https://gcc.gnu.org/bugzilla/show_bug.cgi?id=102239
--- Comment #7 from luoxhu at gcc dot gnu.org ---
1| Dump of assembler code for function foo:
2| 0x00000000100005e0 <+0>: rldicr. r3,r3,29,1
3+> 0x00000000100005e4 <+4>: beq 0x100005f0 <foo+16>
4| 0x00000000100005e8 <+8>: blr
5| 0x00000000100005ec <+12>: ori r2,r2,0
6| 0x00000000100005f0 <+16>: blr
7| 0x00000000100005f4 <+20>: .long 0x0
8| 0x00000000100005f8 <+24>: .long 0x0
(gdb) si
0x00000000100005e4 in foo ()
1: /x $r3 = 0xc000000000000000
2: /x $cr = 0x82000282
cr0 is negative if only rotldi3_mask_dot, but it was 0x42000282 on master code.
BTW, clang also generated instructions with two rorates:
foo(long): # @foo(long)
rldicl 3, 3, 31, 33
rldicl. 3, 3, 33, 29
beq 0, .LBB0_2
blr
.LBB0_2:
blr
.long 0
.quad 0
