Fix sin, cos, tan in non-default rounding modes (bug 3976)
Andreas Jaeger
aj@suse.com
Fri Mar 2 18:15:00 GMT 2012
On 03/02/2012 06:39 PM, Joseph S. Myers wrote:
> Similar to the patch for exp, this patch fixes problems with sin, cos
> and tan producing wild results in non-default rounding modes by making
> them save and restore the rounding mode and do computations in
> round-to-nearest.
>
> Tested on x86_64 and x86 and ULPs updated based on those tests.
>
> 2012-03-02 Joseph Myers<joseph@codesourcery.com>
>
> [BZ #3976]
> * sysdeps/ieee754/dbl-64/s_sin.c: Include<fenv.h>
> (__sin): Save and restore rounding mode and use round-to-nearest
> for all computations.
> (__cos): Save and restore rounding mode and use round-to-nearest
> for all computations.
> * sysdeps/ieee754/dbl-64/s_tan.c: Include "math_private.h" and
> <fenv.h>.
> (tan): Save and restore rounding mode and use round-to-nearest for
> all computations.
> * math/libm-test.inc (cos_test_tonearest): New function.
> (cos_test_towardzero): Likewise.
> (cos_test_downward): Likewise.
> (cos_test_upward): Likewise.
> (sin_test_tonearest): Likewise.
> (sin_test_towardzero): Likewise.
> (sin_test_downward): Likewise.
> (sin_test_upward): Likewise.
> (tan_test_tonearest): Likewise.
> (tan_test_towardzero): Likewise.
> (tan_test_downward): Likewise.
> (tan_test_upward): Likewise.
> (main): Call the new functions.
> * sysdeps/i386/fpu/libm-test-ulps: Update.
> * sysdeps/x86_64/fpu/libm-test-ulps: Likewise.
> [...]
thanks, this looks fine, I just have a few suggestions for minor nits below.
> diff --git a/sysdeps/ieee754/dbl-64/s_sin.c b/sysdeps/ieee754/dbl-64/s_sin.c
> index 5b79854..32ba66d 100644
> --- a/sysdeps/ieee754/dbl-64/s_sin.c
> +++ b/sysdeps/ieee754/dbl-64/s_sin.c
> @@ -53,6 +53,7 @@
> #include "usncs.h"
> #include "MathLib.h"
> #include "math_private.h"
> +#include<fenv.h>
>
> #ifndef SECTION
> # define SECTION
> @@ -107,12 +108,16 @@ __sin(double x){
> #if 0
> int4 nn;
> #endif
> + fenv_t env;
> + double retval = 0;
> +
> + libc_feholdexcept_setround (&env, FE_TONEAREST);
>
> u.x = x;
> m = u.i[HIGH_HALF];
> k = 0x7fffffff&m; /* no sign */
> if (k< 0x3e500000) /* if x->0 =>sin(x)=x */
> - return x;
> + { retval = x; goto ret; }
> /*---------------------------- 2^-26< |x|< 0.25 ----------------------*/
> else if (k< 0x3fd00000){
> xx = x*x;
> @@ -120,7 +125,8 @@ __sin(double x){
> t = ((((s5.x*xx + s4.x)*xx + s3.x)*xx + s2.x)*xx + s1.x)*(xx*x);
> res = x+t;
> cor = (x-res)+t;
> - return (res == res + 1.07*cor)? res : slow(x);
> + retval = (res == res + 1.07*cor)? res : slow(x);
> + goto ret;
> } /* else if (k< 0x3fd00000) */
> /*---------------------------- 0.25<|x|< 0.855469---------------------- */
> else if (k< 0x3feb6000) {
> @@ -137,7 +143,8 @@ __sin(double x){
> cor=(ssn+s*ccs-sn*c)+cs*s;
> res=sn+cor;
> cor=(sn-res)+cor;
> - return (res==res+1.096*cor)? res : slow1(x);
> + retval = (res==res+1.096*cor)? res : slow1(x);
> + goto ret;
> } /* else if (k< 0x3feb6000) */
