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| author | Zdenek Dvorak <ook@ucw.cz> | 2008-11-20 09:05:12 +0100 |
|---|---|---|
| committer | Zdenek Dvorak <rakdver@gcc.gnu.org> | 2008-11-20 08:05:12 +0000 |
| commit | dc5b3407f2997631c15eebccd8c9260e186f3e0a (patch) | |
| tree | 049852a66bb3c2b176b99851ac916058e794f7d0 /gcc/loop-iv.c | |
| parent | f9487002a446cc5f4c777a77afe7c6eaecfec4d0 (diff) | |
| download | gcc-dc5b3407f2997631c15eebccd8c9260e186f3e0a.zip gcc-dc5b3407f2997631c15eebccd8c9260e186f3e0a.tar.gz gcc-dc5b3407f2997631c15eebccd8c9260e186f3e0a.tar.bz2 | |
re PR rtl-optimization/32283 (Missed induction variable optimization)
PR rtl-optimization/32283
* tree-ssa-loop-niter.c (scev_probably_wraps_p): Use type of the base
of the induction variable to decide whether it may wrap.
* tree-ssa-loop-ivopts.c (rewrite_use_compare): Emit the initialization
of the bound before the loop.
* simplify-rtx.c (simplify_binary_operation_1): Add two simplifications
regarding AND.
(simplify_plus_minus): Only fail if no simplification is possible.
* loop-iv.c (simple_rhs_p): Consider reg + reg and reg << cst simple.
From-SVN: r142035
Diffstat (limited to 'gcc/loop-iv.c')
| -rw-r--r-- | gcc/loop-iv.c | 25 |
1 files changed, 19 insertions, 6 deletions
diff --git a/gcc/loop-iv.c b/gcc/loop-iv.c index 2523963..3723dbd 100644 --- a/gcc/loop-iv.c +++ b/gcc/loop-iv.c @@ -1337,13 +1337,26 @@ simple_rhs_p (rtx rhs) case MINUS: op0 = XEXP (rhs, 0); op1 = XEXP (rhs, 1); - /* Allow reg + const sets only. */ - if (REG_P (op0) && !HARD_REGISTER_P (op0) && CONSTANT_P (op1)) - return true; - if (REG_P (op1) && !HARD_REGISTER_P (op1) && CONSTANT_P (op0)) - return true; + /* Allow reg + const and reg + reg. */ + if (!(REG_P (op0) && !HARD_REGISTER_P (op0)) + && !CONSTANT_P (op0)) + return false; + if (!(REG_P (op1) && !HARD_REGISTER_P (op1)) + && !CONSTANT_P (op1)) + return false; - return false; + return true; + + case ASHIFT: + op0 = XEXP (rhs, 0); + op1 = XEXP (rhs, 1); + /* Allow reg << const. */ + if (!(REG_P (op0) && !HARD_REGISTER_P (op0))) + return false; + if (!CONSTANT_P (op1)) + return false; + + return true; default: return false; |