[cfe-commits] r49987 - in /cfe/trunk: include/clang/Basic/DiagnosticKinds.def lib/CodeGen/CodeGenModule.cpp lib/CodeGen/CodeGenModule.h

[Chris Lattner]

On Apr 19, 2008, at 11:29 PM, Nate Begeman wrote:
> URL: http://llvm.org/viewvc/llvm-project?rev=49987&view=rev
> Log:
> Only generate code for static functions and global variables that  
> are actually used.
> Warn about unused static functions and variables.
> This fixes PR1998.

Nice, some minor things:

> +void CodeGenModule::EmitStatics() {
> +  // Emit code for each used static decl encountered.  Since a  
> previously unused
> +  // static decl may become used during the generation of code for  
> a static
> +  // function, iterate until no changes are made.
> +  bool Changed;
> +  do {
> +    Changed = false;
> +    for (unsigned i = 0, e = StaticDecls.size(); i != e; ++i) {
> +      // Check the map of used decls for our static. If not found,  
> continue.
> +      const Decl *D = StaticDecls[i];
> +      if (GlobalDeclMap[D] == 0)
> +        continue;

This should use:  if (!GlobalDeclMap.count(D)) continue.  Using '[D]'  
will cause an entry (with null as the value) to be inserted into the  
map.

> +      // If this is a function decl, generate code for the static  
> function if it
> +      // has a body.  Otherwise, we must have a var decl for a  
> static global
> +      // variable.
> +      if (const FunctionDecl *FD = dyn_cast<FunctionDecl>(D)) {
> +        if (FD->getBody())
> +          CodeGenFunction(*this).GenerateCode(FD);
> +      } else {
> +        const VarDecl *VD = cast<VarDecl>(D);
> +        EmitGlobalVarInit(VD);
> +      }

You can inline the 'cast<VarDecl>(D)' here.
>
> +  // Warn about all statics that are still unused at end of code  
> generation.
> +  for (unsigned i = 0, e = StaticDecls.size(); i != e; ++i) {
> +    const Decl *D = StaticDecls[i];
> +    std::string Msg = cast<NamedDecl>(D)->getName();

Maybe StaticDecls should be declared as a list of NamedDecls instead  
of Decls?  This would eliminate the cast.

Thanks for tackling this Nate!

-Chris