void HqlCppCaseInfo::buildChop2Map(BuildCtx & ctx, const CHqlBoundTarget & target, CHqlBoundExpr & test, unsigned start, unsigned end)
{
BuildCtx subctx(ctx);
if ((end - start) <= 3) // (1,2,3) avg(2) cf. (2,2,3) avg(2.3)
{
//optimize the case where they all create the same value
bool same = true;
unsigned index;
for (index=start+1; index < end; ++index)
{
if (queryReturn(index-1) != queryReturn(index))
{
same = false;
break;
}
}
if (same)
{
CompoundBuilder cb(no_or);
for (index=start; index < end; ++index)
{
IHqlExpression * compare = queryCompare(index);
IHqlExpression * cond = createCompareExpr(no_eq, test.getTranslatedExpr(), LINK(compare));
cb.addOperand(cond);
}
OwnedHqlExpr compound = cb.getCompound();
translator.buildFilter(subctx, compound);
translator.buildExprAssign(subctx, target, queryReturn(start));
}
else
{
IHqlStmt * stmt = NULL;
for (index=start; index < end; ++index)
{
if (stmt)
subctx.selectElse(stmt);
IHqlExpression * compare = queryCompare(index);
OwnedHqlExpr cond = createCompareExpr(no_eq, test.getTranslatedExpr(), LINK(compare));
CHqlBoundExpr bound;
translator.buildExpr(subctx, cond, bound);
stmt = subctx.addFilter(bound.expr);
translator.buildExprAssign(subctx, target, queryReturn(index));
}
}
}
else
{
unsigned mid = start + (end - start) / 2;
IHqlExpression * compare = queryCompare(mid);
OwnedHqlExpr cond = createCompareExpr(no_lt, test.getTranslatedExpr(), LINK(compare));
CHqlBoundExpr bound;
translator.buildExpr(subctx, cond, bound);
IHqlStmt * stmt = subctx.addFilter(bound.expr);
buildChop2Map(subctx, target, test, start, mid);
subctx.selectElse(stmt);
buildChop2Map(subctx, target, test, mid, end);
}
}
bool HqlCppCaseInfo::buildAssign(BuildCtx & ctx, const CHqlBoundTarget & target)
{
if (pairs.ordinality() == 0)
{
translator.buildExprAssign(ctx, target, defaultValue);
}
else if (cond.get() && constantCases)
{
processBranches();
BuildCtx subctx(ctx);
CHqlBoundExpr test;
buildSwitchCondition(ctx, test);
if (complexCompare)
{
if (pairs.ordinality() > INLINE_COMPARE_THRESHOLD)
{
if (okToAlwaysEvaluateDefault() || hasLibraryChop())
buildLoopChopMap(subctx, target, test);
else
buildGeneralAssign(subctx, target);
}
else
{
if (okToAlwaysEvaluateDefault())
buildChop3Map(subctx, target, test);
else
buildGeneralAssign(subctx, target);
}
}
else
{
ITypeInfo * condType = test.queryType()->queryPromotedType();
if (!queryBuildArrayLookup(subctx, target, test))
{
if (condType->getTypeCode() != type_real)
{
OwnedHqlExpr search = test.getTranslatedExpr();
if (constantValues && (condType->getTypeCode() == type_int) && (pairs.ordinality() > INTEGER_SEARCH_THRESHOLD) && canBuildStaticList(resultType))
buildIntegerSearchMap(subctx, target, search);
else
buildSwitchMap(subctx, &target, test.expr);
}
else
{
if (okToAlwaysEvaluateDefault() && pairs.ordinality() > 4)
{
translator.buildExprAssign(ctx, target, defaultValue);
buildChop2Map(subctx, target, test, 0, pairs.ordinality());
}
else
buildGeneralAssign(subctx, target);
}
}
}
}
else
buildGeneralAssign(ctx, target);
return true;
}