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| author | Luc Van Oostenryck <luc.vanoostenryck@gmail.com> | 2018-07-22 01:23:24 +0200 |
|---|---|---|
| committer | Luc Van Oostenryck <luc.vanoostenryck@gmail.com> | 2018-07-25 16:36:51 +0200 |
| commit | e703906715b38a515c8d0a4815ee8e357ff1f6ba (patch) | |
| tree | d021c75fe8b9392dfe7d60420c13d47ca589e7a5 /FAQ | |
| parent | f20ca41c3e13c7c805b5f6d1cb56d9ca1fb29afd (diff) | |
| download | sparse-dev-e703906715b38a515c8d0a4815ee8e357ff1f6ba.tar.gz | |
shift: simplify LSR(LSR(x,N),N') & friends
A shift of a shift (of the same kind) is equivalent to a single
shitf with a count equal to the sum of the two initial counts.
In addition:
* for LSRs & SHLs, if the sum is >= to the instruction size, then
the result is zero.
* for ASRs, if the sum is >= to the instruction size, then
the result is the same as a shift of a count of size - 1.
Implement these simplifications if both shift counts are in range.
Signed-off-by: Luc Van Oostenryck <luc.vanoostenryck@gmail.com>
Diffstat (limited to 'FAQ')
0 files changed, 0 insertions, 0 deletions