Resize pars_vals and make generated code scope-dependent

Author: runtingt

src/CombineCodegenImpl.cxx

@@ -250,8 +250,9 @@ void RooFit::Experimental::codegenImpl(RooParametricHist& arg, CodegenContext& c
     arg.getFlattenedMorphs(diffs_flat, sums_flat);
   }
 
+  std::string xName = ctx.getResult(arg.observable());
   std::stringstream bin_i;
-  bin_i << ctx.buildCall("RooFit::Detail::MathFuncs::parametricHistFindBin", arg.getNBins(), arg.getBins(), arg.getX());
+  bin_i << ctx.buildCall("RooFit::Detail::MathFuncs::parametricHistFindBin", arg.getNBins(), arg.getBins(), xName);
   std::stringstream code;
   code << ctx.buildCall("RooFit::Detail::MathFuncs::parametricHistEvaluate",
                         bin_i.str(),
@@ -265,7 +266,7 @@ void RooFit::Experimental::codegenImpl(RooParametricHist& arg, CodegenContext& c
                         arg.getWidths(),
                         arg.getSmoothRegion())
                     + ";\n";
-  ctx.addToCodeBody(code.str(), true);
+  ctx.addToCodeBody(code.str());
   ctx.addResult(&arg, code.str());
 }
 

src/RooParametricHist.cxx

@@ -165,6 +165,7 @@ Double_t RooParametricHist::evaluate() const
   double xVal = getX();
   int bin_i = RooFit::Detail::MathFuncs::parametricHistFindBin(N_bins, bins, xVal);
   if (bin_i < 0) return 0.0;  // Out of range
+  pars_vals_.resize(N_bins);
   pars_vals_[bin_i] = getParVal(bin_i); 
   if (bins.empty() || widths.empty()) return 0.0;
   const double* bins_ptr = bins.data();