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Code Activity

0029399: Optimize reading of floating point values from text strings

Browse Source 
Function Strtod() is reimplemented using open source (MIT-style license) code by David M. Gay instead of strtod() provided by standard run-time library. This improves its performance by 3-10 times.

Functions Atof(), Strtod(), Printf(), Sprintf(), Fprintf() are declared as extern "C" to be usable from C programs.

Strtod() is used in Interface_FileReaderData::Fastof() and in RWStl_Reader to accelerate their work.

DRAW command QATestAtof and test perf fclasses strtod are added to check correctness and performance of Strtod().
Test perf draw restore is added to monitor performance of reading BREP files.

Minor off-topic corrections:
- method Standard_GUID::Assign (const Standard_UUID&) is implemented (was empty);
- Precision.hxx is included in BRepMesh_Vertex.hxx that uses it.
This commit is contained in:
abv
2017-12-24 09:44:04 +03:00
committed by apn
parent 0edbf10564
commit 07bbde451a
16 changed files with 481 additions and 362 deletions
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207
src/Interface/Interface_FileReaderData.cxx
View File

@@ -241,210 +241,7 @@ void Interface_FileReaderData::Destroy ()
{
}
#define MAXCHIF 80
static const Standard_Real vtab[] =
{ 1., 2., 3., 4., 5., 6., 7., 8., 9.,
10., 20., 30., 40., 50., 60., 70., 80., 90.,
100., 200., 300., 400., 500., 600., 700., 800., 900.,
1000., 2000., 3000., 4000., 5000., 6000., 7000., 8000., 9000.,
10000., 20000., 30000., 40000., 50000., 60000., 70000., 80000., 90000.,
1.E+05, 2.E+05, 3.E+05, 4.E+05, 5.E+05, 6.E+05, 7.E+05, 8.E+05, 9.E+05,
1.E+06, 2.E+06, 3.E+06, 4.E+06, 5.E+06, 6.E+06, 7.E+06, 8.E+06, 9.E+06,
1.E+07, 2.E+07, 3.E+07, 4.E+07, 5.E+07, 6.E+07, 7.E+07, 8.E+07, 9.E+07,
1.E+08, 2.E+08, 3.E+08, 4.E+08, 5.E+08, 6.E+08, 7.E+08, 8.E+08, 9.E+08,
1.E+09, 2.E+09, 3.E+09, 4.E+09, 5.E+09, 6.E+09, 7.E+09, 8.E+09, 9.E+09,
1.E+10, 2.E+10, 3.E+10, 4.E+10, 5.E+10, 6.E+10, 7.E+10, 8.E+10, 9.E+10,
1.E+11, 2.E+11, 3.E+11, 4.E+11, 5.E+11, 6.E+11, 7.E+11, 8.E+11, 9.E+11,
1.E+12, 2.E+12, 3.E+12, 4.E+12, 5.E+12, 6.E+12, 7.E+12, 8.E+12, 9.E+12,
