This patch checks allows immediate then/else operands for cmovs.
We rely on,emit_conditional_move returning NULL if something unsupported
was generated.
Also, minor refactoring is performed.
--
gcc/ChangeLog:
2018-11-14 Robin Dapp <rd...@linux.ibm.com>
* ifcvt.c (have_const_cmov): New function.
(noce_convert_multiple_sets): Allow constants if supported.
(bb_ok_for_noce_convert_multiple_sets): Likewise.
(check_cond_move_block): Refactor.
---
gcc/ifcvt.c | 21 +++++++++++----------
1 file changed, 11 insertions(+), 10 deletions(-)
diff --git a/gcc/ifcvt.c b/gcc/ifcvt.c
index 55205cac153..99716e5f63c 100644
--- a/gcc/ifcvt.c
+++ b/gcc/ifcvt.c
@@ -3214,7 +3214,9 @@ noce_convert_multiple_sets (struct noce_if_info *if_info)
we'll end up trying to emit r4:HI = cond ? (r1:SI) : (r3:HI).
Wrap the two cmove operands into subregs if appropriate to prevent
that. */
- if (GET_MODE (new_val) != GET_MODE (temp))
+
+ if (!CONST_INT_P (new_val)
+ && GET_MODE (new_val) != GET_MODE (temp))
{
machine_mode src_mode = GET_MODE (new_val);
machine_mode dst_mode = GET_MODE (temp);
@@ -3225,7 +3227,8 @@ noce_convert_multiple_sets (struct noce_if_info *if_info)
}
new_val = lowpart_subreg (dst_mode, new_val, src_mode);
}
- if (GET_MODE (old_val) != GET_MODE (temp))
+ if (!CONST_INT_P (old_val)
+ && GET_MODE (old_val) != GET_MODE (temp))
{
machine_mode src_mode = GET_MODE (old_val);
machine_mode dst_mode = GET_MODE (temp);
@@ -3362,9 +3365,9 @@ bb_ok_for_noce_convert_multiple_sets (basic_block
test_bb, unsigned *cost)
if (!REG_P (dest))
return false;
- if (!(REG_P (src)
- || (GET_CODE (src) == SUBREG && REG_P (SUBREG_REG (src))
- && subreg_lowpart_p (src))))
+ if (!((REG_P (src) || (CONST_INT_P (src)))
+ || (GET_CODE (src) == SUBREG && REG_P (SUBREG_REG (src))
+ && subreg_lowpart_p (src))))
return false;
/* Destination must be appropriate for a conditional write. */
@@ -3724,7 +3727,7 @@ check_cond_move_block (basic_block bb,
{
rtx set, dest, src;
- if (!NONDEBUG_INSN_P (insn) || JUMP_P (insn))
+ if (!active_insn_p (insn))
continue;
set = single_set (insn);
if (!set)
@@ -3740,10 +3743,8 @@ check_cond_move_block (basic_block bb,
if (!CONSTANT_P (src) && !register_operand (src, VOIDmode))
return FALSE;
- if (side_effects_p (src) || side_effects_p (dest))
- return FALSE;
-
- if (may_trap_p (src) || may_trap_p (dest))
+ /* Check for side effects and trapping. */
+ if (!noce_operand_ok (src) || !noce_operand_ok (dest))
return FALSE;
/* Don't try to handle this if the source register was
--
2.17.0
