+ emit_swap_insn (insn, regstack, *src1);
+
+ /* Input should never die, it is replaced with output. */
+ src1_note = find_regno_note (insn, REG_DEAD, REGNO (*src1));
+ gcc_assert (!src1_note);
+
+ if (STACK_REG_P (*dest))
+ replace_reg (dest, FIRST_STACK_REG);
+
+ replace_reg (src1, FIRST_STACK_REG);
+ break;
+
+ case UNSPEC_SINCOS_SIN:
+ case UNSPEC_XTRACT_EXP:
+
+ /* These insns operate on the top two stack slots,
+ second part of one input, double output insn. */
+
+ regstack->top++;
+ /* FALLTHRU */
+
+ case UNSPEC_TAN:
+
+ /* For UNSPEC_TAN, regstack->top is already increased
+ by inherent load of constant 1.0. */
+
+ /* Output value is generated in the second stack slot.
+ Move current value from second slot to the top. */
+ regstack->reg[regstack->top]
+ = regstack->reg[regstack->top - 1];
+
+ gcc_assert (STACK_REG_P (*dest));
+
+ regstack->reg[regstack->top - 1] = REGNO (*dest);
+ SET_HARD_REG_BIT (regstack->reg_set, REGNO (*dest));
+ replace_reg (dest, FIRST_STACK_REG + 1);
+
+ src1 = get_true_reg (&XVECEXP (pat_src, 0, 0));
+
+ replace_reg (src1, FIRST_STACK_REG);
+ break;
+
+ case UNSPEC_FPATAN:
+ case UNSPEC_FYL2X:
+ case UNSPEC_FYL2XP1:
+ /* These insns operate on the top two stack slots. */
+
+ src1 = get_true_reg (&XVECEXP (pat_src, 0, 0));
+ src2 = get_true_reg (&XVECEXP (pat_src, 0, 1));
+
+ src1_note = find_regno_note (insn, REG_DEAD, REGNO (*src1));
+ src2_note = find_regno_note (insn, REG_DEAD, REGNO (*src2));
+
+ swap_to_top (insn, regstack, *src1, *src2);
+
+ replace_reg (src1, FIRST_STACK_REG);
+ replace_reg (src2, FIRST_STACK_REG + 1);
+
+ if (src1_note)
+ replace_reg (&XEXP (src1_note, 0), FIRST_STACK_REG);
+ if (src2_note)
+ replace_reg (&XEXP (src2_note, 0), FIRST_STACK_REG + 1);
+
+ /* Pop both input operands from the stack. */
+ CLEAR_HARD_REG_BIT (regstack->reg_set,
+ regstack->reg[regstack->top]);
+ CLEAR_HARD_REG_BIT (regstack->reg_set,
+ regstack->reg[regstack->top - 1]);
+ regstack->top -= 2;
+
+ /* Push the result back onto the stack. */
+ regstack->reg[++regstack->top] = REGNO (*dest);
+ SET_HARD_REG_BIT (regstack->reg_set, REGNO (*dest));
+ replace_reg (dest, FIRST_STACK_REG);
+ break;
+
+ case UNSPEC_FSCALE_FRACT:
+ case UNSPEC_FPREM_F:
+ case UNSPEC_FPREM1_F:
+ /* These insns operate on the top two stack slots,
+ first part of double input, double output insn. */
+
+ src1 = get_true_reg (&XVECEXP (pat_src, 0, 0));
+ src2 = get_true_reg (&XVECEXP (pat_src, 0, 1));
+
+ src1_note = find_regno_note (insn, REG_DEAD, REGNO (*src1));
+ src2_note = find_regno_note (insn, REG_DEAD, REGNO (*src2));
+
+ /* Inputs should never die, they are
+ replaced with outputs. */
+ gcc_assert (!src1_note);
+ gcc_assert (!src2_note);
+
+ swap_to_top (insn, regstack, *src1, *src2);
+
+ /* Push the result back onto stack. Empty stack slot
+ will be filled in second part of insn. */
+ if (STACK_REG_P (*dest))
+ {
+ regstack->reg[regstack->top] = REGNO (*dest);
+ SET_HARD_REG_BIT (regstack->reg_set, REGNO (*dest));
+ replace_reg (dest, FIRST_STACK_REG);
+ }
+
+ replace_reg (src1, FIRST_STACK_REG);
+ replace_reg (src2, FIRST_STACK_REG + 1);
+ break;
+
+ case UNSPEC_FSCALE_EXP:
+ case UNSPEC_FPREM_U:
+ case UNSPEC_FPREM1_U:
+ /* These insns operate on the top two stack slots,
+ second part of double input, double output insn. */
+
+ src1 = get_true_reg (&XVECEXP (pat_src, 0, 0));
