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[RFC] DO_NOT_USE_THIS - do not use this.
- From: OndÅej BÃlka <neleai at seznam dot cz>
- To: libc-alpha at sourceware dot org
- Date: Tue, 3 Sep 2013 16:44:42 +0200
- Subject: [RFC] DO_NOT_USE_THIS - do not use this.
- Authentication-results: sourceware.org; auth=none
Hi, when looking a cppcheck code we found blocks surrounded by
ifdef DO_NOT_USE_THIS.
They are now out of sync with code they are supposed to explain.
Should we remove them or change them to comment?
If we decide for removal then following patch is applicable.
---
sysdeps/ieee754/dbl-64/e_j0.c | 20 -----------------
sysdeps/ieee754/dbl-64/e_j1.c | 21 ------------------
sysdeps/ieee754/dbl-64/s_erf.c | 48 ----------------------------------------
sysdeps/ieee754/dbl-64/s_expm1.c | 4 ----
sysdeps/ieee754/dbl-64/s_log1p.c | 4 ----
5 files changed, 97 deletions(-)
diff --git a/sysdeps/ieee754/dbl-64/e_j0.c b/sysdeps/ieee754/dbl-64/e_j0.c
index d641a09..ca54275 100644
--- a/sysdeps/ieee754/dbl-64/e_j0.c
+++ b/sysdeps/ieee754/dbl-64/e_j0.c
@@ -116,17 +116,12 @@ __ieee754_j0(double x)
else return one - 0.25*x*x;
}
z = x*x;
-#ifdef DO_NOT_USE_THIS
- r = z*(R02+z*(R03+z*(R04+z*R05)));
- s = one+z*(S01+z*(S02+z*(S03+z*S04)));
-#else
r1 = z*R[2]; z2=z*z;
r2 = R[3]+z*R[4]; z4=z2*z2;
r = r1 + z2*r2 + z4*R[5];
s1 = one+z*S[1];
s2 = S[2]+z*S[3];
s = s1 + z2*s2 + z4*S[4];
-#endif
if(ix < 0x3FF00000) { /* |x| < 1.00 */
return one + z*(-0.25+(r/s));
} else {
@@ -196,10 +191,6 @@ __ieee754_y0(double x)
return(U[0] + tpi*__ieee754_log(x));
}
z = x*x;
-#ifdef DO_NOT_USE_THIS
- u = u00+z*(u01+z*(u02+z*(u03+z*(u04+z*(u05+z*u06)))));
- v = one+z*(v01+z*(v02+z*(v03+z*v04)));
-#else
u1 = U[0]+z*U[1]; z2=z*z;
u2 = U[2]+z*U[3]; z4=z2*z2;
u3 = U[4]+z*U[5]; z6=z4*z2;
@@ -207,7 +198,6 @@ __ieee754_y0(double x)
v1 = one+z*V[0];
v2 = V[1]+z*V[2];
v = v1 + z2*v2 + z4*V[3];
-#endif
return(u/v + tpi*(__ieee754_j0(x)*__ieee754_log(x)));
}
strong_alias (__ieee754_y0, __y0_finite)
@@ -299,10 +289,6 @@ pzero(double x)
else if(ix>=0x4006DB6D){p = pR3; q= pS3;}
else if(ix>=0x40000000){p = pR2; q= pS2;}
z = one/(x*x);
-#ifdef DO_NOT_USE_THIS
- r = p[0]+z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))));
- s = one+z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))));
-#else
r1 = p[0]+z*p[1]; z2=z*z;
r2 = p[2]+z*p[3]; z4=z2*z2;
r3 = p[4]+z*p[5];
@@ -311,7 +297,6 @@ pzero(double x)
s2 = q[1]+z*q[2];
s3 = q[3]+z*q[4];
s = s1 + z2*s2 + z4*s3;
-#endif
return one+ r/s;
}
@@ -407,10 +392,6 @@ qzero(double x)
else if(ix>=0x4006DB6D){p = qR3; q= qS3;}
else if(ix>=0x40000000){p = qR2; q= qS2;}
z = one/(x*x);
-#ifdef DO_NOT_USE_THIS
- r = p[0]+z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))));
