1052 lines
32 KiB
C
1052 lines
32 KiB
C
/* Convert tree expression to rtl instructions, for GNU compiler.
|
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Copyright (C) 1988, 1992, 1993, 1994, 1995, 1996, 1997, 1998, 1999,
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2000, 2001, 2002, 2003, 2004, 2005, 2006 Free Software Foundation, Inc.
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|
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This file is part of GCC.
|
||
|
||
GCC is free software; you can redistribute it and/or modify it under
|
||
the terms of the GNU General Public License as published by the Free
|
||
Software Foundation; either version 2, or (at your option) any later
|
||
version.
|
||
|
||
GCC is distributed in the hope that it will be useful, but WITHOUT ANY
|
||
WARRANTY; without even the implied warranty of MERCHANTABILITY or
|
||
FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
|
||
for more details.
|
||
|
||
You should have received a copy of the GNU General Public License
|
||
along with GCC; see the file COPYING. If not, write to the Free
|
||
Software Foundation, 51 Franklin Street, Fifth Floor, Boston, MA
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02110-1301, USA. */
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#include "config.h"
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#include "system.h"
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#include "coretypes.h"
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#include "tm.h"
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#include "rtl.h"
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#include "tree.h"
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#include "flags.h"
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#include "function.h"
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#include "insn-config.h"
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#include "insn-attr.h"
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/* Include expr.h after insn-config.h so we get HAVE_conditional_move. */
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#include "expr.h"
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#include "optabs.h"
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#include "langhooks.h"
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||
#include "ggc.h"
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static bool prefer_and_bit_test (enum machine_mode, int);
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static void do_jump_by_parts_greater (tree, int, rtx, rtx);
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||
static void do_jump_by_parts_equality (tree, rtx, rtx);
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||
static void do_compare_and_jump (tree, enum rtx_code, enum rtx_code, rtx,
|
||
rtx);
|
||
|
||
/* At the start of a function, record that we have no previously-pushed
|
||
arguments waiting to be popped. */
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||
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||
void
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||
init_pending_stack_adjust (void)
|
||
{
|
||
pending_stack_adjust = 0;
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||
}
|
||
|
||
/* Discard any pending stack adjustment. This avoid relying on the
|
||
RTL optimizers to remove useless adjustments when we know the
|
||
stack pointer value is dead. */
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||
void
|
||
discard_pending_stack_adjust (void)
|
||
{
|
||
stack_pointer_delta -= pending_stack_adjust;
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||
pending_stack_adjust = 0;
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||
}
|
||
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||
/* When exiting from function, if safe, clear out any pending stack adjust
|
||
so the adjustment won't get done.
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||
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||
Note, if the current function calls alloca, then it must have a
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||
frame pointer regardless of the value of flag_omit_frame_pointer. */
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||
|
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void
|
||
clear_pending_stack_adjust (void)
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||
{
|
||
if (optimize > 0
|
||
&& (! flag_omit_frame_pointer || current_function_calls_alloca)
|
||
&& EXIT_IGNORE_STACK
|
||
&& ! (DECL_INLINE (current_function_decl) && ! flag_no_inline))
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||
discard_pending_stack_adjust ();
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||
}
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||
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||
/* Pop any previously-pushed arguments that have not been popped yet. */
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||
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||
void
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||
do_pending_stack_adjust (void)
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{
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||
if (inhibit_defer_pop == 0)
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{
|
||
if (pending_stack_adjust != 0)
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adjust_stack (GEN_INT (pending_stack_adjust));
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pending_stack_adjust = 0;
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||
}
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||
}
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||
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/* Expand conditional expressions. */
|
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/* Generate code to evaluate EXP and jump to LABEL if the value is zero.
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LABEL is an rtx of code CODE_LABEL, in this function and all the
|
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functions here. */
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void
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||
jumpifnot (tree exp, rtx label)
|
||
{
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||
do_jump (exp, label, NULL_RTX);
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||
}
|
||
|
||
/* Generate code to evaluate EXP and jump to LABEL if the value is nonzero. */
|
||
|
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void
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||
jumpif (tree exp, rtx label)
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||
{
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||
do_jump (exp, NULL_RTX, label);
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||
}
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||
|
||
/* Used internally by prefer_and_bit_test. */
|
||
|
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static GTY(()) rtx and_reg;
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static GTY(()) rtx and_test;
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||
static GTY(()) rtx shift_test;
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||
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/* Compare the relative costs of "(X & (1 << BITNUM))" and "(X >> BITNUM) & 1",
|
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where X is an arbitrary register of mode MODE. Return true if the former
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is preferred. */
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static bool
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prefer_and_bit_test (enum machine_mode mode, int bitnum)
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{
|
||
if (and_test == 0)
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{
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/* Set up rtxes for the two variations. Use NULL as a placeholder
|
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for the BITNUM-based constants. */
|
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and_reg = gen_rtx_REG (mode, FIRST_PSEUDO_REGISTER);
|
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and_test = gen_rtx_AND (mode, and_reg, NULL);
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shift_test = gen_rtx_AND (mode, gen_rtx_ASHIFTRT (mode, and_reg, NULL),
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const1_rtx);
|
||
}
|
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else
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||
{
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||
/* Change the mode of the previously-created rtxes. */
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PUT_MODE (and_reg, mode);
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PUT_MODE (and_test, mode);
|
||
PUT_MODE (shift_test, mode);
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||
PUT_MODE (XEXP (shift_test, 0), mode);
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||
}
|
||
|
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/* Fill in the integers. */
|
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XEXP (and_test, 1) = GEN_INT ((unsigned HOST_WIDE_INT) 1 << bitnum);
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XEXP (XEXP (shift_test, 0), 1) = GEN_INT (bitnum);
|
||
|
||
return (rtx_cost (and_test, IF_THEN_ELSE)
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<= rtx_cost (shift_test, IF_THEN_ELSE));
|
||
}
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/* Generate code to evaluate EXP and jump to IF_FALSE_LABEL if
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the result is zero, or IF_TRUE_LABEL if the result is one.
