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PowerPC floating point little-endian [9 of 15]
- From: Alan Modra <amodra at gmail dot com>
- To: libc-alpha at sourceware dot org
- Date: Wed, 10 Jul 2013 10:59:33 +0930
- Subject: PowerPC floating point little-endian [9 of 15]
- References: <20130710012435 dot GN2602 at bubble dot grove dot modra dot org>
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).
2013-07-10 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.
diff --git a/sysdeps/powerpc/fpu/s_float_bitwise.h b/sysdeps/powerpc/fpu/s_float_bitwise.h
index 8e4adca..c0a4e56 100644
--- a/sysdeps/powerpc/fpu/s_float_bitwise.h
+++ b/sysdeps/powerpc/fpu/s_float_bitwise.h
@@ -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
--
Alan Modra
Australia Development Lab, IBM