Coverage Report

Created: 2017-09-19 22:28

/Users/buildslave/jenkins/sharedspace/clang-stage2-coverage-R@2/llvm/tools/lld/ELF/Arch/AVR.cpp
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//===- AVR.cpp ------------------------------------------------------------===//
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//
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//                             The LLVM Linker
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//
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// This file is distributed under the University of Illinois Open Source
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// License. See LICENSE.TXT for details.
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//
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//===----------------------------------------------------------------------===//
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//
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// AVR is a Harvard-architecture 8-bit micrcontroller designed for small
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// baremetal programs. All AVR-family processors have 32 8-bit registers.
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// The tiniest AVR has 32 byte RAM and 1 KiB program memory, and the largest
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// one supports up to 2^24 data address space and 2^22 code address space.
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//
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// Since it is a baremetal programming, there's usually no loader to load
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// ELF files on AVRs. You are expected to link your program against address
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// 0 and pull out a .text section from the result using objcopy, so that you
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// can write the linked code to on-chip flush memory. You can do that with
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// the following commands:
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//
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//   ld.lld -Ttext=0 -o foo foo.o
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//   objcopy -O binary --only-section=.text foo output.bin
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//
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// Note that the current AVR support is very preliminary so you can't
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// link any useful program yet, though.
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//
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//===----------------------------------------------------------------------===//
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#include "Error.h"
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#include "InputFiles.h"
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#include "Symbols.h"
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#include "Target.h"
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#include "llvm/Object/ELF.h"
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#include "llvm/Support/Endian.h"
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using namespace llvm;
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using namespace llvm::object;
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using namespace llvm::support::endian;
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using namespace llvm::ELF;
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using namespace lld;
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using namespace lld::elf;
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namespace {
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class AVR final : public TargetInfo {
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public:
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  RelExpr getRelExpr(uint32_t Type, const SymbolBody &S, const InputFile &File,
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                     const uint8_t *Loc) const override;
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  void relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const override;
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};
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} // namespace
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RelExpr AVR::getRelExpr(uint32_t Type, const SymbolBody &S,
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0
                        const InputFile &File, const uint8_t *Loc) const {
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0
  switch (Type) {
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0
  case R_AVR_CALL:
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    return R_ABS;
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  default:
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    error(toString(&File) + ": unknown relocation type: " + toString(Type));
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    return R_HINT;
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  }
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0
}
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void AVR::relocateOne(uint8_t *Loc, uint32_t Type, uint64_t Val) const {
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  switch (Type) {
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  case R_AVR_CALL: {
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    uint16_t Hi = Val >> 17;
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    uint16_t Lo = Val >> 1;
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    write16le(Loc, read16le(Loc) | ((Hi >> 1) << 4) | (Hi & 1));
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    write16le(Loc + 2, Lo);
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    break;
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  }
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  default:
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    error(getErrorLocation(Loc) + "unrecognized reloc " + toString(Type));
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  }
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}
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TargetInfo *elf::getAVRTargetInfo() {
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  static AVR Target;
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  return &Target;
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0
}