>
> /*----------------------- 0.855469<|x|<2.426265 ----------------------*/
> @@ -163,7 +170,8 @@ __sin(double x){
> cor=(ccs-s*ssn-cs*c)-sn*s;
> res=cs+cor;
> cor=(cs-res)+cor;
> - return (res==res+1.020*cor)? ((m>0)?res:-res) : slow2(x);
> + retval = (res==res+1.020*cor)? ((m>0)?res:-res) : slow2(x);
> + goto ret;
> } /* else if (k< 0x400368fd) */
>
> /*-------------------------- 2.426265<|x|< 105414350 ----------------------*/
> @@ -189,7 +197,8 @@ __sin(double x){
> res = a+t;
> cor = (a-res)+t;
> cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps;
> - return (res == res + cor)? res : sloww(a,da,x);
> + retval = (res == res + cor)? res : sloww(a,da,x);
> + goto ret;
> }
> else {
> if (a>0)
> @@ -210,7 +219,8 @@ __sin(double x){
> res=sn+cor;
> cor=(sn-res)+cor;
> cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps;
> - return (res==res+cor)? ((m)?res:-res) : sloww1(a,da,x);
> + retval = (res==res+cor)? ((m)?res:-res) : sloww1(a,da,x);
> + goto ret;
> }
> break;
>
> @@ -232,7 +242,8 @@ __sin(double x){
> res=cs+cor;
> cor=(cs-res)+cor;
> cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps;
> - return (res==res+cor)? ((n&2)?-res:res) : sloww2(a,da,x,n);
> + retval = (res==res+cor)? ((n&2)?-res:res) : sloww2(a,da,x,n);
> + goto ret;
>
> break;
>
> @@ -268,7 +279,8 @@ __sin(double x){
> res = a+t;
> cor = (a-res)+t;
> cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps;
> - return (res == res + cor)? res : bsloww(a,da,x,n);
> + retval = (res == res + cor)? res : bsloww(a,da,x,n);
> + goto ret;
> }
> else {
> if (a>0) {m=1;t=a;db=da;}
> @@ -287,7 +299,8 @@ __sin(double x){
> res=sn+cor;
> cor=(sn-res)+cor;
> cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps;
> - return (res==res+cor)? ((m)?res:-res) : bsloww1(a,da,x,n);
> + retval = (res==res+cor)? ((m)?res:-res) : bsloww1(a,da,x,n);
> + goto ret;
> }
> break;
>
> @@ -309,7 +322,8 @@ __sin(double x){
> res=cs+cor;
> cor=(cs-res)+cor;
> cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps;
> - return (res==res+cor)? ((n&2)?-res:res) : bsloww2(a,da,x,n);
> + retval = (res==res+cor)? ((n&2)?-res:res) : bsloww2(a,da,x,n);
> + goto ret;
>
> break;
>
> @@ -323,17 +337,20 @@ __sin(double x){
> n = __branred(x,&a,&da);
> switch (n) {
> case 0:
> - if (a*a< 0.01588) return bsloww(a,da,x,n);
> - else return bsloww1(a,da,x,n);
> + if (a*a< 0.01588) retval = bsloww(a,da,x,n);
> + else retval = bsloww1(a,da,x,n);
> + goto ret;
> break;
> case 2:
> - if (a*a< 0.01588) return bsloww(-a,-da,x,n);
> - else return bsloww1(-a,-da,x,n);
> + if (a*a< 0.01588) retval = bsloww(-a,-da,x,n);
> + else retval = bsloww1(-a,-da,x,n);
> + goto ret;
> break;
>
> case 1:
> case 3:
> - return bsloww2(a,da,x,n);
> + retval = bsloww2(a,da,x,n);
> + goto ret;
> break;
> }
>
> @@ -343,9 +360,13 @@ __sin(double x){
> else {
> if (k == 0x7ff00000&& u.i[LOW_HALF] == 0)
> __set_errno (EDOM);
> - return x / x;
> + retval = x / x;
> + goto ret;
I suggest to remove the goto ret.
