diff options
| -rw-r--r-- | gcc/ChangeLog | 7 | ||||
| -rw-r--r-- | gcc/reg-stack.c | 61 |
2 files changed, 44 insertions, 24 deletions
diff --git a/gcc/ChangeLog b/gcc/ChangeLog index 97437861d55..b62d1622024 100644 --- a/gcc/ChangeLog +++ b/gcc/ChangeLog @@ -1,5 +1,12 @@ 2004-12-12 Richard Henderson <rth@redhat.com> + PR rtl-opt/17186 + * reg-stack.c (move_nan_for_stack_reg): New. + (subst_stack_regs_pat): Use it. + (move_for_stack_reg): Handle source register not live with a nan. + +2004-12-12 Richard Henderson <rth@redhat.com> + * config/i386/i386.c (ix86_gimplify_va_arg): Fix type mismatch errors across operations. diff --git a/gcc/reg-stack.c b/gcc/reg-stack.c index 5ec8ba5b1b4..d561416fa2c 100644 --- a/gcc/reg-stack.c +++ b/gcc/reg-stack.c @@ -251,6 +251,7 @@ static rtx emit_pop_insn (rtx, stack, rtx, enum emit_where); static void emit_swap_insn (rtx, stack, rtx); static void swap_to_top(rtx, stack, rtx, rtx); static bool move_for_stack_reg (rtx, stack, rtx); +static bool move_nan_for_stack_reg (rtx, stack, rtx); static int swap_rtx_condition_1 (rtx); static int swap_rtx_condition (rtx); static void compare_for_stack_reg (rtx, stack, rtx); @@ -1055,10 +1056,14 @@ move_for_stack_reg (rtx insn, stack regstack, rtx pat) if (regstack->reg[i] == REGNO (src)) break; - /* The source must be live, and the dest must be dead. */ - gcc_assert (i >= 0); + /* The destination must be dead, or life analysis is borked. */ gcc_assert (get_hard_regnum (regstack, dest) < FIRST_STACK_REG); + /* If the source is not live, this is yet another case of + uninitialized variables. Load up a NaN instead. */ + if (i < 0) + return move_nan_for_stack_reg (insn, regstack, dest); + /* It is possible that the dest is unused after this insn. If so, just pop the src. */ @@ -1159,6 +1164,22 @@ move_for_stack_reg (rtx insn, stack regstack, rtx pat) return control_flow_insn_deleted; } + +/* A helper function which replaces INSN with a pattern that loads up + a NaN into DEST, then invokes move_for_stack_reg. */ + +static bool +move_nan_for_stack_reg (rtx insn, stack regstack, rtx dest) +{ + rtx pat; + + dest = FP_MODE_REG (REGNO (dest), SFmode); + pat = gen_rtx_SET (VOIDmode, dest, not_a_num); + PATTERN (insn) = pat; + INSN_CODE (insn) = -1; + + return move_for_stack_reg (insn, regstack, pat); +} /* Swap the condition on a branch, if there is one. Return true if we found a condition to swap. False if the condition was not used as @@ -1430,23 +1451,19 @@ subst_stack_regs_pat (rtx insn, stack regstack, rtx pat) all other clobbers, this must be due to a function returning without a value. Load up a NaN. */ - if (! note - && get_hard_regnum (regstack, *dest) == -1) - { - pat = gen_rtx_SET (VOIDmode, - FP_MODE_REG (REGNO (*dest), SFmode), - not_a_num); - PATTERN (insn) = pat; - control_flow_insn_deleted |= move_for_stack_reg (insn, regstack, pat); - } - if (! note && COMPLEX_MODE_P (GET_MODE (*dest)) - && get_hard_regnum (regstack, FP_MODE_REG (REGNO (*dest), DFmode)) == -1) + if (!note) { - pat = gen_rtx_SET (VOIDmode, - FP_MODE_REG (REGNO (*dest) + 1, SFmode), - not_a_num); - PATTERN (insn) = pat; - control_flow_insn_deleted |= move_for_stack_reg (insn, regstack, pat); + rtx t = *dest; + if (get_hard_regnum (regstack, t) == -1) + control_flow_insn_deleted + |= move_nan_for_stack_reg (insn, regstack, t); + if (COMPLEX_MODE_P (GET_MODE (t))) + { + t = FP_MODE_REG (REGNO (t) + 1, DFmode); + if (get_hard_regnum (regstack, t) == -1) + control_flow_insn_deleted + |= move_nan_for_stack_reg (insn, regstack, t); + } } } } @@ -2921,13 +2938,9 @@ convert_regs_1 (FILE *file, basic_block block) rtx set; if (file) - { - fprintf (file, "Emitting insn initializing reg %d\n", - reg); - } + fprintf (file, "Emitting insn initializing reg %d\n", reg); - set = gen_rtx_SET (VOIDmode, FP_MODE_REG (reg, SFmode), - not_a_num); + set = gen_rtx_SET (VOIDmode, FP_MODE_REG (reg, SFmode), not_a_num); insn = emit_insn_after (set, insn); control_flow_insn_deleted |= subst_stack_regs (insn, ®stack); } |