Remove the error handling wrapper from pow

Introduce new pow symbol version that doesn't do SVID compatible error
handling.  The standard errno and fp exception based error handling is
inline in the new code and does not have significant overhead.

The wrapper is disabled for sysdeps/ieee754/dbl-64 by using empty
w_pow.c and enabled for targets with their own pow implementation or
ifunc dispatch on __ieee754_pow by including math/w_pow.c.

The compatibility symbol version still uses the wrapper with SVID error
handling around the new code.  There is no new symbol version nor
compatibility code on !LIBM_SVID_COMPAT targets (e.g. riscv).

On targets where previously powl was an alias of pow, now it points to
the compatibility symbol with the wrapper, because it still need the
SVID compatible error handling.  This affects NO_LONG_DOUBLE (e.g. arm)
and LONG_DOUBLE_COMPAT (e.g. alpha) targets as well.

The __pow_finite symbol is now an alias of pow.  Both __pow_finite and
pow set errno and thus not const functions.

The ia64 asm is changed so the compat and new symbol versions map to the
same address.

On x86_64 #include <math.h> was added before macro definitions that
may affect that header.

Tested with build-many-glibcs.py.

	* math/Versions (GLIBC_2.29): Add pow.
	* math/w_pow_compat.c (__pow_compat): Change to versioned compat
	symbol.
	* math/w_pow.c: New file.
	* sysdeps/i386/fpu/w_pow.c: New file.
	* sysdeps/ia64/fpu/e_pow.S: Add versioned symbols.
	* sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Rename to __pow
	and add necessary aliases.
	* sysdeps/ieee754/dbl-64/w_pow.c: New file.
	* sysdeps/m68k/m680x0/fpu/w_pow.c: New file.
	* sysdeps/mach/hurd/i386/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/alpha/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/arm/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/hppa/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/i386/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/ia64/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/nios2/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist: Update.
	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/sh/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Update.
	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Update.
	* sysdeps/x86_64/fpu/multiarch/e_pow-fma.c (__ieee754_pow): Rename to
	__pow.
	* sysdeps/x86_64/fpu/multiarch/e_pow-fma4.c (__ieee754_pow): Likewise.
	* sysdeps/x86_64/fpu/multiarch/e_pow.c (__ieee754_pow): Likewise.
	* sysdeps/x86_64/fpu/multiarch/w_pow.c: New file.

ChangeLog

@@ -1,3 +1,45 @@
+2018-11-21  Szabolcs Nagy  <szabolcs.nagy@arm.com>
+
+	* math/Versions (GLIBC_2.29): Add pow.
+	* math/w_pow_compat.c (__pow_compat): Change to versioned compat
+	symbol.
+	* math/w_pow.c: New file.
+	* sysdeps/i386/fpu/w_pow.c: New file.
+	* sysdeps/ia64/fpu/e_pow.S: Add versioned symbols.
+	* sysdeps/ieee754/dbl-64/e_pow.c (__ieee754_pow): Rename to __pow
+	and add necessary aliases.
+	* sysdeps/ieee754/dbl-64/w_pow.c: New file.
+	* sysdeps/m68k/m680x0/fpu/w_pow.c: New file.
+	* sysdeps/mach/hurd/i386/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/aarch64/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/alpha/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/arm/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/hppa/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/i386/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/ia64/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/microblaze/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/mips/mips32/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/mips/mips64/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/nios2/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist: Update.
+	* sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/sh/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/x86_64/64/libm.abilist: Update.
+	* sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist: Update.
+	* sysdeps/x86_64/fpu/multiarch/e_pow-fma.c (__ieee754_pow): Rename to
+	__pow.
+	* sysdeps/x86_64/fpu/multiarch/e_pow-fma4.c (__ieee754_pow): Likewise.
+	* sysdeps/x86_64/fpu/multiarch/e_pow.c (__ieee754_pow): Likewise.
+	* sysdeps/x86_64/fpu/multiarch/w_pow.c: New file.
+
 2018-11-21  Szabolcs Nagy  <szabolcs.nagy@arm.com>
 
 	* math/Versions (GLIBC_2.29): Add log2.

