math: Use expm1f from CORE-MATH

The CORE-MATH implementation is correctly rounded (for any rounding mode)
and shows better performance compared to the generic expm1f.

The code was adapted to glibc style and to use the definition of
math_config.h (to handle errno, overflow, and underflow).

Benchtest on x64_64 (Ryzen 9 5900X, gcc 14.2.1), aarch64 (Neoverse-N1,
gcc 13.3.1), and powerpc (POWER10, gcc 13.2.1):

Latency                      master        patched   improvement
x86_64                      96.7402        36.4026        62.37%
x86_64v2                    97.5391        33.4625        65.69%
x86_64v3                    82.1778        30.8668        62.44%
i686                         120.58        94.8302        21.35%
aarch64                     32.3558        12.8881        60.17%
power10                     23.5087        9.8574         58.07%
powerpc                     23.4776        9.06325        61.40%

reciprocal-throughput        master        patched   improvement
x86_64                      27.8224        15.9255        42.76%
x86_64v2                    27.8364        9.6438         65.36%
x86_64v3                    20.3227        9.6146         52.69%
i686                        63.5629        59.4718         6.44%
aarch64                     17.4838        7.1082         59.34%
power10                     12.4644        8.7829         29.54%
powerpc                     14.2152        5.94765        58.16%

Signed-off-by: Alexei Sibidanov <sibid@uvic.ca>
Signed-off-by: Paul Zimmermann <Paul.Zimmermann@inria.fr>
Signed-off-by: Adhemerval Zanella <adhemerval.zanella@linaro.org>
Reviewed-by: DJ Delorie <dj@redhat.com>

29 files changed, 123 insertions, 320 deletions

diff --git a/SHARED-FILES b/SHARED-FILES
index 0c85e2e..7b10d0e 100644
--- a/SHARED-FILES
+++ b/SHARED-FILES
@@ -248,3 +248,7 @@ sysdeps/ieee754/flt-32/s_exp2m1f.c
   (file src/binary32/exp2m1/exp2m1f.c in CORE-MATH)
   - The code was adapted to use glibc code style and internal
     functions to handle errno, overflow, and underflow.
+sysdeps/ieee754/flt-32/s_expm1f.c
+  (file src/binary32/expm1/expm1f.c in CORE-MATH)
+  - The code was adapted to use glibc code style and internal
+    functions to handle errno, overflow, and underflow.
diff --git a/sysdeps/aarch64/libm-test-ulps b/sysdeps/aarch64/libm-test-ulps
index 29ccd1d..c6c40df 100644
--- a/sysdeps/aarch64/libm-test-ulps
+++ b/sysdeps/aarch64/libm-test-ulps
@@ -801,6 +801,7 @@ float: 1
 ldouble: 1
 
 Function: Imaginary part of "csin":
+float: 1
 ldouble: 1
 
 Function: Real part of "csin_downward":
@@ -1163,7 +1164,6 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_advsimd":
@@ -1172,7 +1172,6 @@ float: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_sve":
@@ -1181,12 +1180,10 @@ float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/alpha/fpu/libm-test-ulps b/sysdeps/alpha/fpu/libm-test-ulps
index 5c61754..09185dd 100644
--- a/sysdeps/alpha/fpu/libm-test-ulps
+++ b/sysdeps/alpha/fpu/libm-test-ulps
@@ -1034,22 +1034,18 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/arc/fpu/libm-test-ulps b/sysdeps/arc/fpu/libm-test-ulps
index a5f9d50..bacaf51 100644
--- a/sysdeps/arc/fpu/libm-test-ulps
+++ b/sysdeps/arc/fpu/libm-test-ulps
@@ -839,19 +839,15 @@ float: 2
 
 Function: "expm1":
 double: 2
-float: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 2
-float: 2
 
