care about, remove it. Be sure the call above returned something that is still a shift. */ |