1.E+13, 2.E+13, 3.E+13, 4.E+13, 5.E+13, 6.E+13, 7.E+13, 8.E+13, 9.E+13,
1.E+14, 2.E+14, 3.E+14, 4.E+14, 5.E+14, 6.E+14, 7.E+14, 8.E+14, 9.E+14,
1.E+15, 2.E+15, 3.E+15, 4.E+15, 5.E+15, 6.E+15, 7.E+15, 8.E+15, 9.E+15,
1.E+16, 2.E+16, 3.E+16, 4.E+16, 5.E+16, 6.E+16, 7.E+16, 8.E+16, 9.E+16,
1.E+17, 2.E+17, 3.E+17, 4.E+17, 5.E+17, 6.E+17, 7.E+17, 8.E+17, 9.E+17,
1.E+18, 2.E+18, 3.E+18, 4.E+18, 5.E+18, 6.E+18, 7.E+18, 8.E+18, 9.E+18,
1.E+19, 2.E+19, 3.E+19, 4.E+19, 5.E+19, 6.E+19, 7.E+19, 8.E+19, 9.E+19,
1.E+20, 2.E+20, 3.E+20, 4.E+20, 5.E+20, 6.E+20, 7.E+20, 8.E+20, 9.E+20,
1.E+21, 2.E+21, 3.E+21, 4.E+21, 5.E+21, 6.E+21, 7.E+21, 8.E+21, 9.E+21,
1.E+22, 2.E+22, 3.E+22, 4.E+22, 5.E+22, 6.E+22, 7.E+22, 8.E+22, 9.E+22,
1.E+23, 2.E+23, 3.E+23, 4.E+23, 5.E+23, 6.E+23, 7.E+23, 8.E+23, 9.E+23,
1.E+24, 2.E+24, 3.E+24, 4.E+24, 5.E+24, 6.E+24, 7.E+24, 8.E+24, 9.E+24,
1.E+25, 2.E+25, 3.E+25, 4.E+25, 5.E+25, 6.E+25, 7.E+25, 8.E+25, 9.E+25,
1.E+26, 2.E+26, 3.E+26, 4.E+26, 5.E+26, 6.E+26, 7.E+26, 8.E+26, 9.E+26,
1.E+27, 2.E+27, 3.E+27, 4.E+27, 5.E+27, 6.E+27, 7.E+27, 8.E+27, 9.E+27,
1.E+28, 2.E+28, 3.E+28, 4.E+28, 5.E+28, 6.E+28, 7.E+28, 8.E+28, 9.E+28,
1.E+29, 2.E+29, 3.E+29, 4.E+29, 5.E+29, 6.E+29, 7.E+29, 8.E+29, 9.E+29,
1.E+30, 2.E+30, 3.E+30, 4.E+30, 5.E+30, 6.E+30, 7.E+30, 8.E+30, 9.E+30,
1.E+31, 2.E+31, 3.E+31, 4.E+31, 5.E+31, 6.E+31, 7.E+31, 8.E+31, 9.E+31,
1.E+32, 2.E+32, 3.E+32, 4.E+32, 5.E+32, 6.E+32, 7.E+32, 8.E+32, 9.E+32,
1.E+33, 2.E+33, 3.E+33, 4.E+33, 5.E+33, 6.E+33, 7.E+33, 8.E+33, 9.E+33,
1.E+34, 2.E+34, 3.E+34, 4.E+34, 5.E+34, 6.E+34, 7.E+34, 8.E+34, 9.E+34,
1.E+35, 2.E+35, 3.E+35, 4.E+35, 5.E+35, 6.E+35, 7.E+35, 8.E+35, 9.E+35,
1.E+36, 2.E+36, 3.E+36, 4.E+36, 5.E+36, 6.E+36, 7.E+36, 8.E+36, 9.E+36,
1.E+37, 2.E+37, 3.E+37, 4.E+37, 5.E+37, 6.E+37, 7.E+37, 8.E+37, 9.E+37,
1.E+38, 2.E+38, 3.E+38, 4.E+38, 5.E+38, 6.E+38, 7.E+38, 8.E+38, 9.E+38,
1.E+39, 2.E+39, 3.E+39, 4.E+39, 5.E+39, 6.E+39, 7.E+39, 8.E+39, 9.E+39,
1.E+40, 2.E+40, 3.E+40, 4.E+40, 5.E+40, 6.E+40, 7.E+40, 8.E+40, 9.E+40,
1.E+41, 2.E+41, 3.E+41, 4.E+41, 5.E+41, 6.E+41, 7.E+41, 8.E+41, 9.E+41,
1.E+42, 2.E+42, 3.E+42, 4.E+42, 5.E+42, 6.E+42, 7.E+42, 8.E+42, 9.E+42,
