OpenE2K/gcc
2
0
Fork 0
Code Issues Pull Requests Projects Releases Wiki Activity

(output_move_double): Undo 10/25 change.

Browse Source 
(output_move_double): Undo 10/25 change.  Handle case
where part of a dest reg is used in a src mem rtx, without using stack.

From-SVN: r2665
This commit is contained in:
Richard Stallman 1992-10-31 21:17:49 +00:00
parent f9e67232ef
commit 85ddb3994b
1 changed files with 24 additions and 13 deletions
Show Stats Download Patch File Download Diff File Expand all files Collapse all files

37
gcc/config/i386/i386.c
View File

@ -42,7 +42,6 @@ the Free Software Foundation, 675 Mass Ave, Cambridge, MA 02139, USA. */
#define AT_BP(mode) (gen_rtx (MEM, (mode), frame_pointer_rtx))
extern rtx gen_push_operand ();
extern FILE *asm_out_file;
extern char *strcat ();
@ -244,7 +243,7 @@ output_move_double (operands)
enum {REGOP, OFFSOP, MEMOP, PUSHOP, POPOP, CNSTOP, RNDOP } optype0, optype1;
rtx latehalf[2];
rtx addreg0 = 0, addreg1 = 0;
rtx pop_after = 0;
int dest_overlapped_low = 0;
/* First classify both operands. */
@ -355,13 +354,29 @@ output_move_double (operands)
operands[1] = latehalf[1];
/* For (set (reg:DI N) (mem:DI ... (reg:SI N) ...)),
push the first word on the stack, and pop it off afterward. */
if the upper part of reg N does not appear in the MEM, arrange to
emit the move late-half first. Otherwise, compute the MEM address
into the upper part of N and use that as a pointer to the memory
operand. */
if (optype0 == REGOP
&& refers_to_regno_p (REGNO (operands[0]), REGNO (operands[0]) + 1,
operands[1], 0))
&& (optype1 == OFFSOP || optype1 == MEMOP))
{
pop_after = operands[0];
operands[0] = gen_rtx (MEM, SImode, gen_push_operand ());
if (reg_mentioned_p (operands[0], XEXP (operands[1], 0))
&& reg_mentioned_p (latehalf[0], XEXP (operands[1], 0)))
{
/* If both halves of dest are used in the src memory address,
compute the address into latehalf of dest. */
rtx xops[2];
xops[0] = latehalf[0];
xops[1] = XEXP (operands[1], 0);
output_asm_insn (AS2 (lea%L0,%a1,%0), xops);
operands[1] = gen_rtx (MEM, DImode, latehalf[0]);
latehalf[1] = adj_offsettable_operand (operands[1], 4);
}
else if (reg_mentioned_p (operands[0], XEXP (operands[1], 0)))
/* If the low half of dest is mentioned in the source memory
address, the arrange to emit the move late half first. */
dest_overlapped_low = 1;
}
/* If one or both operands autodecrementing,
@ -374,7 +389,8 @@ output_move_double (operands)
if (optype0 == PUSHOP || optype1 == PUSHOP
|| (optype0 == REGOP && optype1 == REGOP
&& REGNO (operands[0]) == REGNO (latehalf[1])))
&& REGNO (operands[0]) == REGNO (latehalf[1]))
|| dest_overlapped_low)
{
/* Make any unoffsettable addresses point at high-numbered word. */
if (addreg0)
@ -414,11 +430,6 @@ output_move_double (operands)
if (addreg1)
asm_add (-4, addreg1);
/* If we diverted a word to the stack, pop it now
to the proper register. */
if (pop_after != 0)
output_asm_insn ("pop%L0 %0", &pop_after);
return "";
}