string DocCompiler::generateCacheCode(Tree sig, const string& exp)
{
// cerr << "!! entering generateCacheCode with sig=\"" << ppsig(sig) << "\"" << endl;
string vname, ctype, code, vectorname;
int sharing = getSharingCount(sig);
Occurences* o = fOccMarkup.retrieve(sig);
// check reentrance
if(getCompiledExpression(sig, code))
{
// cerr << "!! generateCacheCode called a true getCompiledExpression" << endl;
return code;
}
// check for expression occuring in delays
if(o->getMaxDelay() > 0)
{
if(getVectorNameProperty(sig, vectorname))
{
return exp;
}
getTypedNames(getCertifiedSigType(sig), "r", ctype, vname);
gDocNoticeFlagMap["recursigs"] = true;
// cerr << "- r : generateCacheCode : vame=\"" << vname << "\", for sig=\"" << ppsig(sig) << "\"" << endl;
if(sharing > 1)
{
// cerr << " generateCacheCode calls generateDelayVec(generateVariableStore) on vame=\"" << vname << "\"" << endl;
return generateDelayVec(sig, generateVariableStore(sig, exp), ctype, vname, o->getMaxDelay());
}
else
{
// cerr << " generateCacheCode calls generateDelayVec(exp) on vame=\"" << vname << "\"" << endl;
return generateDelayVec(sig, exp, ctype, vname, o->getMaxDelay());
}
}
else if(sharing == 1 || getVectorNameProperty(sig, vectorname) || isVerySimpleFormula(sig))
{
// cerr << "! generateCacheCode : sharing == 1 : return \"" << exp << "\"" << endl;
return exp;
}
else if(sharing > 1)
{
// cerr << "! generateCacheCode : sharing > 1 : return \"" << exp << "\"" << endl;
return generateVariableStore(sig, exp);
}
else
{
cerr << "Error in sharing count (" << sharing << ") for " << *sig << endl;
exit(1);
}
return "Error in generateCacheCode";
}
//------------------------------------------------------------------------------
// Create a specific property key for the sharing count of subtrees of t
//------------------------------------------------------------------------------
void ScalarCompiler::sharingAnnotation(int vctxt, Tree sig)
{
Tree c, x, y, z;
//cerr << "START sharing annotation of " << *sig << endl;
int count = getSharingCount(sig);
if (count > 0) {
// it is not our first visit
setSharingCount(sig, count+1);
} else {
// it is our first visit,
int v = getCertifiedSigType(sig)->variability();
// check "time sharing" cases
if (v < vctxt) {
setSharingCount(sig, 2); // time sharing occurence : slower expression in faster context
} else {
setSharingCount(sig, 1); // regular occurence
}
if (isSigSelect3(sig,c,y,x,z)) {
// make a special case for select3 implemented with real if
// because the c expression will be used twice in the C++
// translation
sharingAnnotation(v, c);
sharingAnnotation(v, c);
sharingAnnotation(v, x);
sharingAnnotation(v, y);
sharingAnnotation(v, z);
} else {
// Annotate the sub signals
vector<Tree> subsig;
int n = getSubSignals(sig, subsig);
if (n>0 && ! isSigGen(sig)) {
for (int i=0; i<n; i++) sharingAnnotation(v, subsig[i]);
}
}
}
//cerr << "END sharing annotation of " << *sig << endl;
}
/**
* Test if a signal need to be compiled in a separate loop.
* @param sig the signal expression to test.
* @return true if a separate loop is needed
*/
bool VectorCompiler::needSeparateLoop(Tree sig)
{
Occurences* o = fOccMarkup.retrieve(sig);
Type t = getCertifiedSigType(sig);
int c = getSharingCount(sig);
bool b;
int i;
Tree x,y;
if (o->getMaxDelay()>0) {
//cerr << "DLY "; // delayed expressions require a separate loop
b = true;
} else if (verySimple(sig) || t->variability()<kSamp) {
b = false; // non sample computation never require a loop
} else if (isSigFixDelay(sig, x, y)) {
b = false; //
} else if (isProj(sig, &i ,x)) {
//cerr << "REC "; // recursive expressions require a separate loop
b = true;
} else if (c > 1) {
//cerr << "SHA(" << c << ") "; // expressions used several times required a separate loop
b = true;
} else {
// sample expressions that are not recursive, not delayed
// and not shared, doesn't require a separate loop.
b = false;
}
/* if (b) {
cerr << "Separate Loop for " << ppsig(sig) << endl;
} else {
cerr << "Same Loop for " << ppsig(sig) << endl;
}*/
return b;
}
/**
* Generate cache code for a signal if needed
* @param sig the signal expression.
* @param exp the corresponding C code.
* @return the cached C code
*/
string VectorCompiler::generateCacheCode(Tree sig, const string& exp)
{
string vname, ctype;
int sharing = getSharingCount(sig);
Type t = getCertifiedSigType(sig);
Occurences* o = fOccMarkup.retrieve(sig);
int d = o->getMaxDelay();
if (t->variability() < kSamp) {
if (d==0) {
// non-sample, not delayed : same as scalar cache
return ScalarCompiler::generateCacheCode(sig,exp);
} else {
// it is a non-sample expressions but used delayed
// we need a delay line
getTypedNames(getCertifiedSigType(sig), "Vec", ctype, vname);
if ((sharing > 1) && !verySimple(sig)) {
// first cache this expression because it
// it is shared and complex
string cachedexp = generateVariableStore(sig, exp);
generateDelayLine(ctype, vname, d, cachedexp);
setVectorNameProperty(sig, vname);
return cachedexp;
} else {
// no need to cache this expression because
// it is either not shared or very simple
generateDelayLine(ctype, vname, d, exp);
setVectorNameProperty(sig, vname);
return exp;
}
}
} else {
// sample-rate signal
if (d > 0) {
// used delayed : we need a delay line
getTypedNames(getCertifiedSigType(sig), "Yec", ctype, vname);
generateDelayLine(ctype, vname, d, exp);
setVectorNameProperty(sig, vname);
if (verySimple(sig)) {
return exp;
} else {
if (d < gMaxCopyDelay) {
return subst("$0[i]", vname);
} else {
// we use a ring buffer
string mask = T(pow2limit(d + gVecSize)-1);
return subst("$0[($0_idx+i) & $1]", vname, mask);
}
}
} else {
// not delayed
if ( sharing > 1 && ! verySimple(sig) ) {
// shared and not simple : we need a vector
// cerr << "ZEC : " << ppsig(sig) << endl;
getTypedNames(getCertifiedSigType(sig), "Zec", ctype, vname);
generateDelayLine(ctype, vname, d, exp);
setVectorNameProperty(sig, vname);
return subst("$0[i]", vname);
} else {
// not shared or simple : no cache needed
return exp;
}
}
}
}