1.E+43, 2.E+43, 3.E+43, 4.E+43, 5.E+43, 6.E+43, 7.E+43, 8.E+43, 9.E+43,
1.E+44, 2.E+44, 3.E+44, 4.E+44, 5.E+44, 6.E+44, 7.E+44, 8.E+44, 9.E+44,
1.E+45, 2.E+45, 3.E+45, 4.E+45, 5.E+45, 6.E+45, 7.E+45, 8.E+45, 9.E+45,
1.E+46, 2.E+46, 3.E+46, 4.E+46, 5.E+46, 6.E+46, 7.E+46, 8.E+46, 9.E+46,
1.E+47, 2.E+47, 3.E+47, 4.E+47, 5.E+47, 6.E+47, 7.E+47, 8.E+47, 9.E+47,
1.E+48, 2.E+48, 3.E+48, 4.E+48, 5.E+48, 6.E+48, 7.E+48, 8.E+48, 9.E+48,
1.E+49, 2.E+49, 3.E+49, 4.E+49, 5.E+49, 6.E+49, 7.E+49, 8.E+49, 9.E+49,
1.E+50, 2.E+50, 3.E+50, 4.E+50, 5.E+50, 6.E+50, 7.E+50, 8.E+50, 9.E+50,
1.E+51, 2.E+51, 3.E+51, 4.E+51, 5.E+51, 6.E+51, 7.E+51, 8.E+51, 9.E+51,
1.E+52, 2.E+52, 3.E+52, 4.E+52, 5.E+52, 6.E+52, 7.E+52, 8.E+52, 9.E+52,
1.E+53, 2.E+53, 3.E+53, 4.E+53, 5.E+53, 6.E+53, 7.E+53, 8.E+53, 9.E+53,
1.E+54, 2.E+54, 3.E+54, 4.E+54, 5.E+54, 6.E+54, 7.E+54, 8.E+54, 9.E+54,
1.E+55, 2.E+55, 3.E+55, 4.E+55, 5.E+55, 6.E+55, 7.E+55, 8.E+55, 9.E+55,
1.E+56, 2.E+56, 3.E+56, 4.E+56, 5.E+56, 6.E+56, 7.E+56, 8.E+56, 9.E+56,
1.E+57, 2.E+57, 3.E+57, 4.E+57, 5.E+57, 6.E+57, 7.E+57, 8.E+57, 9.E+57,
1.E+58, 2.E+58, 3.E+58, 4.E+58, 5.E+58, 6.E+58, 7.E+58, 8.E+58, 9.E+58,
1.E+59, 2.E+59, 3.E+59, 4.E+59, 5.E+59, 6.E+59, 7.E+59, 8.E+59, 9.E+59,
1.E+60, 2.E+60, 3.E+60, 4.E+60, 5.E+60, 6.E+60, 7.E+60, 8.E+60, 9.E+60,
1.E+61, 2.E+61, 3.E+61, 4.E+61, 5.E+61, 6.E+61, 7.E+61, 8.E+61, 9.E+61,
1.E+62, 2.E+62, 3.E+62, 4.E+62, 5.E+62, 6.E+62, 7.E+62, 8.E+62, 9.E+62,
1.E+63, 2.E+63, 3.E+63, 4.E+63, 5.E+63, 6.E+63, 7.E+63, 8.E+63, 9.E+63,
1.E+64, 2.E+64, 3.E+64, 4.E+64, 5.E+64, 6.E+64, 7.E+64, 8.E+64, 9.E+64,
1.E+65, 2.E+65, 3.E+65, 4.E+65, 5.E+65, 6.E+65, 7.E+65, 8.E+65, 9.E+65,
1.E+66, 2.E+66, 3.E+66, 4.E+66, 5.E+66, 6.E+66, 7.E+66, 8.E+66, 9.E+66,
1.E+67, 2.E+67, 3.E+67, 4.E+67, 5.E+67, 6.E+67, 7.E+67, 8.E+67, 9.E+67,
1.E+68, 2.E+68, 3.E+68, 4.E+68, 5.E+68, 6.E+68, 7.E+68, 8.E+68, 9.E+68,
1.E+69, 2.E+69, 3.E+69, 4.E+69, 5.E+69, 6.E+69, 7.E+69, 8.E+69, 9.E+69,
1.E+70, 2.E+70, 3.E+70, 4.E+70, 5.E+70, 6.E+70, 7.E+70, 8.E+70, 9.E+70,
1.E+71, 2.E+71, 3.E+71, 4.E+71, 5.E+71, 6.E+71, 7.E+71, 8.E+71, 9.E+71,
1.E+72, 2.E+72, 3.E+72, 4.E+72, 5.E+72, 6.E+72, 7.E+72, 8.E+72, 9.E+72,