- s = one+z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))));
-#else
r1 = p[0]+z*p[1]; z2=z*z;
r2 = p[2]+z*p[3]; z4=z2*z2;
r3 = p[4]+z*p[5]; z6=z4*z2;
@@ -419,6 +400,5 @@ qzero(double x)
s2 = q[1]+z*q[2];
s3 = q[3]+z*q[4];
s = s1 + z2*s2 + z4*s3 +z6*q[5];
-#endif
return (-.125 + r/s)/x;
}
diff --git a/sysdeps/ieee754/dbl-64/e_j1.c b/sysdeps/ieee754/dbl-64/e_j1.c
index cca5f20..12d5c40 100644
--- a/sysdeps/ieee754/dbl-64/e_j1.c
+++ b/sysdeps/ieee754/dbl-64/e_j1.c
@@ -116,11 +116,6 @@ __ieee754_j1(double x)
if(huge+x>one) return 0.5*x;/* inexact if x!=0 necessary */
}
z = x*x;
-#ifdef DO_NOT_USE_THIS
- r = z*(r00+z*(r01+z*(r02+z*r03)));
- s = one+z*(s01+z*(s02+z*(s03+z*(s04+z*s05))));
- r *= x;
-#else
r1 = z*R[0]; z2=z*z;
r2 = R[1]+z*R[2]; z4=z2*z2;
r = r1 + z2*r2 + z4*R[3];
@@ -129,7 +124,6 @@ __ieee754_j1(double x)
s2 = S[2]+z*S[3];
s3 = S[4]+z*S[5];
s = s1 + z2*s2 + z4*s3;
-#endif
return(x*0.5+r/s);
}
strong_alias (__ieee754_j1, __j1_finite)
@@ -193,10 +187,6 @@ __ieee754_y1(double x)
return(-tpi/x);
}
z = x*x;
-#ifdef DO_NOT_USE_THIS
- u = U0[0]+z*(U0[1]+z*(U0[2]+z*(U0[3]+z*U0[4])));
- v = one+z*(V0[0]+z*(V0[1]+z*(V0[2]+z*(V0[3]+z*V0[4]))));
-#else
u1 = U0[0]+z*U0[1];z2=z*z;
u2 = U0[2]+z*U0[3];z4=z2*z2;
u = u1 + z2*u2 + z4*U0[4];
@@ -204,7 +194,6 @@ __ieee754_y1(double x)
v2 = V0[1]+z*V0[2];
v3 = V0[3]+z*V0[4];
v = v1 + z2*v2 + z4*v3;
-#endif
return(x*(u/v) + tpi*(__ieee754_j1(x)*__ieee754_log(x)-one/x));
}
strong_alias (__ieee754_y1, __y1_finite)
@@ -297,10 +286,6 @@ pone(double x)
else if(ix>=0x4006DB6D){p = pr3; q= ps3;}
else if(ix>=0x40000000){p = pr2; q= ps2;}
z = one/(x*x);
-#ifdef DO_NOT_USE_THIS
- r = p[0]+z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))));
- s = one+z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*q[4]))));
-#else
r1 = p[0]+z*p[1]; z2=z*z;
r2 = p[2]+z*p[3]; z4=z2*z2;
r3 = p[4]+z*p[5];
@@ -309,7 +294,6 @@ pone(double x)
s2 = q[1]+z*q[2];
s3 = q[3]+z*q[4];
s = s1 + z2*s2 + z4*s3;
-#endif
return one+ r/s;
}
@@ -406,10 +390,6 @@ qone(double x)
else if(ix>=0x4006DB6D){p = qr3; q= qs3;}
else if(ix>=0x40000000){p = qr2; q= qs2;}
z = one/(x*x);
-#ifdef DO_NOT_USE_THIS
- r = p[0]+z*(p[1]+z*(p[2]+z*(p[3]+z*(p[4]+z*p[5]))));
- s = one+z*(q[0]+z*(q[1]+z*(q[2]+z*(q[3]+z*(q[4]+z*q[5])))));
-#else
r1 = p[0]+z*p[1]; z2=z*z;
r2 = p[2]+z*p[3]; z4=z2*z2;
r3 = p[4]+z*p[5]; z6=z4*z2;
@@ -418,6 +398,5 @@ qone(double x)
s2 = q[1]+z*q[2];
s3 = q[3]+z*q[4];
s = s1 + z2*s2 + z4*s3 + z6*q[5];
-#endif
return (.375 + r/s)/x;
}
diff --git a/sysdeps/ieee754/dbl-64/s_erf.c b/sysdeps/ieee754/dbl-64/s_erf.c
index e25e28d..0cf408c 100644
--- a/sysdeps/ieee754/dbl-64/s_erf.c
+++ b/sysdeps/ieee754/dbl-64/s_erf.c
