From 85b4eb08ccf03edb01b2b9cee11c27717be140b8 Mon Sep 17 00:00:00 2001 From: Oded Shimon Date: Fri, 27 Oct 2006 16:42:16 +0000 Subject: [PATCH] new optimized eval method, by seperating parsing and runtime Originally committed as revision 6803 to svn://svn.ffmpeg.org/ffmpeg/trunk --- libavcodec/eval.c | 258 ++++++++++++++++++++++++++++++++++------------ libavcodec/eval.h | 8 ++ 2 files changed, 202 insertions(+), 64 deletions(-) diff --git a/libavcodec/eval.c b/libavcodec/eval.c index a676b95ca7..4957f52712 100644 --- a/libavcodec/eval.c +++ b/libavcodec/eval.c @@ -30,6 +30,7 @@ #include "avcodec.h" #include "mpegvideo.h" +#include "eval.h" #include #include @@ -57,8 +58,6 @@ typedef struct Parser{ char **error; } Parser; -static double evalExpression(Parser *p); - static int8_t si_prefixes['z' - 'E' + 1]={ ['y'-'E']= -24, ['z'-'E']= -21, @@ -126,23 +125,82 @@ static int strmatch(const char *s, const char *prefix){ return 1; } -static double evalPrimary(Parser *p){ - double d, d2=NAN; +struct ff_expr_s { + enum { + e_value, e_const, e_func0, e_func1, e_func2, + e_squish, e_gauss, + e_mod, e_max, e_min, e_eq, e_gt, e_gte, + e_pow, e_mul, e_div, e_add, + } type; + double value; // is sign in other types + union { + int const_index; + double (*func0)(double); + double (*func1)(void *, double); + double (*func2)(void *, double, double); + } a; + AVEvalExpr * param[2]; +}; + +static double eval_expr(Parser * p, AVEvalExpr * e) { + switch (e->type) { + case e_value: return e->value; + case e_const: return e->value * p->const_value[e->a.const_index]; + case e_func0: return e->value * e->a.func0(eval_expr(p, e->param[0])); + case e_func1: return e->value * e->a.func1(p->opaque, eval_expr(p, e->param[0])); + case e_func2: return e->value * e->a.func2(p->opaque, eval_expr(p, e->param[0]), eval_expr(p, e->param[1])); + case e_squish: return 1/(1+exp(4*eval_expr(p, e->param[0]))); + case e_gauss: { double d = eval_expr(p, e->param[0]); return exp(-d*d/2)/sqrt(2*M_PI); } + default: { + double d = eval_expr(p, e->param[0]); + double d2 = eval_expr(p, e->param[1]); + switch (e->type) { + case e_mod: return e->value * (d - floor(d/d2)*d2); + case e_max: return e->value * (d > d2 ? d : d2); + case e_min: return e->value * (d < d2 ? d : d2); + case e_eq: return e->value * (d == d2 ? 1.0 : 0.0); + case e_gt: return e->value * (d > d2 ? 1.0 : 0.0); + case e_gte: return e->value * (d >= d2 ? 1.0 : 0.0); + case e_pow: return e->value * pow(d, d2); + case e_mul: return e->value * (d * d2); + case e_div: return e->value * (d / d2); + case e_add: return e->value * (d + d2); + } + } + } + return NAN; +} + +static AVEvalExpr * parse_expr(Parser *p); + +void ff_eval_free(AVEvalExpr * e) { + if (!e) return; + ff_eval_free(e->param[0]); + ff_eval_free(e->param[1]); + av_freep(&e); +} + +static AVEvalExpr * parse_primary(Parser *p) { + AVEvalExpr * d = av_mallocz(sizeof(AVEvalExpr)); char *next= p->s; int i; /* number */ - d= av_strtod(p->s, &next); + d->value = av_strtod(p->s, &next); if(next != p->s){ + d->type = e_value; p->s= next; return d; } + d->value = 1; /* named constants */ for(i=0; p->const_name && p->const_name[i]; i++){ if(strmatch(p->s, p->const_name[i])){ p->s+= strlen(p->const_name[i]); - return p->const_value[i]; + d->type = e_const; + d->a.const_index = i; + return d; } } @@ -150,126 +208,198 @@ static double evalPrimary(Parser *p){ if(p->s==NULL){ *p->error = "missing ("; p->s= next; - return NAN; + ff_eval_free(d); + return NULL; } p->s++; // "(" - d= evalExpression(p); + if (*next == '(') { // special case do-nothing + av_freep(&d); + d = parse_expr(p); + if(p->s[0] != ')'){ + *p->error = "missing )"; + ff_eval_free(d); + return NULL; + } + p->s++; // ")" + return d; + } + d->param[0] = parse_expr(p); if(p->s[0]== ','){ p->s++; // "," - d2= evalExpression(p); + d->param[1] = parse_expr(p); } if(p->s[0] != ')'){ *p->error = "missing )"; - return NAN; + ff_eval_free(d); + return NULL; } p->s++; // ")" - if( strmatch(next, "sinh" ) ) d= sinh(d); - else if( strmatch(next, "cosh" ) ) d= cosh(d); - else if( strmatch(next, "tanh" ) ) d= tanh(d); - else if( strmatch(next, "sin" ) ) d= sin(d); - else if( strmatch(next, "cos" ) ) d= cos(d); - else if( strmatch(next, "tan" ) ) d= tan(d); - else if( strmatch(next, "atan" ) ) d= atan(d); - else if( strmatch(next, "asin" ) ) d= asin(d); - else if( strmatch(next, "acos" ) ) d= acos(d); - else if( strmatch(next, "exp" ) ) d= exp(d); - else if( strmatch(next, "log" ) ) d= log(d); - else if( strmatch(next, "squish") ) d= 1/(1+exp(4*d)); - else if( strmatch(next, "gauss" ) ) d= exp(-d*d/2)/sqrt(2*M_PI); - else if( strmatch(next, "abs" ) ) d= fabs(d); - else if( strmatch(next, "mod" ) ) d-= floor(d/d2)*d2; - else if( strmatch(next, "max" ) ) d= d > d2 ? d : d2; - else if( strmatch(next, "min" ) ) d= d < d2 ? d : d2; - else if( strmatch(next, "gt" ) ) d= d > d2 ? 1.0 : 0.0; - else if( strmatch(next, "gte" ) ) d= d >= d2 ? 1.0 : 0.0; - else if( strmatch(next, "lt" ) ) d= d > d2 ? 0.0 : 1.0; - else if( strmatch(next, "lte" ) ) d= d >= d2 ? 0.0 : 1.0; - else if( strmatch(next, "eq" ) ) d= d == d2 ? 1.0 : 0.0; - else if( strmatch(next, "(" ) ) d= d; -// else if( strmatch(next, "l1" ) ) d= 1 + d2*(d - 1); -// else if( strmatch(next, "sq01" ) ) d= (d >= 0.0 && d <=1.0) ? 1.0 : 0.0; - else{ + d->type = e_func0; + if( strmatch(next, "sinh" ) ) d->a.func0 = sinh; + else if( strmatch(next, "cosh" ) ) d->a.func0 = cosh; + else if( strmatch(next, "tanh" ) ) d->a.func0 = tanh; + else if( strmatch(next, "sin" ) ) d->a.func0 = sin; + else if( strmatch(next, "cos" ) ) d->a.func0 = cos; + else if( strmatch(next, "tan" ) ) d->a.func0 = tan; + else if( strmatch(next, "atan" ) ) d->a.func0 = atan; + else if( strmatch(next, "asin" ) ) d->a.func0 = asin; + else if( strmatch(next, "acos" ) ) d->a.func0 = acos; + else if( strmatch(next, "exp" ) ) d->a.func0 = exp; + else if( strmatch(next, "log" ) ) d->a.func0 = log; + else if( strmatch(next, "abs" ) ) d->a.func0 = fabs; + else if( strmatch(next, "squish") ) d->type = e_squish; + else if( strmatch(next, "gauss" ) ) d->type = e_gauss; + else if( strmatch(next, "mod" ) ) d->type = e_mod; + else if( strmatch(next, "max" ) ) d->type = e_max; + else if( strmatch(next, "min" ) ) d->type = e_min; + else if( strmatch(next, "eq" ) ) d->type = e_eq; + else if( strmatch(next, "gt" ) ) d->type = e_gt; + else if( strmatch(next, "gte" ) ) d->type = e_gte; + else if( strmatch(next, "lt" ) ) { AVEvalExpr * tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gte; } + else if( strmatch(next, "lte" ) ) { AVEvalExpr * tmp = d->param[1]; d->param[1] = d->param[0]; d->param[0] = tmp; d->type = e_gt; } + else { for(i=0; p->func1_name && p->func1_name[i]; i++){ if(strmatch(next, p->func1_name[i])){ - return p->func1[i](p->opaque, d); + d->a.func1 = p->func1[i]; + d->type = e_func1; + return d; } } for(i=0; p->func2_name && p->func2_name[i]; i++){ if(strmatch(next, p->func2_name[i])){ - return p->func2[i](p->opaque, d, d2); + d->a.func2 = p->func2[i]; + d->type = e_func2; + return d; } } *p->error = "unknown function"; - return NAN; + ff_eval_free(d); + return NULL; } return d; } -static double evalPow(Parser *p, int *sign){ +static AVEvalExpr * parse_pow(Parser *p, int *sign){ *sign= (*p->s == '+') - (*p->s == '-'); p->s += *sign&1; - return evalPrimary(p); + return parse_primary(p); } -static double evalFactor(Parser *p){ +static AVEvalExpr * parse_factor(Parser *p){ int sign, sign2; - double ret, e; - ret= evalPow(p, &sign); + AVEvalExpr * e = parse_pow(p, &sign); while(p->s[0]=='^'){ + AVEvalExpr * tmp = av_mallocz(sizeof(AVEvalExpr)); + p->s++; - e= evalPow(p, &sign2); - ret= pow(ret, (sign2|1) * e); + + tmp->type = e_pow; + tmp->value = 1.; + tmp->param[0] = e; + tmp->param[1] = parse_pow(p, &sign2); + if (tmp->param[1]) tmp->param[1]->value *= (sign2|1); + e = tmp; } - return (sign|1) * ret; + if (e) e->value *= (sign|1); + return e; } -static double evalTerm(Parser *p){ - double ret= evalFactor(p); +static AVEvalExpr * parse_term(Parser *p){ + AVEvalExpr * e = parse_factor(p); while(p->s[0]=='*' || p->s[0]=='/'){ - if(*p->s++ == '*') ret*= evalFactor(p); - else ret/= evalFactor(p); + AVEvalExpr * tmp = av_mallocz(sizeof(AVEvalExpr)); + if(*p->s++ == '*') tmp->type = e_mul; + else tmp->type = e_div; + tmp->value = 1.; + tmp->param[0] = e; + tmp->param[1] = parse_factor(p); + e = tmp; } - return ret; + return e; } -static double evalExpression(Parser *p){ - double ret= 0; +static AVEvalExpr * parse_expr(Parser *p) { + AVEvalExpr * e; if(p->stack_index <= 0) //protect against stack overflows - return NAN; + return NULL; p->stack_index--; - do{ - ret += evalTerm(p); - }while(*p->s == '+' || *p->s == '-'); + e = parse_term(p); + + while(*p->s == '+' || *p->s == '-') { + AVEvalExpr * tmp = av_mallocz(sizeof(AVEvalExpr)); + tmp->type = e_add; + tmp->value = 1.; + tmp->param[0] = e; + tmp->param[1] = parse_term(p); + e = tmp; + }; p->stack_index++; - return ret; + return e; } -double ff_eval2(char *s, double *const_value, const char **const_name, +static int verify_expr(AVEvalExpr * e) { + if (!e) return 0; + switch (e->type) { + case e_value: + case e_const: return 1; + case e_func0: + case e_func1: + case e_squish: + case e_gauss: return verify_expr(e->param[0]); + default: return verify_expr(e->param[0]) && verify_expr(e->param[1]); + } +} + +AVEvalExpr * ff_parse(char *s, const char **const_name, double (**func1)(void *, double), const char **func1_name, double (**func2)(void *, double, double), char **func2_name, - void *opaque, char **error){ + char **error){ Parser p; + AVEvalExpr * e; p.stack_index=100; p.s= s; - p.const_value= const_value; p.const_name = const_name; p.func1 = func1; p.func1_name = func1_name; p.func2 = func2; p.func2_name = func2_name; - p.opaque = opaque; p.error= error; - return evalExpression(&p); + e = parse_expr(&p); + if (!verify_expr(e)) { + ff_eval_free(e); + return NULL; + } + return e; +} + +double ff_parse_eval(AVEvalExpr * e, double *const_value, void *opaque) { + Parser p; + + p.const_value= const_value; + p.opaque = opaque; + return eval_expr(&p, e); +} + +double ff_eval2(char *s, double *const_value, const char **const_name, + double (**func1)(void *, double), const char **func1_name, + double (**func2)(void *, double, double), char **func2_name, + void *opaque, char **error){ + AVEvalExpr * e = ff_parse(s, const_name, func1, func1_name, func2, func2_name, error); + double d; + if (!e) return NAN; + d = ff_parse_eval(e, const_value, opaque); + ff_eval_free(e); + return d; } #if LIBAVCODEC_VERSION_INT < ((52<<16)+(0<<8)+0) diff --git a/libavcodec/eval.h b/libavcodec/eval.h index e1510c9cf7..05a2f1ef2a 100644 --- a/libavcodec/eval.h +++ b/libavcodec/eval.h @@ -39,4 +39,12 @@ double ff_eval2(char *s, double *const_value, const char **const_name, double (**func2)(void *, double, double), char **func2_name, void *opaque, char **error); +typedef struct ff_expr_s AVEvalExpr; +AVEvalExpr * ff_parse(char *s, const char **const_name, + double (**func1)(void *, double), const char **func1_name, + double (**func2)(void *, double, double), char **func2_name, + char **error); +double ff_parse_eval(AVEvalExpr * e, double *const_value, void *opaque); +void ff_eval_free(AVEvalExpr * e); + #endif /* AVCODEC_EVAL_H */