Hi,
Is there a way to force the compiler to consider an operand dead?
Specifically, I've got the RL78 backend to generate SET1 and CLR1
instructions to set and clear individual bits. These instructions can
either work on the contents of a specific memory address, or indirectly
by putting the
Hi,
So far I've been testing with hardware but I'm pretty sure I read
somewhere about an RL78 simulator, which would be a useful addition.
Does this simulator exist, and if so, how do I run the tests against it?
I tried 'make -k check RUNTESTFLAGS="--target_board=rl78-sim"' but in
amongst th
On 24/03/14 04:44, Jeff Law wrote:
On 03/22/14 05:29, Richard Hulme wrote:
On 22/03/14 01:47, Jeff Law wrote:
On 03/21/14 18:35, DJ Delorie wrote:
I've found that "removing uneeded moves through registers" is
something gcc does poorly in the post-reload optimizers. I'
On 22/03/14 01:35, DJ Delorie wrote:
Is it possible that the virtual pass causes inefficiencies in some
cases by sticking with r8-r31 when one of the 'normal' registers
would be better?
That's not a fair question to ask, since the virtual pass can *only*
use r8-r31. The first bank has to be le
On 22/03/14 01:47, Jeff Law wrote:
On 03/21/14 18:35, DJ Delorie wrote:
I've found that "removing uneeded moves through registers" is
something gcc does poorly in the post-reload optimizers. I've written
my own on some occasions (for rl78 too). Perhaps this is a good
starting point to look at
On 11/03/14 01:40, DJ Delorie wrote:
I'm curious. Have you tried out other approaches before you decided
to go with the virtual registers?
Yes. Getting GCC to understand the "unusual" addressing modes the
RL78 uses was too much for the register allocator to handle. Even
when the addressing m
On 10/03/14 22:37, DJ Delorie wrote:
The use of "volatile" disables many of GCC's optimizations. I
consider this a bug in GCC, but at the moment it needs to be "fixed"
in the backends on a case-by-case basis.
Hi,
I've looked into the differences between the steps taken when using a
variabl
On 10/03/14 22:37, DJ Delorie wrote:
I've managed to build GCC myself so that I could experiment a bit
but as this is my first foray into compiler internals, I'm
struggling to work out how things fit together and what affects
what.
The key thing to know about the RL78 backend, is that it has tw
