diff options
| author | Siddhesh Poyarekar <siddhesh@gotplt.org> | 2021-10-19 09:36:35 +0530 |
|---|---|---|
| committer | Siddhesh Poyarekar <siddhesh@gotplt.org> | 2021-10-20 08:28:20 +0530 |
| commit | 9fbb6fa123be81c55e888e5d117e63d05780f0ed (patch) | |
| tree | 21192de96a3f53dd030f8955723ab079c615fd8c /gcc/tree-ssa-threadupdate.c | |
| parent | 3c8d8c0be95e99dc0cba7f6fad2429243582119f (diff) | |
| download | gcc-9fbb6fa123be81c55e888e5d117e63d05780f0ed.zip gcc-9fbb6fa123be81c55e888e5d117e63d05780f0ed.tar.gz gcc-9fbb6fa123be81c55e888e5d117e63d05780f0ed.tar.bz2 | |
tree-object-size: Make unknown a computation
Compute the unknown size value as a function of the min/max bit of
object_size_type. This transforms into a neat little branchless
sequence on x86_64:
movl %edi, %eax
sarl %eax
xorl $1, %eax
negl %eax
cltq
which should be faster than loading the value from memory. A quick
unscientific test using
`time make check-gcc RUNTESTFLAGS="dg.exp=builtin*"`
shaves about half a second off execution time with this. Also simplify
implementation of unknown_object_size.
gcc/ChangeLog:
* tree-object-size.c (unknown): Make into a function. Adjust
all uses.
(unknown_object_size): Simplify implementation.
Signed-off-by: Siddhesh Poyarekar <siddhesh@gotplt.org>
Diffstat (limited to 'gcc/tree-ssa-threadupdate.c')
0 files changed, 0 insertions, 0 deletions