[02/10] i386: Replace assembly versions of e_expf with generic e_expf.c

Message ID 20171019173159.21402-3-hjl.tools@gmail.com
State New, archived
Headers

Commit Message

H.J. Lu Oct. 19, 2017, 5:31 p.m. UTC
  This patch replaces i386 assembly versions of e_expf with generic
e_expf.c.  For workload-spec2017.wrf, on Nehalem, it improves
performance by:

                           Before            After     Improvement
reciprocal-throughput      55.5724          40.2664       38%
latency                    80.0687          60.8517       31%

On Skylake, it improves performance by:

                           Before            After     Improvement
reciprocal-throughput      62.4056          39.4188       58%
latency                    85.5496          59.6377       43%

	* sysdeps/i386/fpu/e_exp2f_data.c: Removed.
	* sysdeps/i386/fpu/e_expf.S: Likewise.
	* sysdeps/i386/fpu/math_errf.c: Likewise.
	* sysdeps/i386/fpu/w_expf.c: Likewise.
	* sysdeps/i386/i686/fpu/multiarch/e_expf-ia32.S: Likewise.
	* sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S: Likewise.
	* sysdeps/i386/i686/fpu/multiarch/w_expf.c: Likewise.
	* sysdeps/i386/fpu/libm-test-ulps: Updated for generic e_expf.c.
	* sysdeps/i386/i686/fpu/multiarch/libm-test-ulps: Likewise.
	* sysdeps/i386/i686/fpu/multiarch/Makefile (libm-sysdep_routines):
	Remove e_expf-ia32.
	(CFLAGS-e_expf-sse2.c): New.
	* sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.c: New file.
	* sysdeps/i386/i686/fpu/multiarch/e_expf.c: Rewritten.
---
 sysdeps/i386/fpu/e_exp2f_data.c                |   1 -
 sysdeps/i386/fpu/e_expf.S                      |  74 ------
 sysdeps/i386/fpu/libm-test-ulps                |   6 +
 sysdeps/i386/fpu/math_errf.c                   |   1 -
 sysdeps/i386/fpu/w_expf.c                      |   1 -
 sysdeps/i386/i686/fpu/multiarch/Makefile       |   4 +-
 sysdeps/i386/i686/fpu/multiarch/e_expf-ia32.S  |  22 --
 sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S  | 325 -------------------------
 sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.c  |   3 +
 sysdeps/i386/i686/fpu/multiarch/e_expf.c       |  35 +--
 sysdeps/i386/i686/fpu/multiarch/libm-test-ulps |   4 +
 sysdeps/i386/i686/fpu/multiarch/w_expf.c       |   1 -
 12 files changed, 35 insertions(+), 442 deletions(-)
 delete mode 100644 sysdeps/i386/fpu/e_exp2f_data.c
 delete mode 100644 sysdeps/i386/fpu/e_expf.S
 delete mode 100644 sysdeps/i386/fpu/math_errf.c
 delete mode 100644 sysdeps/i386/fpu/w_expf.c
 delete mode 100644 sysdeps/i386/i686/fpu/multiarch/e_expf-ia32.S
 delete mode 100644 sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S
 create mode 100644 sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.c
 delete mode 100644 sysdeps/i386/i686/fpu/multiarch/w_expf.c
  

Comments

Joseph Myers Oct. 19, 2017, 5:44 p.m. UTC | #1
I think there should also be --disable-multi-arch benchmark results here.  
Likewise for other i386 functions in this series (as otherwise all of the 
x86 benchmarks you give are testing the multiarch/*-sse2.c case only, 
nothing is testing the generic fallback of the C version built to use x87 
arithmetic - which I expect is still very likely to be faster than the old 
.S implementation, and you might justify removing the .S versions even if 
the .c versions built for x87 aren't faster, but benchmark results for 
that case should still be given).
  
