On 27/04/15 00:07, Kugan wrote:
While I support your goals, I think your approach needs some refinement.
In particular, we DO NOT want another function that starts looking at
constant values and tries to decide, on a case by case basis, what to do
with that value. We need to keep the logic for that, as much as
possible, in one small set of functions so that the compiler cannot end
up with conflicting decisions coming from different bits of code.
So const_ok_for_split has to go. Instead you should be using
const_ok_for op (an existing routine) and a simple macro that
encapsulates "optimize >= 2 && can_create_pseudo_p ()" as the gate for
when to use a separate scratch register.
Thanks for the review. Please find the patch attached that does this.
Regression tested on qemu for arm-none-linux-gnueab with no new
regressions. Bootstrapped successfully on chromebook. Is this OK for trunk?
Thanks,
Kugan
gcc/ChangeLog:
2015-04-26 Kugan Vivekanandarajah <kug...@linaro.org>
Zhenqiang Chen <zhenqiang.c...@linaro.org>
PR target/65768
* config/arm/arm.h (CONST_OK_FOR_SPLIT): New macro.
* config/arm/arm.md (subsi3, andsi3, iorsi3, xorsi3, movsi): Keep some
large constants in register instead of splitting them.
I think your macro should be renamed to "DONT_EARLY_SPLIT_CONSTANT" (and
the logic for it inverted, so that you don't need '!' in front of every
instance).
OK with that change.
R.
gcc/testsuite/ChangeLog:
2015-04-26 Kugan Vivekanandarajah <kug...@linaro.org>
Zhenqiang Chen <zhenqiang.c...@linaro.org>
PR target/65768
* gcc.target/arm/maskdata.c: New test.
