In spite of the relocation, this sequence is shorter than loading the constant
and symbol_ref independently
when the constant doesn't fit in 14 bits. So, I believe this is a win.
I've also added a REG_EQUAL note to improve optimization.
Tested on hppa-unknown-linux-gnu, hppa2.0w-hp-hpux11.11 and
hppa64-hp-hpux11.11. Committed to
trunk.
Dave
--
John David Anglin dave.ang...@bell.net
2015-02-19 John David Anglin <danl...@gcc.gnu.org>
* config/pa/pa.c (pa_emit_move_sequence): Always force
(const (plus (symbol) (const_int))) to const mem. Put REG_EQUAL
note on insn.
Index: config/pa/pa.c
===================================================================
--- config/pa/pa.c (revision 220778)
+++ config/pa/pa.c (working copy)
@@ -2012,6 +2017,7 @@
if (flag_pic)
{
+ rtx_insn *insn;
rtx temp;
if (reload_in_progress || reload_completed)
@@ -2025,21 +2031,20 @@
else
temp = gen_reg_rtx (Pmode);
- /* (const (plus (symbol) (const_int))) must be forced to
- memory during/after reload if the const_int will not fit
- in 14 bits. */
+ /* Force (const (plus (symbol) (const_int))) to memory
+ if the const_int will not fit in 14 bits. Although
+ this requires a relocation, the instruction sequence
+ needed to load the value is shorter. */
if (GET_CODE (operand1) == CONST
&& GET_CODE (XEXP (operand1, 0)) == PLUS
&& GET_CODE (XEXP (XEXP (operand1, 0), 1)) == CONST_INT
- && !INT_14_BITS (XEXP (XEXP (operand1, 0), 1))
- && (reload_completed || reload_in_progress)
- && flag_pic)
+ && !INT_14_BITS (XEXP (XEXP (operand1, 0), 1)))
{
- rtx const_mem = force_const_mem (mode, operand1);
- operands[1] = legitimize_pic_address (XEXP (const_mem, 0),
- mode, temp);
- operands[1] = replace_equiv_address (const_mem, operands[1]);
- pa_emit_move_sequence (operands, mode, temp);
+ rtx x, m = force_const_mem (mode, operand1);
+
+ x = legitimize_pic_address (XEXP (m, 0), mode, temp);
+ x = replace_equiv_address (m, x);
+ insn = emit_move_insn (operand0, x);
}
else
{
@@ -2046,8 +2051,11 @@
operands[1] = legitimize_pic_address (operand1, mode, temp);
if (REG_P (operand0) && REG_P (operands[1]))
copy_reg_pointer (operand0, operands[1]);
- emit_insn (gen_rtx_SET (VOIDmode, operand0, operands[1]));
+ insn = emit_move_insn (operand0, operands[1]);
}
+
+ /* Put a REG_EQUAL note on this insn. */
+ set_unique_reg_note (insn, REG_EQUAL, operand1);
}
/* On the HPPA, references to data space are supposed to use dp,
register 27, but showing it in the RTL inhibits various cse