H.J. Lu Oct. 19, 2017, 7:49 p.m. UTC | #2
On Thu, Oct 19, 2017 at 10:44 AM, Joseph Myers <joseph@codesourcery.com> wrote:
> I think there should also be --disable-multi-arch benchmark results here.
> Likewise for other i386 functions in this series (as otherwise all of the
> x86 benchmarks you give are testing the multiarch/*-sse2.c case only,
> nothing is testing the generic fallback of the C version built to use x87
> arithmetic - which I expect is still very likely to be faster than the old
> .S implementation, and you might justify removing the .S versions even if
> the .c versions built for x87 aren't faster, but benchmark results for
> that case should still be given).
>

With --disable-multi-arch, generic version is faster than x87 assembly
version:

  On IvyBridge with --disable-multi-arch, it improves performance by:

                           Before            After     Improvement
reciprocal-throughput      133.707          40.3778       231%
latency                    149.191          63.2515       135%
  

Patch

diff --git a/sysdeps/i386/fpu/e_exp2f_data.c b/sysdeps/i386/fpu/e_exp2f_data.c
deleted file mode 100644
index 1cc8931700..0000000000
--- a/sysdeps/i386/fpu/e_exp2f_data.c
+++ /dev/null
@@ -1 +0,0 @@ 
-/* Not needed.  */
diff --git a/sysdeps/i386/fpu/e_expf.S b/sysdeps/i386/fpu/e_expf.S
deleted file mode 100644
index 65cb4ec204..0000000000
--- a/sysdeps/i386/fpu/e_expf.S
+++ /dev/null
@@ -1,74 +0,0 @@ 
-/*
- * Written by J.T. Conklin <jtc@netbsd.org>.
- * Public domain.
- * Adapted for float type by Ulrich Drepper <drepper@cygnus.com>.
- */
-
-#include <machine/asm.h>
-#include <i386-math-asm.h>
-
-DEFINE_FLT_MIN
-
-#ifdef PIC
-# define MO(op) op##@GOTOFF(%ecx)
-#else
-# define MO(op) op
-#endif
-
-	.text
-/* e^x = 2^(x * log2(e)) */
-ENTRY(__ieee754_expf)
-#ifdef  PIC
-	LOAD_PIC_REG (cx)
-#endif
-	flds	4(%esp)
-/* I added the following ugly construct because exp(+-Inf) resulted
-   in NaN.  The ugliness results from the bright minds at Intel.
-   For the i686 the code can be written better.
-   -- drepper@cygnus.com.  */
-	fxam				/* Is NaN or +-Inf?  */
-	fstsw	%ax
-	movb	$0x45, %dh
-	andb	%ah, %dh
-	cmpb	$0x05, %dh
-	je	1f			/* Is +-Inf, jump.  */
-	fldl2e
-	fmulp				/* x * log2(e) */
-	fld	%st
-	frndint				/* int(x * log2(e)) */
-	fsubr	%st,%st(1)		/* fract(x * log2(e)) */
-	fxch
-	f2xm1				/* 2^(fract(x * log2(e))) - 1 */
-	fld1
-	faddp				/* 2^(fract(x * log2(e))) */
-	fscale				/* e^x */
-	fstp	%st(1)
-	FLT_NARROW_EVAL_UFLOW_NONNEG_NAN
-	ret
-
-1:	testl	$0x200, %eax		/* Test sign.  */
-	jz	2f			/* If positive, jump.  */
-	fstp	%st
-	fldz				/* Set result to 0.  */
-2:	ret
-END (__ieee754_expf)
-
-
-ENTRY(__expf_finite)
-#ifdef  PIC
-	LOAD_PIC_REG (cx)
-#endif
-	fldl2e
-	fmuls	4(%esp)			/* x * log2(e) */
-	fld	%st
-	frndint				/* int(x * log2(e)) */
-	fsubr	%st,%st(1)		/* fract(x * log2(e)) */
-	fxch
-	f2xm1				/* 2^(fract(x * log2(e))) - 1 */
-	fld1
-	faddp				/* 2^(fract(x * log2(e))) */
-	fscale				/* e^x */
-	fstp	%st(1)
-	FLT_NARROW_EVAL_UFLOW_NONNEG
-	ret
-END(__expf_finite)
diff --git a/sysdeps/i386/fpu/libm-test-ulps b/sysdeps/i386/fpu/libm-test-ulps
index 68017a511e..60a721c000 100644
--- a/sysdeps/i386/fpu/libm-test-ulps
+++ b/sysdeps/i386/fpu/libm-test-ulps
@@ -1928,19 +1928,25 @@  ldouble: 1
 
 Function: "exp_downward":
 double: 1
+float: 1
 idouble: 1
+ifloat: 1
 ildouble: 1
 ldouble: 1
 
 Function: "exp_towardzero":
 double: 1
+float: 1
 idouble: 1
+ifloat: 1
 ildouble: 2
 ldouble: 2
 