 Function: "gamma":
 double: 7
diff --git a/sysdeps/arc/nofpu/libm-test-ulps b/sysdeps/arc/nofpu/libm-test-ulps
index 574ae8b..266381f 100644
--- a/sysdeps/arc/nofpu/libm-test-ulps
+++ b/sysdeps/arc/nofpu/libm-test-ulps
@@ -203,7 +203,6 @@ double: 2
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/arm/libm-test-ulps b/sysdeps/arm/libm-test-ulps
index 28718c7..12451d2 100644
--- a/sysdeps/arm/libm-test-ulps
+++ b/sysdeps/arm/libm-test-ulps
@@ -574,6 +574,9 @@ Function: Real part of "csin":
 double: 1
 float: 1
 
+Function: Imaginary part of "csin":
+float: 1
+
 Function: Real part of "csin_downward":
 double: 3
 float: 3
@@ -831,19 +834,15 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/csky/fpu/libm-test-ulps b/sysdeps/csky/fpu/libm-test-ulps
index 151df00..3f17778 100644
--- a/sysdeps/csky/fpu/libm-test-ulps
+++ b/sysdeps/csky/fpu/libm-test-ulps
@@ -799,19 +799,15 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/csky/nofpu/libm-test-ulps b/sysdeps/csky/nofpu/libm-test-ulps
index 48697a7..fdef935 100644
--- a/sysdeps/csky/nofpu/libm-test-ulps
+++ b/sysdeps/csky/nofpu/libm-test-ulps
@@ -797,19 +797,15 @@ double: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/hppa/fpu/libm-test-ulps b/sysdeps/hppa/fpu/libm-test-ulps
index 338ca77..05ad1cf 100644
--- a/sysdeps/hppa/fpu/libm-test-ulps
+++ b/sysdeps/hppa/fpu/libm-test-ulps
@@ -850,20 +850,16 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/i386/fpu/libm-test-ulps b/sysdeps/i386/fpu/libm-test-ulps
index 98a5a53..abf9a91 100644
--- a/sysdeps/i386/fpu/libm-test-ulps
+++ b/sysdeps/i386/fpu/libm-test-ulps
@@ -1234,19 +1234,16 @@ ldouble: 3
 
 Function: "expm1_downward":
 double: 1
-float: 1
 float128: 2
 ldouble: 4
 
 Function: "expm1_towardzero":
 double: 1
-float: 1
 float128: 4
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 float128: 3
 ldouble: 4
 
diff --git a/sysdeps/i386/fpu/s_expm1f.S b/sysdeps/i386/fpu/s_expm1f.S
deleted file mode 100644
index a1cb5bf..0000000
--- a/sysdeps/i386/fpu/s_expm1f.S
+++ /dev/null
@@ -1,112 +0,0 @@
-/* ix87 specific implementation of exp(x)-1.
-   Copyright (C) 1996-2024 Free Software Foundation, Inc.
-   This file is part of the GNU C Library.
-
-   The GNU C Library is free software; you can redistribute it and/or
-   modify it under the terms of the GNU Lesser General Public
-   License as published by the Free Software Foundation; either
-   version 2.1 of the License, or (at your option) any later version.
-
-   The GNU C Library is distributed in the hope that it will be useful,
-   but WITHOUT ANY WARRANTY; without even the implied warranty of
-   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
-   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, see
-   <https://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>
-
-	.section .rodata
-
-	.align ALIGNARG(4)
-	.type minus1,@object
-minus1:	.double -1.0
-	ASM_SIZE_DIRECTIVE(minus1)
-	.type one,@object
-one:	.double 1.0
-	ASM_SIZE_DIRECTIVE(one)
-	.type l2e,@object
-l2e:	.quad  0xb8aa3b295c17f0bc  /* 1.442695040888963407359924681002  */
-	.short 0x3fff
-	ASM_SIZE_DIRECTIVE(l2e)
-
-DEFINE_FLT_MIN
-
-#ifdef PIC
-#define MO(op) op##@GOTOFF(%edx)
-#else
-#define MO(op) op
-#endif
-
-	.text
-ENTRY(__expm1f)
-	movzwl	4+2(%esp), %eax
-	xorb	$0x80, %ah	// invert sign bit (now 1 is "positive")
-	cmpl	$0xc2b1, %eax	// is num >= 88.5?
-	jae	HIDDEN_JUMPTARGET (__expf)
-
-	flds	4(%esp)		// x
-	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
-
-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)
-	fscale			// 2^(log2(e)*x)-2^int(log2(e)*x) : int(log2(e)*x)
-	fxch			// int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
-	fldl	MO(one)		// 1 : int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
-	fscale			// 2^int(log2(e)*x) : int(log2(e)*x) : 2^(log2(e)*x)-2^int(log2(e)*x)
-	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:	fstp	%st
-	fldl	MO(minus1)	// Set result to -1.0.
-3:	ret
-END(__expm1f)
-libm_alias_float (__expm1, expm1)
diff --git a/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps b/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
index 9afb63b..6d9d49d 100644
--- a/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
+++ b/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
@@ -1237,19 +1237,16 @@ ldouble: 3
 
