[PATCH] [ELF]: Initial implementation for ARM static linking

[Shankar Kalpathi Easwaran]

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Comment at: lib/ReaderWriter/ELF/ARM/ARMExecutableWriter.h:33-34
@@ +32,4 @@
+  void addDefaultAtoms() override {
+    _armRuntimeFile->addAbsoluteAtom("__exidx_start");
+    _armRuntimeFile->addAbsoluteAtom("__exidx_end");
+
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I couldnt find any place where this gets fixed up.

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Comment at: lib/ReaderWriter/ELF/ARM/ARMLinkingContext.h:32-33
@@ +31,4 @@
+  uint64_t getBaseAddress() const override {
+    if (_baseAddress == 0)
+      return 0x400000;
+    return _baseAddress;
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Is the base address correct for ARM ?

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Comment at: lib/ReaderWriter/ELF/ARM/ARMRelocationHandler.cpp:420-421
@@ +419,4 @@
+    } else {
+      // The atom is not in any of the loadable segments
+      assert(false);
+    }
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llvm::report_fatal_error (or) provide a reason with the assert.

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Comment at: lib/ReaderWriter/ELF/ARM/ARMRelocationPass.cpp:145-147
@@ +144,5 @@
+          llvm::dbgs() << " Name of Atom: " << atom->name().str() << "\n";
+        } llvm::dbgs()
+            << "Shared Library Atoms"
+            << "\n";
+        for (const auto &atom
----------------
indentation is not right.

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Comment at: lib/ReaderWriter/ELF/ARM/ARMRelocationPass.cpp:223
@@ +222,3 @@
+  /// @{
+  PLT0Atom *_PLT0;
+  GOTAtom *_got0;
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I dont see any initialization to _PLT0. If you are not supporting dynamic linking with this patch, Please remove dynamic linking code from this patch as its difficult to follow.

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Comment at: lib/ReaderWriter/ELF/ARM/ARMRelocationPass.cpp:241
@@ +240,3 @@
+
+  std::error_code handlePlain(const Reference &) { return std::error_code(); }
+
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Why is this empty ?

http://reviews.llvm.org/D6446