> }
> - return 0; /* unreachable */
> +
> + ret:
> + libc_feupdateenv (&env);
> + return retval;
> }
>
>
> @@ -362,11 +383,16 @@ __cos(double x)
> mynumber u,v;
> int4 k,m,n;
>
> + fenv_t env;
> + double retval = 0;
> +
> + libc_feholdexcept_setround (&env, FE_TONEAREST);
> +
> u.x = x;
> m = u.i[HIGH_HALF];
> k = 0x7fffffff&m;
>
> - if (k< 0x3e400000 ) return 1.0; /* |x|<2^-27 => cos(x)=1 */
> + if (k< 0x3e400000 ) { retval = 1.0; goto ret; } /* |x|<2^-27 => cos(x)=1 */
>
> else if (k< 0x3feb6000 ) {/* 2^-27< |x|< 0.855469 */
> y=ABS(x);
> @@ -383,7 +409,8 @@ __cos(double x)
> cor=(ccs-s*ssn-cs*c)-sn*s;
> res=cs+cor;
> cor=(cs-res)+cor;
> - return (res==res+1.020*cor)? res : cslow2(x);
> + retval = (res==res+1.020*cor)? res : cslow2(x);
> + goto ret;
>
> } /* else if (k< 0x3feb6000) */
>
> @@ -397,7 +424,8 @@ __cos(double x)
> res = a+t;
> cor = (a-res)+t;
> cor = (cor>0)? 1.02*cor+1.0e-31 : 1.02*cor -1.0e-31;
> - return (res == res + cor)? res : csloww(a,da,x);
> + retval = (res == res + cor)? res : csloww(a,da,x);
> + goto ret;
> }
> else {
> if (a>0) {m=1;t=a;db=da;}
> @@ -416,7 +444,8 @@ __cos(double x)
> res=sn+cor;
> cor=(sn-res)+cor;
> cor = (cor>0)? 1.035*cor+1.0e-31 : 1.035*cor-1.0e-31;
> - return (res==res+cor)? ((m)?res:-res) : csloww1(a,da,x);
> + retval = (res==res+cor)? ((m)?res:-res) : csloww1(a,da,x);
> + goto ret;
> }
>
> } /* else if (k< 0x400368fd) */
> @@ -443,7 +472,8 @@ __cos(double x)
> res = a+t;
> cor = (a-res)+t;
> cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps;
> - return (res == res + cor)? res : csloww(a,da,x);
> + retval = (res == res + cor)? res : csloww(a,da,x);
> + goto ret;
> }
> else {
> if (a>0) {m=1;t=a;db=da;}
> @@ -462,7 +492,8 @@ __cos(double x)
> res=sn+cor;
> cor=(sn-res)+cor;
> cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps;
> - return (res==res+cor)? ((m)?res:-res) : csloww1(a,da,x);
> + retval = (res==res+cor)? ((m)?res:-res) : csloww1(a,da,x);
> + goto ret;
> }
> break;
>
> @@ -483,7 +514,8 @@ __cos(double x)
> res=cs+cor;
> cor=(cs-res)+cor;
> cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps;
> - return (res==res+cor)? ((n)?-res:res) : csloww2(a,da,x,n);
> + retval = (res==res+cor)? ((n)?-res:res) : csloww2(a,da,x,n);
> + goto ret;
>
> break;
>
> @@ -518,7 +550,8 @@ __cos(double x)
> res = a+t;
> cor = (a-res)+t;
> cor = (cor>0)? 1.02*cor+eps : 1.02*cor -eps;
> - return (res == res + cor)? res : bsloww(a,da,x,n);
> + retval = (res == res + cor)? res : bsloww(a,da,x,n);
> + goto ret;
> }
> else {
> if (a>0) {m=1;t=a;db=da;}
> @@ -537,7 +570,8 @@ __cos(double x)
> res=sn+cor;
> cor=(sn-res)+cor;
> cor = (cor>0)? 1.035*cor+eps : 1.035*cor-eps;