 Function: "expm1_downward":
 double: 1
-float: 1
 float128: 2
 ldouble: 4
 
 Function: "expm1_towardzero":
 double: 1
-float: 1
 float128: 4
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 float128: 3
 ldouble: 4
 
diff --git a/sysdeps/ieee754/flt-32/s_exp2m1f.c b/sysdeps/ieee754/flt-32/s_exp2m1f.c
index f899152..1ed7068 100644
--- a/sysdeps/ieee754/flt-32/s_exp2m1f.c
+++ b/sysdeps/ieee754/flt-32/s_exp2m1f.c
@@ -3,7 +3,7 @@
 Copyright (c) 2022-2024 Alexei Sibidanov.
 
 The original version of this file was copied from the CORE-MATH
-project (file src/binary32/exp2m1/exp2m1f.c, revision bc385c2).
+project (file src/binary32/exp2m1/exp2m1f.c, revision baf5f6b).
 
 Permission is hereby granted, free of charge, to any person obtaining a copy
 of this software and associated documentation files (the "Software"), to deal
diff --git a/sysdeps/ieee754/flt-32/s_expm1f.c b/sysdeps/ieee754/flt-32/s_expm1f.c
index 35f7b52..edd7c9a 100644
--- a/sysdeps/ieee754/flt-32/s_expm1f.c
+++ b/sysdeps/ieee754/flt-32/s_expm1f.c
@@ -1,132 +1,124 @@
-/* s_expm1f.c -- float version of s_expm1.c.
- */
+/* Correctly-rounded natural exponent function biased by 1 for binary32 value.
 
-/*
- * ====================================================
- * Copyright (C) 1993 by Sun Microsystems, Inc. All rights reserved.
- *
- * Developed at SunPro, a Sun Microsystems, Inc. business.
- * Permission to use, copy, modify, and distribute this
- * software is freely granted, provided that this notice
- * is preserved.
- * ====================================================
- */
+Copyright (c) 2022-2024 Alexei Sibidanov.
+
+This file is part of the CORE-MATH project
+project (file src/binary32/expm1/expm1f.c, revision bc385c2).
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in all
+copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+SOFTWARE.
+*/
 
-#include <errno.h>
-#include <float.h>
 #include <math.h>
-#include <math-barriers.h>
-#include <math_private.h>
 #include <math-underflow.h>
 #include <libm-alias-float.h>
-
-static const float huge = 1.0e+30;
-static const float tiny = 1.0e-30;
-
-static const float
-one		= 1.0,
-o_threshold	= 8.8721679688e+01,/* 0x42b17180 */
-ln2_hi		= 6.9313812256e-01,/* 0x3f317180 */
-ln2_lo		= 9.0580006145e-06,/* 0x3717f7d1 */
-invln2		= 1.4426950216e+00,/* 0x3fb8aa3b */
-	/* scaled coefficients related to expm1 */
-Q1  =  -3.3333335072e-02, /* 0xbd088889 */
-Q2  =   1.5873016091e-03, /* 0x3ad00d01 */
-Q3  =  -7.9365076090e-05, /* 0xb8a670cd */
-Q4  =   4.0082177293e-06, /* 0x36867e54 */
-Q5  =  -2.0109921195e-07; /* 0xb457edbb */
+#include "math_config.h"
 
