On Thu, 2016-06-30 at 10:50 +0300, Dan Carpenter wrote:
> On Wed, Jun 29, 2016 at 10:05:53AM -0700, H. Peter Anvin wrote:
> > On 06/29/16 07:42, Dan Carpenter wrote:
> > > > > and | behave basically the same here but || is intended. It causes a
> > > static checker warning to mix up bitwise and logical operations.
> > >
> > > Signed-off-by: Dan Carpenter <dan.carpen...@oracle.com>
> > >
> > > diff --git a/arch/x86/crypto/sha256-mb/sha256_mb.c
> > > b/arch/x86/crypto/sha256-mb/sha256_mb.c
[]
> > > @@ -299,7 +299,7 @@ static struct sha256_hash_ctx
> > > *sha256_ctx_mgr_submit(struct sha256_ctx_mgr *mgr,
> > > * Or if the user's buffer contains less than a whole block,
> > > * append as much as possible to the extra block.
> > > */
> > > - if ((ctx->partial_block_buffer_length) | (len < SHA256_BLOCK_SIZE)) {
> > > + if ((ctx->partial_block_buffer_length) || (len < SHA256_BLOCK_SIZE)) {
> > > /* Compute how many bytes to copy from user buffer into
> > > * extra block
> > > */
> > >
> > As far as I know the | was an intentional optimization, so you may way
> > to look at the generated code.
> I know how the rules work. I just thought it looked more like a typo
> than an optimization. It's normally a typo. It's hard to tell the
> intent.
The compiler could potentially emit the same code when
optimizing but at least gcc 5.3 doesn't.
It's probably useful to add a comment for the specific intent
here rather than change a potentially useful static checker.