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Either of IF_FALSE_LABEL and IF_TRUE_LABEL may be zero,
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meaning fall through in that case.
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||
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do_jump always does any pending stack adjust except when it does not
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actually perform a jump. An example where there is no jump
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is when EXP is `(foo (), 0)' and IF_FALSE_LABEL is null. */
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void
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do_jump (tree exp, rtx if_false_label, rtx if_true_label)
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{
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enum tree_code code = TREE_CODE (exp);
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rtx temp;
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int i;
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tree type;
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enum machine_mode mode;
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rtx drop_through_label = 0;
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||
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switch (code)
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{
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case ERROR_MARK:
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break;
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case INTEGER_CST:
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temp = integer_zerop (exp) ? if_false_label : if_true_label;
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if (temp)
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emit_jump (temp);
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break;
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#if 0
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/* This is not true with #pragma weak */
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case ADDR_EXPR:
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/* The address of something can never be zero. */
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if (if_true_label)
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emit_jump (if_true_label);
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break;
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#endif
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||
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case NOP_EXPR:
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if (TREE_CODE (TREE_OPERAND (exp, 0)) == COMPONENT_REF
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||
|| TREE_CODE (TREE_OPERAND (exp, 0)) == BIT_FIELD_REF
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||
|| TREE_CODE (TREE_OPERAND (exp, 0)) == ARRAY_REF
|
||
|| TREE_CODE (TREE_OPERAND (exp, 0)) == ARRAY_RANGE_REF)
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||
goto normal;
|
||
case CONVERT_EXPR:
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||
/* If we are narrowing the operand, we have to do the compare in the
|
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narrower mode. */
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if ((TYPE_PRECISION (TREE_TYPE (exp))
|
||
< TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp, 0)))))
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||
goto normal;
|
||
case NON_LVALUE_EXPR:
|
||
case ABS_EXPR:
|
||
case NEGATE_EXPR:
|
||
case LROTATE_EXPR:
|
||
case RROTATE_EXPR:
|
||
/* These cannot change zero->nonzero or vice versa. */
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do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
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||
break;
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||
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case BIT_AND_EXPR:
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/* fold_single_bit_test() converts (X & (1 << C)) into (X >> C) & 1.
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See if the former is preferred for jump tests and restore it
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if so. */
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if (integer_onep (TREE_OPERAND (exp, 1)))
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||
{
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tree exp0 = TREE_OPERAND (exp, 0);
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rtx set_label, clr_label;
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||
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/* Strip narrowing integral type conversions. */
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while ((TREE_CODE (exp0) == NOP_EXPR
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|| TREE_CODE (exp0) == CONVERT_EXPR
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|| TREE_CODE (exp0) == NON_LVALUE_EXPR)
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&& TREE_OPERAND (exp0, 0) != error_mark_node
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&& TYPE_PRECISION (TREE_TYPE (exp0))
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<= TYPE_PRECISION (TREE_TYPE (TREE_OPERAND (exp0, 0))))
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exp0 = TREE_OPERAND (exp0, 0);
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/* "exp0 ^ 1" inverts the sense of the single bit test. */
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if (TREE_CODE (exp0) == BIT_XOR_EXPR
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&& integer_onep (TREE_OPERAND (exp0, 1)))
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{
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exp0 = TREE_OPERAND (exp0, 0);
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clr_label = if_true_label;
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set_label = if_false_label;
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}
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else
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{
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clr_label = if_false_label;
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set_label = if_true_label;
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}
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if (TREE_CODE (exp0) == RSHIFT_EXPR)
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{
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tree arg = TREE_OPERAND (exp0, 0);
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tree shift = TREE_OPERAND (exp0, 1);
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tree argtype = TREE_TYPE (arg);
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if (TREE_CODE (shift) == INTEGER_CST
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&& compare_tree_int (shift, 0) >= 0
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&& compare_tree_int (shift, HOST_BITS_PER_WIDE_INT) < 0
|
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&& prefer_and_bit_test (TYPE_MODE (argtype),
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TREE_INT_CST_LOW (shift)))
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{
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HOST_WIDE_INT mask = (HOST_WIDE_INT) 1
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<< TREE_INT_CST_LOW (shift);
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do_jump (build2 (BIT_AND_EXPR, argtype, arg,
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build_int_cst_type (argtype, mask)),
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clr_label, set_label);
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||
break;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* If we are AND'ing with a small constant, do this comparison in the
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smallest type that fits. If the machine doesn't have comparisons
|
||
that small, it will be converted back to the wider comparison.
|
||
This helps if we are testing the sign bit of a narrower object.
