[PATCH] D30163: [ELF] - Postpone evaluation of LMA offset.

[George Rimar via Phabricator via llvm-commits]

grimar added inline comments.


================
Comment at: lld/trunk/ELF/LinkerScript.cpp:568
   if (Cmd->LMAExpr)
-    LMAOffset = Cmd->LMAExpr(Dot) - Dot;
+    CurLMA = {Cmd->LMAExpr, Dot};
   OutputSectionBase *Sec = findSection<ELFT>(Cmd->Name, *OutputSections);
----------------
ruiu wrote:
> If you change this to
> 
>   LMAOffset = [=] { return Cmd->LMAExpr(Dot) - Dot; }
> 
> I generally don't like to overuse std::pair because its member names (first and second) sometimes hurts code readability.
That would work if I do something like:

```
  if (Cmd->LMAExpr) {
    uintX_t D = Dot;
    LMAOffset = [=] { return Cmd->LMAExpr(D) - D; };
  }
```

Because you can't capture member Dot by value.
Does it look fine for you ?


================
Comment at: lld/trunk/ELF/LinkerScript.h:301
   uintX_t Dot;
-  uintX_t LMAOffset = 0;
+  std::pair<Expr, uintX_t> CurLMA;
   OutputSectionBase *CurOutSec = nullptr;
----------------
ruiu wrote:
> This can be just `Expr LMAOffset`, right?
> 
I would use std::function<uint64_t()> then. Expr assumes Dot argument which is unused.
And would complicate the initialization to:

```
LMAOffset = {[=](uint64_t) { return Cmd->LMAExpr(D) - D; }};
```


Repository:
  rL LLVM

https://reviews.llvm.org/D30163