1.E+73, 2.E+73, 3.E+73, 4.E+73, 5.E+73, 6.E+73, 7.E+73, 8.E+73, 9.E+73,
1.E+74, 2.E+74, 3.E+74, 4.E+74, 5.E+74, 6.E+74, 7.E+74, 8.E+74, 9.E+74,
1.E+75, 2.E+75, 3.E+75, 4.E+75, 5.E+75, 6.E+75, 7.E+75, 8.E+75, 9.E+75,
1.E+76, 2.E+76, 3.E+76, 4.E+76, 5.E+76, 6.E+76, 7.E+76, 8.E+76, 9.E+76,
1.E+77, 2.E+77, 3.E+77, 4.E+77, 5.E+77, 6.E+77, 7.E+77, 8.E+77, 9.E+77,
1.E+78, 2.E+78, 3.E+78, 4.E+78, 5.E+78, 6.E+78, 7.E+78, 8.E+78, 9.E+78,
1.E+79, 2.E+79, 3.E+79, 4.E+79, 5.E+79, 6.E+79, 7.E+79, 8.E+79, 9.E+79,
1.E+80, 2.E+80, 3.E+80, 4.E+80, 5.E+80, 6.E+80, 7.E+80, 8.E+80, 9.E+80,
1.E+81, 2.E+81, 3.E+81, 4.E+81, 5.E+81, 6.E+81, 7.E+81, 8.E+81, 9.E+81,
1.E+82, 2.E+82, 3.E+82, 4.E+82, 5.E+82, 6.E+82, 7.E+82, 8.E+82, 9.E+82,
1.E+83, 2.E+83, 3.E+83, 4.E+83, 5.E+83, 6.E+83, 7.E+83, 8.E+83, 9.E+83,
1.E+84, 2.E+84, 3.E+84, 4.E+84, 5.E+84, 6.E+84, 7.E+84, 8.E+84, 9.E+84,
1.E+85, 2.E+85, 3.E+85, 4.E+85, 5.E+85, 6.E+85, 7.E+85, 8.E+85, 9.E+85,
1.E+86, 2.E+86, 3.E+86, 4.E+86, 5.E+86, 6.E+86, 7.E+86, 8.E+86, 9.E+86,
1.E+87, 2.E+87, 3.E+87, 4.E+87, 5.E+87, 6.E+87, 7.E+87, 8.E+87, 9.E+87,
1.E+88, 2.E+88, 3.E+88, 4.E+88, 5.E+88, 6.E+88, 7.E+88, 8.E+88, 9.E+88,
1.E+89, 2.E+89, 3.E+89, 4.E+89, 5.E+89, 6.E+89, 7.E+89, 8.E+89, 9.E+89,
1.E+90, 2.E+90, 3.E+90, 4.E+90, 5.E+90, 6.E+90, 7.E+90, 8.E+90, 9.E+90,
1.E+91, 2.E+91, 3.E+91, 4.E+91, 5.E+91, 6.E+91, 7.E+91, 8.E+91, 9.E+91,
1.E+92, 2.E+92, 3.E+92, 4.E+92, 5.E+92, 6.E+92, 7.E+92, 8.E+92, 9.E+92,
1.E+93, 2.E+93, 3.E+93, 4.E+93, 5.E+93, 6.E+93, 7.E+93, 8.E+93, 9.E+93,
1.E+94, 2.E+94, 3.E+94, 4.E+94, 5.E+94, 6.E+94, 7.E+94, 8.E+94, 9.E+94,
1.E+95, 2.E+95, 3.E+95, 4.E+95, 5.E+95, 6.E+95, 7.E+95, 8.E+95, 9.E+95,
1.E+96, 2.E+96, 3.E+96, 4.E+96, 5.E+96, 6.E+96, 7.E+96, 8.E+96, 9.E+96,
1.E+97, 2.E+97, 3.E+97, 4.E+97, 5.E+97, 6.E+97, 7.E+97, 8.E+97, 9.E+97,
1.E+98, 2.E+98, 3.E+98, 4.E+98, 5.E+98, 6.E+98, 7.E+98, 8.E+98, 9.E+98,
1.E+99, 2.E+99, 3.E+99, 4.E+99, 5.E+99, 6.E+99, 7.E+99, 8.E+99, 9.E+99 };
Standard_Real Interface_FileReaderData::Fastof (const Standard_CString ligne)
Standard_Real Interface_FileReaderData::Fastof (const Standard_CString ligne)
{
Standard_Real val = 0., valdiv;