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||
combine can't do this for us because it can't know whether a
|
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ZERO_EXTRACT or a compare in a smaller mode exists, but we do. */
|
||
|
||
if (! SLOW_BYTE_ACCESS
|
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&& TREE_CODE (TREE_OPERAND (exp, 1)) == INTEGER_CST
|
||
&& TYPE_PRECISION (TREE_TYPE (exp)) <= HOST_BITS_PER_WIDE_INT
|
||
&& (i = tree_floor_log2 (TREE_OPERAND (exp, 1))) >= 0
|
||
&& (mode = mode_for_size (i + 1, MODE_INT, 0)) != BLKmode
|
||
&& (type = lang_hooks.types.type_for_mode (mode, 1)) != 0
|
||
&& TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (exp))
|
||
&& (cmp_optab->handlers[(int) TYPE_MODE (type)].insn_code
|
||
!= CODE_FOR_nothing))
|
||
{
|
||
do_jump (fold_convert (type, exp), if_false_label, if_true_label);
|
||
break;
|
||
}
|
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goto normal;
|
||
|
||
case TRUTH_NOT_EXPR:
|
||
do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label);
|
||
break;
|
||
|
||
case COND_EXPR:
|
||
{
|
||
rtx label1 = gen_label_rtx ();
|
||
if (!if_true_label || !if_false_label)
|
||
{
|
||
drop_through_label = gen_label_rtx ();
|
||
if (!if_true_label)
|
||
if_true_label = drop_through_label;
|
||
if (!if_false_label)
|
||
if_false_label = drop_through_label;
|
||
}
|
||
|
||
do_pending_stack_adjust ();
|
||
do_jump (TREE_OPERAND (exp, 0), label1, NULL_RTX);
|
||
do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
|
||
emit_label (label1);
|
||
do_jump (TREE_OPERAND (exp, 2), if_false_label, if_true_label);
|
||
break;
|
||
}
|
||
|
||
case TRUTH_ANDIF_EXPR:
|
||
case TRUTH_ORIF_EXPR:
|
||
case COMPOUND_EXPR:
|
||
/* Lowered by gimplify.c. */
|
||
gcc_unreachable ();
|
||
|
||
case COMPONENT_REF:
|
||
case BIT_FIELD_REF:
|
||
case ARRAY_REF:
|
||
case ARRAY_RANGE_REF:
|
||
{
|
||
HOST_WIDE_INT bitsize, bitpos;
|
||
int unsignedp;
|
||
enum machine_mode mode;
|
||
tree type;
|
||
tree offset;
|
||
int volatilep = 0;
|
||
|
||
/* Get description of this reference. We don't actually care
|
||
about the underlying object here. */
|
||
get_inner_reference (exp, &bitsize, &bitpos, &offset, &mode,
|
||
&unsignedp, &volatilep, false);
|
||
|
||
type = lang_hooks.types.type_for_size (bitsize, unsignedp);
|
||
if (! SLOW_BYTE_ACCESS
|
||
&& type != 0 && bitsize >= 0
|
||
&& TYPE_PRECISION (type) < TYPE_PRECISION (TREE_TYPE (exp))
|
||
&& (cmp_optab->handlers[(int) TYPE_MODE (type)].insn_code
|
||
!= CODE_FOR_nothing))
|
||
{
|
||
do_jump (fold_convert (type, exp), if_false_label, if_true_label);
|
||
break;
|
||
}
|
||
goto normal;
|
||
}
|
||
|
||
case EQ_EXPR:
|
||
{
|
||
tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0));
|
||
|
||
gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
|
||
!= MODE_COMPLEX_FLOAT);
|
||
gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
|
||
!= MODE_COMPLEX_INT);
|
||
|
||
if (integer_zerop (TREE_OPERAND (exp, 1)))
|
||
do_jump (TREE_OPERAND (exp, 0), if_true_label, if_false_label);
|
||
else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT
|
||
&& !can_compare_p (EQ, TYPE_MODE (inner_type), ccp_jump))
|
||
do_jump_by_parts_equality (exp, if_false_label, if_true_label);
|
||
else
|
||
do_compare_and_jump (exp, EQ, EQ, if_false_label, if_true_label);
|
||
break;
|
||
}
|
||
|
||
case MINUS_EXPR:
|
||
/* Nonzero iff operands of minus differ. */
|
||
exp = build2 (NE_EXPR, TREE_TYPE (exp),
|
||
TREE_OPERAND (exp, 0),
|
||
TREE_OPERAND (exp, 1));
|
||
/* FALLTHRU */
|
||
case NE_EXPR:
|
||
{
|
||
tree inner_type = TREE_TYPE (TREE_OPERAND (exp, 0));
|
||
|
||
gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
|
||
!= MODE_COMPLEX_FLOAT);
|
||
gcc_assert (GET_MODE_CLASS (TYPE_MODE (inner_type))
|
||
!= MODE_COMPLEX_INT);
|
||
|
||
if (integer_zerop (TREE_OPERAND (exp, 1)))
|
||
do_jump (TREE_OPERAND (exp, 0), if_false_label, if_true_label);
|
||
else if (GET_MODE_CLASS (TYPE_MODE (inner_type)) == MODE_INT
|
||
&& !can_compare_p (NE, TYPE_MODE (inner_type), ccp_jump))
|
||
do_jump_by_parts_equality (exp, if_true_label, if_false_label);
|
||
else
|
||
do_compare_and_jump (exp, NE, NE, if_false_label, if_true_label);
|
||
break;
|
||
}
|
||
|
||
case LT_EXPR:
|
||
mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
if (GET_MODE_CLASS (mode) == MODE_INT
|
||
&& ! can_compare_p (LT, mode, ccp_jump))
|
||