> - return (res==res+cor)? ((m)?res:-res) : bsloww1(a,da,x,n);
> + retval = (res==res+cor)? ((m)?res:-res) : bsloww1(a,da,x,n);
> + goto ret;
> }
> break;
>
> @@ -558,7 +592,8 @@ __cos(double x)
> res=cs+cor;
> cor=(cs-res)+cor;
> cor = (cor>0)? 1.025*cor+eps : 1.025*cor-eps;
> - return (res==res+cor)? ((n)?-res:res) : bsloww2(a,da,x,n);
> + retval = (res==res+cor)? ((n)?-res:res) : bsloww2(a,da,x,n);
> + goto ret;
> break;
>
> }
> @@ -570,17 +605,20 @@ __cos(double x)
> n = __branred(x,&a,&da);
> switch (n) {
> case 1:
> - if (a*a< 0.01588) return bsloww(-a,-da,x,n);
> - else return bsloww1(-a,-da,x,n);
> + if (a*a< 0.01588) retval = bsloww(-a,-da,x,n);
> + else retval = bsloww1(-a,-da,x,n);
> + goto ret;
> break;
> case 3:
> - if (a*a< 0.01588) return bsloww(a,da,x,n);
> - else return bsloww1(a,da,x,n);
> + if (a*a< 0.01588) retval = bsloww(a,da,x,n);
> + else retval = bsloww1(a,da,x,n);
> + goto ret;
> break;
>
> case 0:
> case 2:
> - return bsloww2(a,da,x,n);
> + retval = bsloww2(a,da,x,n);
> + goto ret;
> break;
> }
>
> @@ -592,10 +630,13 @@ __cos(double x)
> else {
> if (k == 0x7ff00000&& u.i[LOW_HALF] == 0)
> __set_errno (EDOM);
> - return x / x; /* |x|> 2^1024 */
> + retval = x / x; /* |x|> 2^1024 */
> + goto ret;
I suggest to omit the goto ret.
> }
> - return 0;
>
> + ret:
> + libc_feupdateenv (&env);
> + return retval;
> }
>
> /************************************************************************/
> diff --git a/sysdeps/ieee754/dbl-64/s_tan.c b/sysdeps/ieee754/dbl-64/s_tan.c
> index 962a4eb..2c26756 100644
> --- a/sysdeps/ieee754/dbl-64/s_tan.c
> +++ b/sysdeps/ieee754/dbl-64/s_tan.c
> @@ -39,6 +39,8 @@
> #include "mpa.h"
> #include "MathLib.h"
> #include "math.h"
> +#include "math_private.h"
> +#include<fenv.h>
>
> #ifndef SECTION
> # define SECTION
> @@ -66,21 +68,27 @@ tan(double x) {
> mp_no mpy;
> #endif
>
> + fenv_t env;
> + double retval;
> +
> int __branred(double, double *, double *);
> int __mpranred(double, mp_no *, int);
>
> + libc_feholdexcept_setround (&env, FE_TONEAREST);
> +
> /* x=+-INF, x=NaN */
> num.d = x; ux = num.i[HIGH_HALF];
> if ((ux&0x7ff00000)==0x7ff00000) {
> if ((ux&0x7fffffff)==0x7ff00000)
> __set_errno (EDOM);
> - return x-x;
> + retval = x-x;
> + goto ret;
> }
>
> w=(x<ZERO) ? -x : x;
>
> /* (I) The case abs(x)<= 1.259e-8 */
> - if (w<=g1.d) return x;
> + if (w<=g1.d) { retval = x; goto ret; }
>
> /* (II) The case 1.259e-8< abs(x)<= 0.0608 */
> if (w<=g2.d) {
> @@ -88,7 +96,7 @@ tan(double x) {
> /* First stage */
> x2 = x*x;
> t2 = x*x2*(d3.d+x2*(d5.d+x2*(d7.d+x2*(d9.d+x2*d11.d))));
> - if ((y=x+(t2-u1.d*t2)) == x+(t2+u1.d*t2)) return y;
> + if ((y=x+(t2-u1.d*t2)) == x+(t2+u1.d*t2)) { retval = y; goto ret; }
