On sh (and other targets with no variable shift): typedef unsigned long long ull; ull foo (ull x, int y) { return x << y; }
is implemented using several calls to the SImode shift routines, rather than one call to the DImode routine. A similar problem affects constant shifts if the target does not have a direct implementation. 3.4 did not have this problem; it's a 4.x regression introduced by my 2004-09-04 patch. -- Summary: [4.0/4.1/4.2 Regression] Doubleword shifts implemented using word_mode libcalls Product: gcc Version: 4.0.0 Status: UNCONFIRMED Keywords: missed-optimization Severity: normal Priority: P3 Component: middle-end AssignedTo: unassigned at gcc dot gnu dot org ReportedBy: rsandifo at gcc dot gnu dot org GCC target triplet: sh-elf http://gcc.gnu.org/bugzilla/show_bug.cgi?id=28402