do_jump_by_parts_greater (exp, 1, if_false_label, if_true_label);
|
||
else
|
||
do_compare_and_jump (exp, LT, LTU, if_false_label, if_true_label);
|
||
break;
|
||
|
||
case LE_EXPR:
|
||
mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
if (GET_MODE_CLASS (mode) == MODE_INT
|
||
&& ! can_compare_p (LE, mode, ccp_jump))
|
||
do_jump_by_parts_greater (exp, 0, if_true_label, if_false_label);
|
||
else
|
||
do_compare_and_jump (exp, LE, LEU, if_false_label, if_true_label);
|
||
break;
|
||
|
||
case GT_EXPR:
|
||
mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
if (GET_MODE_CLASS (mode) == MODE_INT
|
||
&& ! can_compare_p (GT, mode, ccp_jump))
|
||
do_jump_by_parts_greater (exp, 0, if_false_label, if_true_label);
|
||
else
|
||
do_compare_and_jump (exp, GT, GTU, if_false_label, if_true_label);
|
||
break;
|
||
|
||
case GE_EXPR:
|
||
mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
if (GET_MODE_CLASS (mode) == MODE_INT
|
||
&& ! can_compare_p (GE, mode, ccp_jump))
|
||
do_jump_by_parts_greater (exp, 1, if_true_label, if_false_label);
|
||
else
|
||
do_compare_and_jump (exp, GE, GEU, if_false_label, if_true_label);
|
||
break;
|
||
|
||
case UNORDERED_EXPR:
|
||
case ORDERED_EXPR:
|
||
{
|
||
enum rtx_code cmp, rcmp;
|
||
int do_rev;
|
||
|
||
if (code == UNORDERED_EXPR)
|
||
cmp = UNORDERED, rcmp = ORDERED;
|
||
else
|
||
cmp = ORDERED, rcmp = UNORDERED;
|
||
mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
|
||
do_rev = 0;
|
||
if (! can_compare_p (cmp, mode, ccp_jump)
|
||
&& (can_compare_p (rcmp, mode, ccp_jump)
|
||
/* If the target doesn't provide either UNORDERED or ORDERED
|
||
comparisons, canonicalize on UNORDERED for the library. */
|
||
|| rcmp == UNORDERED))
|
||
do_rev = 1;
|
||
|
||
if (! do_rev)
|
||
do_compare_and_jump (exp, cmp, cmp, if_false_label, if_true_label);
|
||
else
|
||
do_compare_and_jump (exp, rcmp, rcmp, if_true_label, if_false_label);
|
||
}
|
||
break;
|
||
|
||
{
|
||
enum rtx_code rcode1;
|
||
enum tree_code tcode1, tcode2;
|
||
|
||
case UNLT_EXPR:
|
||
rcode1 = UNLT;
|
||
tcode1 = UNORDERED_EXPR;
|
||
tcode2 = LT_EXPR;
|
||
goto unordered_bcc;
|
||
case UNLE_EXPR:
|
||
rcode1 = UNLE;
|
||
tcode1 = UNORDERED_EXPR;
|
||
tcode2 = LE_EXPR;
|
||
goto unordered_bcc;
|
||
case UNGT_EXPR:
|
||
rcode1 = UNGT;
|
||
tcode1 = UNORDERED_EXPR;
|
||
tcode2 = GT_EXPR;
|
||
goto unordered_bcc;
|
||
case UNGE_EXPR:
|
||
rcode1 = UNGE;
|
||
tcode1 = UNORDERED_EXPR;
|
||
tcode2 = GE_EXPR;
|
||
goto unordered_bcc;
|
||
case UNEQ_EXPR:
|
||
rcode1 = UNEQ;
|
||
tcode1 = UNORDERED_EXPR;
|
||
tcode2 = EQ_EXPR;
|
||
goto unordered_bcc;
|
||
case LTGT_EXPR:
|
||
/* It is ok for LTGT_EXPR to trap when the result is unordered,
|
||
so expand to (a < b) || (a > b). */
|
||
rcode1 = LTGT;
|
||
tcode1 = LT_EXPR;
|
||
tcode2 = GT_EXPR;
|
||
goto unordered_bcc;
|
||
|
||
unordered_bcc:
|
||
mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
if (can_compare_p (rcode1, mode, ccp_jump))
|
||
do_compare_and_jump (exp, rcode1, rcode1, if_false_label,
|
||
if_true_label);
|
||
else
|
||
{
|
||
tree op0 = save_expr (TREE_OPERAND (exp, 0));
|
||
tree op1 = save_expr (TREE_OPERAND (exp, 1));
|
||
tree cmp0, cmp1;
|
||
|
||
/* If the target doesn't support combined unordered
|
||
compares, decompose into two comparisons. */
|
||
if (if_true_label == 0)
|
||
drop_through_label = if_true_label = gen_label_rtx ();
|
||
|
||
cmp0 = fold_build2 (tcode1, TREE_TYPE (exp), op0, op1);
|
||
cmp1 = fold_build2 (tcode2, TREE_TYPE (exp), op0, op1);
|
||
do_jump (cmp0, 0, if_true_label);
|
||
do_jump (cmp1, if_false_label, if_true_label);
|
||
}
|
||
}
|
||
break;
|
||
|
||
case TRUTH_AND_EXPR:
|
||
/* High branch cost, expand as the bitwise AND of the conditions.
|
||
Do the same if the RHS has side effects, because we're effectively
|
||
turning a TRUTH_AND_EXPR into a TRUTH_ANDIF_EXPR. */
|
||
if (BRANCH_COST >= 4 || TREE_SIDE_EFFECTS (TREE_OPERAND (exp, 1)))
|
||
goto normal;
|
||
|
||
if (if_false_label == NULL_RTX)
|
||
{
|
||
drop_through_label = gen_label_rtx ();
|
||
do_jump (TREE_OPERAND (exp, 0), drop_through_label, NULL_RTX);
|
||
do_jump (TREE_OPERAND (exp, 1), NULL_RTX, if_true_label);
|
||
}
|
||
else
|
||
{
|
||
do_jump (TREE_OPERAND (exp, 0), if_false_label, NULL_RTX);
|
||
do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
|
||
}
|
||
break;
|
||
|
||
case TRUTH_OR_EXPR:
|
||
/* High branch cost, expand as the bitwise OR of the conditions.