 float
-__expm1f(float x)
+__expm1f (float x)
 {
-	float y,hi,lo,c,t,e,hxs,hfx,r1;
-	int32_t k,xsb;
-	uint32_t hx;
-
-	GET_FLOAT_WORD(hx,x);
-	xsb = hx&0x80000000;		/* sign bit of x */
-	if(xsb==0) y=x; else y= -x;	/* y = |x| */
-	hx &= 0x7fffffff;		/* high word of |x| */
-
-    /* filter out huge and non-finite argument */
-	if(hx >= 0x4195b844) {			/* if |x|>=27*ln2 */
-	    if(hx >= 0x42b17218) {		/* if |x|>=88.721... */
-		if(hx>0x7f800000)
-		    return x+x;		 /* NaN */
-		if(hx==0x7f800000)
-		    return (xsb==0)? x:-1.0;/* exp(+-inf)={inf,-1} */
-		if(x > o_threshold) {
-		  __set_errno (ERANGE);
-		  return huge*huge; /* overflow */
-		}
-	    }
-	    if(xsb!=0) { /* x < -27*ln2, return -1.0 with inexact */
-		math_force_eval(x+tiny);/* raise inexact */
-		return tiny-one;	/* return -1 */
-	    }
-	}
-
-    /* argument reduction */
-	if(hx > 0x3eb17218) {		/* if  |x| > 0.5 ln2 */
-	    if(hx < 0x3F851592) {	/* and |x| < 1.5 ln2 */
-		if(xsb==0)
-		    {hi = x - ln2_hi; lo =  ln2_lo;  k =  1;}
-		else
-		    {hi = x + ln2_hi; lo = -ln2_lo;  k = -1;}
-	    } else {
-		k  = invln2*x+((xsb==0)?(float)0.5:(float)-0.5);
-		t  = k;
-		hi = x - t*ln2_hi;	/* t*ln2_hi is exact here */
-		lo = t*ln2_lo;
-	    }
-	    x  = hi - lo;
-	    c  = (hi-x)-lo;
-	}
-	else if(hx < 0x33000000) {	/* when |x|<2**-25, return x */
-	    math_check_force_underflow (x);
-	    t = huge+x;	/* return x with inexact flags when x!=0 */
-	    return x - (t-(huge+x));
+  static const double c[] =
+    {
+      1, 0x1.62e42fef4c4e7p-6, 0x1.ebfd1b232f475p-13, 0x1.c6b19384ecd93p-20
+    };
+  static const double ch[] =
+    {
+      0x1.62e42fefa39efp-6,  0x1.ebfbdff82c58fp-13, 0x1.c6b08d702e0edp-20,
+      0x1.3b2ab6fb92e5ep-27, 0x1.5d886e6d54203p-35, 0x1.430976b8ce6efp-43
+    };
+  static const double td[] =
+    {
+      0x1p+0,               0x1.059b0d3158574p+0, 0x1.0b5586cf9890fp+0,
+      0x1.11301d0125b51p+0, 0x1.172b83c7d517bp+0, 0x1.1d4873168b9aap+0,
+      0x1.2387a6e756238p+0, 0x1.29e9df51fdee1p+0, 0x1.306fe0a31b715p+0,
+      0x1.371a7373aa9cbp+0, 0x1.3dea64c123422p+0, 0x1.44e086061892dp+0,
+      0x1.4bfdad5362a27p+0, 0x1.5342b569d4f82p+0, 0x1.5ab07dd485429p+0,
+      0x1.6247eb03a5585p+0, 0x1.6a09e667f3bcdp+0, 0x1.71f75e8ec5f74p+0,
+      0x1.7a11473eb0187p+0, 0x1.82589994cce13p+0, 0x1.8ace5422aa0dbp+0,
+      0x1.93737b0cdc5e5p+0, 0x1.9c49182a3f09p+0,  0x1.a5503b23e255dp+0,
+      0x1.ae89f995ad3adp+0, 0x1.b7f76f2fb5e47p+0, 0x1.c199bdd85529cp+0,
+      0x1.cb720dcef9069p+0, 0x1.d5818dcfba487p+0, 0x1.dfc97337b9b5fp+0,
