Yvan Roux wrote:
Hi,
this patch is a fix for pr27127. It avoids splitting the DI registers
into SI ones if it is not allowed, which breaks the introduced loop.
I haven't added a testcase as the bug is already exhibited by several
regressions (like g++.dg/ext/attribute-test-2.C or g++.dg/eh/simd-1.C)
but I can add one if you think it is needed. Cross built and
regtested on trunk and gcc-5 branch and the regression mentioned in
https://gcc.gnu.org/ml/gcc-patches/2015-07/msg00216.html is not
observed.
Is it ok for trunk and branch ?
Thanks,
Yvan
gcc/
PR target/67127
* config/arm/arm.md (movdi): Avoid forbidden modes changed.
I've just looked into the above 2 testcases on armeb-none-eabi, and in both
cases the infinite loop is due to an ldrd/strd with base register 16. So not an
odd-numbered physical register, but rather something that isn't a physical
register at all.
I observe that FIRST_VIRTUAL_REGISTER is 104, whereas LAST_ARM_REG is 15. So it
might be that the pattern should check against the latter instead of the former
- as arm_hard_regno_mode_ok does...
--Alan