>
> /* Second stage */
> c1 = x2*(a15.d+x2*(a17.d+x2*(a19.d+x2*(a21.d+x2*(a23.d+x2*(a25.d+
> @@ -108,8 +116,9 @@ tan(double x) {
> MUL2(x2,xx2,c2,cc2,c1,cc1,t1,t2,t3,t4,t5,t6,t7,t8)
> MUL2(x ,zero.d,c1,cc1,c2,cc2,t1,t2,t3,t4,t5,t6,t7,t8)
> ADD2(x ,zero.d,c2,cc2,c1,cc1,t1,t2)
> - if ((y=c1+(cc1-u2.d*c1)) == c1+(cc1+u2.d*c1)) return y;
> - return tanMp(x);
> + if ((y=c1+(cc1-u2.d*c1)) == c1+(cc1+u2.d*c1)) { retval = y; goto ret; }
> + retval = tanMp(x);
> + goto ret;
> }
>
> /* (III) The case 0.0608< abs(x)<= 0.787 */
> @@ -120,10 +129,10 @@ tan(double x) {
> z = w-xfg[i][0].d; z2 = z*z; s = (x<ZERO) ? MONE : ONE;
> pz = z+z*z2*(e0.d+z2*e1.d);
> fi = xfg[i][1].d; gi = xfg[i][2].d; t2 = pz*(gi+fi)/(gi-pz);
> - if ((y=fi+(t2-fi*u3.d))==fi+(t2+fi*u3.d)) return (s*y);
> + if ((y=fi+(t2-fi*u3.d))==fi+(t2+fi*u3.d)) { retval = (s*y); goto ret; }
> t3 = (t2<ZERO) ? -t2 : t2;
> t4 = fi*ua3.d+t3*ub3.d;
> - if ((y=fi+(t2-t4))==fi+(t2+t4)) return (s*y);
> + if ((y=fi+(t2-t4))==fi+(t2+t4)) { retval = (s*y); goto ret; }
>
> /* Second stage */
> ffi = xfg[i][3].d;
> @@ -141,8 +150,9 @@ tan(double x) {
> SUB2(one.d,zero.d,c3,cc3,c1,cc1,t1,t2)
> DIV2(c2,cc2,c1,cc1,c3,cc3,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
>
> - if ((y=c3+(cc3-u4.d*c3))==c3+(cc3+u4.d*c3)) return (s*y);
> - return tanMp(x);
> + if ((y=c3+(cc3-u4.d*c3))==c3+(cc3+u4.d*c3)) { retval = (s*y); goto ret; }
> + retval = tanMp(x);
> + goto ret;
> }
>
> /* (---) The case 0.787< abs(x)<= 25 */
> @@ -160,7 +170,7 @@ tan(double x) {
> else {ya= a; yya= da; sy= ONE;}
>
> /* (IV),(V) The case 0.787< abs(x)<= 25, abs(y)<= 1e-7 */
> - if (ya<=gy1.d) return tanMp(x);
> + if (ya<=gy1.d) { retval = tanMp(x); goto ret; }
>
> /* (VI) The case 0.787< abs(x)<= 25, 1e-7< abs(y)<= 0.0608 */
> if (ya<=gy2.d) {
> @@ -170,10 +180,10 @@ tan(double x) {
> /* First stage -cot */
> EADD(a,t2,b,db)
> DIV2(one.d,zero.d,b,db,c,dc,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c+(dc-u6.d*c))==c+(dc+u6.d*c)) return (-y); }
> + if ((y=c+(dc-u6.d*c))==c+(dc+u6.d*c)) { retval = (-y); goto ret; } }
> else {
> /* First stage tan */
> - if ((y=a+(t2-u5.d*a))==a+(t2+u5.d*a)) return y; }
> + if ((y=a+(t2-u5.d*a))==a+(t2+u5.d*a)) { retval = y; goto ret; } }
> /* Second stage */
> /* Range reduction by algorithm ii */
> t = (x*hpinv.d + toint.d);
> @@ -211,11 +221,12 @@ tan(double x) {
> if (n) {
> /* Second stage -cot */
> DIV2(one.d,zero.d,c1,cc1,c2,cc2,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c2+(cc2-u8.d*c2)) == c2+(cc2+u8.d*c2)) return (-y); }
> + if ((y=c2+(cc2-u8.d*c2)) == c2+(cc2+u8.d*c2)) { retval = (-y); goto ret; } }
> else {
> /* Second stage tan */
