Update copyright dates with scripts/update-copyrights.

[thirdparty/glibc.git] / sysdeps / i386 / fpu / s_expm1f.S

diff --git a/sysdeps/i386/fpu/s_expm1f.S b/sysdeps/i386/fpu/s_expm1f.S
index 8645107274d90bc52282bcc20b1cba8d0f087c8e..424b5322794fe7d32db1c0641e52fecc31028052 100644 (file)
--- a/sysdeps/i386/fpu/s_expm1f.S
+++ b/sysdeps/i386/fpu/s_expm1f.S
@@ -1,5 +1,5 @@
 /* ix87 specific implementation of exp(x)-1.
-   Copyright (C) 1996, 1997, 2005 Free Software Foundation, Inc.
+   Copyright (C) 1996-2019 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
    Contributed by Ulrich Drepper <drepper@cygnus.com>, 1996.
    Based on code by John C. Bowman <bowman@ipp-garching.mpg.de>.
@@ -16,31 +16,31 @@
    Lesser General Public License for more details.
 
    You should have received a copy of the GNU Lesser General Public
-   License along with the GNU C Library; if not, write to the Free
-   Software Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA
-   02111-1307 USA.  */
+   License along with the GNU C Library; if not, see
+   <http://www.gnu.org/licenses/>.  */
 
        /* Using: e^x - 1 = 2^(x * log2(e)) - 1 */
 
 #include <sysdep.h>
 #include <machine/asm.h>
+#include <i386-math-asm.h>
+#include <libm-alias-float.h>
 
-#ifdef __ELF__
        .section .rodata
-#else
-       .text
-#endif
+
        .align ALIGNARG(4)
-       ASM_TYPE_DIRECTIVE(minus1,@object)
+       .type minus1,@object
 minus1:        .double -1.0
        ASM_SIZE_DIRECTIVE(minus1)
-       ASM_TYPE_DIRECTIVE(one,@object)
+       .type one,@object
 one:   .double 1.0
        ASM_SIZE_DIRECTIVE(one)
-       ASM_TYPE_DIRECTIVE(l2e,@object)
+       .type l2e,@object
 l2e:   .tfloat 1.442695040888963407359924681002
        ASM_SIZE_DIRECTIVE(l2e)
 
+DEFINE_FLT_MIN
+
 #ifdef PIC
 #define MO(op) op##@GOTOFF(%edx)
 #else
@@ -55,22 +55,45 @@ ENTRY(__expm1f)
        jae     HIDDEN_JUMPTARGET (__expf)
 
        flds    4(%esp)         // x
-       fxam                    // Is NaN or +-Inf?
+       fxam                    // Is NaN, +-Inf or +-0?
+       xorb    $0x80, %ah
+       cmpl    $0xc190, %eax   // is num <= -18.0?
        fstsw   %ax
        movb    $0x45, %ch
+       jb      4f
+
+       // Below -18.0 (may be -NaN or -Inf).
+       andb    %ah, %ch
+#ifdef PIC
+       LOAD_PIC_REG (dx)
+#endif
+       cmpb    $0x01, %ch
+       je      5f              // If -NaN, jump.
+       jmp     2f              // -large, possibly -Inf.
+
+4:     // In range -18.0 to 88.5 (may be +-0 but not NaN or +-Inf).
        andb    %ah, %ch
        cmpb    $0x40, %ch
        je      3f              // If +-0, jump.
 #ifdef PIC
        LOAD_PIC_REG (dx)
 #endif
-       cmpb    $0x05, %ch
-       je      2f              // If +-Inf, jump.
 
-       fldt    MO(l2e)         // log2(e) : x
+5:     fldt    MO(l2e)         // log2(e) : x
        fmulp                   // log2(e)*x
        fld     %st             // log2(e)*x : log2(e)*x
+       // Set round-to-nearest temporarily.
+       subl    $8, %esp
+       cfi_adjust_cfa_offset (8)
+       fstcw   4(%esp)
+       movl    $0xf3ff, %ecx
+       andl    4(%esp), %ecx
+       movl    %ecx, (%esp)
+       fldcw   (%esp)
        frndint                 // int(log2(e)*x) : log2(e)*x
+       fldcw   4(%esp)
+       addl    $8, %esp
+       cfi_adjust_cfa_offset (-8)
        fsubr   %st, %st(1)     // int(log2(e)*x) : fract(log2(e)*x)
        fxch                    // fract(log2(e)*x) : int(log2(e)*x)
        f2xm1                   // 2^fract(log2(e)*x)-1 : int(log2(e)*x)
@@ -81,12 +104,11 @@ ENTRY(__expm1f)
        fsubrl  MO(one)         // 1-2^int(log2(e)*x) : int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
        fstp    %st(1)          // 1-2^int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
        fsubrp  %st, %st(1)     // 2^(log2(e)*x)
+       FLT_CHECK_FORCE_UFLOW
        ret
 
-2:     testl   $0x200, %eax    // Test sign.
-       jz      3f              // If positive, jump.
-       fstp    %st
+2:     fstp    %st
        fldl    MO(minus1)      // Set result to -1.0.
 3:     ret
 END(__expm1f)
-weak_alias (__expm1f, expm1f)
+libm_alias_float (__expm1, expm1)