+      0x1.ea4afa2a490dap+0, 0x1.f50765b6e454p+0
+    };
+  const double iln2 = 0x1.71547652b82fep+5;
+  const double big = 0x1.8p52;
+  double z = x;
+  uint32_t ux = asuint (x);
+  uint32_t ax = ux << 1;
+  if (__glibc_likely (ax < 0x7c400000u))
+    { /* |x| < 0.15625  */
+      if (__glibc_unlikely (ax < 0x676a09e8u))
+	{ /* |x| < 0x1.6a09e8p-24 */
+	  if (__glibc_unlikely (ax == 0x0u))
+	    return x; /* x = +-0 */
+	  return fmaf (fabsf (x), 0x1p-25f, x);
 	}
-	else k = 0;
-
-    /* x is now in primary range */
-	hfx = (float)0.5*x;
-	hxs = x*hfx;
-	r1 = one+hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5))));
-	t  = (float)3.0-r1*hfx;
-	e  = hxs*((r1-t)/((float)6.0 - x*t));
-	if(k==0) return x - (x*e-hxs);		/* c is 0 */
-	else {
-	    e  = (x*(e-c)-c);
-	    e -= hxs;
-	    if(k== -1) return (float)0.5*(x-e)-(float)0.5;
-	    if(k==1) {
-		if(x < (float)-0.25) return -(float)2.0*(e-(x+(float)0.5));
-		else	      return  one+(float)2.0*(x-e);
-	    }
-	    if (k <= -2 || k>56) {   /* suffice to return exp(x)-1 */
-		int32_t i;
-		y = one-(e-x);
-		GET_FLOAT_WORD(i,y);
-		SET_FLOAT_WORD(y,i+(k<<23));	/* add k to y's exponent */
-		return y-one;
-	    }
-	    t = one;
-	    if(k<23) {
-		int32_t i;
-		SET_FLOAT_WORD(t,0x3f800000 - (0x1000000>>k)); /* t=1-2^-k */
-		y = t-(e-x);
-		GET_FLOAT_WORD(i,y);
-		SET_FLOAT_WORD(y,i+(k<<23));	/* add k to y's exponent */
-	   } else {
-		int32_t i;
-		SET_FLOAT_WORD(t,((0x7f-k)<<23));	/* 2^-k */
-		y = x-(e+t);
-		y += one;
-		GET_FLOAT_WORD(i,y);
-		SET_FLOAT_WORD(y,i+(k<<23));	/* add k to y's exponent */
-	    }
+      static const double b[] =
+	{
+	  0x1.fffffffffffc2p-2,  0x1.55555555555fep-3,  0x1.555555559767fp-5,
+	  0x1.1111111098dc1p-7,  0x1.6c16bca988aa9p-10, 0x1.a01a07658483fp-13,
+	  0x1.a05b04d2c3503p-16, 0x1.71de3a960b5e3p-19
+	};
+      double z2 = z * z, z4 = z2 * z2;
+      double r = z + z2
+	* ((b[0] + z * b[1]) + z2 * (b[2] + z * b[3])
+	   + z4 * ((b[4] + z * b[5]) + z2 * (b[6] + z * b[7])));
+      return r;
+    }
+  if (__glibc_unlikely (ax >= 0x8562e430u))
+    { /* |x| > 88.72 */
+      if (ax > (0xffu << 24))
+	return x + x; /* nan */
+      if (__glibc_unlikely (ux >> 31))
+	{ /* x < 0 */
+	  if (ax == (0xffu << 24))
+	    return -1.0f;
+	  return -1.0f + 0x1p-26f;
 	}
-	return y;
+      if (ax == (0xffu << 24))
+	return INFINITY;
+      return __math_oflowf (0);
+    }
+  double a = iln2 * z;
+  double ia = roundeven (a);
+  double h = a - ia;
+  double h2 = h * h;
+  uint64_t u = asuint64 (ia + big);