math/Versions

@@ -577,6 +577,6 @@ libm {
   }
   GLIBC_2.29 {
     # No SVID compatible error handling.
-    exp; exp2; log; log2;
+    exp; exp2; log; log2; pow;
   }
 }

math/w_pow.c

@@ -0,0 +1,8 @@
+#include <math-type-macros-double.h>
+#undef __USE_WRAPPER_TEMPLATE
+#define __USE_WRAPPER_TEMPLATE 1
+#undef declare_mgen_alias
+#define declare_mgen_alias(a, b)
+#include <w_pow_template.c>
+versioned_symbol (libm, __pow, pow, GLIBC_2_29);
+libm_alias_double_other (__pow, pow)

math/w_pow_compat.c

@@ -22,10 +22,12 @@
 #include <libm-alias-double.h>
 
 
-#if LIBM_SVID_COMPAT
+#if LIBM_SVID_COMPAT && (SHLIB_COMPAT (libm, GLIBC_2_0, GLIBC_2_29) \
+			 || defined NO_LONG_DOUBLE \
+			 || defined LONG_DOUBLE_COMPAT)
 /* wrapper pow */
 double
-__pow (double x, double y)
+__pow_compat (double x, double y)
 {
   double z = __ieee754_pow (x, y);
   if (__glibc_unlikely (!isfinite (z)))
@@ -60,5 +62,17 @@ __pow (double x, double y)
 
   return z;
 }
-libm_alias_double (__pow, pow)
+# if SHLIB_COMPAT (libm, GLIBC_2_0, GLIBC_2_29)
+compat_symbol (libm, __pow_compat, pow, GLIBC_2_0);
+# endif
+# ifdef NO_LONG_DOUBLE
+weak_alias (__pow_compat, powl)
+# endif
+# ifdef LONG_DOUBLE_COMPAT
+/* Work around gas bug "multiple versions for symbol".  */
+weak_alias (__pow_compat, __pow_compat_alias)
+
+LONG_DOUBLE_COMPAT_CHOOSE_libm_powl (
+  compat_symbol (libm, __pow_compat_alias, powl, FIRST_VERSION_libm_powl), );
+# endif
 #endif

sysdeps/i386/fpu/w_pow.c

@@ -0,0 +1 @@
+#include <sysdeps/../math/w_pow.c>

sysdeps/ia64/fpu/e_pow.S

@@ -910,7 +910,7 @@ data8 0xEAC0C6E7DD24392F , 0x00003FFF
 LOCAL_OBJECT_END(pow_tbl2)
 
 .section .text
-GLOBAL_LIBM_ENTRY(pow)
+WEAK_LIBM_ENTRY(pow)
 
 // Get exponent of x.  Will be used to calculate K.
 { .mfi
@@ -2233,8 +2233,14 @@ POW_OVER_UNDER_ERROR:
 }
 ;;
 
-GLOBAL_LIBM_END(pow)
+WEAK_LIBM_END(pow)
-libm_alias_double_other (pow, pow)
+libm_alias_double_other (__pow, pow)
+#ifdef SHARED
+.symver pow,pow@@GLIBC_2.29
+.weak __pow_compat
+.set __pow_compat,__pow
+.symver __pow_compat,pow@GLIBC_2.2
+#endif
 
 
 LOCAL_LIBM_ENTRY(__libm_error_region)

sysdeps/ieee754/dbl-64/e_pow.c

@@ -20,6 +20,9 @@
 #include <stdint.h>
 #include <math-barriers.h>
 #include <math-narrow-eval.h>
+#include <math-svid-compat.h>
+#include <shlib-compat.h>
+#include <libm-alias-double.h>
 #include "math_config.h"
 
 /*
@@ -276,7 +279,7 @@ zeroinfnan (uint64_t i)
 
 double
 SECTION
-__ieee754_pow (double x, double y)
+__pow (double x, double y)
 {
   uint32_t sign_bias = 0;
   uint64_t ix, iy;
@@ -375,6 +378,13 @@ __ieee754_pow (double x, double y)
 #endif
   return exp_inline (ehi, elo, sign_bias);
 }
-#ifndef __ieee754_pow
+#ifndef __pow
-strong_alias (__ieee754_pow, __pow_finite)
+strong_alias (__pow, __ieee754_pow)
+strong_alias (__pow, __pow_finite)
+# if LIBM_SVID_COMPAT
+versioned_symbol (libm, __pow, pow, GLIBC_2_29);
+libm_alias_double_other (__pow, pow)
+# else
+libm_alias_double (__pow, pow)
+# endif
 #endif

sysdeps/ieee754/dbl-64/w_pow.c

@@ -0,0 +1 @@
+/* Not needed.  */

sysdeps/m68k/m680x0/fpu/w_pow.c

@@ -0,0 +1 @@
+#include <sysdeps/../math/w_pow.c>

sysdeps/mach/hurd/i386/libm.abilist

@@ -1072,3 +1072,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/aarch64/libm.abilist

@@ -1036,3 +1036,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/alpha/libm.abilist