 Function: "exp_upward":
 double: 1
+float: 1
 idouble: 1
+ifloat: 1
 ildouble: 1
 ldouble: 1
 
diff --git a/sysdeps/i386/fpu/math_errf.c b/sysdeps/i386/fpu/math_errf.c
deleted file mode 100644
index 1cc8931700..0000000000
--- a/sysdeps/i386/fpu/math_errf.c
+++ /dev/null
@@ -1 +0,0 @@ 
-/* Not needed.  */
diff --git a/sysdeps/i386/fpu/w_expf.c b/sysdeps/i386/fpu/w_expf.c
deleted file mode 100644
index b5fe164520..0000000000
--- a/sysdeps/i386/fpu/w_expf.c
+++ /dev/null
@@ -1 +0,0 @@ 
-#include <sysdeps/../math/w_expf.c>
diff --git a/sysdeps/i386/i686/fpu/multiarch/Makefile b/sysdeps/i386/i686/fpu/multiarch/Makefile
index 7d9089232f..c5e8cfd689 100644
--- a/sysdeps/i386/i686/fpu/multiarch/Makefile
+++ b/sysdeps/i386/i686/fpu/multiarch/Makefile
@@ -1,4 +1,6 @@ 
 ifeq ($(subdir),math)
-libm-sysdep_routines += e_expf-sse2 e_expf-ia32 s_sinf-sse2 s_cosf-sse2 \
+libm-sysdep_routines += e_expf-sse2 s_sinf-sse2 s_cosf-sse2 \
                         s_sincosf-sse2
+
+CFLAGS-e_expf-sse2.c = -msse2 -mfpmath=sse
 endif
diff --git a/sysdeps/i386/i686/fpu/multiarch/e_expf-ia32.S b/sysdeps/i386/i686/fpu/multiarch/e_expf-ia32.S
deleted file mode 100644
index b486b4d1ca..0000000000
--- a/sysdeps/i386/i686/fpu/multiarch/e_expf-ia32.S
+++ /dev/null
@@ -1,22 +0,0 @@ 
-/*
-   Copyright (C) 2012-2017 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
-   <http://www.gnu.org/licenses/>.  */
-
-#define __ieee754_expf __ieee754_expf_ia32
-#define __expf_finite __expf_finite_ia32
-
-#include <sysdeps/i386/fpu/e_expf.S>
diff --git a/sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S b/sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S
deleted file mode 100644
index e6bb6fa289..0000000000
--- a/sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.S
+++ /dev/null
@@ -1,325 +0,0 @@ 
-/* SSE2 version of __ieee754_expf and __expf_finite
-   Copyright (C) 2012-2017 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
-   <http://www.gnu.org/licenses/>.  */
-
-
-#include <sysdep.h>
-
-/* Short algorithm description:
- *
- *  Let K = 64 (table size).
- *       e^x  = 2^(x/log(2)) = 2^n * T[j] * (1 + P(y))
- *  where
- *       x = m*log(2)/K + y,    y in [0.0..log(2)/K]
- *       m = n*K + j,           m,n,j - signed integer, j in [0..K-1]
- *       values of 2^(j/K) are tabulated as T[j].
- *
- *       P(y) is a minimax polynomial approximation of expf(x)-1
- *       on small interval [0.0..log(2)/K].
- *
- *       P(y) = P3*y*y*y*y + P2*y*y*y + P1*y*y + P0*y, calculated as
- *       z = y*y;    P(y) = (P3*z + P1)*z + (P2*z + P0)*y
- *
- * Special cases:
- *  __ieee754_expf_sse2(NaN) = NaN
- *  __ieee754_expf_sse2(+INF) = +INF
- *  __ieee754_expf_sse2(-INF) = 0
- *  __ieee754_expf_sse2(x) = 1 for subnormals
- *  for finite argument, only __ieee754_expf_sse2(0)=1 is exact
- *  __ieee754_expf_sse2(x) overflows if x>700
- *  __ieee754_expf_sse2(x) underflows if x<-700
- *
- * Note:
- *  For |x|<700, __ieee754_expf_sse2 computes result in double precision,