+ src2 = get_true_reg (&XVECEXP (pat_src, 0, 1));
+
+ /* Push the result back onto stack. Fill empty slot from
+ first part of insn and fix top of stack pointer. */
+ if (STACK_REG_P (*dest))
+ {
+ regstack->reg[regstack->top - 1] = REGNO (*dest);
+ SET_HARD_REG_BIT (regstack->reg_set, REGNO (*dest));
+ replace_reg (dest, FIRST_STACK_REG + 1);
+ }
+
+ replace_reg (src1, FIRST_STACK_REG);
+ replace_reg (src2, FIRST_STACK_REG + 1);
+ break;
+
+ case UNSPEC_C2_FLAG:
+ /* This insn operates on the top two stack slots,
+ third part of C2 setting double input insn. */
+
+ src1 = get_true_reg (&XVECEXP (pat_src, 0, 0));
+ src2 = get_true_reg (&XVECEXP (pat_src, 0, 1));
+
+ replace_reg (src1, FIRST_STACK_REG);
+ replace_reg (src2, FIRST_STACK_REG + 1);
+ break;
+
+ case UNSPEC_SAHF:
+ /* (unspec [(unspec [(compare)] UNSPEC_FNSTSW)] UNSPEC_SAHF)
+ The combination matches the PPRO fcomi instruction. */
+
+ pat_src = XVECEXP (pat_src, 0, 0);
+ gcc_assert (GET_CODE (pat_src) == UNSPEC);
+ gcc_assert (XINT (pat_src, 1) == UNSPEC_FNSTSW);
+ /* Fall through. */
+
+ case UNSPEC_FNSTSW:
+ /* Combined fcomp+fnstsw generated for doing well with
+ CSE. When optimizing this would have been broken
+ up before now. */
+
+ pat_src = XVECEXP (pat_src, 0, 0);
+ gcc_assert (GET_CODE (pat_src) == COMPARE);
+
+ compare_for_stack_reg (insn, regstack, pat_src);
+ break;
+
+ default:
+ gcc_unreachable ();
+ }
+ break;
+
+ case IF_THEN_ELSE:
+ /* This insn requires the top of stack to be the destination. */
+
+ src1 = get_true_reg (&XEXP (pat_src, 1));
+ src2 = get_true_reg (&XEXP (pat_src, 2));
+
+ src1_note = find_regno_note (insn, REG_DEAD, REGNO (*src1));
+ src2_note = find_regno_note (insn, REG_DEAD, REGNO (*src2));
+
+ /* If the comparison operator is an FP comparison operator,
+ it is handled correctly by compare_for_stack_reg () who
+ will move the destination to the top of stack. But if the
+ comparison operator is not an FP comparison operator, we
+ have to handle it here. */
+ if (get_hard_regnum (regstack, *dest) >= FIRST_STACK_REG
+ && REGNO (*dest) != regstack->reg[regstack->top])
+ {
+ /* In case one of operands is the top of stack and the operands
+ dies, it is safe to make it the destination operand by
+ reversing the direction of cmove and avoid fxch. */
+ if ((REGNO (*src1) == regstack->reg[regstack->top]
+ && src1_note)
+ || (REGNO (*src2) == regstack->reg[regstack->top]
+ && src2_note))
+ {
+ int idx1 = (get_hard_regnum (regstack, *src1)
+ - FIRST_STACK_REG);
+ int idx2 = (get_hard_regnum (regstack, *src2)
+ - FIRST_STACK_REG);
+
+ /* Make reg-stack believe that the operands are already
+ swapped on the stack */
+ regstack->reg[regstack->top - idx1] = REGNO (*src2);
+ regstack->reg[regstack->top - idx2] = REGNO (*src1);
+
+ /* Reverse condition to compensate the operand swap.
+ i386 do have comparison always reversible. */
+ PUT_CODE (XEXP (pat_src, 0),
+ reversed_comparison_code (XEXP (pat_src, 0), insn));
+ }
+ else
+ emit_swap_insn (insn, regstack, *dest);
+ }
+
+ {
+ rtx src_note [3];
+ int i;
+
+ src_note[0] = 0;
+ src_note[1] = src1_note;
+ src_note[2] = src2_note;
+
+ if (STACK_REG_P (*src1))
+ replace_reg (src1, get_hard_regnum (regstack, *src1));
+ if (STACK_REG_P (*src2))
+ replace_reg (src2, get_hard_regnum (regstack, *src2));
+
+ for (i = 1; i <= 2; i++)