case CC_OUT_PLUS:
case CC_OUT_PLUS_NOCLOBBER:
+ case CC_LDI:
{
rtx *op = recog_data.operand;
int len_dummy, icc;
/* Extract insn's operands. */
extract_constrain_insn_cached (insn);
- if (CC_OUT_PLUS == cc)
- avr_out_plus (op, &len_dummy, &icc);
- else
- avr_out_plus_noclobber (op, &len_dummy, &icc);
-
- cc = (enum attr_cc) icc;
-
+ switch (cc)
+ {
+ default:
+ gcc_unreachable();
+
+ case CC_OUT_PLUS:
+ avr_out_plus (op, &len_dummy, &icc);
+ cc = (enum attr_cc) icc;
+ break;
+
+ case CC_OUT_PLUS_NOCLOBBER:
+ avr_out_plus_noclobber (op, &len_dummy, &icc);
+ cc = (enum attr_cc) icc;
+ break;
+
+ case CC_LDI:
+
+ cc = (op[1] == CONST0_RTX (GET_MODE (op[0]))
+ && reg_overlap_mentioned_p (op[0], zero_reg_rtx))
+ /* Loading zero-reg with 0 uses CLI and thus clobbers cc0. */
+ ? CC_CLOBBER
+ /* Any other "r,rL" combination does not alter cc0. */
+ : CC_NONE;
+
+ break;
+ } /* inner switch */
+
break;
}
- }
+ } /* outer swicth */
switch (cc)
{
The effect on cc0 is as follows:
- Load 0 to any register : NONE
- Load ld register with any value : NONE
- Anything else: : CLOBBER */
+ Load 0 to any register except ZERO_REG : NONE
+ Load ld register with any value : NONE
+ Anything else: : CLOBBER */
static void
output_reload_in_const (rtx *op, rtx clobber_reg, int *len, bool clear_p)
if (ival[n] == 0)
{
if (!clear_p)
- avr_asm_len (ldreg_p ? "ldi %0,0" : "mov %0,__zero_reg__",
+ avr_asm_len (ldreg_p ? "ldi %0,0"
+ : ZERO_REGNO == REGNO (xdest[n]) ? "clr %0"
+ : "mov %0,__zero_reg__",
&xdest[n], len, 1);
continue;
}
{
/* Default needs 4 CLR instructions: clear register beforehand. */
- avr_asm_len ("clr %A0" CR_TAB
- "clr %B0" CR_TAB
+ avr_asm_len ("mov %A0,__zero_reg__" CR_TAB
+ "mov %B0,__zero_reg__" CR_TAB
"movw %C0,%A0", &op[0], len, 3);
output_reload_in_const (op, clobber_reg, len, true);
;; Condition code settings.
(define_attr "cc" "none,set_czn,set_zn,set_n,compare,clobber,
- out_plus, out_plus_noclobber"
+ out_plus, out_plus_noclobber,ldi"
(const_string "none"))
(define_attr "type" "branch,branch1,arith,xcall"
}
[(set_attr "length" "1,1,5,5,1,1,4")
(set_attr "adjust_len" "mov8")
- (set_attr "cc" "none,none,clobber,clobber,none,none,clobber")])
+ (set_attr "cc" "ldi,none,clobber,clobber,none,none,clobber")])
;; This is used in peephole2 to optimize loading immediate constants
;; if a scratch register from LD_REGS happens to be available.