@@ -1047,6 +1047,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.3.4 __c1_cabsf F
 GLIBC_2.3.4 __c1_cacosf F
 GLIBC_2.3.4 __c1_cacoshf F

sysdeps/unix/sysv/linux/arm/libm.abilist

@@ -457,6 +457,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 _LIB_VERSION D 0x4
 GLIBC_2.4 __clog10 F
 GLIBC_2.4 __clog10f F

sysdeps/unix/sysv/linux/hppa/libm.abilist

@@ -768,4 +768,5 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 exp2l F

sysdeps/unix/sysv/linux/i386/libm.abilist

@@ -1079,3 +1079,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/ia64/libm.abilist

@@ -1009,3 +1009,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/m68k/coldfire/libm.abilist

@@ -457,6 +457,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 _LIB_VERSION D 0x4
 GLIBC_2.4 __clog10 F
 GLIBC_2.4 __clog10f F

sysdeps/unix/sysv/linux/m68k/m680x0/libm.abilist

@@ -808,3 +808,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/microblaze/libm.abilist

@@ -769,3 +769,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/mips/mips32/libm.abilist

@@ -768,4 +768,5 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 exp2l F

sysdeps/unix/sysv/linux/mips/mips64/libm.abilist

@@ -1036,3 +1036,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/nios2/libm.abilist

@@ -769,3 +769,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/powerpc/powerpc32/fpu/libm.abilist

@@ -814,6 +814,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
 GLIBC_2.4 __fpclassifyl F

sysdeps/unix/sysv/linux/powerpc/powerpc32/nofpu/libm.abilist

@@ -813,6 +813,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
 GLIBC_2.4 __fpclassifyl F

sysdeps/unix/sysv/linux/powerpc/powerpc64/libm-le.abilist

@@ -1080,3 +1080,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/powerpc/powerpc64/libm.abilist

@@ -492,6 +492,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.3 _LIB_VERSION D 0x4
 GLIBC_2.3 __clog10 F
 GLIBC_2.3 __clog10f F

sysdeps/unix/sysv/linux/s390/s390-32/libm.abilist

@@ -1037,6 +1037,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
 GLIBC_2.4 __fpclassifyl F

sysdeps/unix/sysv/linux/s390/s390-64/libm.abilist

@@ -1037,6 +1037,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
 GLIBC_2.4 __fpclassifyl F

sysdeps/unix/sysv/linux/sh/libm.abilist

@@ -768,4 +768,5 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 exp2l F

sysdeps/unix/sysv/linux/sparc/sparc32/libm.abilist

@@ -1044,6 +1044,7 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F
 GLIBC_2.4 __clog10l F
 GLIBC_2.4 __finitel F
 GLIBC_2.4 __fpclassifyl F

sysdeps/unix/sysv/linux/sparc/sparc64/libm.abilist

@@ -1036,3 +1036,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/x86_64/64/libm.abilist

@@ -1070,3 +1070,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/unix/sysv/linux/x86_64/x32/libm.abilist

@@ -1070,3 +1070,4 @@ GLIBC_2.29 exp F
 GLIBC_2.29 exp2 F
 GLIBC_2.29 log F
 GLIBC_2.29 log2 F
+GLIBC_2.29 pow F

sysdeps/x86_64/fpu/multiarch/e_pow-fma.c

@@ -1,5 +1,5 @@
-#define __ieee754_pow __ieee754_pow_fma
+#include <math.h>
-#define __exp1 __exp1_fma
+#define __pow __ieee754_pow_fma
 #define SECTION __attribute__ ((section (".text.fma")))
 
 #include <sysdeps/ieee754/dbl-64/e_pow.c>

sysdeps/x86_64/fpu/multiarch/e_pow-fma4.c

@@ -1,5 +1,5 @@
-#define __ieee754_pow __ieee754_pow_fma4
+#include <math.h>
-#define __exp1 __exp1_fma4
+#define __pow __ieee754_pow_fma4
 #define SECTION __attribute__ ((section (".text.fma4")))
 
 #include <sysdeps/ieee754/dbl-64/e_pow.c>

sysdeps/x86_64/fpu/multiarch/e_pow.c

@@ -16,6 +16,8 @@
    License along with the GNU C Library; if not, see
    <http://www.gnu.org/licenses/>.  */
 
+#include <math.h>
+
 extern double __redirect_ieee754_pow (double, double);
 
 #define SYMBOL_NAME ieee754_pow
@@ -25,5 +27,5 @@ libc_ifunc_redirected (__redirect_ieee754_pow,
 		       __ieee754_pow, IFUNC_SELECTOR ());
 strong_alias (__ieee754_pow, __pow_finite)
 
-#define __ieee754_pow __ieee754_pow_sse2
+#define __pow __ieee754_pow_sse2
 #include <sysdeps/ieee754/dbl-64/e_pow.c>

sysdeps/x86_64/fpu/multiarch/w_pow.c

@@ -0,0 +1 @@
+#include <sysdeps/../math/w_pow.c>