- *  with accuracy a bit more than needed for expf, and does not round it
- *  to single precision.
- */
-
-
-#ifdef	PIC
-# define MO1(symbol)			L(symbol)##@GOTOFF(%edx)
-# define MO2(symbol,reg2,_scale)	L(symbol)##@GOTOFF(%edx,reg2,_scale)
-#else
-# define MO1(symbol)			L(symbol)
-# define MO2(symbol,reg2,_scale)	L(symbol)(,reg2,_scale)
-#endif
-
-	.text
-ENTRY(__ieee754_expf_sse2)
-	/* Input: single precision x on stack at address 4(%esp) */
-
-#ifdef	PIC
-	LOAD_PIC_REG(dx)
-#endif
-
-	cvtss2sd	4(%esp), %xmm1	/* Convert x to double precision */
-	mov	4(%esp), %ecx		/* Copy x */
-	movsd	MO1(DP_KLN2), %xmm2	/* DP K/log(2) */
-	movsd	MO1(DP_P2), %xmm3	/* DP P2 */
-	movl	%ecx, %eax		/* x */
-	mulsd	%xmm1, %xmm2		/* DP x*K/log(2) */
-	andl	$0x7fffffff, %ecx	/* |x| */
-	cmpl	$0x442f0000, %ecx	/* |x|<700 ? */
-	movsd	MO1(DP_P3), %xmm4	/* DP P3 */
-	addsd	MO1(DP_RS), %xmm2	/* DP x*K/log(2)+RS */
-	jae	L(special_paths)
-
-	/* Here if |x|<700 */
-	cmpl	$0x31800000, %ecx	/* |x|<2^(-28) ? */
-	jb	L(small_arg)
-
-	/* Main path: here if 2^(-28)<=|x|<700 */
-	cvtsd2ss	%xmm2, %xmm2	/* SP x*K/log(2)+RS */
-	movd	%xmm2, %eax		/* bits of n*K+j with trash */
-	subss	MO1(SP_RS), %xmm2	/* SP t=round(x*K/log(2)) */
-	movl	%eax, %ecx		/* n*K+j with trash */
-	cvtss2sd	%xmm2, %xmm2	/* DP t */
-	andl	$0x3f, %eax		/* bits of j */
-	mulsd	MO1(DP_NLN2K), %xmm2	/* DP -t*log(2)/K */
-	andl	$0xffffffc0, %ecx	/* bits of n */
-#ifdef __AVX__
-	vaddsd	%xmm1, %xmm2, %xmm0	/* DP y=x-t*log(2)/K */
-	vmulsd	%xmm0, %xmm0, %xmm2	/* DP z=y*y */
-#else
-	addsd	%xmm1, %xmm2		/* DP y=x-t*log(2)/K */
-	movaps	%xmm2, %xmm0		/* DP y */
-	mulsd	%xmm2, %xmm2		/* DP z=y*y */
-#endif
-	mulsd	%xmm2, %xmm4		/* DP P3*z */
-	addl	$0xffc0, %ecx		/* bits of n + DP exponent bias */
-	mulsd	%xmm2, %xmm3		/* DP P2*z */
-	shrl	$2, %ecx		/* High 2 bytes of DP 2^n */
-	pxor	%xmm1, %xmm1		/* clear %xmm1 */
-	addsd	MO1(DP_P1), %xmm4	/* DP P3*z+P1 */
-	addsd	MO1(DP_P0), %xmm3	/* DP P2*z+P0 */
-	pinsrw	$3, %ecx, %xmm1		/* DP 2^n */
-	mulsd	%xmm2, %xmm4		/* DP (P3*z+P1)*z */
-	mulsd	%xmm3, %xmm0		/* DP (P2*z+P0)*y */
-	addsd	%xmm4, %xmm0		/* DP P(y) */
-	mulsd	MO2(DP_T,%eax,8), %xmm0	/* DP P(y)*T[j] */
-	addsd	MO2(DP_T,%eax,8), %xmm0	/* DP T[j]*(P(y)+1) */
-	mulsd	%xmm1, %xmm0		/* DP result=2^n*(T[j]*(P(y)+1)) */
-	cvtsd2ss	%xmm0, %xmm1
-
-	lea	-4(%esp), %esp		/* Borrow 4 bytes of stack frame */
-	movss	%xmm1, 0(%esp)		/* Move result from sse... */
-	flds	0(%esp)			/* ...to FPU. */
-	lea	4(%esp), %esp		/* Return back 4 bytes of stack frame */
-	ret
-
-	.p2align	4
-L(small_arg):
-	/* Here if 0<=|x|<2^(-28) */
-	movss	4(%esp), %xmm0		/* load x */
-	addss	MO1(SP_ONE), %xmm0	/* 1.0 + x */
-	/* Return 1.0 with inexact raised, except for x==0 */
-	jmp	L(epilogue)
-
-	.p2align	4
-L(special_paths):
-	/* Here if x is NaN, or Inf, or finite |x|>=700 */
-	movss	4(%esp), %xmm0		/* load x */
-
-	cmpl	$0x7f800000, %ecx	/* |x| is finite ? */
-	jae	L(arg_inf_or_nan)
-
-	/* Here if finite |x|>=700 */
-	testl	$0x80000000, %eax	/* sign of x nonzero ? */