int i, jj, j, k, je, jx;
int chiffre[MAXCHIF]; int point, prem, moins, exp, grexp;
j = jj = je = jx = 0;
moins = exp = grexp = 0;
prem = MAXCHIF + 1; point = -1; // ligne[MAXCHIF+1] = '\0'; fin forcee
/* Analyse de la ligne (reputee representer un Flottant) */
for (i = 0; ; i ++) // critere d arret : cf '\0'
{
const char& car = ligne[i];
/* critere d arret : ne pas l oublier, mais eviter de freiner le traitement
DONC, une fois en fin, plus une fois pour 1er passage
if (car == '\0')
{ if (point < 0) { point = i; jx = point - prem; }; break; } */
if (prem > MAXCHIF)
{
if (car == '0') continue;
if (car == '.') { point = i; continue; }
if (car == '+') continue;
if (car == '-') { moins = 1; continue; }
if (car == '\0')
{
if (point < 0)
{
point = i;
jx = point - prem;
}
break;
}
if (car < 33)
{
continue;
}
prem = i;
if (point >= 0)
{
jx = point - prem + 1;
}
}
if (car > 48 && car <= 57)
{
chiffre[j] = car - 48;
jj = ++j; // j++ puis jj = j
continue;
}
if (car == '0') { chiffre[j] = 0; j ++; continue; }
if (car == '.') { point = i; jx = point - prem; continue; }
if ((car & 94) == 68) { // prend : e E d D
je = i; exp = atoi(&ligne[i+1]); jx += exp;
if (exp < -100 || exp > 100)
{
grexp = 1;
}
break;
}
if (car == '\0')
{
if (point < 0)
{
point = i;
jx = point - prem;
}
break;
}
}
/* Interpretation : on decale le Point Decimal selon l Exposant
Puis on considere par rapport a <jj>, <prem> :
chiffre[i, pour i < point - prem] : partie entiere
chiffre[i, pour i >= point - prem] : partie decimale
*/
// jx = (point < prem ? point - prem + 1 : point - prem) + exp; deja calcule
// Puissance de 10 premiere decimale <0>
// limite : le PLUS PETIT SIGNIFIANT doit etre >= 1e-99
je = jx*9;
if (jx > jj) {
valdiv = 1.;
if (jx >= 100 || grexp) return Atof(ligne); // issue de secours
} else {
k = jj*9;
if (jj >= 100 || grexp || (k-je >= 900)) return Atof(ligne); // issue de secours
valdiv = vtab[k-je];
je = k;
}
je --;
// val = 0.; mis a la creation
for (i = 0; i < jj; i ++) {
je -= 9;
const int& chif = chiffre[i];
if (chif != 0) val += vtab[chif+je];
}
if (valdiv != 1.) val = val/valdiv;
if (moins) val = -val;
return val;
return Strtod (ligne, 0);
}