Fix ilogb(3) implementation. The results have to match FP_ILOGB0 and

FP_ILOGBNAN which isn't the case for the amd64 and i386 assembly versions.
Drop these in favour of C implementations.  Als reimplement ilogbl(3)
by providing separate ld80 and ld128 implementations that replace the
existing implementation which may hit an infinite loop when built for
quad-precision long double.

ok patrick@, gkoehler@

5 files changed, 3 insertions, 89 deletions

diff --git a/lib/libm/Makefile b/lib/libm/Makefile
index ff94ecf79cf..b5c34b38115 100644
--- a/lib/libm/Makefile
+++ b/lib/libm/Makefile
@@ -1,4 +1,4 @@
-#  $OpenBSD: Makefile,v 1.120 2020/06/28 08:22:57 kettenis Exp $
+#  $OpenBSD: Makefile,v 1.121 2020/11/07 11:56:40 kettenis Exp $
 #  $NetBSD: Makefile,v 1.28 1995/11/20 22:06:19 jtc Exp $
 #
 #  @(#)Makefile 5.1beta 93/09/24 
@@ -23,7 +23,7 @@ ARCH_SRCS = e_acos.S e_asin.S e_atan2.S e_exp.S e_fmod.S e_log.S e_log10.S \
 	    invtrig.c \
 	    s_atan.S s_atanf.S s_ceil.S s_ceilf.S s_copysign.S s_copysignf.S \
 	    s_cos.S s_cosf.S s_floor.S s_floorf.S \
-	    s_ilogb.S s_ilogbf.S s_log1p.S s_log1pf.S s_logb.S s_logbf.S \
+	    s_log1p.S s_log1pf.S s_logb.S s_logbf.S \
 	    s_llrint.S s_llrintf.S s_lrint.S s_lrintf.S s_rint.S s_rintf.S\
 	    s_scalbnf.S s_significand.S s_significandf.S \
 	    s_sin.S s_sinf.S s_tan.S s_tanf.S
@@ -36,7 +36,7 @@ ARCH_SRCS = e_acos.S e_asin.S e_atan2.S e_exp.S e_fmod.S e_log.S e_log10.S \
 	    invtrig.c \
 	    s_atan.S s_atanf.S s_ceil.S s_ceilf.S s_copysign.S s_copysignf.S \
 	    s_cos.S s_cosf.S s_floor.S s_floorf.S \
-	    s_ilogb.S s_ilogbf.S s_log1p.S s_log1pf.S s_logb.S s_logbf.S \
+	    s_log1p.S s_log1pf.S s_logb.S s_logbf.S \
 	    s_llrint.S s_llrintf.S s_lrint.S s_lrintf.S \
 	    s_rint.S s_rintf.S s_scalbnf.S s_significand.S \
 	    s_significandf.S s_sin.S s_sinf.S s_tan.S s_tanf.S
diff --git a/lib/libm/arch/amd64/s_ilogb.S b/lib/libm/arch/amd64/s_ilogb.S
deleted file mode 100644
index 6ef0d469575..00000000000
--- a/lib/libm/arch/amd64/s_ilogb.S
+++ /dev/null
@@ -1,20 +0,0 @@
-/*	$OpenBSD: s_ilogb.S,v 1.5 2018/07/03 22:43:34 mortimer Exp $ */
-/*
- * Written by J.T. Conklin <jtc@NetBSD.org>.
- * Public domain.
- */
-
-#include <machine/asm.h>
-#include "abi.h"
-
-ENTRY(ilogb)
-	RETGUARD_SETUP(ilogb, r11)
-	movsd	%xmm0,-8(%rsp)
-	fldl	-8(%rsp)
-	fxtract
-	fstp	%st
-	fistpl	-8(%rsp)
-	movl	-8(%rsp),%eax
-	RETGUARD_CHECK(ilogb, r11)
-	ret
-END_STD(ilogb)
diff --git a/lib/libm/arch/amd64/s_ilogbf.S b/lib/libm/arch/amd64/s_ilogbf.S
deleted file mode 100644
index 29bf3af13bc..00000000000
--- a/lib/libm/arch/amd64/s_ilogbf.S
+++ /dev/null
@@ -1,20 +0,0 @@
-/*	$OpenBSD: s_ilogbf.S,v 1.5 2018/07/03 22:43:34 mortimer Exp $ */
-/*
- * Written by J.T. Conklin <jtc@NetBSD.org>.
- * Public domain.
- */
-
-#include <machine/asm.h>
-#include "abi.h"
-
-ENTRY(ilogbf)
-	RETGUARD_SETUP(ilogbf, r11)
-	movss	%xmm0,-4(%rsp)
-	flds	-4(%rsp)
-	fxtract
-	fstp	%st
-	fistpl	-4(%rsp)
-	movl	-4(%rsp),%eax
-	RETGUARD_CHECK(ilogbf, r11)
-	ret
-END_STD(ilogbf)
diff --git a/lib/libm/arch/i387/s_ilogb.S b/lib/libm/arch/i387/s_ilogb.S
deleted file mode 100644
index 7400ebc2b84..00000000000
--- a/lib/libm/arch/i387/s_ilogb.S
+++ /dev/null
@@ -1,23 +0,0 @@
-/*	$OpenBSD: s_ilogb.S,v 1.6 2016/09/12 19:47:02 guenther Exp $ */
-/*
- * Written by J.T. Conklin <jtc@netbsd.org>.
- * Public domain.
- */
-
-#include "DEFS.h"
-
-ENTRY(ilogb)
-	pushl	%ebp
-	movl	%esp,%ebp
-	subl	$4,%esp
-
-	fldl	8(%ebp)
-	fxtract
-	fstp	%st
-
-	fistpl	-4(%ebp)
-	movl	-4(%ebp),%eax
-
-	leave
-	ret
-END_STD(ilogb)
diff --git a/lib/libm/arch/i387/s_ilogbf.S b/lib/libm/arch/i387/s_ilogbf.S
deleted file mode 100644
index c7fd4606ad6..00000000000
--- a/lib/libm/arch/i387/s_ilogbf.S
+++ /dev/null
@@ -1,23 +0,0 @@
-/*	$OpenBSD: s_ilogbf.S,v 1.6 2016/09/12 19:47:02 guenther Exp $ */
-/*
- * Written by J.T. Conklin <jtc@netbsd.org>.
- * Public domain.
- */
-
-#include "DEFS.h"
-
-ENTRY(ilogbf)
-	pushl	%ebp
-	movl	%esp,%ebp
-	subl	$4,%esp
-
-	flds	8(%ebp)
-	fxtract
-	fstp	%st
-
-	fistpl	-4(%ebp)
-	movl	-4(%ebp),%eax
-
-	leave
-	ret
-END_STD(ilogbf)