|
||
Do the same if the RHS has side effects, because we're effectively
|
||
turning a TRUTH_OR_EXPR into a TRUTH_ORIF_EXPR. */
|
||
if (BRANCH_COST >= 4 || TREE_SIDE_EFFECTS (TREE_OPERAND (exp, 1)))
|
||
goto normal;
|
||
|
||
if (if_true_label == NULL_RTX)
|
||
{
|
||
drop_through_label = gen_label_rtx ();
|
||
do_jump (TREE_OPERAND (exp, 0), NULL_RTX, drop_through_label);
|
||
do_jump (TREE_OPERAND (exp, 1), if_false_label, NULL_RTX);
|
||
}
|
||
else
|
||
{
|
||
do_jump (TREE_OPERAND (exp, 0), NULL_RTX, if_true_label);
|
||
do_jump (TREE_OPERAND (exp, 1), if_false_label, if_true_label);
|
||
}
|
||
break;
|
||
|
||
/* Special case:
|
||
__builtin_expect (<test>, 0) and
|
||
__builtin_expect (<test>, 1)
|
||
|
||
We need to do this here, so that <test> is not converted to a SCC
|
||
operation on machines that use condition code registers and COMPARE
|
||
like the PowerPC, and then the jump is done based on whether the SCC
|
||
operation produced a 1 or 0. */
|
||
case CALL_EXPR:
|
||
/* Check for a built-in function. */
|
||
{
|
||
tree fndecl = get_callee_fndecl (exp);
|
||
tree arglist = TREE_OPERAND (exp, 1);
|
||
|
||
if (fndecl
|
||
&& DECL_BUILT_IN_CLASS (fndecl) == BUILT_IN_NORMAL
|
||
&& DECL_FUNCTION_CODE (fndecl) == BUILT_IN_EXPECT
|
||
&& arglist != NULL_TREE
|
||
&& TREE_CHAIN (arglist) != NULL_TREE)
|
||
{
|
||
rtx seq = expand_builtin_expect_jump (exp, if_false_label,
|
||
if_true_label);
|
||
|
||
if (seq != NULL_RTX)
|
||
{
|
||
emit_insn (seq);
|
||
return;
|
||
}
|
||
}
|
||
}
|
||
|
||
/* Fall through and generate the normal code. */
|
||
default:
|
||
normal:
|
||
temp = expand_normal (exp);
|
||
do_pending_stack_adjust ();
|
||
/* The RTL optimizers prefer comparisons against pseudos. */
|
||
if (GET_CODE (temp) == SUBREG)
|
||
{
|
||
/* Compare promoted variables in their promoted mode. */
|
||
if (SUBREG_PROMOTED_VAR_P (temp)
|
||
&& REG_P (XEXP (temp, 0)))
|
||
temp = XEXP (temp, 0);
|
||
else
|
||
temp = copy_to_reg (temp);
|
||
}
|
||
do_compare_rtx_and_jump (temp, CONST0_RTX (GET_MODE (temp)),
|
||
NE, TYPE_UNSIGNED (TREE_TYPE (exp)),
|
||
GET_MODE (temp), NULL_RTX,
|
||
if_false_label, if_true_label);
|
||
}
|
||
|
||
if (drop_through_label)
|
||
{
|
||
do_pending_stack_adjust ();
|
||
emit_label (drop_through_label);
|
||
}
|
||
}
|
||
|
||
/* Compare OP0 with OP1, word at a time, in mode MODE.
|
||
UNSIGNEDP says to do unsigned comparison.
|
||
Jump to IF_TRUE_LABEL if OP0 is greater, IF_FALSE_LABEL otherwise. */
|
||
|
||
static void
|
||
do_jump_by_parts_greater_rtx (enum machine_mode mode, int unsignedp, rtx op0,
|
||
rtx op1, rtx if_false_label, rtx if_true_label)
|
||
{
|
||
int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD);
|
||
rtx drop_through_label = 0;
|
||
int i;
|
||
|
||
if (! if_true_label || ! if_false_label)
|
||
drop_through_label = gen_label_rtx ();
|
||
if (! if_true_label)
|
||
if_true_label = drop_through_label;
|
||
if (! if_false_label)
|
||
if_false_label = drop_through_label;
|
||
|
||
/* Compare a word at a time, high order first. */
|
||
for (i = 0; i < nwords; i++)
|
||
{
|
||
rtx op0_word, op1_word;
|
||
|
||
if (WORDS_BIG_ENDIAN)
|
||
{
|
||
op0_word = operand_subword_force (op0, i, mode);
|
||
op1_word = operand_subword_force (op1, i, mode);
|
||
}
|
||
else
|
||
{
|
||
op0_word = operand_subword_force (op0, nwords - 1 - i, mode);
|
||
op1_word = operand_subword_force (op1, nwords - 1 - i, mode);
|
||
}
|
||
|
||
/* All but high-order word must be compared as unsigned. */
|
||
do_compare_rtx_and_jump (op0_word, op1_word, GT,
|
||
(unsignedp || i > 0), word_mode, NULL_RTX,
|
||
NULL_RTX, if_true_label);
|
||
|
||
/* Consider lower words only if these are equal. */
|
||
do_compare_rtx_and_jump (op0_word, op1_word, NE, unsignedp, word_mode,
|
||
NULL_RTX, NULL_RTX, if_false_label);
|
||
}
|
||
|
||
if (if_false_label)
|
||
emit_jump (if_false_label);
|
||
if (drop_through_label)
|
||
emit_label (drop_through_label);
|
||
}
|
||
|
||
/* Given a comparison expression EXP for values too wide to be compared
|
||
with one insn, test the comparison and jump to the appropriate label.