> - if ((y=c1+(cc1-u7.d*c1)) == c1+(cc1+u7.d*c1)) return y; }
> - return tanMp(x);
> + if ((y=c1+(cc1-u7.d*c1)) == c1+(cc1+u7.d*c1)) { retval = y; goto ret; } }
> + retval = tanMp(x);
> + goto ret;
> }
>
> /* (VII) The case 0.787< abs(x)<= 25, 0.0608< abs(y)<= 0.787 */
> @@ -229,17 +240,17 @@ tan(double x) {
> if (n) {
> /* -cot */
> t2 = pz*(fi+gi)/(fi+pz);
> - if ((y=gi-(t2-gi*u10.d))==gi-(t2+gi*u10.d)) return (-sy*y);
> + if ((y=gi-(t2-gi*u10.d))==gi-(t2+gi*u10.d)) { retval = (-sy*y); goto ret; }
> t3 = (t2<ZERO) ? -t2 : t2;
> t4 = gi*ua10.d+t3*ub10.d;
> - if ((y=gi-(t2-t4))==gi-(t2+t4)) return (-sy*y); }
> + if ((y=gi-(t2-t4))==gi-(t2+t4)) { retval = (-sy*y); goto ret; } }
> else {
> /* tan */
> t2 = pz*(gi+fi)/(gi-pz);
> - if ((y=fi+(t2-fi*u9.d))==fi+(t2+fi*u9.d)) return (sy*y);
> + if ((y=fi+(t2-fi*u9.d))==fi+(t2+fi*u9.d)) { retval = (sy*y); goto ret; }
> t3 = (t2<ZERO) ? -t2 : t2;
> t4 = fi*ua9.d+t3*ub9.d;
> - if ((y=fi+(t2-t4))==fi+(t2+t4)) return (sy*y); }
> + if ((y=fi+(t2-t4))==fi+(t2+t4)) { retval = (sy*y); goto ret; } }
>
> /* Second stage */
> ffi = xfg[i][3].d;
> @@ -260,13 +271,14 @@ tan(double x) {
> if (n) {
> /* -cot */
> DIV2(c1,cc1,c2,cc2,c3,cc3,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c3+(cc3-u12.d*c3))==c3+(cc3+u12.d*c3)) return (-sy*y); }
> + if ((y=c3+(cc3-u12.d*c3))==c3+(cc3+u12.d*c3)) { retval = (-sy*y); goto ret; } }
> else {
> /* tan */
> DIV2(c2,cc2,c1,cc1,c3,cc3,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c3+(cc3-u11.d*c3))==c3+(cc3+u11.d*c3)) return (sy*y); }
> + if ((y=c3+(cc3-u11.d*c3))==c3+(cc3+u11.d*c3)) { retval = (sy*y); goto ret; } }
>
> - return tanMp(x);
> + retval = tanMp(x);
> + goto ret;
> }
>
> /* (---) The case 25< abs(x)<= 1e8 */
> @@ -288,7 +300,7 @@ tan(double x) {
> else {ya= a; yya= da; sy= ONE;}
>
> /* (+++) The case 25< abs(x)<= 1e8, abs(y)<= 1e-7 */
> - if (ya<=gy1.d) return tanMp(x);
> + if (ya<=gy1.d) { retval = tanMp(x); goto ret; }
>
> /* (VIII) The case 25< abs(x)<= 1e8, 1e-7< abs(y)<= 0.0608 */
> if (ya<=gy2.d) {
> @@ -298,10 +310,10 @@ tan(double x) {
> /* First stage -cot */
> EADD(a,t2,b,db)
> DIV2(one.d,zero.d,b,db,c,dc,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c+(dc-u14.d*c))==c+(dc+u14.d*c)) return (-y); }
> + if ((y=c+(dc-u14.d*c))==c+(dc+u14.d*c)) { retval = (-y); goto ret; } }
> else {
> /* First stage tan */
> - if ((y=a+(t2-u13.d*a))==a+(t2+u13.d*a)) return y; }
> + if ((y=a+(t2-u13.d*a))==a+(t2+u13.d*a)) { retval = y; goto ret; } }
>
> /* Second stage */
> MUL2(a,da,a,da,x2,xx2,t1,t2,t3,t4,t5,t6,t7,t8)
> @@ -325,11 +337,12 @@ tan(double x) {
> if (n) {
> /* Second stage -cot */
