While fixing up how rewrite_to_defined_overflow works, gcc.dg/Wrestrict-22.c
started
to fail. This is because `d p+ 2` would moved by LIM and then be rewritten not
using
pointer plus. The rewriting part is correct behavior. It only recently started
to be
moved out; due to r16-190-g6901d56fea2132.
Which has the following comment:
```
When we run before PRE and PRE is active hoist all expressions
since PRE would do so anyway and we can preserve range info
but PRE cannot.
```
This is not true if hoisting past the always executed point; so, instead of
hoisting
these statements all the way out of the max loops, take into account the always
executed
loop too.
Bootstrapped and tested on x86_64-linux-gnu.
gcc/ChangeLog:
* tree-ssa-loop-im.cc (compute_invariantness): Hoist to the always
executed point
if ignorning the cost.
Signed-off-by: Andrew Pinski <[email protected]>
---
gcc/tree-ssa-loop-im.cc | 22 +++++++++++++++++-----
1 file changed, 17 insertions(+), 5 deletions(-)
diff --git a/gcc/tree-ssa-loop-im.cc b/gcc/tree-ssa-loop-im.cc
index a3ca5af3e3e..b7f9f9befa5 100644
--- a/gcc/tree-ssa-loop-im.cc
+++ b/gcc/tree-ssa-loop-im.cc
@@ -1241,12 +1241,24 @@ compute_invariantness (basic_block bb)
lim_data->cost);
}
- if (lim_data->cost >= LIM_EXPENSIVE
- /* When we run before PRE and PRE is active hoist all expressions
- since PRE would do so anyway and we can preserve range info
- but PRE cannot. */
- || (flag_tree_pre && !in_loop_pipeline))
+ if (lim_data->cost >= LIM_EXPENSIVE)
set_profitable_level (stmt);
+ /* When we run before PRE and PRE is active hoist all expressions
+ to the always executed loop since PRE would do so anyway
+ and we can preserve range info while PRE cannot. */
+ else if (flag_tree_pre && !in_loop_pipeline
+ && outermost)
+ {
+ class loop *mloop = lim_data->max_loop;
+ if (loop_depth (outermost) > loop_depth (mloop))
+ {
+ mloop = outermost;
+ if (dump_file && (dump_flags & TDF_DETAILS))
+ fprintf (dump_file, " constraining to loop depth %d\n\n\n",
+ loop_depth (mloop));
+ }
+ set_level (stmt, bb->loop_father, mloop);
+ }
}
}
--
2.34.1
