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re PR middle-end/18045 (signed integer remainder for power of 2 broken)

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PR middle-end/18045
	* expmed.c (expand_smod_pow2): Handle modes whose size
	is greater than that of HOST_WIDE_INT.

From-SVN: r89253
This commit is contained in:
Eric Botcazou 2004-10-19 00:45:01 +02:00 committed by Eric Botcazou
parent d4de696663
commit 6e7a355c16
4 changed files with 57 additions and 12 deletions
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6
gcc/ChangeLog
View File

@ -1,3 +1,9 @@
2004-10-18 Eric Botcazou <ebotcazou@libertysurf.fr>
PR middle-end/18045
* expmed.c (expand_smod_pow2): Handle modes whose size
is greater than that of HOST_WIDE_INT.
2004-10-18 Ziemowit Laski <zlaski@apple.com>
* c-parse.in (reservedwords): Add OBJC_TYPE_QUAL as alternative.

34
gcc/expmed.c
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@ -3193,7 +3193,7 @@ expand_mult_highpart (enum machine_mode mode, rtx op0,
static rtx
expand_smod_pow2 (enum machine_mode mode, rtx op0, HOST_WIDE_INT d)
{
unsigned HOST_WIDE_INT mask;
unsigned HOST_WIDE_INT masklow, maskhigh;
rtx result, temp, shift, label;
int logd;
@ -3209,14 +3209,14 @@ expand_smod_pow2 (enum machine_mode mode, rtx op0, HOST_WIDE_INT d)
if (signmask)
{
signmask = force_reg (mode, signmask);
mask = ((HOST_WIDE_INT) 1 << logd) - 1;
masklow = ((HOST_WIDE_INT) 1 << logd) - 1;
shift = GEN_INT (GET_MODE_BITSIZE (mode) - logd);
/* Use the rtx_cost of a LSHIFTRT instruction to determine
which instruction sequence to use. If logical right shifts
are expensive the use 2 XORs, 2 SUBs and an AND, otherwise
use a LSHIFTRT, 1 ADD, 1 SUB and an AND. */
temp = gen_rtx_LSHIFTRT (mode, result, shift);
if (lshr_optab->handlers[mode].insn_code == CODE_FOR_nothing
|| rtx_cost (temp, SET) > COSTS_N_INSNS (2))
@ -3225,7 +3225,7 @@ expand_smod_pow2 (enum machine_mode mode, rtx op0, HOST_WIDE_INT d)
NULL_RTX, 1, OPTAB_LIB_WIDEN);
temp = expand_binop (mode, sub_optab, temp, signmask,
NULL_RTX, 1, OPTAB_LIB_WIDEN);
temp = expand_binop (mode, and_optab, temp, GEN_INT (mask),
temp = expand_binop (mode, and_optab, temp, GEN_INT (masklow),
NULL_RTX, 1, OPTAB_LIB_WIDEN);
temp = expand_binop (mode, xor_optab, temp, signmask,
NULL_RTX, 1, OPTAB_LIB_WIDEN);
@ -3240,7 +3240,7 @@ expand_smod_pow2 (enum machine_mode mode, rtx op0, HOST_WIDE_INT d)
temp = expand_binop (mode, add_optab, op0, signmask,
NULL_RTX, 1, OPTAB_LIB_WIDEN);
temp = expand_binop (mode, and_optab, temp, GEN_INT (mask),
temp = expand_binop (mode, and_optab, temp, GEN_INT (masklow),
NULL_RTX, 1, OPTAB_LIB_WIDEN);
temp = expand_binop (mode, sub_optab, temp, signmask,
NULL_RTX, 1, OPTAB_LIB_WIDEN);
@ -3254,11 +3254,19 @@ expand_smod_pow2 (enum machine_mode mode, rtx op0, HOST_WIDE_INT d)
can avoid an explicit compare operation in the following comparison
against zero. */
mask = (HOST_WIDE_INT) -1 << (GET_MODE_BITSIZE (mode) - 1)
| (((HOST_WIDE_INT) 1 << logd) - 1);
masklow = ((HOST_WIDE_INT) 1 << logd) - 1;
if (GET_MODE_BITSIZE (mode) <= HOST_BITS_PER_WIDE_INT)
{
masklow |= (HOST_WIDE_INT) -1 << (GET_MODE_BITSIZE (mode) - 1);
maskhigh = -1;
}
else
maskhigh = (HOST_WIDE_INT) -1
<< (GET_MODE_BITSIZE (mode) - HOST_BITS_PER_WIDE_INT - 1);
temp = expand_binop (mode, and_optab, op0, GEN_INT (mask), result,
1, OPTAB_LIB_WIDEN);
temp = expand_binop (mode, and_optab, op0,
immed_double_const (masklow, maskhigh, mode),
result, 1, OPTAB_LIB_WIDEN);
if (temp != result)
emit_move_insn (result, temp);
@ -3267,9 +3275,11 @@ expand_smod_pow2 (enum machine_mode mode, rtx op0, HOST_WIDE_INT d)
temp = expand_binop (mode, sub_optab, result, const1_rtx, result,
0, OPTAB_LIB_WIDEN);
mask = (HOST_WIDE_INT) -1 << logd;
temp = expand_binop (mode, ior_optab, temp, GEN_INT (mask), result,
1, OPTAB_LIB_WIDEN);
masklow = (HOST_WIDE_INT) -1 << logd;
maskhigh = -1;
temp = expand_binop (mode, ior_optab, temp,
immed_double_const (masklow, maskhigh, mode),
result, 1, OPTAB_LIB_WIDEN);
temp = expand_binop (mode, add_optab, temp, const1_rtx, result,
0, OPTAB_LIB_WIDEN);
if (temp != result)

4
gcc/testsuite/ChangeLog
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@ -1,3 +1,7 @@
2004-10-18 Eric Botcazou <ebotcazou@libertysurf.fr>
* gcc.dg/smod-1.c: New test.
2004-10-18 Ziemowit Laski <zlaski@apple.com>
* objc.dg/method-14.m: New test.

25
gcc/testsuite/gcc.dg/smod-1.c Normal file
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@ -0,0 +1,25 @@
/* PR middle-end/18045 */
/* Contributed by Eric Botcazou <ebotcazou@libertysurf.fr> */
/* { dg-do run } */
/* { dg-options "-std=c99" } */
/* { dg-options "-std=c99 -mtune=i486" { target i?86-*-* x86_64-*-* } } */
#include <limits.h>
extern void abort(void);
long long smod16(long long x)
{
return x % 16;
}
int main(void)
{
#if LLONG_MAX > 2147483647L
if (smod16 (0xFFFFFFFF) != 0xF)
abort ();
#endif
return 0;
}