> DIV2(one.d,zero.d,c1,cc1,c2,cc2,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c2+(cc2-u16.d*c2)) == c2+(cc2+u16.d*c2)) return (-y); }
> + if ((y=c2+(cc2-u16.d*c2)) == c2+(cc2+u16.d*c2)) { retval = (-y); goto ret; } }
> else {
> /* Second stage tan */
> - if ((y=c1+(cc1-u15.d*c1)) == c1+(cc1+u15.d*c1)) return (y); }
> - return tanMp(x);
> + if ((y=c1+(cc1-u15.d*c1)) == c1+(cc1+u15.d*c1)) { retval = (y); goto ret; } }
> + retval = tanMp(x);
> + goto ret;
> }
>
> /* (IX) The case 25< abs(x)<= 1e8, 0.0608< abs(y)<= 0.787 */
> @@ -342,17 +355,17 @@ tan(double x) {
> if (n) {
> /* -cot */
> t2 = pz*(fi+gi)/(fi+pz);
> - if ((y=gi-(t2-gi*u18.d))==gi-(t2+gi*u18.d)) return (-sy*y);
> + if ((y=gi-(t2-gi*u18.d))==gi-(t2+gi*u18.d)) { retval = (-sy*y); goto ret; }
> t3 = (t2<ZERO) ? -t2 : t2;
> t4 = gi*ua18.d+t3*ub18.d;
> - if ((y=gi-(t2-t4))==gi-(t2+t4)) return (-sy*y); }
> + if ((y=gi-(t2-t4))==gi-(t2+t4)) { retval = (-sy*y); goto ret; } }
> else {
> /* tan */
> t2 = pz*(gi+fi)/(gi-pz);
> - if ((y=fi+(t2-fi*u17.d))==fi+(t2+fi*u17.d)) return (sy*y);
> + if ((y=fi+(t2-fi*u17.d))==fi+(t2+fi*u17.d)) { retval = (sy*y); goto ret; }
> t3 = (t2<ZERO) ? -t2 : t2;
> t4 = fi*ua17.d+t3*ub17.d;
> - if ((y=fi+(t2-t4))==fi+(t2+t4)) return (sy*y); }
> + if ((y=fi+(t2-t4))==fi+(t2+t4)) { retval = (sy*y); goto ret; } }
>
> /* Second stage */
> ffi = xfg[i][3].d;
> @@ -373,12 +386,13 @@ tan(double x) {
> if (n) {
> /* -cot */
> DIV2(c1,cc1,c2,cc2,c3,cc3,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c3+(cc3-u20.d*c3))==c3+(cc3+u20.d*c3)) return (-sy*y); }
> + if ((y=c3+(cc3-u20.d*c3))==c3+(cc3+u20.d*c3)) { retval = (-sy*y); goto ret; } }
> else {
> /* tan */
> DIV2(c2,cc2,c1,cc1,c3,cc3,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c3+(cc3-u19.d*c3))==c3+(cc3+u19.d*c3)) return (sy*y); }
> - return tanMp(x);
> + if ((y=c3+(cc3-u19.d*c3))==c3+(cc3+u19.d*c3)) { retval = (sy*y); goto ret; } }
> + retval = tanMp(x);
> + goto ret;
> }
>
> /* (---) The case 1e8< abs(x)< 2**1024 */
> @@ -389,7 +403,7 @@ tan(double x) {
> else {ya= a; yya= da; sy= ONE;}
>
> /* (+++) The case 1e8< abs(x)< 2**1024, abs(y)<= 1e-7 */
> - if (ya<=gy1.d) return tanMp(x);
> + if (ya<=gy1.d) { retval = tanMp(x); goto ret; }
>
> /* (X) The case 1e8< abs(x)< 2**1024, 1e-7< abs(y)<= 0.0608 */
> if (ya<=gy2.d) {
> @@ -399,10 +413,10 @@ tan(double x) {
> /* First stage -cot */
> EADD(a,t2,b,db)
> DIV2(one.d,zero.d,b,db,c,dc,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c+(dc-u22.d*c))==c+(dc+u22.d*c)) return (-y); }
> + if ((y=c+(dc-u22.d*c))==c+(dc+u22.d*c)) { retval = (-y); goto ret; } }
> else {
> /* First stage tan */
> - if ((y=a+(t2-u21.d*a))==a+(t2+u21.d*a)) return y; }