+  double c2 = c[2] + h * c[3], c0 = c[0] + h * c[1];
+  const uint64_t *tdl = (uint64_t *) ((void *) td);
+  double sv = asdouble (tdl[u & 0x1f] + ((u >> 5) << 52));
+  double r = (c0 + h2 * c2) * sv - 1.0;
+  float ub = r, lb = r - sv * 0x1.3b3p-33;
+  if (__glibc_unlikely (ub != lb))
+    {
+      if (__glibc_unlikely (ux > 0xc18aa123u)) /* x < -17.32 */
+	return -1.0f + 0x1p-26f;
+      const double iln2h = 0x1.7154765p+5;
+      const double iln2l = 0x1.5c17f0bbbe88p-26;
+      double s = sv;
+      h = (iln2h * z - ia) + iln2l * z;
+      h2 = h * h;
+      double w = s * h;
+      r = (s - 1) + w
+	* ((ch[0] + h * ch[1])
+	   + h2 * ((ch[2] + h * ch[3]) + h2 * (ch[4] + h * ch[5])));
+      ub = r;
+    }
+  return ub;
 }
 libm_alias_float (__expm1, expm1)
diff --git a/sysdeps/loongarch/lp64/libm-test-ulps b/sysdeps/loongarch/lp64/libm-test-ulps
index c6fc9fd..5d407a4 100644
--- a/sysdeps/loongarch/lp64/libm-test-ulps
+++ b/sysdeps/loongarch/lp64/libm-test-ulps
@@ -1038,22 +1038,18 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/microblaze/libm-test-ulps b/sysdeps/microblaze/libm-test-ulps
index 98ea940..a84494b 100644
--- a/sysdeps/microblaze/libm-test-ulps
+++ b/sysdeps/microblaze/libm-test-ulps
@@ -191,7 +191,6 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/mips/mips32/libm-test-ulps b/sysdeps/mips/mips32/libm-test-ulps
index d8daca6..f9d7bf8 100644
--- a/sysdeps/mips/mips32/libm-test-ulps
+++ b/sysdeps/mips/mips32/libm-test-ulps
@@ -831,19 +831,15 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/mips/mips64/libm-test-ulps b/sysdeps/mips/mips64/libm-test-ulps
index 39e94d5..4f3c82d 100644
--- a/sysdeps/mips/mips64/libm-test-ulps
+++ b/sysdeps/mips/mips64/libm-test-ulps
@@ -1042,22 +1042,18 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/nios2/libm-test-ulps b/sysdeps/nios2/libm-test-ulps
index df6e932..33f714e 100644
--- a/sysdeps/nios2/libm-test-ulps
+++ b/sysdeps/nios2/libm-test-ulps
@@ -197,7 +197,6 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/or1k/fpu/libm-test-ulps b/sysdeps/or1k/fpu/libm-test-ulps
index 4ccb136..9ced4b0 100644
--- a/sysdeps/or1k/fpu/libm-test-ulps
+++ b/sysdeps/or1k/fpu/libm-test-ulps
@@ -804,19 +804,15 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/or1k/nofpu/libm-test-ulps b/sysdeps/or1k/nofpu/libm-test-ulps
index 7087cf9..6862551 100644
--- a/sysdeps/or1k/nofpu/libm-test-ulps
+++ b/sysdeps/or1k/nofpu/libm-test-ulps
@@ -802,19 +802,15 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "expm1_upward":
 double: 1
-float: 1
 