@@ -209,10 +209,6 @@ double __erf(double x)
return x + efx*x;
}
z = x*x;
-#ifdef DO_NOT_USE_THIS
- r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)));
- s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
-#else
r1 = pp[0]+z*pp[1]; z2=z*z;
r2 = pp[2]+z*pp[3]; z4=z2*z2;
s1 = one+z*qq[1];
@@ -220,17 +216,12 @@ double __erf(double x)
s3 = qq[4]+z*qq[5];
r = r1 + z2*r2 + z4*pp[4];
s = s1 + z2*s2 + z4*s3;
-#endif
y = r/s;
return x + x*y;
}
if(ix < 0x3ff40000) { /* 0.84375 <= |x| < 1.25 */
double s2,s4,s6,P1,P2,P3,P4,Q1,Q2,Q3,Q4;
s = fabs(x)-one;
-#ifdef DO_NOT_USE_THIS
- P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))));
- Q = one+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
-#else
P1 = pa[0]+s*pa[1]; s2=s*s;
Q1 = one+s*qa[1]; s4=s2*s2;
P2 = pa[2]+s*pa[3]; s6=s4*s2;
@@ -241,7 +232,6 @@ double __erf(double x)
Q4 = qa[6];
P = P1 + s2*P2 + s4*P3 + s6*P4;
Q = Q1 + s2*Q2 + s4*Q3 + s6*Q4;
-#endif
if(hx>=0) return erx + P/Q; else return -erx - P/Q;
}
if (ix >= 0x40180000) { /* inf>|x|>=6 */
@@ -250,12 +240,6 @@ double __erf(double x)
x = fabs(x);
s = one/(x*x);
if(ix< 0x4006DB6E) { /* |x| < 1/0.35 */
-#ifdef DO_NOT_USE_THIS
- R=ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(
- ra5+s*(ra6+s*ra7))))));
- S=one+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(
- sa5+s*(sa6+s*(sa7+s*sa8)))))));
-#else
double R1,R2,R3,R4,S1,S2,S3,S4,s2,s4,s6,s8;
R1 = ra[0]+s*ra[1];s2 = s*s;
S1 = one+s*sa[1]; s4 = s2*s2;
@@ -267,14 +251,7 @@ double __erf(double x)
S4 = sa[6]+s*sa[7];
R = R1 + s2*R2 + s4*R3 + s6*R4;
S = S1 + s2*S2 + s4*S3 + s6*S4 + s8*sa[8];
-#endif
} else { /* |x| >= 1/0.35 */
-#ifdef DO_NOT_USE_THIS
- R=rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(
- rb5+s*rb6)))));
- S=one+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(
- sb5+s*(sb6+s*sb7))))));
-#else
double R1,R2,R3,S1,S2,S3,S4,s2,s4,s6;
R1 = rb[0]+s*rb[1];s2 = s*s;
S1 = one+s*sb[1]; s4 = s2*s2;
@@ -285,7 +262,6 @@ double __erf(double x)
S4 = sb[6]+s*sb[7];
R = R1 + s2*R2 + s4*R3 + s6*rb[6];
S = S1 + s2*S2 + s4*S3 + s6*S4;
-#endif
}
z = x;
SET_LOW_WORD(z,0);
@@ -314,10 +290,6 @@ double __erfc(double x)
if(ix < 0x3c700000) /* |x|<2**-56 */
return one-x;
z = x*x;
-#ifdef DO_NOT_USE_THIS
- r = pp0+z*(pp1+z*(pp2+z*(pp3+z*pp4)));
- s = one+z*(qq1+z*(qq2+z*(qq3+z*(qq4+z*qq5))));
-#else
r1 = pp[0]+z*pp[1]; z2=z*z;
r2 = pp[2]+z*pp[3]; z4=z2*z2;
s1 = one+z*qq[1];
@@ -325,7 +297,6 @@ double __erfc(double x)
s3 = qq[4]+z*qq[5];
r = r1 + z2*r2 + z4*pp[4];
s = s1 + z2*s2 + z4*s3;
-#endif
y = r/s;
if(hx < 0x3fd00000) { /* x<1/4 */
return one-(x+x*y);
@@ -338,10 +309,6 @@ double __erfc(double x)
if(ix < 0x3ff40000) { /* 0.84375 <= |x| < 1.25 */
double s2,s4,s6,P1,P2,P3,P4,Q1,Q2,Q3,Q4;