|
||
The code of EXP is ignored; we always test GT if SWAP is 0,
|
||
and LT if SWAP is 1. */
|
||
|
||
static void
|
||
do_jump_by_parts_greater (tree exp, int swap, rtx if_false_label,
|
||
rtx if_true_label)
|
||
{
|
||
rtx op0 = expand_normal (TREE_OPERAND (exp, swap));
|
||
rtx op1 = expand_normal (TREE_OPERAND (exp, !swap));
|
||
enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
int unsignedp = TYPE_UNSIGNED (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
|
||
do_jump_by_parts_greater_rtx (mode, unsignedp, op0, op1, if_false_label,
|
||
if_true_label);
|
||
}
|
||
|
||
/* Jump according to whether OP0 is 0. We assume that OP0 has an integer
|
||
mode, MODE, that is too wide for the available compare insns. Either
|
||
Either (but not both) of IF_TRUE_LABEL and IF_FALSE_LABEL may be NULL_RTX
|
||
to indicate drop through. */
|
||
|
||
static void
|
||
do_jump_by_parts_zero_rtx (enum machine_mode mode, rtx op0,
|
||
rtx if_false_label, rtx if_true_label)
|
||
{
|
||
int nwords = GET_MODE_SIZE (mode) / UNITS_PER_WORD;
|
||
rtx part;
|
||
int i;
|
||
rtx drop_through_label = 0;
|
||
|
||
/* The fastest way of doing this comparison on almost any machine is to
|
||
"or" all the words and compare the result. If all have to be loaded
|
||
from memory and this is a very wide item, it's possible this may
|
||
be slower, but that's highly unlikely. */
|
||
|
||
part = gen_reg_rtx (word_mode);
|
||
emit_move_insn (part, operand_subword_force (op0, 0, GET_MODE (op0)));
|
||
for (i = 1; i < nwords && part != 0; i++)
|
||
part = expand_binop (word_mode, ior_optab, part,
|
||
operand_subword_force (op0, i, GET_MODE (op0)),
|
||
part, 1, OPTAB_WIDEN);
|
||
|
||
if (part != 0)
|
||
{
|
||
do_compare_rtx_and_jump (part, const0_rtx, EQ, 1, word_mode,
|
||
NULL_RTX, if_false_label, if_true_label);
|
||
|
||
return;
|
||
}
|
||
|
||
/* If we couldn't do the "or" simply, do this with a series of compares. */
|
||
if (! if_false_label)
|
||
drop_through_label = if_false_label = gen_label_rtx ();
|
||
|
||
for (i = 0; i < nwords; i++)
|
||
do_compare_rtx_and_jump (operand_subword_force (op0, i, GET_MODE (op0)),
|
||
const0_rtx, EQ, 1, word_mode, NULL_RTX,
|
||
if_false_label, NULL_RTX);
|
||
|
||
if (if_true_label)
|
||
emit_jump (if_true_label);
|
||
|
||
if (drop_through_label)
|
||
emit_label (drop_through_label);
|
||
}
|
||
|
||
/* Test for the equality of two RTX expressions OP0 and OP1 in mode MODE,
|
||
where MODE is an integer mode too wide to be compared with one insn.
|
||
Either (but not both) of IF_TRUE_LABEL and IF_FALSE_LABEL may be NULL_RTX
|
||
to indicate drop through. */
|
||
|
||
static void
|
||
do_jump_by_parts_equality_rtx (enum machine_mode mode, rtx op0, rtx op1,
|
||
rtx if_false_label, rtx if_true_label)
|
||
{
|
||
int nwords = (GET_MODE_SIZE (mode) / UNITS_PER_WORD);
|
||
rtx drop_through_label = 0;
|
||
int i;
|
||
|
||
if (op1 == const0_rtx)
|
||
{
|
||
do_jump_by_parts_zero_rtx (mode, op0, if_false_label, if_true_label);
|
||
return;
|
||
}
|
||
else if (op0 == const0_rtx)
|
||
{
|
||
do_jump_by_parts_zero_rtx (mode, op1, if_false_label, if_true_label);
|
||
return;
|
||
}
|
||
|
||
if (! if_false_label)
|
||
drop_through_label = if_false_label = gen_label_rtx ();
|
||
|
||
for (i = 0; i < nwords; i++)
|
||
do_compare_rtx_and_jump (operand_subword_force (op0, i, mode),
|
||
operand_subword_force (op1, i, mode),
|
||
EQ, 0, word_mode, NULL_RTX,
|
||
if_false_label, NULL_RTX);
|
||
|
||
if (if_true_label)
|
||
emit_jump (if_true_label);
|
||
if (drop_through_label)
|
||
emit_label (drop_through_label);
|
||
}
|
||
|
||
/* Given an EQ_EXPR expression EXP for values too wide to be compared
|
||
with one insn, test the comparison and jump to the appropriate label. */
|
||
|
||
static void
|
||
do_jump_by_parts_equality (tree exp, rtx if_false_label, rtx if_true_label)
|
||
{
|
||
rtx op0 = expand_normal (TREE_OPERAND (exp, 0));
|
||
rtx op1 = expand_normal (TREE_OPERAND (exp, 1));
|
||
enum machine_mode mode = TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp, 0)));
|
||
do_jump_by_parts_equality_rtx (mode, op0, op1, if_false_label,
|
||
if_true_label);
|
||
}
|
||
|
||
/* Generate code for a comparison of OP0 and OP1 with rtx code CODE.