-	je	L(res_overflow)
-
-	/* Here if finite x<=-700 */
-	movss	MO1(SP_SMALL), %xmm0	/* load small value 2^(-100) */
-	mulss	%xmm0, %xmm0		/* Return underflowed result (zero or subnormal) */
-	jmp	L(epilogue)
-
-	.p2align	4
-L(res_overflow):
-	/* Here if finite x>=700 */
-	movss	MO1(SP_LARGE), %xmm0	/* load large value 2^100 */
-	mulss	%xmm0, %xmm0		/* Return overflowed result (Inf or max normal) */
-	jmp	L(epilogue)
-
-	.p2align	4
-L(arg_inf_or_nan):
-	/* Here if |x| is Inf or NAN */
-	jne	L(arg_nan)	/* |x| is Inf ? */
-
-	/* Here if |x| is Inf */
-	shrl	$31, %eax		/* Get sign bit of x */
-	movss	MO2(SP_INF_0,%eax,4), %xmm0/* return zero or Inf, depending on sign of x */
-	jmp	L(epilogue)
-
-	.p2align	4
-L(arg_nan):
-	/* Here if |x| is NaN */
-	addss	%xmm0, %xmm0		/* Return x+x (raise invalid) */
-
-	.p2align	4
-L(epilogue):
-	lea	-4(%esp), %esp		/* Borrow 4 bytes of stack frame */
-	movss	%xmm0, 0(%esp)		/* Move result from sse... */
-	flds	0(%esp)			/* ...to FPU. */
-	lea	4(%esp), %esp		/* Return back 4 bytes of stack frame */
-	ret
-END(__ieee754_expf_sse2)
-
-	.section .rodata, "a"
-	.p2align 3
-L(DP_T): /* table of double precision values 2^(j/K) for j=[0..K-1] */
-	.long	0x00000000, 0x3ff00000
-	.long	0x3e778061, 0x3ff02c9a
-	.long	0xd3158574, 0x3ff059b0
-	.long	0x18759bc8, 0x3ff08745
-	.long	0x6cf9890f, 0x3ff0b558
-	.long	0x32d3d1a2, 0x3ff0e3ec
-	.long	0xd0125b51, 0x3ff11301
-	.long	0xaea92de0, 0x3ff1429a
-	.long	0x3c7d517b, 0x3ff172b8
-	.long	0xeb6fcb75, 0x3ff1a35b
-	.long	0x3168b9aa, 0x3ff1d487
-	.long	0x88628cd6, 0x3ff2063b
-	.long	0x6e756238, 0x3ff2387a
-	.long	0x65e27cdd, 0x3ff26b45
-	.long	0xf51fdee1, 0x3ff29e9d
-	.long	0xa6e4030b, 0x3ff2d285
-	.long	0x0a31b715, 0x3ff306fe
-	.long	0xb26416ff, 0x3ff33c08
-	.long	0x373aa9cb, 0x3ff371a7
-	.long	0x34e59ff7, 0x3ff3a7db
-	.long	0x4c123422, 0x3ff3dea6
-	.long	0x21f72e2a, 0x3ff4160a
-	.long	0x6061892d, 0x3ff44e08
-	.long	0xb5c13cd0, 0x3ff486a2
-	.long	0xd5362a27, 0x3ff4bfda
-	.long	0x769d2ca7, 0x3ff4f9b2
-	.long	0x569d4f82, 0x3ff5342b
-	.long	0x36b527da, 0x3ff56f47
-	.long	0xdd485429, 0x3ff5ab07
-	.long	0x15ad2148, 0x3ff5e76f
-	.long	0xb03a5585, 0x3ff6247e
-	.long	0x82552225, 0x3ff66238
-	.long	0x667f3bcd, 0x3ff6a09e
-	.long	0x3c651a2f, 0x3ff6dfb2
-	.long	0xe8ec5f74, 0x3ff71f75
-	.long	0x564267c9, 0x3ff75feb
-	.long	0x73eb0187, 0x3ff7a114
-	.long	0x36cf4e62, 0x3ff7e2f3
-	.long	0x994cce13, 0x3ff82589
-	.long	0x9b4492ed, 0x3ff868d9
-	.long	0x422aa0db, 0x3ff8ace5
-	.long	0x99157736, 0x3ff8f1ae
-	.long	0xb0cdc5e5, 0x3ff93737
-	.long	0x9fde4e50, 0x3ff97d82
-	.long	0x82a3f090, 0x3ff9c491
-	.long	0x7b5de565, 0x3ffa0c66
-	.long	0xb23e255d, 0x3ffa5503
-	.long	0x5579fdbf, 0x3ffa9e6b
-	.long	0x995ad3ad, 0x3ffae89f
-	.long	0xb84f15fb, 0x3ffb33a2
-	.long	0xf2fb5e47, 0x3ffb7f76
-	.long	0x904bc1d2, 0x3ffbcc1e
-	.long	0xdd85529c, 0x3ffc199b
-	.long	0x2e57d14b, 0x3ffc67f1
-	.long	0xdcef9069, 0x3ffcb720
-	.long	0x4a07897c, 0x3ffd072d
-	.long	0xdcfba487, 0x3ffd5818
-	.long	0x03db3285, 0x3ffda9e6