s = fabs(x)-one;
-#ifdef DO_NOT_USE_THIS
- P = pa0+s*(pa1+s*(pa2+s*(pa3+s*(pa4+s*(pa5+s*pa6)))));
- Q = one+s*(qa1+s*(qa2+s*(qa3+s*(qa4+s*(qa5+s*qa6)))));
-#else
P1 = pa[0]+s*pa[1]; s2=s*s;
Q1 = one+s*qa[1]; s4=s2*s2;
P2 = pa[2]+s*pa[3]; s6=s4*s2;
@@ -352,7 +319,6 @@ double __erfc(double x)
Q4 = qa[6];
P = P1 + s2*P2 + s4*P3 + s6*P4;
Q = Q1 + s2*Q2 + s4*Q3 + s6*Q4;
-#endif
if(hx>=0) {
z = one-erx; return z - P/Q;
} else {
@@ -363,12 +329,6 @@ double __erfc(double x)
x = fabs(x);
s = one/(x*x);
if(ix< 0x4006DB6D) { /* |x| < 1/.35 ~ 2.857143*/
-#ifdef DO_NOT_USE_THIS
- R=ra0+s*(ra1+s*(ra2+s*(ra3+s*(ra4+s*(
- ra5+s*(ra6+s*ra7))))));
- S=one+s*(sa1+s*(sa2+s*(sa3+s*(sa4+s*(
- sa5+s*(sa6+s*(sa7+s*sa8)))))));
-#else
double R1,R2,R3,R4,S1,S2,S3,S4,s2,s4,s6,s8;
R1 = ra[0]+s*ra[1];s2 = s*s;
S1 = one+s*sa[1]; s4 = s2*s2;
@@ -380,16 +340,9 @@ double __erfc(double x)
S4 = sa[6]+s*sa[7];
R = R1 + s2*R2 + s4*R3 + s6*R4;
S = S1 + s2*S2 + s4*S3 + s6*S4 + s8*sa[8];
-#endif
} else { /* |x| >= 1/.35 ~ 2.857143 */
double R1,R2,R3,S1,S2,S3,S4,s2,s4,s6;
if(hx<0&&ix>=0x40180000) return two-tiny;/* x < -6 */
-#ifdef DO_NOT_USE_THIS
- R=rb0+s*(rb1+s*(rb2+s*(rb3+s*(rb4+s*(
- rb5+s*rb6)))));
- S=one+s*(sb1+s*(sb2+s*(sb3+s*(sb4+s*(
- sb5+s*(sb6+s*sb7))))));
-#else
R1 = rb[0]+s*rb[1];s2 = s*s;
S1 = one+s*sb[1]; s4 = s2*s2;
R2 = rb[2]+s*rb[3];s6 = s4*s2;
@@ -399,7 +352,6 @@ double __erfc(double x)
S4 = sb[6]+s*sb[7];
R = R1 + s2*R2 + s4*R3 + s6*rb[6];
S = S1 + s2*S2 + s4*S3 + s6*S4;
-#endif
}
z = x;
SET_LOW_WORD(z,0);
diff --git a/sysdeps/ieee754/dbl-64/s_expm1.c b/sysdeps/ieee754/dbl-64/s_expm1.c
index 1a4bcd9..87da7eb 100644
--- a/sysdeps/ieee754/dbl-64/s_expm1.c
+++ b/sysdeps/ieee754/dbl-64/s_expm1.c
@@ -184,14 +184,10 @@ __expm1(double x)
/* x is now in primary range */
hfx = 0.5*x;
hxs = x*hfx;
-#ifdef DO_NOT_USE_THIS
- r1 = one+hxs*(Q1+hxs*(Q2+hxs*(Q3+hxs*(Q4+hxs*Q5))));
-#else
R1 = one+hxs*Q[1]; h2 = hxs*hxs;
R2 = Q[2]+hxs*Q[3]; h4 = h2*h2;
R3 = Q[4]+hxs*Q[5];
r1 = R1 + h2*R2 + h4*R3;
-#endif
t = 3.0-r1*hfx;
e = hxs*((r1-t)/(6.0 - x*t));
if(k==0) return x - (x*e-hxs); /* c is 0 */
diff --git a/sysdeps/ieee754/dbl-64/s_log1p.c b/sysdeps/ieee754/dbl-64/s_log1p.c
index e3e6860..0c6f763 100644
--- a/sysdeps/ieee754/dbl-64/s_log1p.c
+++ b/sysdeps/ieee754/dbl-64/s_log1p.c
@@ -156,15 +156,11 @@ __log1p(double x)
}
s = f/(2.0+f);
z = s*s;
-#ifdef DO_NOT_USE_THIS
- R = z*(Lp1+z*(Lp2+z*(Lp3+z*(Lp4+z*(Lp5+z*(Lp6+z*Lp7))))));
-#else
R1 = z*Lp[1]; z2=z*z;
R2 = Lp[2]+z*Lp[3]; z4=z2*z2;
R3 = Lp[4]+z*Lp[5]; z6=z4*z2;
R4 = Lp[6]+z*Lp[7];
R = R1 + z2*R2 + z4*R3 + z6*R4;
-#endif
if(k==0) return f-(hfsq-s*(hfsq+R)); else
return k*ln2_hi-((hfsq-(s*(hfsq+R)+(k*ln2_lo+c)))-f);
}
--
1.8.3.2