|
||
MODE is the machine mode of the comparison, not of the result.
|
||
(including code to compute the values to be compared) and set CC0
|
||
according to the result. The decision as to signed or unsigned
|
||
comparison must be made by the caller.
|
||
|
||
We force a stack adjustment unless there are currently
|
||
things pushed on the stack that aren't yet used.
|
||
|
||
If MODE is BLKmode, SIZE is an RTX giving the size of the objects being
|
||
compared. */
|
||
|
||
rtx
|
||
compare_from_rtx (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
|
||
enum machine_mode mode, rtx size)
|
||
{
|
||
rtx tem;
|
||
|
||
/* If one operand is constant, make it the second one. Only do this
|
||
if the other operand is not constant as well. */
|
||
|
||
if (swap_commutative_operands_p (op0, op1))
|
||
{
|
||
tem = op0;
|
||
op0 = op1;
|
||
op1 = tem;
|
||
code = swap_condition (code);
|
||
}
|
||
|
||
do_pending_stack_adjust ();
|
||
|
||
code = unsignedp ? unsigned_condition (code) : code;
|
||
tem = simplify_relational_operation (code, VOIDmode, mode, op0, op1);
|
||
if (tem)
|
||
{
|
||
if (CONSTANT_P (tem))
|
||
return tem;
|
||
|
||
if (COMPARISON_P (tem))
|
||
{
|
||
code = GET_CODE (tem);
|
||
op0 = XEXP (tem, 0);
|
||
op1 = XEXP (tem, 1);
|
||
mode = GET_MODE (op0);
|
||
unsignedp = (code == GTU || code == LTU
|
||
|| code == GEU || code == LEU);
|
||
}
|
||
}
|
||
|
||
emit_cmp_insn (op0, op1, code, size, mode, unsignedp);
|
||
|
||
#if HAVE_cc0
|
||
return gen_rtx_fmt_ee (code, VOIDmode, cc0_rtx, const0_rtx);
|
||
#else
|
||
return gen_rtx_fmt_ee (code, VOIDmode, op0, op1);
|
||
#endif
|
||
}
|
||
|
||
/* Like do_compare_and_jump but expects the values to compare as two rtx's.
|
||
The decision as to signed or unsigned comparison must be made by the caller.
|
||
|
||
If MODE is BLKmode, SIZE is an RTX giving the size of the objects being
|
||
compared. */
|
||
|
||
void
|
||
do_compare_rtx_and_jump (rtx op0, rtx op1, enum rtx_code code, int unsignedp,
|
||
enum machine_mode mode, rtx size, rtx if_false_label,
|
||
rtx if_true_label)
|
||
{
|
||
rtx tem;
|
||
int dummy_true_label = 0;
|
||
|
||
/* Reverse the comparison if that is safe and we want to jump if it is
|
||
false. */
|
||
if (! if_true_label && ! FLOAT_MODE_P (mode))
|
||
{
|
||
if_true_label = if_false_label;
|
||
if_false_label = 0;
|
||
code = reverse_condition (code);
|
||
}
|
||
|
||
/* If one operand is constant, make it the second one. Only do this
|
||
if the other operand is not constant as well. */
|
||
|
||
if (swap_commutative_operands_p (op0, op1))
|
||
{
|
||
tem = op0;
|
||
op0 = op1;
|
||
op1 = tem;
|
||
code = swap_condition (code);
|
||
}
|
||
|
||
do_pending_stack_adjust ();
|
||
|
||
code = unsignedp ? unsigned_condition (code) : code;
|
||
if (0 != (tem = simplify_relational_operation (code, mode, VOIDmode,
|
||
op0, op1)))
|
||
{
|
||
if (CONSTANT_P (tem))
|
||
{
|
||
rtx label = (tem == const0_rtx || tem == CONST0_RTX (mode))
|
||
? if_false_label : if_true_label;
|
||
if (label)
|
||
emit_jump (label);
|
||
return;
|
||
}
|
||
|
||
code = GET_CODE (tem);
|
||
mode = GET_MODE (tem);
|
||
op0 = XEXP (tem, 0);
|
||
op1 = XEXP (tem, 1);
|
||
unsignedp = (code == GTU || code == LTU || code == GEU || code == LEU);
|
||
}
|
||
|
||
|
||
if (! if_true_label)
|
||
{
|
||
dummy_true_label = 1;
|
||
if_true_label = gen_label_rtx ();
|
||
}
|
||
|
||
if (GET_MODE_CLASS (mode) == MODE_INT
|
||
&& ! can_compare_p (code, mode, ccp_jump))
|
||
{
|
||
switch (code)
|
||
{
|
||
case LTU:
|
||
do_jump_by_parts_greater_rtx (mode, 1, op1, op0,
|
||
if_false_label, if_true_label);
|
||
break;
|
||
|
||
case LEU:
|
||
do_jump_by_parts_greater_rtx (mode, 1, op0, op1,
|
||
if_true_label, if_false_label);
|
||
break;
|
||
|
||
case GTU:
|
||
do_jump_by_parts_greater_rtx (mode, 1, op0, op1,
|
||
if_false_label, if_true_label);
|
||
break;
|
||
|
||
case GEU:
|
||
do_jump_by_parts_greater_rtx (mode, 1, op1, op0,
|
||
if_true_label, if_false_label);
|
||
break;
|
||
|
