--- Begin Message ---
- To: Debian Bug Tracking System <submit@bugs.debian.org>
- Subject: Produces NEON code on armhf even when explicitly asked not to
- From: Steve McIntyre <steve@einval.com>
- Date: Tue, 24 Jan 2012 14:52:52 +0000
- Message-id: <20120124145252.1348.73107.reportbug@tack.local>
Package: gcc-4.6
Version: 4:4.6.2-12
Severity: important
Hi,
Looking at a FTBFS bug on armhf in the pytables package. gcc-4.6 seems
to be emitting NEON code even when explicitly told not to:
(sid)93sam@harris:~$ gcc -c typeconv.c -march=armv7-a -mfloat-abi=hard -mfpu=vfpv3-d16 -mthumb -o typeconv.o
(sid)93sam@harris:~$ objdump -D typeconv.o | grep vldr
a8: ed93 6b00 vldr d6, [r3]
ae: ed93 7b00 vldr d7, [r3]
be: ed9f 7b44 vldr d7, [pc, #272] ; 1d0 <conv_float64_timeval32+0x1d0>
118: ed9f 7b2f vldr d7, [pc, #188] ; 1d8 <conv_float64_timeval32+0x1d8>
There's other NEON code in the assembly output too, the grep is just
to show an example...
The single small source file is attached.
/***********************************************************************
*
* License: BSD
* Created: December 21, 2004
* Author: Ivan Vilata i Balaguer - reverse:net.selidor@ivan
* Modified:
* Function inlining and some castings for 64-bit adressing
* Francesc Alted 2004-12-27
*
* $Source: /cvsroot/pytables/pytables/src/typeconv.c,v $
* $Id$
*
***********************************************************************/
/* Type conversion functions for PyTables types which are stored
* with a different representation between numpy and HDF5.
*/
#define PY_LONG_LONG long long
#include <math.h>
#include <assert.h>
#if (!defined _ISOC99_SOURCE && !defined __USE_ISOC99)
long int lround(double x)
{
double trunx;
if (x > 0.0) {
trunx = floor(x);
if (x - trunx >= 0.5)
trunx += 1;
} else {
trunx = ceil(x);
if (trunx - x >= 0.5)
trunx -= 1;
}
return (long int)(trunx);
}
#endif /* !_ISOC99_SOURCE && !__USE_ISOC99 */
void conv_float64_timeval32(void *base,
unsigned long byteoffset,
unsigned long bytestride,
PY_LONG_LONG nrecords,
unsigned long nelements,
int sense)
{
PY_LONG_LONG record;
unsigned long element, gapsize;
double *fieldbase;
union {
PY_LONG_LONG i64;
double f64;
} tv;
assert(bytestride > 0);
assert(nelements > 0);
/* Byte distance from end of field to beginning of next field. */
gapsize = bytestride - nelements * sizeof(double);
fieldbase = (double *)((unsigned char *)(base) + byteoffset);
for (record = 0; record < nrecords; record++) {
for (element = 0; element < nelements; element++) {
if (sense == 0) {
/* Convert from float64 to timeval32. */
tv.i64 = (((PY_LONG_LONG)(*fieldbase) << 32)
| (lround((*fieldbase - (int)(*fieldbase)) * 1e+6)
& 0x0ffffffff));
*fieldbase = tv.f64;
} else {
/* Convert from timeval32 to float64. */
tv.f64 = *fieldbase;
/* the next computation is 64 bit-platforms aware */
*fieldbase = 1e-6 * (int)tv.i64 + (tv.i64 >> 32);
}
fieldbase++;
}
fieldbase = (double *)((unsigned char *)(fieldbase) + gapsize);
/* XXX: Need to check if this works on platforms which require
64-bit data to be aligned. ivb(2005-01-07) */
}
assert(fieldbase == (base + byteoffset + bytestride * nrecords));
}
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