diff options
Diffstat (limited to 'gcc/ira.c')
| -rw-r--r-- | gcc/ira.c | 14 |
1 files changed, 13 insertions, 1 deletions
@@ -2384,9 +2384,21 @@ update_equiv_regs (void) /* We only handle the case of a pseudo register being set once, or always to the same value. */ + /* ??? The mn10200 port breaks if we add equivalences for + values that need an ADDRESS_REGS register and set them equivalent + to a MEM of a pseudo. The actual problem is in the over-conservative + handling of INPADDR_ADDRESS / INPUT_ADDRESS / INPUT triples in + calculate_needs, but we traditionally work around this problem + here by rejecting equivalences when the destination is in a register + that's likely spilled. This is fragile, of course, since the + preferred class of a pseudo depends on all instructions that set + or use it. */ + if (!REG_P (dest) || (regno = REGNO (dest)) < FIRST_PSEUDO_REGISTER - || reg_equiv[regno].init_insns == const0_rtx) + || reg_equiv[regno].init_insns == const0_rtx + || (CLASS_LIKELY_SPILLED_P (reg_preferred_class (regno)) + && MEM_P (src) && ! reg_equiv[regno].is_arg_equivalence)) { /* This might be setting a SUBREG of a pseudo, a pseudo that is also set somewhere else to a constant. */ |