||
case LT:
|
||
do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
|
||
if_false_label, if_true_label);
|
||
break;
|
||
|
||
case LE:
|
||
do_jump_by_parts_greater_rtx (mode, 0, op0, op1,
|
||
if_true_label, if_false_label);
|
||
break;
|
||
|
||
case GT:
|
||
do_jump_by_parts_greater_rtx (mode, 0, op0, op1,
|
||
if_false_label, if_true_label);
|
||
break;
|
||
|
||
case GE:
|
||
do_jump_by_parts_greater_rtx (mode, 0, op1, op0,
|
||
if_true_label, if_false_label);
|
||
break;
|
||
|
||
case EQ:
|
||
do_jump_by_parts_equality_rtx (mode, op0, op1, if_false_label,
|
||
if_true_label);
|
||
break;
|
||
|
||
case NE:
|
||
do_jump_by_parts_equality_rtx (mode, op0, op1, if_true_label,
|
||
if_false_label);
|
||
break;
|
||
|
||
default:
|
||
gcc_unreachable ();
|
||
}
|
||
}
|
||
else
|
||
emit_cmp_and_jump_insns (op0, op1, code, size, mode, unsignedp,
|
||
if_true_label);
|
||
|
||
if (if_false_label)
|
||
emit_jump (if_false_label);
|
||
if (dummy_true_label)
|
||
emit_label (if_true_label);
|
||
}
|
||
|
||
/* Generate code for a comparison expression EXP (including code to compute
|
||
the values to be compared) and a conditional jump to IF_FALSE_LABEL and/or
|
||
IF_TRUE_LABEL. One of the labels can be NULL_RTX, in which case the
|
||
generated code will drop through.
|
||
SIGNED_CODE should be the rtx operation for this comparison for
|
||
signed data; UNSIGNED_CODE, likewise for use if data is unsigned.
|
||
|
||
We force a stack adjustment unless there are currently
|
||
things pushed on the stack that aren't yet used. */
|
||
|
||
static void
|
||
do_compare_and_jump (tree exp, enum rtx_code signed_code,
|
||
enum rtx_code unsigned_code, rtx if_false_label,
|
||
rtx if_true_label)
|
||
{
|
||
rtx op0, op1;
|
||
tree type;
|
||
enum machine_mode mode;
|
||
int unsignedp;
|
||
enum rtx_code code;
|
||
|
||
/* Don't crash if the comparison was erroneous. */
|
||
op0 = expand_normal (TREE_OPERAND (exp, 0));
|
||
if (TREE_CODE (TREE_OPERAND (exp, 0)) == ERROR_MARK)
|
||
return;
|
||
|
||
op1 = expand_normal (TREE_OPERAND (exp, 1));
|
||
if (TREE_CODE (TREE_OPERAND (exp, 1)) == ERROR_MARK)
|
||
return;
|
||
|
||
type = TREE_TYPE (TREE_OPERAND (exp, 0));
|
||
mode = TYPE_MODE (type);
|
||
if (TREE_CODE (TREE_OPERAND (exp, 0)) == INTEGER_CST
|
||
&& (TREE_CODE (TREE_OPERAND (exp, 1)) != INTEGER_CST
|
||
|| (GET_MODE_BITSIZE (mode)
|
||
> GET_MODE_BITSIZE (TYPE_MODE (TREE_TYPE (TREE_OPERAND (exp,
|
||
1)))))))
|
||
{
|
||
/* op0 might have been replaced by promoted constant, in which
|
||
case the type of second argument should be used. */
|
||
type = TREE_TYPE (TREE_OPERAND (exp, 1));
|
||
mode = TYPE_MODE (type);
|
||
}
|
||
unsignedp = TYPE_UNSIGNED (type);
|
||
code = unsignedp ? unsigned_code : signed_code;
|
||
|
||
#ifdef HAVE_canonicalize_funcptr_for_compare
|
||
/* If function pointers need to be "canonicalized" before they can
|
||
be reliably compared, then canonicalize them.
|
||
Only do this if *both* sides of the comparison are function pointers.
|
||
If one side isn't, we want a noncanonicalized comparison. See PR
|
||
middle-end/17564. */
|
||
if (HAVE_canonicalize_funcptr_for_compare
|
||
&& TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 0))) == POINTER_TYPE
|
||
&& TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 0))))
|
||
== FUNCTION_TYPE
|
||
&& TREE_CODE (TREE_TYPE (TREE_OPERAND (exp, 1))) == POINTER_TYPE
|
||
&& TREE_CODE (TREE_TYPE (TREE_TYPE (TREE_OPERAND (exp, 1))))
|
||
== FUNCTION_TYPE)
|
||
{
|
||
rtx new_op0 = gen_reg_rtx (mode);
|
||
rtx new_op1 = gen_reg_rtx (mode);
|
||
|
||
emit_insn (gen_canonicalize_funcptr_for_compare (new_op0, op0));
|
||
op0 = new_op0;
|
||
|
||
emit_insn (gen_canonicalize_funcptr_for_compare (new_op1, op1));
|
||
op1 = new_op1;
|
||
}
|
||
#endif
|
||
|
||
do_compare_rtx_and_jump (op0, op1, code, unsignedp, mode,
|
||
((mode == BLKmode)
|
||
? expr_size (TREE_OPERAND (exp, 0)) : NULL_RTX),
|
||
if_false_label, if_true_label);
|
||
}
|
||
|
||
#include "gt-dojump.h"
|