-	.long	0x337b9b5f, 0x3ffdfc97
-	.long	0xe78b3ff6, 0x3ffe502e
-	.long	0xa2a490da, 0x3ffea4af
-	.long	0xee615a27, 0x3ffefa1b
-	.long	0x5b6e4540, 0x3fff5076
-	.long	0x819e90d8, 0x3fffa7c1
-	.type L(DP_T), @object
-	ASM_SIZE_DIRECTIVE(L(DP_T))
-
-	.section .rodata.cst8,"aM",@progbits,8
-	.p2align 3
-L(DP_KLN2): /* double precision K/log(2) */
-	.long	0x652b82fe, 0x40571547
-	.type L(DP_KLN2), @object
-	ASM_SIZE_DIRECTIVE(L(DP_KLN2))
-
-	.p2align 3
-L(DP_NLN2K): /* double precision -log(2)/K */
-	.long	0xfefa39ef, 0xbf862e42
-	.type L(DP_NLN2K), @object
-	ASM_SIZE_DIRECTIVE(L(DP_NLN2K))
-
-	.p2align 3
-L(DP_RS): /* double precision 2^23+2^22 */
-	.long	0x00000000, 0x41680000
-	.type L(DP_RS), @object
-	ASM_SIZE_DIRECTIVE(L(DP_RS))
-
-	.p2align 3
-L(DP_P3): /* double precision polynomial coefficient P3 */
-	.long	0xeb78fa85, 0x3fa56420
-	.type L(DP_P3), @object
-	ASM_SIZE_DIRECTIVE(L(DP_P3))
-
-	.p2align 3
-L(DP_P1): /* double precision polynomial coefficient P1 */
-	.long	0x008d6118, 0x3fe00000
-	.type L(DP_P1), @object
-	ASM_SIZE_DIRECTIVE(L(DP_P1))
-
-	.p2align 3
-L(DP_P2): /* double precision polynomial coefficient P2 */
-	.long	0xda752d4f, 0x3fc55550
-	.type L(DP_P2), @object
-	ASM_SIZE_DIRECTIVE(L(DP_P2))
-
-	.p2align 3
-L(DP_P0): /* double precision polynomial coefficient P0 */
-	.long	0xffffe7c6, 0x3fefffff
-	.type L(DP_P0), @object
-	ASM_SIZE_DIRECTIVE(L(DP_P0))
-
-	.p2align 2
-L(SP_INF_0):
-	.long	0x7f800000	/* single precision Inf */
-	.long	0		/* single precision zero */
-	.type L(SP_INF_0), @object
-	ASM_SIZE_DIRECTIVE(L(SP_INF_0))
-
-	.section .rodata.cst4,"aM",@progbits,4
-	.p2align 2
-L(SP_RS): /* single precision 2^23+2^22 */
-	.long	0x4b400000
-	.type L(SP_RS), @object
-	ASM_SIZE_DIRECTIVE(L(SP_RS))
-
-	.p2align 2
-L(SP_SMALL): /* single precision small value 2^(-100) */
-	.long	0x0d800000
-	.type L(SP_SMALL), @object
-	ASM_SIZE_DIRECTIVE(L(SP_SMALL))
-
-	.p2align 2
-L(SP_LARGE): /* single precision large value 2^100 */
-	.long	0x71800000
-	.type L(SP_LARGE), @object
-	ASM_SIZE_DIRECTIVE(L(SP_LARGE))
-
-	.p2align 2
-L(SP_ONE): /* single precision 1.0 */
-	.long	0x3f800000
-	.type L(SP_ONE), @object
-	ASM_SIZE_DIRECTIVE(L(SP_ONE))
-
-strong_alias (__ieee754_expf_sse2, __expf_finite_sse2)
diff --git a/sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.c b/sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.c
new file mode 100644
index 0000000000..7c758e6556
--- /dev/null
+++ b/sysdeps/i386/i686/fpu/multiarch/e_expf-sse2.c
@@ -0,0 +1,3 @@ 
+#define __expf __expf_sse2
+
+#include <sysdeps/ieee754/flt-32/e_expf.c>
diff --git a/sysdeps/i386/i686/fpu/multiarch/e_expf.c b/sysdeps/i386/i686/fpu/multiarch/e_expf.c
index 388cf98a39..bd4240e560 100644
--- a/sysdeps/i386/i686/fpu/multiarch/e_expf.c
+++ b/sysdeps/i386/i686/fpu/multiarch/e_expf.c
@@ -1,4 +1,4 @@ 
-/* Multiple versions of expf
+/* Multiple versions of expf.
    Copyright (C) 2012-2017 Free Software Foundation, Inc.
    This file is part of the GNU C Library.
 
