diff options
Diffstat (limited to 'gcc/reg-stack.c')
| -rw-r--r-- | gcc/reg-stack.c | 24 |
1 files changed, 13 insertions, 11 deletions
diff --git a/gcc/reg-stack.c b/gcc/reg-stack.c index c1fc8207ec2..2f94958a2e2 100644 --- a/gcc/reg-stack.c +++ b/gcc/reg-stack.c @@ -1371,21 +1371,23 @@ subst_stack_regs_pat (rtx insn, stack regstack, rtx pat) if (pat != PATTERN (insn)) { - /* The fix_truncdi_1 pattern wants to be able to allocate - its own scratch register. It does this by clobbering - an fp reg so that it is assured of an empty reg-stack - register. If the register is live, kill it now. - Remove the DEAD/UNUSED note so we don't try to kill it - later too. */ + /* The fix_truncdi_1 pattern wants to be able to + allocate its own scratch register. It does this by + clobbering an fp reg so that it is assured of an + empty reg-stack register. If the register is live, + kill it now. Remove the DEAD/UNUSED note so we + don't try to kill it later too. + + In reality the UNUSED note can be absent in some + complicated cases when the register is reused for + partially set variable. */ if (note) emit_pop_insn (insn, regstack, *dest, EMIT_BEFORE); else - { - note = find_reg_note (insn, REG_UNUSED, *dest); - gcc_assert (note); - } - remove_note (insn, note); + note = find_reg_note (insn, REG_UNUSED, *dest); + if (note) + remove_note (insn, note); replace_reg (dest, FIRST_STACK_REG + 1); } else |