> + if ((y=a+(t2-u21.d*a))==a+(t2+u21.d*a)) { retval = y; goto ret; } }
>
> /* Second stage */
> /* Reduction by algorithm iv */
> @@ -431,11 +445,12 @@ tan(double x) {
> if (n) {
> /* Second stage -cot */
> DIV2(one.d,zero.d,c1,cc1,c2,cc2,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c2+(cc2-u24.d*c2)) == c2+(cc2+u24.d*c2)) return (-y); }
> + if ((y=c2+(cc2-u24.d*c2)) == c2+(cc2+u24.d*c2)) { retval = (-y); goto ret; } }
> else {
> /* Second stage tan */
> - if ((y=c1+(cc1-u23.d*c1)) == c1+(cc1+u23.d*c1)) return y; }
> - return tanMp(x);
> + if ((y=c1+(cc1-u23.d*c1)) == c1+(cc1+u23.d*c1)) { retval = y; goto ret; } }
> + retval = tanMp(x);
> + goto ret;
> }
>
> /* (XI) The case 1e8< abs(x)< 2**1024, 0.0608< abs(y)<= 0.787 */
> @@ -448,17 +463,17 @@ tan(double x) {
> if (n) {
> /* -cot */
> t2 = pz*(fi+gi)/(fi+pz);
> - if ((y=gi-(t2-gi*u26.d))==gi-(t2+gi*u26.d)) return (-sy*y);
> + if ((y=gi-(t2-gi*u26.d))==gi-(t2+gi*u26.d)) { retval = (-sy*y); goto ret; }
> t3 = (t2<ZERO) ? -t2 : t2;
> t4 = gi*ua26.d+t3*ub26.d;
> - if ((y=gi-(t2-t4))==gi-(t2+t4)) return (-sy*y); }
> + if ((y=gi-(t2-t4))==gi-(t2+t4)) { retval = (-sy*y); goto ret; } }
> else {
> /* tan */
> t2 = pz*(gi+fi)/(gi-pz);
> - if ((y=fi+(t2-fi*u25.d))==fi+(t2+fi*u25.d)) return (sy*y);
> + if ((y=fi+(t2-fi*u25.d))==fi+(t2+fi*u25.d)) { retval = (sy*y); goto ret; }
> t3 = (t2<ZERO) ? -t2 : t2;
> t4 = fi*ua25.d+t3*ub25.d;
> - if ((y=fi+(t2-t4))==fi+(t2+t4)) return (sy*y); }
> + if ((y=fi+(t2-t4))==fi+(t2+t4)) { retval = (sy*y); goto ret; } }
>
> /* Second stage */
> ffi = xfg[i][3].d;
> @@ -479,14 +494,18 @@ tan(double x) {
> if (n) {
> /* -cot */
> DIV2(c1,cc1,c2,cc2,c3,cc3,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c3+(cc3-u28.d*c3))==c3+(cc3+u28.d*c3)) return (-sy*y); }
> + if ((y=c3+(cc3-u28.d*c3))==c3+(cc3+u28.d*c3)) { retval = (-sy*y); goto ret; } }
> else {
> /* tan */
> DIV2(c2,cc2,c1,cc1,c3,cc3,t1,t2,t3,t4,t5,t6,t7,t8,t9,t10)
> - if ((y=c3+(cc3-u27.d*c3))==c3+(cc3+u27.d*c3)) return (sy*y); }
> - return tanMp(x);
> -}
> + if ((y=c3+(cc3-u27.d*c3))==c3+(cc3+u27.d*c3)) { retval = (sy*y); goto ret; } }
> + retval = tanMp(x);
> + goto ret;
This could be if ... else without the goto ret. Or the last goto ret
could be removed (it doesn't harm but ret is the next instruction)
> + ret:
> + libc_feupdateenv (&env);
> + return retval;
> +}
Thanks for the patch, please commit after considering my suggestions,
Andreas
--
Andreas Jaeger aj@{suse.com,opensuse.org} Twitter/Identica: jaegerandi
SUSE LINUX Products GmbH, Maxfeldstr. 5, 90409 Nürnberg, Germany
GF: Jeff Hawn,Jennifer Guild,Felix Imendörffer,HRB16746 (AG Nürnberg)
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