[llvm] r348701 - [llvm-readobj] Little clean up inside `parseDynamicTable`

[Xing GUO via llvm-commits]

Author: higuoxing
Date: Fri Dec  7 21:32:28 2018
New Revision: 348701

URL: http://llvm.org/viewvc/llvm-project?rev=348701&view=rev
Log:
[llvm-readobj] Little clean up inside `parseDynamicTable`

Summary:
This anoymous function actually has same logic with `Obj->toMappedAddr`.

Besides, I have a question on resolving illegal value. `gnu-readelf`, `gnu-objdump` and `llvm-objdump` could parse the test file 'test/tools/llvm-objdump/Inputs/private-headers-x86_64.elf', but `llvm-readobj` will fail when parse `DT_RELR` segment. Because, the value is 0x87654321 which is illegal. So, shall we do this clean up rather then remove the checking statements inside anoymous function?

```
if (Delta >= Phdr.p_filesz)
    return createError("Virtual address is not in any segment");
```

Reviewers: rupprecht, jhenderson

Reviewed By: jhenderson

Subscribers: llvm-commits

Differential Revision: https://reviews.llvm.org/D55329

Modified:
    llvm/trunk/tools/llvm-readobj/ELFDumper.cpp

Modified: llvm/trunk/tools/llvm-readobj/ELFDumper.cpp
URL: http://llvm.org/viewvc/llvm-project/llvm/trunk/tools/llvm-readobj/ELFDumper.cpp?rev=348701&r1=348700&r2=348701&view=diff
==============================================================================
--- llvm/trunk/tools/llvm-readobj/ELFDumper.cpp (original)
+++ llvm/trunk/tools/llvm-readobj/ELFDumper.cpp Fri Dec  7 21:32:28 2018
@@ -1484,19 +1484,10 @@ template <typename ELFT>
 void ELFDumper<ELFT>::parseDynamicTable(
     ArrayRef<const Elf_Phdr *> LoadSegments) {
   auto toMappedAddr = [&](uint64_t VAddr) -> const uint8_t * {
-    const Elf_Phdr *const *I =
-        std::upper_bound(LoadSegments.begin(), LoadSegments.end(), VAddr,
-                         [](uint64_t VAddr, const Elf_Phdr_Impl<ELFT> *Phdr) {
-                           return VAddr < Phdr->p_vaddr;
-                         });
-    if (I == LoadSegments.begin())
-      report_fatal_error("Virtual address is not in any segment");
-    --I;
-    const Elf_Phdr &Phdr = **I;
-    uint64_t Delta = VAddr - Phdr.p_vaddr;
-    if (Delta >= Phdr.p_filesz)
-      report_fatal_error("Virtual address is not in any segment");
-    return Obj->base() + Phdr.p_offset + Delta;
+    auto MappedAddrOrError = Obj->toMappedAddr(VAddr);
+    if (!MappedAddrOrError)
+      report_fatal_error(MappedAddrOrError.takeError());
+    return MappedAddrOrError.get();
   };
 
   uint64_t SONameOffset = 0;