 Function: "gamma":
 double: 4
diff --git a/sysdeps/powerpc/fpu/libm-test-ulps b/sysdeps/powerpc/fpu/libm-test-ulps
index dd25aaf..ddbd184 100644
--- a/sysdeps/powerpc/fpu/libm-test-ulps
+++ b/sysdeps/powerpc/fpu/libm-test-ulps
@@ -870,6 +870,7 @@ float128: 1
 ldouble: 2
 
 Function: Imaginary part of "csin":
+float: 1
 float128: 1
 ldouble: 1
 
@@ -1262,25 +1263,21 @@ ldouble: 1
 
 Function: "expm1":
 double: 1
-float: 1
 float128: 2
 ldouble: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 float128: 2
 ldouble: 7
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 float128: 4
 ldouble: 6
 
 Function: "expm1_upward":
 double: 1
-float: 1
 float128: 3
 ldouble: 6
 
diff --git a/sysdeps/powerpc/nofpu/libm-test-ulps b/sysdeps/powerpc/nofpu/libm-test-ulps
index 1e5bae0..c79dfcc 100644
--- a/sysdeps/powerpc/nofpu/libm-test-ulps
+++ b/sysdeps/powerpc/nofpu/libm-test-ulps
@@ -1054,22 +1054,18 @@ ldouble: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 1
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 5
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 5
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 6
 
 Function: "fma":
diff --git a/sysdeps/riscv/nofpu/libm-test-ulps b/sysdeps/riscv/nofpu/libm-test-ulps
index 11f8919..4caf84f 100644
--- a/sysdeps/riscv/nofpu/libm-test-ulps
+++ b/sysdeps/riscv/nofpu/libm-test-ulps
@@ -1011,22 +1011,18 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/riscv/rvd/libm-test-ulps b/sysdeps/riscv/rvd/libm-test-ulps
index 7d303fc..e9c4b72 100644
--- a/sysdeps/riscv/rvd/libm-test-ulps
+++ b/sysdeps/riscv/rvd/libm-test-ulps
@@ -1038,22 +1038,18 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/s390/fpu/libm-test-ulps b/sysdeps/s390/fpu/libm-test-ulps
index aa7a94a..a42c9f2 100644
--- a/sysdeps/s390/fpu/libm-test-ulps
+++ b/sysdeps/s390/fpu/libm-test-ulps
@@ -1039,22 +1039,18 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/sh/libm-test-ulps b/sysdeps/sh/libm-test-ulps
index 36f21ed..fc4556e 100644
--- a/sysdeps/sh/libm-test-ulps
+++ b/sysdeps/sh/libm-test-ulps
@@ -394,11 +394,9 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 
 Function: "fma_towardzero":
 double: 1
diff --git a/sysdeps/sparc/fpu/libm-test-ulps b/sysdeps/sparc/fpu/libm-test-ulps
index e7b3da6..3bee496 100644
--- a/sysdeps/sparc/fpu/libm-test-ulps
+++ b/sysdeps/sparc/fpu/libm-test-ulps
@@ -1042,22 +1042,18 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_downward":
 double: 1
-float: 1
 ldouble: 2
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 ldouble: 3
 
 Function: "gamma":
diff --git a/sysdeps/x86_64/fpu/libm-test-ulps b/sysdeps/x86_64/fpu/libm-test-ulps
index 71697e9..ffb1d4f 100644
--- a/sysdeps/x86_64/fpu/libm-test-ulps
+++ b/sysdeps/x86_64/fpu/libm-test-ulps
@@ -1062,6 +1062,7 @@ float128: 1
 ldouble: 1
 
 Function: Imaginary part of "csin":
+float: 1
 float128: 1
 
 Function: Real part of "csin_downward":
@@ -1550,25 +1551,21 @@ float: 1
 
 Function: "expm1":
 double: 1
-float: 1
 float128: 2
 ldouble: 3
 
 Function: "expm1_downward":
 double: 1
-float: 1
 float128: 2
 ldouble: 4
 
 Function: "expm1_towardzero":
 double: 1
-float: 2
 float128: 4
 ldouble: 4
 
 Function: "expm1_upward":
 double: 1
-float: 1
 float128: 3
 ldouble: 4