https://gcc.gnu.org/bugzilla/show_bug.cgi?id=100100
Richard Biener <rguenth at gcc dot gnu.org> changed:
What |Removed |Added
----------------------------------------------------------------------------
CC| |jamborm at gcc dot gnu.org
Version|unknown |11.0
Status|UNCONFIRMED |NEW
Keywords| |missed-optimization
Ever confirmed|0 |1
Last reconfirmed| |2021-04-15
--- Comment #1 from Richard Biener <rguenth at gcc dot gnu.org> ---
Different inlining somehow causes different CCP:
-;; Function n (n, funcdef_no=3, decl_uid=1980, cgraph_uid=4, symbol_order=14)
+;; Function j (j, funcdef_no=2, decl_uid=1977, cgraph_uid=3, symbol_order=13)
Adding destination of edge (0 -> 2) to worklist
Simulating block 2
Visiting statement:
-a.0_1 = a;
-which is likely CONSTANT
-Lattice value changed to CONSTANT 0. Adding SSA edges to worklist.
-marking stmt to be not simulated again
-
-Visiting statement:
-_6 = a.0_1 & 65535;
+_8 = q_2(D) & 65535;
which is likely CONSTANT
-Match-and-simplified a.0_1 & 65535 to 0
-Lattice value changed to CONSTANT 0. Adding SSA edges to worklist.
+Lattice value changed to CONSTANT 0x0 (0xffff). Adding SSA edges to worklist.
so we know 'a' is zero (after IPA) but at -O3 a is passed as parameter
(but IPA CP didn't figure out its constant value).
Still odd that the inlining decision is different.
