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PowerPC floating point little-endian [9 of 15]

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http://sourceware.org/ml/libc-alpha/2013-07/msg00200.html

This works around the fact that vsx is disabled in current
little-endian gcc.  Also, float constants take 4 bytes in memory
vs. 16 bytes for vector constants, and we don't need to write one lot
of masks for double (register format) and another for float (mem
format).

	* sysdeps/powerpc/fpu/s_float_bitwise.h (__float_and_test28): Don't
	use vector int constants.
	(__float_and_test24, __float_and8, __float_get_exp): Likewise.
This commit is contained in:
Alan Modra 2013-08-17 18:29:43 +09:30
parent 4a28b3ca4b
commit 603e84104c
2 changed files with 35 additions and 25 deletions
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6
ChangeLog
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@ -1,3 +1,9 @@
2013-10-04 Alan Modra <amodra@gmail.com>
* sysdeps/powerpc/fpu/s_float_bitwise.h (__float_and_test28): Don't
use vector int constants.
(__float_and_test24, __float_and8, __float_get_exp): Likewise.
2013-10-04 Anton Blanchard <anton@au1.ibm.com>
* sysdeps/powerpc/fpu/fenv_libc.h (fenv_union_t): Replace int

54
sysdeps/powerpc/fpu/s_float_bitwise.h
View File

@ -23,18 +23,19 @@
#include <math_private.h>
/* Returns (int)(num & 0x7FFFFFF0 == value) */
static inline
int __float_and_test28 (float num, float value)
static inline int
__float_and_test28 (float num, float value)
{
float ret;
#ifdef _ARCH_PWR7
vector int mask = (vector int) {
0x7ffffffe, 0x00000000, 0x00000000, 0x0000000
};
union {
int i;
float f;
} mask = { .i = 0x7ffffff0 };
__asm__ (
/* the 'f' constrain is use on mask because we just need
/* the 'f' constraint is used on mask because we just need
* to compare floats, not full vector */
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask)
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask.f)
);
#else
int32_t inum;
@ -46,16 +47,17 @@ int __float_and_test28 (float num, float value)
}
/* Returns (int)(num & 0x7FFFFF00 == value) */
static inline
int __float_and_test24 (float num, float value)
static inline int
__float_and_test24 (float num, float value)
{
float ret;
#ifdef _ARCH_PWR7
vector int mask = (vector int) {
0x7fffffe0, 0x00000000, 0x00000000, 0x0000000
};
union {
int i;
float f;
} mask = { .i = 0x7fffff00 };
__asm__ (
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask)
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask.f)
);
#else
int32_t inum;
@ -67,16 +69,17 @@ int __float_and_test24 (float num, float value)
}
/* Returns (float)(num & 0x7F800000) */
static inline
float __float_and8 (float num)
static inline float
__float_and8 (float num)
{
float ret;
#ifdef _ARCH_PWR7
vector int mask = (vector int) {
0x7ff00000, 0x00000000, 0x00000000, 0x00000000
};
union {
int i;
float f;
} mask = { .i = 0x7f800000 };
__asm__ (
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask)
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask.f)
);
#else
int32_t inum;
@ -88,17 +91,18 @@ float __float_and8 (float num)
}
/* Returns ((int32_t)(num & 0x7F800000) >> 23) */
static inline
int32_t __float_get_exp (float num)
static inline int32_t
__float_get_exp (float num)
{
int32_t inum;
#ifdef _ARCH_PWR7
float ret;
vector int mask = (vector int) {
0x7ff00000, 0x00000000, 0x00000000, 0x00000000
};
union {
int i;
float f;
} mask = { .i = 0x7f800000 };
__asm__ (
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask)
"xxland %x0,%x1,%x2" : "=f" (ret) : "f" (num), "f" (mask.f)
);
GET_FLOAT_WORD(inum, ret);
#else