On Thu, Sep 10, 2020 at 04:58:03PM -0500, Peter Bergner via Gcc-patches wrote:
> +unsigned long
> +test0 (void)
> +{
> + return 0x00ffffffffffff00UL;
> +}
> +
> +unsigned long
> +test1 (void)
> +{
> + return 0x00ffffffff000000UL;
> +}
> +
> +unsigned long
> +test2 (void)
> +{
> + return 0x00ffff0000000000UL;
> +}
> +
> +unsigned long
> +test3 (void)
> +{
> + return 0xffffff0000000000UL;
> +}
> +
> +unsigned long
> +test4 (void)
> +{
> + return 0xffffff000000ffffUL;
> +}
> +
> +unsigned long
> +test5 (void)
> +{
> + return 0x0000010000000000UL;
> +}
> +
> +/* { dg-final { scan-assembler "rldic r?\[0-9\]+,r?\[0-9\]+,8,8" } } */
> +/* { dg-final { scan-assembler "rldic r?\[0-9\]+,r?\[0-9\]+,24,8" } } */
> +/* { dg-final { scan-assembler "rldic r?\[0-9\]+,r?\[0-9\]+,40,8" } } */
> +/* { dg-final { scan-assembler "rldic r?\[0-9\]+,r?\[0-9\]+,40,48" } } */
> +/* { dg-final { scan-assembler "rldic r?\[0-9\]+,r?\[0-9\]+,40,23" } } */
Just a comment, I don't really see too much reason to change anything,
but scan-assembler tests can be a maintenance pain in cases like these
where there are multiple ways to generate a constant in two
instructions. For example,
test3:
li 3,-1
rldicr 3,3,0,23
blr
and
test5:
li 3,16384
rotldi 3,3,26
blr
would be two valid possibilities for test3 and test5 that don't use
rldic. Ideally the test would verify the actual values generated by
the test functions and count instructions.
And having said that I probably ought to post such a testcase for
https://gcc.gnu.org/pipermail/gcc-patches/2020-September/553927.html
I'm sure I had one lying around somewhere...
--
Alan Modra
Australia Development Lab, IBM