@@ -16,22 +16,25 @@ 
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
-#include <init-arch.h>
+extern float __redirect_expf (float);
 
-extern double __ieee754_expf_sse2 (double);
-extern double __ieee754_expf_ia32 (double);
+#define SYMBOL_NAME expf
+#include "ifunc-sse2.h"
 
-double __ieee754_expf (double);
-libm_ifunc (__ieee754_expf,
-	    HAS_CPU_FEATURE (SSE2)
-	    ? __ieee754_expf_sse2
-	    : __ieee754_expf_ia32);
+libc_ifunc_redirected (__redirect_expf, __expf, IFUNC_SELECTOR ());
 
-extern double __expf_finite_sse2 (double);
-extern double __expf_finite_ia32 (double);
+#ifdef SHARED
+__hidden_ver1 (__expf_ia32, __GI___expf, __redirect_expf)
+  __attribute__ ((visibility ("hidden")));
 
-double __expf_finite (double);
-libm_ifunc (__expf_finite,
-	    HAS_CPU_FEATURE (SSE2)
-	    ? __expf_finite_sse2
-	    : __expf_finite_ia32);
+# include <shlib-compat.h>
+versioned_symbol (libm, __expf, expf, GLIBC_2_27);
+#else
+weak_alias (__expf, expf)
+#endif
+
+strong_alias (__expf, __ieee754_expf)
+strong_alias (__expf, __expf_finite)
+
+#define __expf __expf_ia32
+#include <sysdeps/ieee754/flt-32/e_expf.c>
diff --git a/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps b/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
index d81c28ba95..5ff641f848 100644
--- a/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
+++ b/sysdeps/i386/i686/fpu/multiarch/libm-test-ulps
@@ -1928,13 +1928,17 @@  ldouble: 1
 
 Function: "exp_downward":
 double: 1
+float: 1
 idouble: 1
+ifloat: 1
 ildouble: 1
 ldouble: 1
 
 Function: "exp_towardzero":
 double: 1
+float: 1
 idouble: 1
+ifloat: 1
 ildouble: 2
 ldouble: 2
 
diff --git a/sysdeps/i386/i686/fpu/multiarch/w_expf.c b/sysdeps/i386/i686/fpu/multiarch/w_expf.c
deleted file mode 100644
index b5fe164520..0000000000
--- a/sysdeps/i386/i686/fpu/multiarch/w_expf.c
+++ /dev/null
@@ -1 +0,0 @@ 
-#include <sysdeps/../math/w_expf.c>